Que Pasa!

Are political leanings all in the genes?

transkryptome — Mon, 17 Mar 2008 20:49:33 GMT

From New Scientist Print Edition. THE race to become the most powerful politician on earth is well under way, and the US is gripped by election fever. In newsrooms and bars across the land, liberals and conservatives are slugging it out, trying to convince each other that their way of thinking is right. They may be wasting their breath. According to an emerging idea, political positions are substantially determined by biology and can be stubbornly resistant to reason. "These views are deep-seated and built into our brains. Trying to persuade someone not to be liberal is like trying to persuade someone not to have brown eyes. We have to rethink persuasion," says John Alford, a political scientist at Rice University in Houston, Texas. Evidence to support this idea is growing. For example, twin studies suggest that opinions on a long list of issues, from religion in schools to nuclear power and gay rights, have a substantial genetic component. The decision to vote rather than stay at home on election day may also be linked to genes. Neuroscientists have also got in on the act, showing that liberals and conservatives have different patterns of brain activity. The idea that our politics are in part shaped by our genes is not itself new, but it has only recently come to the attention of political scientists. In 2005, Alford published a paper in which he analysed two decades of work in behavioural genetics, including a huge database containing the political opinions of 30,000 twins from Virginia (American Political Science Review, vol 99, p 153). He found that identical twins were more likely than non-identical twins to give the same answers to political questions. For example, on the issue of whether property should be taxed, four-fifths of identical twins gave the same answer, compared to two-thirds of non-identical twins. What could account for this? Well, given that identicals have the same genes while non-identicals share only half their genes, the fact that identical twins gave the same answer more often than non-identicals suggests the answer must be influenced by their genes. These results are startling. Evolution is a slow process that takes centuries to effect changes, so why would it endow us with genes that affect issues which seem fleeting on an evolutionary scale? Frank Sulloway, a psychologist at the University of California, Berkeley, backs the idea that inheritance can influence political attitudes, but admits the results may sound odd. "There's no such thing as a gene for disliking hippies," he says. The point is that certain genes shape personality traits, and these are linked to political opinion. “There is no such thing as a gene for disliking hippies” In 2003, John Jost, a psychologist at New York University, and colleagues surveyed 88 studies, involving more than 20,000 people in 12 countries, that looked for a correlation between personality traits and political orientation (American Psychologist, vol 61, p 651). Some traits are obviously going to be linked to politics, such as xenophobia being connected with the far right. However, Jost uncovered many more intriguing connections. People who scored highly on a scale measuring fear of death, for example, were almost four times more likely to hold conservative views. Dogmatic types were also more conservative, while those who expressed interest in new experiences tended to be liberals. Jost's review also noted research showing that conservatives prefer simple and unambiguous paintings, poems and songs. Jost noticed a pattern emerging from these results that fits neatly into existing models of personality. Many psychologists believe personality can be categorised into five classes, relating to conscientiousness, openness, extroversion, agreeableness and neuroticism. The latter two seem to have little to do with political orientation. Scores on the conscientiousness scale, however, show a significant correlation with position within the political spectrum (see Diagram). A much stronger link exists between political orientation and openness, which psychologists define as including traits such as an ability to accept new ideas, a tolerance for ambiguity and an interest in different cultures. When these traits are combined, people with high openness scores turn out to be almost twice as likely to be liberals. Combine the genetic influences on personality with the political tendencies of different personality types, and the idea that genetics shapes political tendencies seems very plausible indeed. All of the big five personality traits are highly heritable (Journal of Research in Personality, vol 32, p 431), with several studies suggesting that around half of the variation in openness scores is a result of genetic differences. Some traits that are linked to openness, such as being sociable, are also known to be influenced by the levels of neurotransmitters in the brain. And levels of these chemicals are controlled in part by genes. So while there isn't a gene for liking hippies, there is probably a set of genes that influences openness, which in turn may influence political orientation. To join the dots in the argument, researchers next need to identify the brain areas and genes that shape political thinking. No one has yet identified a gene that correlates with liberalism or conservatism, for instance, but James Fowler, a political scientist at the University of California, San Diego, thinks the decision to vote rather than stay at home on election day may be linked to individual genes. The act of voting inevitably has an emotional dimension. Voters generally have a certain degree of trust in their chosen candidate, for example. That suggests that two well-studied genes may be involved: 5HTT and MAOA, which both help control the levels of serotonin, a neurotransmitter that also influences brain areas linked with trust and social interaction. People with versions of the genes that are better at regulating serotonin tend to be more sociable. According to Fowler's hypothesis, they should also be more likely to vote. In a study currently under review at The Journal of Politics, Fowler confirms that his hunch was correct. Using data on 2500 adults from across the US, he shows that people whose version of the MAOA gene is efficient at regulating the brain chemical are 1.3 times more likely to vote than those with a version that is less efficient. By itself, 5HTT did not show such an effect. But Fowler found that this gene interacted with the environment in an intriguing way. Members of religious groups are known to be more likely to vote and, among this subset of subjects, those with a particular version of 5HTT were 60 per cent more likely to vote. Many other genes are likely to be involved. In a paper presented in April 2007 to the annual conference of the Midwest Political Science Association, held in Chicago, Ira Carmen, of the University of Illinois at Urbana-Champaign, discussed D4DR, a gene involved in regulating levels of the neurotransmitter dopamine. Itis known that high levels of dopamine can cause obsessive-compulsive disorder. Carmen speculates that dopamine might therefore be linked to the need to impose order on the world. If so, variants of the D4DR gene that lead to higher levels of dopamine should be found more frequently in conservatives. Carmen plans to apply for a grant to study this and other issues in around 200 or so individuals. These gene studies are not the only way in which researchers are trying to pin politics down to more fundamental science. If Jost's personality work is correct, the differences between conservatives and liberals should show up in measures of brain activity. Tasks that involve dealing with conflicting information, for example, are known to activate an area of the brain known as the anterior cingulate cortex (ACC). Since liberals are generally more open to conflicting ideas, activity in this area of the brain would be expected to differ between them and conservatives. Last September, David Amodio, a neuroscientist at New York University, showed that it does. He asked around 40 people to complete a simple test, in which they had to press a button as soon as a certain letter flashed up on a computer screen (Nature Neuroscience, vol 10, p 1246). The letter appeared in most rounds of the test and subjects soon learned to respond fast. In one out of five cases, however, a different letter appeared. Participants were not supposed to press the button but, having grown used to seeing the "right" letter, many did so accidentally. The ability to hold back and resist the habit of pressing the button is used as an analogy for dealing with conflicting sources of information, and to measure individuals' capacity to manage them. As he predicted, Amodio found a correlation between the strength of liberal attitudes and scores on the test. More importantly, he was able to link that difference to brain activity. Electrodes placed on subjects' skulls revealed that liberals had greater ACC activity when they had to hold back from pressing the button. Liberals also had higher activity immediately after making a mistake, and the greater the activity, the better their performance over many rounds. The results, says Amodio, suggest that basic brain mechanisms, such as those that control habit formation, may distinguish liberal minds from conservative ones. But some studies linking biology to political attitudes need to be taken with a pinch of salt. One recent brain-scan study, published in The New York Times as an opinion piece, was pilloried in the press for being marketing, not science. The study was criticised in part because the researchers involved had links to FKF Applied Research, a firm which employs brain scanning in its market research work. And there is no shortage of critics who question the whole idea of linking politics with biology. Personality studies in particular have been singled out as sloppy science, in part because qualitative traits like openness cannot be measured in the way that height or eye colour can. To gauge personality, psychologists generate a series of questions designed to measure the trait of interest. Asking a subject whether they "jump into things without thinking" is one way to measure openness. But some of the questions on the tests assess issues that are political in nature, such as a subject's views about foreigners. If this is the case, "the correlation is completely circular", says Evan Charney, a political scientist at Duke University in Durham, North Carolina. Charney has a more general criticism of the personality work. As others have pointed out, a rather unflattering view of conservatives emerges from the studies. They are portrayed as dogmatic, routine-loving individuals, while liberals come across as free-spirited and open-minded folk. "I keep expecting Jost to show that conservatism is negatively correlated with penis size," jokes Charney. He feels that inherent biases in the make-up of academia, which is dominated by liberals, leads to the "pathologising of conservatism". This last criticism is difficult to dismiss. "It's hard to come up with totally unbiased language," admits Sulloway. However, the details of the language are not critical to the overall result. When political questions are weeded out, the results remain the same, he says. And Jost points out that conservative academics have run personality studies and come up with similar results to their liberal colleagues. "We are all pretty much finding the same kinds of differences," he says. Even if the personality differences between people who hold varying political views turn out to be real, others are sceptical we will ever understand the genetics that underlie them. Lindon Eaves, a behavioural geneticist at Virginia Commonwealth University in Richmond, helped assemble much of the data that Alford reviewed in 2004. He says that complex traits such as openness are likely to be determined by the combined action of a large number of genes. It is not impossible to identify them, but previous experience suggests it will be tough. Eaves points out that studies of twins have shown schizophrenia to have a substantial inherited component, but the jury is still out on whether we will find the individual genes involved. We may soon find out whether Carmen and others will prove Eaves wrong. Next March, Carmen is inviting over 50 geneticists, politics researchers and neuroscientists to a conference at the University of Illinois at Urbana-Champaign to discuss such ideas, in the hope of giving birth to a whole new field of study. Even without a detailed understanding of the genes involved, these studies could influence real-world politics. At worst, the research could be interpreted in a depressing way. Jost and others speculate that all societies contain groups analogous to western liberals and conservatives: one wants to bring in new ideas, the other resists change. In different times and areas of the world, the party names differ, as do the topics of contention. Yet politics will always be characterised by two groups pulling in different directions. If the genetic basis means these groups are hard-wired to disagree, it makes debate and policy analyses seem a little pointless. A liberal conspiracy? Those involved in day-to-day politics do not see it that way. In part, that may be because the studies have attracted little attention outside academia. Of the researchers that New Scientist spoke to, none said that professional politicians had expressed an interest in their work. Some political think tanks know about the results, but view them with suspicion. At the American Enterprise Institute, a pro-free-market group, scholar David Frum says that he is "flattered by the evidence that conservatives are more honest and dutiful than liberals". But given the huge number of variables that affect the outcome of an election, it would be a foolhardy researcher who would draw generalisations from Jost's work, he says. Those involved in the research add that even if we do find genes that have a powerful influence on politics, it will still be worth having political debates. Alford says his work shows that our reaction to homosexuality, like homosexuality itself, is in part determined by our genes. But over time, he adds, policy still changes. Arguments over gay rights in Europe and North America now focus on issues of discrimination at work and the right to marry. Just 50 years ago, much of the debate was about whether homosexuality should be legal. The two sides still do not understand each other, but protest movements, media pressure and other factors have helped change the issues they fight over. "The fact that people exist at poles doesn't eliminate the persuasive element of politics," says Alford. So the guy at the bar may never agree with you, but perhaps realising that can be liberating. "We spend a lot of energy getting upset with the other side," says Alford. We often think our opponents are misinformed or stubborn. Accepting that people are born with some of their views changes that, Alford points out. Come to terms with these differences, and you can spend the energy now wasted on persuasion on figuring out ways of accommodating both points of view.

Music special: The illusion of music

transkryptome — Mon, 17 Mar 2008 20:43:42 GMT

23 February 2008 From New Scientist Print Edition. Daniel Levitin IMAGINE that you stretch a pillowcase tightly across the opening of a bucket, and different people throw ping-pong balls at it from different distances. They can each throw as many balls as they like, and as often as they like. Your job is to figure out, just by looking at how the pillowcase moves up and down, how many people there are, who they are and whether they are walking towards you, away from you or standing still. This is essentially the problem your auditory system has to contend with when it uses the eardrum as the gateway to hearing. Sound is transmitted through the air by molecules vibrating at certain frequencies. These bombard the eardrum, causing it to wiggle in and out depending on how hard they hit it (related to the volume, or amplitude, of the sound) and how fast they are vibrating (related to what we call pitch). But there is nothing in the molecules that tells the eardrum where they came from, or which ones are associated with which object. Voices may be mixed in with other voices, or the sounds of machines, wind and footsteps. Most of the time the input is incomplete or ambiguous. So how does the brain figure out, from this disorganised mixture of molecules beating against a membrane, what is out there in the world? Most people assume that the world is just as they perceive it to be. Yet experiments have forced researchers, including myself, to confront the reality that this is not the case. What we actually hear is the end of a long chain of mental events that give rise to an impression - a mental image - of the physical world. Nowhere is this more striking than in the perceptual illusion in which our brain imposes structure and order on a sequence of sounds to create what we call music. The chain of mental events begins with a process called feature extraction. The brain extracts basic, low-level features from the music, using specialised neural networks that decompose the signal into information about pitch, timbre, spatial location, loudness, reverberant environment, tone durations and the onset times for different notes (and for different components of tones). This bottom-up processing of basic elements occurs in the peripheral and phylogenetically older parts of our brains. Next comes a process called integration. Parts of the higher brain - mostly in the frontal cortex - receive the basic features from lower brain regions and work top-down to integrate them into a perceptual whole. The brain faces three difficulties in feature extraction and integration. First, the information arriving at the sensory receptors is undifferentiated in terms of location, source and identity. Second, the information is ambiguous: different sounds can give rise to similar or identical patterns of activation on the eardrum. Third, the information is seldom complete. Parts of the sound may be masked by other sounds, or lost. The brain has to make a calculated guess about what is really out there. So, auditory perception is a process of inference. And when the sensory input is music, these inferences include several factors over and above the sounds themselves: what has come before in the piece of music we are hearing; what we remember will come next if the music is familiar; what we expect will come next if the genre or style is familiar; and any additional information we may have, such as a summary of the music that we have read, a sudden movement by a performer or a nudge by the person sitting next to us. The brain thus constructs a representation of reality, based on both the component features of what we actually hear and our expectations of what we think we should be hearing. There are good evolutionary reasons for this - a perceptual system that can restore missing information can help us make quick decisions in threatening situations - but it is not without drawbacks. The top-down expectations can cause us to misperceive things by resetting some of the circuitry in the bottom-up processors. This is partly the neural basis for perceptual illusions such as the one demonstrated by cognitive psychologist Richard Warren from the University of Wisconsin. He recorded a sentence, "The bill was passed by both houses of the legislature", cut out part of it from the recording tape and then replaced the missing piece with a burst of white noise (static) of the same duration. Nearly everyone who heard the altered recording reported that they heard both a sentence and static. Yet a large proportion of people couldn't tell when the static occurred because the auditory system had filled in the missing speech information, so that the sentence seemed to be uninterrupted. This filling-in phenomenon is not just a laboratory curiosity. Composers exploit the same principle, knowing that our perception of a melodic line will continue, even if part of it is obscured by other instruments. It also happens whenever we hear the lowest notes on the piano or double bass. We are not actually hearing 27.5 or 35 hertz, because those instruments are typically incapable of producing much energy at these ultra-low frequencies. Instead, our ears are filling in the information and giving us the illusion that the pitch is that low. Most contemporary recordings contain another type of auditory illusion. Our brains use cues about the spectrum of the sound and the types of echoes to tell us about the auditory world around us, much as a mouse uses its whiskers to learn about the physical world around it. Recording engineers have learned to mimic those cues to imbue recordings with a real-world, lifelike quality even when they are made in sterile recording studios. Artificial reverberation makes vocalists and lead guitars sound as if they are coming from the back of a concert hall, even when we are listening on headphones and the sound is an inch away from our ears. The same principles can also generate auditory tricks, such as making a guitar sound as if it is 10 feet wide and your ears are right where the soundhole should be. Special effects Recorded music allows us to experience other sensory impressions that we never actually have in the real world. Recording engineers and musicians create special effects that tickle our brains by stimulating neural circuits that evolved to discern important features of our auditory environment. For example, our brains can estimate the size of an enclosed space on the basis of the reverberation and echo present in the signal that hits our ears. Even though few of us understand the equations necessary to describe how one room differs from another, we can all tell whether we are standing in a small tiled bathroom, a medium-sized concert hall or a large church with high ceilings. And we can tell what size room the singer or speaker is in when we hear recordings of voices. Recording engineers exploit this ability to create what I call "hyper-realities", playing with our perceptions of space in the auditory equivalent of the cinematographer's trick of mounting a camera on the bumper of a speeding car. “Recorded music allows us to experience sensory impressions that we never have in the real world” Another illusion involves timing. Our brains are exquisitely sensitive to timing information. We are able to localise objects in the world based on differences of only a few milliseconds between the time of arrival of a sound at one of our ears versus the other. Many of the special effects we love to hear in recorded music are based on this sensitivity. The sounds of jazz guitarist Pat Metheny or that of David Gilmour of Pink Floyd use multiple delays of the signal to give an otherworldly, haunting effect that triggers parts of our brains in ways that humans had never experienced before, simulating the sound of an enclosed cave with multiple echoes such as would never actually occur in the real world - the auditory equivalent of the barbershop mirrors that repeat infinitely. Perhaps the ultimate illusion in music, however, is the illusion of structure and form. There is nothing in a sequence of notes themselves that creates the rich emotional associations we have with music, nothing about a scale, a chord or a chord sequence that intrinsically causes us to expect a resolution. Our ability to make sense of music depends on experience and on neural structures that learn and can modify themselves with each new song or piece of music we hear, and with each new listen to music we are already familiar with. Our brains learn a kind of musical grammar that is specific to the music of our culture, just as we learn to speak the language of our culture. This becomes the basis for our understanding of music, and ultimately the basis for what we like in music, what music moves us, and how it moves us. Top five musical illusions http://www.newscientist.com/channel/being-human/dn13355-music-special-five-great-auditory-illusions-.html In piano works such as Chopin's Fantasy-Impromptu in C-sharp Minor, opus 66, or Sinding's The Rustle of Spring, the notes go by so quickly that an illusory melody emerges. When the notes are close enough together in time, the melody "pops out" because the perceptual system binds them together, giving an emergent impression of tunefulness. Play the tune slowly and this disappears. In a Sardinian style of a cappella singing studied by Bernard Lortat-Jacob at the Musée de l'Homme in Paris, a fifth female voice called the quintina (literally "fifth one" in Sardinian) emerges from four male voices when their harmony and timbres are just right. The voice is said to be that of the Virgin Mary coming to reward the singers for their piety, but in fact it is simply a misperception of the chord and its harmonics. The Eagles' song, One of These Nights, opens with a pattern played by bass and guitar that sounds like one instrument. The bass plays a single note, and the guitar adds a glissando, but the perceptual effect is of the bass sliding due to the gestalt principle of good continuation, which binds together two objects when the trajectory of one implies the continued trajectory of another. Jazz pianist George Shearing created a new timbral effect by having a guitar (or in some cases, vibraphone) precisely match what he was playing on the piano. Listeners come away wondering, "What is that new instrument?", when in reality it is two separate instruments whose sounds have perceptually fused. In Lady Madonna, the Beatles sing into their cupped hands during an instrumental break and we could swear that there are saxophones playing. This perception is based on the unusual timbre they achieve, coupled with our expectation that saxophones should be playing in a song of this genre. (This is not to be confused with the actual saxophone solo that occurs in the song.) They just don't get it History is littered with figures noted for their hopeless unmusicality. Ulysses S. Grant, the 18th president of the United States, had a tin ear and found music profoundly irritating; Che Guevara famously couldn't distinguish one piece of music from another. Once, such people would have been described as "tone deaf"; today they are seen as much more interesting than that. In the past few years it has become clear that the inability to hold a tune can sometimes be caused by a neurological condition called congenital amusia, which completely robs people of what is normally an instinctive and spontaneous appreciation of music. No wonder the condition has become a major research topic in the bid to understand the mysteries of how the brain handles music. The first case report of "note deafness" appeared in 1878, and the literature is full of anecdotal accounts of people with a lifelong failure of music perception. It wasn't until 2002, however, that the first proper study of congenital amusia was published. A team led by Isabelle Peretz of the University of Montreal in Canada reported the case of Monica, a woman in her early 40s who had always lacked even the most basic of musical abilities (Neuron, vol 33, p 185). Peretz concluded that Monica's problem was a failure to detect pitch changes in melodies. Played two notes in sequence, she could rarely tell whether the second was higher or lower than the first or had the same pitch. Most people can easily distinguish small differences in pitch - half a semitone, say - but for amusics, even a leap of an octave, equivalent to the first two notes of Somewhere Over The Rainbow, can be barely perceptible. Tones and semitones are the building blocks of melody, so no wonder amusics find music monotonous in more than one sense of the word. Peretz and others have since documented dozens of similar cases. These people all have normal hearing, intelligence and memory, but absolutely no grasp of melody. For them, one tune sounds very much like another, familiar songs are unrecognisable without lyrics, and dissonant chords that cause most of us to wince elicit no response. Amusics cannot sing, though they often don't recognise this. The condition is unusual but not particularly rare - the accepted figure is 4 per cent of the population - and it runs in families. So what causes congenital amusia? According to Peretz, the best explanation is that the human brain is equipped with a specialised "module" for processing melody, which occasionally fails to develop properly. That would explain why amusia appears to affect musical perception alone. If correct, music, like language, is an innate human adaptation that was hard-wired into our brains by evolution. AUDITORY CHEESECAKE? Not everyone agrees with this view, however. Steven Pinker once famously described music as "auditory cheesecake" - pleasurable but with no adaptive function. What's more, there is some evidence that amusia is not a purely musical deficit but is linked to problems with language or spatial processing. So perhaps amusia (and by extension, normal music perception) is rooted in the brain circuits that handle intonation in language, or that look after the concepts of "highness" and "lowness" central to our mental representations of melody. Peretz's group and others are now scanning the brains of amusics in search of anatomical anomalies that might lead them to the underlying problem. So far they have found some minor differences in the thickness of white matter in a brain area called the right inferior frontal gyrus - a region linked with musical pitch perception and melodic memory (Brain, vol 129, p 2562). They are also searching for the genes that make amusia heritable, in the hope of gaining new insight into abnormal brain development in amusia (The American Journal of Human Genetics, vol 81, p 582). Another key question is whether congenital amusia is one condition or several. Some amusics like listening to music because they enjoy the rhythms, but Peretz's team has found that around half their subjects have a problem with rhythm perception. This suggests there may be a related condition that wipes out timing as well as melody. There's also the problem of "clatterers" - amusics to whom music sounds like a drainpipe being hit with a wrench. "Only a very few amusics hear clattering," says Peretz. "For the majority, music is just confusing." That has led some researchers to propose a separate disorder of music perception called dystimbria, which prevents people from perceiving musical "colour", or timbre. Whether amusia is one condition or many, the hope is that understanding it better will benefit those unfortunates excluded from the profound pleasure of music. Peretz thinks that with early intervention it might be possible to tap into the natural plasticity of the brain and stem some of the damage. "There's no chance of helping adults," she says. "We've tried. But with children, maybe."

Ultrasound nails location of the elusive G spot

transkryptome — Mon, 17 Mar 2008 20:25:10 GMT

20 February 2008 From New Scientist Print Edition. FOR women, it is supposed to trigger one of the most intense orgasms imaginable, with waves of pleasure spreading out across the whole body. If the "G spot orgasm" seems semi-mythical, however, that's because there has been scant evidence of its existence. Now for the first time gynaecological scans have revealed clear anatomical differences between women who claim to experience vaginal orgasms involving a G spot and those who don't. It might mean that there is a G spot, after all. What's more, a simple test could tell you if it's time to give up the hunt, or if your partner just needs to try harder. “A simple test could tell you if it is time to give up the hunt for your G spot or if your partner just needs to try harder” "For the first time it is possible to determine by a simple, rapid and inexpensive method if a woman has a G spot or not," says Emmanuele Jannini at the University of L'Aquila in Italy, who carried out the research. Jannini had already found biochemical markers relating to heightened sexual function in tissue between the vagina and urethra, where the G spot is said to be located. The markers include PDES - an enzyme that processes the nitric oxide responsible for triggering male erections (see New Scientist, 6 July 2002, p 23). However, the team had been unable to link the presence of these markers to the ability to experience a vaginal orgasm - that is, an orgasm triggered by stimulation of the front vaginal wall without any simultaneous stimulation of the clitoris. So Jannini's team took a different approach, and used vaginal ultrasound to scan the entire urethrovaginal space - the area of tissue between the vagina and urethra thought to house the G spot (see Diagram). The team scanned nine women who said they had vaginal orgasms and 11 who said they didn't. They found that tissue in the urethrovaginal space was thicker in the first group of women (Journal of Sexual Medicine, DOI: 10.1111/j.1743-6109.2007.00739.x). This means, says Jannini, that "women without any visible evidence of a G spot cannot have a vaginal orgasm". Other researchers question whether what Jannini says is the G spot is a distinct structure or the internal part of the clitoris. The urethrovaginal space is rich in blood vessels, glands, muscle fibres, nerves, and - in some women - a remnant of the embryological prostate called the Skene's glands. Some researchers have suggested that the Skene's glands are involved in triggering vaginal orgasms and, more controversially, enable a small number of women to ejaculate (see "Can women ejaculate or not?"). "The authors found a thicker vaginal wall near the urethra and hypothesise this may be related to the presence of the controversial G spot," says Tim Spector at St Thomas' Hospital in London. "However, many other explanations are possible - such as the actual size of the clitoris, which, although not measured in this study - appears highly variable." Others challenge the notion that the G spot is missing in women who don't experience orgasm. "It is an intriguing study, but it doesn't necessarily mean that women who don't experience orgasm don't have any tissue there," says Beverly Whipple at Rutger's University School of Nursing in Newark, New Jersey, whose team coined the term "G spot" in 1981. Whipple's studies suggest that all women describe some degree of sensitivity in the area where the G spot should be. She says the next step is to ask women to stimulate themselves and then repeat the ultrasounds, as the area is believed to swell in response to physical pressure. This might reveal that all women have G spots. Another possibility is that the women who experienced vaginal orgasms had learned to do so through practice, which has altered their anatomy, much like exercising a muscle makes it grow, says Leonore Tiefer, a psychiatrist at New York University School of Medicine. "The research would be much stronger if women without vaginal orgasm were taught how to have this experience and then repeated measurements were taken of the urethral-vaginal area," she says. "Of course this would involve teaching their partners a great deal." She would also have liked to see more extensive questioning of the women to fully understand their sexual practices. Jannini accepts that there are limitations to his study. In particular, the small number of women he studied doesn't allow him to say what proportion of all women have G spot - although it would seem that a large number do not. This tentative conclusion is supported by previous questionnaire-based studies such as The Hite Report, which found that 70 per cent of women do not have orgasms through intercourse, but are able to experience orgasm easily by direct clitoral stimulation. Studies of identical and non-identical twins also support the idea that there may be physiological differences between women who do and don't experience vaginal orgasms. In 2005, Spector found that up to 45 per cent of the differences between women in their ability to reach orgasm could be explained by their genes (see New Scientist, 11 June 2005, p 6). "We know that genes are partly responsible for the variation in women's responses and this study raises the possibility that local genital differences rather than purely genetic differences in brain responses or personality may be important," says Spector. Elisabeth Lloyd of Indiana University in Bloomington, and author of The Case of the Female Orgasm, agrees. "If Jannini's correlation does hold true, it would help explain the fact that most women do not reliably have orgasm with intercourse," she says. Jannini is now planning larger studies to confirm his findings, and measure how many women have a G spot - if that is indeed what he has been measuring. Eventually, he says, ultrasound could be used to test whether a woman has a G spot or not. If she does, it may even be possible to increase its size using testosterone, which both the clitoris and Skene's glands can respond to. This could increase sexual responsiveness, but could be dangerous in women with normal testosterone levels. Jannini is running a trial in post-menopausal women and those who have experienced early menopause to see if testosterone treatment can increase the size of the G spot as measured by vaginal ultrasound. Lloyd thinks Jannini's findings could make it harder to promote the idea that women who find it difficult to orgasm are suffering from some kind of sexual dysfunction, as it suggests there are physiological differences between women. "The wide variability among women in their patterns of sexual response has made the pharmaceutical industry's challenge all the greater," she says. "If this research holds up, they would need to be very clear in marketing any product they eventually come up with." Those women who suspect they may not have a G spot need not despair. "They can still have a normal orgasm through stimulation of the clitoris," Jannini says. In fact, Jannini thinks his study should reassure women who have never experienced a vaginal orgasm that this is completely normal. "One clear finding is that each woman is different. This is one reason why women are so interesting." Can women ejaculate or not? Female ejaculation is considered rare in the west, and even, by some, abnormal. In Rwanda, however, it is the norm. Social scientists Marian Koster and Lisa Price of Wageningen University in the Netherlands interviewed 11 women and two men in Rwanda about "gukuna imishino", which is the practice of elongating the labia minora, the inner vaginal lips. "The Rwandan women and men we interviewed were clear in their opinion that all Rwandan women are able to ejaculate, the ejaculation being different from the mere squirting of urine," Koster says. "Elongated labia are seen as crucial in this respect." From around puberty onwards, Rwandan girls start stretching the labia minora using plant extracts with antiseptic and anti-inflammatory properties, with the aim of achieving a length of about 5 centimetres. The WHO considers this practice as a form of genital mutilation, but Koster and Price argue that it should be reclassified as genital modification. "We believe that there are cultural practices that are not harmful to women's integrity and rights," says Koster. Their interviewees reported, and Koster and Price speculate, that labial elongation increases the sexual pleasure of both sexes. "Since the labia minora swell during sexual excitement, there is a larger surface area for penile friction during coitus," they write (Culture, Health & Sexuality, DOI: 10.1080/13691050701775076).

The Pharaoh's Pharmacists

transkryptome — Thu, 20 Dec 2007 17:50:27 GMT

15 December 2007 From New Scientist Print Edition AS EGYPTIAN mummies go, Asru is a major celebrity. During her life in the 8th century BC, she was known for her singing at the temple of Amun in Karnak; now she is famous for her medical problems. Forensic studies have revealed that although Asru lived into her sixties, she was not a well woman. She had furred-up arteries, desert lung (pneumoconiosis) caused by breathing in sand, osteoarthritis, a slipped disc, periodontal disease and possibly diabetes, as well as parasitic worms in her intestine and bladder. Her last years must have been full of pain and suffering. After all, what could her doctor do to help? Say a few prayers and recite a spell or two? If you read the history books, that's about as much as Asru could expect. But not according to Jackie Campbell at the KNH Centre for Biomedical Egyptology at the University of Manchester in the UK. Her research suggests that Asru's doctor probably consulted a handbook of remedies and prescribed something to soothe her cough, deaden the pain in her joints and perhaps even expel some of those worms (see "Cure of the mummy"). What's more, Campbell's findings indicate that Asru's doctor had more than a thousand years of pharmaceutical expertise to draw on. If she is right, the history of medicine needs rewriting. According to the textbooks, science-based medicine and effective pharmacy both began with the Greeks. In the 5th century BC, Hippocrates introduced rational medicine based on diagnosis and a reasoned approach to treatment. The first pharmacopoeia, De Materia Medica - a list of 600 drugs and how to acquire and prepare the ingredients - is attributed to Dioscorides in AD 50. And the "father of pharmacy" was another Greek, Claudius Galenus, who became surgeon to the gladiators in 2nd-century Rome. "The Egyptians clearly practised some medicine long before the Greeks, but much of it was thought of as fanciful and dominated by magic," says Campbell. Could such a sophisticated people really lag so far behind in such vital skills? Campbell didn't think so. The key obstacle to establishing just what the Egyptians knew about pharmacy has been translation. While the Greeks left a vast legacy of medical texts in a familiar language, we know of only 12 from the time of the pharaohs - written on papyrus in a vanished language that scholars are still grappling with. From their descriptions of diseases and treatments, the texts have left little doubt that the ancient Egyptians had considerable medical skills, but weighing up their pharmaceutical knowledge has proved trickier: although the papyri include some 2000 prescriptions, doubts surround the identity of many of the ingredients listed. Translators rely heavily on context to infer the meanings of ancient Egyptian words. "When words appear in writings on different subjects they can confirm whether the meaning they've assigned a word makes sense," says Rosalie David, director of the KNH Centre. With the prescriptions, translators rarely have that option because medicinal plants or minerals seldom crop up elsewhere. "Worse, some of the words appear only in lists and never in sentences," says David. Stuck for the right word, translators have made educated guesses, narrowing down the options linguistically before consulting a pharmacopoeia to see which ingredient had the same medicinal use and best fit the description. "If the translator was working in the 1890s, they looked up the drugs available then," Campbell says. "Later translators picked from the drugs available in their day." As a result, some 30 per cent of ingredients in the papyri were disputed. Campbell realised she would need firmer identifications before she could say how fanciful - or helpful - ancient Egyptian remedies might have been. "I'm not a linguistics expert so I used science to authenticate the prescriptions," she says. With most drugs extracted from plants, her first check was whether a plant named in a prescription grew or was traded in Egypt at the time the papyri were written. If it wasn't, she could rule it out. Fortunately, the flora of ancient Egypt is well known. Thousands of botanical specimens collected from archaeological sites are held in museums, many of them accurately dated, and some plants are illustrated in wall paintings and sculptures. Better still is the evidence from pollen grains incorporated in mud bricks or buried deep in the soil. Geological core samples have enabled archaeobotanists to reconstruct Egypt's past flora in enough detail to say what was indigenous or traded. Campbell's second approach was pharmacological: could the named ingredient have worked the way a prescription indicated? Normally, this would be the province of a forensic chemist, who would take a sample, analyse its constituents and check for biological activity. Sadly, archaeologists have yet to find any pots of ointment or neatly moulded suppositories. "But we had something better," she says. "Recipes." What the doctor ordered Although often prefaced by a prayer or spell, each prescription provides all the information needed to reproduce the remedy, from its ingredients and method of preparation right down to the dose. They follow a standard format, listing the active ingredient first, followed by stabilisers, flavourings to mask unpleasant tastes, perhaps a soothing agent to help it down and sometimes secondary drugs to alleviate the side effects of the principal drug. Last of all comes the medium, or "vehicle", in which everything is mixed. Focusing on four key papyri, which contain 1000 prescriptions and date from 1850 BC to around 1200 BC, Campbell analysed each prescription and compared it with contemporary standards and protocols. "I looked at the source of the drug and the formulation: was it a cream or an enema or a draught and so on. Then I looked at the preparation: would the active drug have been extracted appropriately? And then, could it have worked? Was the drug given the right way and in a suitable dose?" Several plants named in previous translations, such as cinnamon and aniseed, would not have worked in the ancient remedies and there is no evidence that they existed in Egypt at the time. Other plants existed but had been wrongly translated. "Some were obviously so right while others seemed improbable," says Campbell. After five years of painstaking analyses, she had compiled an ancient Egyptian pharmacopoeia listing all of the drugs in the papyri, their sources and how they were used. She had confirmed or come up with more plausible identifications for 284 ingredients - various parts of 134 species of plants, 24 animals and 28 minerals. Of the original 1000 prescriptions, she could now say exactly how 550 were made and whether they would work. For another 156, she knew all but a minor ingredient - enough to say if the remedy worked. That left 234 with unknown ingredients and 27 for which the prescription failed to identify what the drug was intended for. "We've got some of the mystery ingredients down to half a dozen possibilities. Others we'll never identify," says Campbell. The Egyptians' choice of ingredients has certainly stood the test of time. When Campbell consulted Martindale's Extra Pharmacopoeia - the 1977 edition, when drugs were still prepared in a dispensary - she found that 62 per cent of ingredients named in the papyri were still in use in the 1970s. Many still are - or at least synthetic versions of them. When preparing their remedies, the Egyptians used techniques familiar to modern pharmacists. They knew when to concentrate a drug by boiling, when to dilute it and when grinding released more of the active ingredient. They were expert in extracting drugs from plants, steeping them in either water or alcohol depending on the solubility of the active compound. "Colocynth (bitter apple), for instance, can only be extracted in mild alcohol and it always was - in either beer or wine," says Campbell. Some preparations required a two-stage extraction - first in water or alcohol and then in acid - achieved by steeping in vinegary wine or soured milk, which produces butyric acid. Most remedies were made up as required, but if they had to last longer they were preserved in sugar or alcohol. "I didn't find one drug that wasn't prepared properly," Campbell says. "I have no evidence that they were aware of the chemistry of their actions, but fortuitously or otherwise, they adopted the right techniques." The formulations stood comparison too. Checking against the 1973 British Pharmaceutical Codex, which lays down standards and protocols for making up medicines, Campbell found 67 per cent of the ancient Egyptian remedies complied, with one proviso - the Egyptians knew nothing of the need for sterility. Apart from drugs given by injection, they dispensed all the same types of medicines as we do. They had enemas, draughts and linctuses, lotions and liniments, creams, ointments and mouthwashes. They had eye drops (to be dripped through a bird's quill), pills, powders and poultices and, for gynaecological conditions, pessaries. For nasal congestion, doctors prescribed remedies to be inhaled (pour onto hot stones and breathe through a hollow reed). They were particularly adept at preparing suppositories, mixing the drug into a heavy grease and then rolling this into a pellet firm enough for insertion but which would melt at body temperature. Effective remedies So the ancient Egyptians had expert knowledge of drugs and knew the most effective ways to prepare and deliver them, but was that enough to call them pharmacists? For that, their remedies had to be effective. Ignorant of the causes of most diseases, ancient Egyptian doctors inevitably focused on symptoms. Then, as now, a soothing linctus quietened a cough whatever the cause, and a warming poultice that stimulated blood flow would relieve joint pain, whether from rheumatism or osteoarthritis. In some instances, where the cause was obvious, as with a wound or intestinal worms, the chosen drug tackled both symptoms and cause. Knowing the drug, the dose, how it was to be administered and what it was prescribed for meant it was possible to compare its effectiveness with modern remedies. Campbell was impressed. "Sixty-four per cent of the prescriptions had therapeutic value on a par with drugs used in the past 50 years. In many cases even the dosing was right." So what did Egyptian doctors prescribe? They were especially keen on laxatives, and dispensed irritants such as castor oil or colocynth, lubricants including balanites (extracted from the kernel of the desert date), or simply recommended bulk fibre, such as figs or bran. For indigestion, they prescribed an antacid of powdered limestone (calcium carbonate) where we take magnesium carbonate. For diarrhoea, doctors dispensed something to absorb water and toxins from the gut, such as kaolin or powdered carob, or a plant containing hyoscine, an alkaloid that relaxes smooth muscle and reduces gut movement. For flatulence and intestinal cramps, patients could rely on cumin and coriander - both effective antispasmodics. The discomfort of piles was eased with a suppository laced with hemp. The ancient Egyptians had effective remedies for waterborne parasites too. The most common was extract of pomegranate, which contains pelletierine, a powerful antihelminthic used until 50 years ago to get rid of tapeworms. Antimony was effective against flukes, and balanites oil, although given to soothe burning in the bladder symptomatic of schistosomiasis, would also have killed the worms that caused it. Like Asru the chantress, many people suffered from musculoskeletal disorders. The treatments were also many and varied. A patient might be instructed to rub liniment into aching joints, or bandage a warming poultice over the painful area. Extracts of mustard, juniper and frankincense or turpentine stimulated blood flow, providing warmth and enhancing the immune response. Treatments for wounds were clearly effective. Mummy studies have revealed evidence of potentially fatal injuries that had healed. Egyptian physicians treated wounds with resins and metals, both of which have antimicrobial properties, and with honey - which does not comply with modern pharmaceutical standards but nevertheless works and is increasingly used to treat ulcers and burns when antibiotics fail. By extracting water from the wound by osmosis, it makes conditions too dry for the growth of bacteria. If two-thirds of remedies were sound, what of the remainder? Some were obviously symbolic: hedgehog quills will not cure baldness, and a tap on the head with a dead fish won't do much for a migraine. Others were more a case of hope triumphing over experience: when it came to impotence, for instance, the Egyptians prescribed a remedy with 39 active ingredients - none of which would have had the slightest effect. “Hedgehog quills will not cure baldness, and a tap on the head with a dead fish won't do much for a migraine” Yet some of the odder prescriptions may turn out to be more sensible than anyone imagined. Crocodile dung as a contraceptive? There is some suggestion that, applied as a pessary, its acidity would be spermicidal. For pain relief, the papyri recommend celery seed, chewed and swallowed in alcohol. "When I began this study I thought that was one of the fanciful remedies but today celery is being investigated for its anti-rheumatic properties," says Campbell. Ancient Egyptian physicians also recommended saffron for back pain and both Crocus sativa, the source of saffron, and safflower (false saffron) are used this way in traditional medicine. Although Campbell's findings show that the ancient Egyptians were practising a genuine form of pharmacy long before the Greeks, many questions remain about how advanced it was. Campbell hopes to answer some of these in collaboration with Mohamed El-Demerdash and his team, which is working on Egypt's Conservation of Medicinal Plants Project. The project aims to re-establish and protect wild medicinal plants and to preserve the age-old knowledge of Bedouin healers. One puzzle is why both ancient prescriptions and Bedouin healers specify doses for some drugs that appear to fall below the threshold for activity. Campbell and El-Demerdash suspect that Egypt's wild-grown plants are more potent than those cultivated for conventional medicine. "Plants that grow in harsh environments synthesise more of certain active compounds to enable them to withstand the stress of drought or extreme temperature," says El-Demerdash. Analyses of plants grown by the team should resolve this. The project could also help Campbell identify some of the ingredients that still defy translation. Bedouin healers harvest the same species and make remarkably similar remedies as in pharaonic times. If Campbell is lucky, she may find they still make remedies containing some of the mystery ingredients - and for once there will be samples to analyse. On a visit to Sinai in October, Campbell ran through her pharmacopoeia with Ahmed Mansoor, a prominent local healer. "For days all I could find was similarity - nothing that I didn't know of already," she says. Before she returned to Manchester, however, Mansoor surprised her with a gift - a bag containing dung from feral donkeys that roam the mountainsides where many medicinal plants grow. "This is nature's pharmacy," he said, explaining that the Bedouin boil the dung to make a tea, which they drink as a tonic or for upset stomachs, or apply to wounds. The Egyptian papyri include half a dozen apparently irrational prescriptions based on animal dung - so did Campbell try it? "No. But I brought a sample back for analysis."

Why Bother Going Green?

transkryptome — Thu, 20 Dec 2007 17:47:41 GMT

17 November 2007 From New Scientist Print Edition PLENTY of people say it, and the rest of us probably think it as we browse the energy-efficient light bulbs, unplug our TV or leave the car and walk to the shops instead. What's the point in cutting our personal carbon footprint when more than a billion Chinese and most of the rest of the planet are jacking up their emissions as if there were no tomorrow? It's a fair question. After all, the atmosphere doesn't distinguish between a tonne of Chinese carbon dioxide and a tonne emitted by the west. As the rest of the world carries on regardless, are the paltry savings from recycling your beer cans or insulating your roof anything more than a drop in the ocean? If you just stopped trying, would the planet notice? In this special investigation, we crunch the numbers to find out whether going green is worth all the bother. First though, the big picture. Every year human activities add about 30 billion tonnes of CO2 to the atmosphere, largely through burning fossil fuels but also through destroying natural carbon sinks, such as forests. Half of this CO2 is absorbed by the remaining forests, soils and oceans, but the rest accumulates in the atmosphere. Since pre-industrial times, the concentration of CO2 in the air has risen by a little over one-third, from 270 parts per million to 380 ppm - or from 2.2 trillion tonnes to almost 3 trillion. Most scientists think it would be unsafe to let CO2 concentrations rise beyond 450 ppm - an additional 500 billion tonnes. That level would be reached by around 2040 if emissions continue at today's rates. But as developing countries industrialise, global emissions are unlikely to stay the same. Last year, China hiked its emissions by 8 per cent, or around 450 million tonnes - an increase almost as great as the UK's entire annual carbon footprint. Emissions of other large developing countries like India, Brazil and Mexico are increasing at a similar pace. Against this remorseless rise of CO2 from the developing world, can the individual actions of a few concerned westerners really make any difference? To answer this we first need to work out what our personal emissions are. That means including items omitted from the UN statistics - particularly international air travel - and the carbon footprint of goods made in foreign countries but imported for our use. When these are taken into account, the CO2 footprint of the average western European amounts to some 12 tonnes. For Americans and Australians, the figure is almost twice that, mainly because they drive more, in cars with bigger engines. In general, just under half of the emissions for which each of us is responsible come from things over which we have personal control, such as how much we drive and fly and how we heat and power our homes. Of the rest, about 25 per cent of the total arises indirectly through powering our workplaces, about 10 per cent comes from maintaining public infrastructure and government, and about 20 per cent is emitted during the production of the things we buy, including food. We can still influence some of these indirect emissions through what we buy - or we could if we had access to the right kind of information - but by and large it makes sense to concentrate on the emissions we can control directly. So how much can we realistically save and, more to the point, will it be worth it in terms of global emissions? Chris Goodall, author of How to Live a Low Carbon Life, believes so. He reckons it is possible to cut individual emissions by around 75 per cent without seriously altering our lifestyles. For a western European, that means slashing personal emissions from about 12 tonnes of CO2 to just 3 tonnes. Cutting down So how do we do it? Like charity, reducing your emissions begins at home (see Diagram). Of course, individual emissions will vary a fair bit, depending on the size of your house, how many people live in it, and how carbon-conscious you are. But a typical western home, with a total power throughput of about 20,000 kilowatt-hours per year, might generate emissions of around 5 tonnes. For each individual in the typical household this would average 2.3 tonnes, of which 1.2 tonnes is from heating the house, 0.4 tonnes from heating water and cooking, and 0.7 tonnes from general use of electricity for lighting and appliances. Many people are surprised at the importance of heating to most homes' carbon footprint, and clearly there are big hits to be made here. You can cut heating-related emissions by 40 per cent or more by replacing an inefficient old-style boiler with a condensing model, by improving house insulation, and by turning down the thermostat by 2 °C in winter. But the biggest gain here can be from installing a wood-burning stove in your living room. These are attractive features and heat the house using a renewable fuel. Such a stove could cut household emissions by 2 tonnes of CO2 per year or 0.9 tonnes per inhabitant, on average. You can halve the emissions for heating water and cooking by cutting out baths, taking short showers (no power-showers please - they are as bad as baths) and by using a microwave or pressure cooker. You can also halve electricity bills. The big four energy guzzlers in most households are refrigerators, tumble dryers, computers and lighting. Of these, the tumble dryer is the worst offender. Using it for 1 hour less per week could cut a household's annual emissions by 0.07 tonnes, and cutting it out entirely will double that saving. A computer left switched on through waking hours but turned off at night will be responsible for up to 0.4 tonnes of CO2 in a year. Switching to a laptop, which is more energy-efficient, could save you 0.2 tonnes. Switching to energy-efficient light bulbs is another smart move, saving 0.25 tonnes for a household with 25 bulbs. A digital TV set-top box on standby uses enough energy to emit 0.06 tonnes of CO2 in a year (roughly the total emissions of an average citizen of Burundi), so you can save most of that by unplugging every time you switch off the TV, and maybe half if you switch off only at night. And think about all the other kit you leave on standby. Get rigorous about unplugging every time and a typical household can save another 0.1 tonnes. It is small compared to some other savings, but significant nonetheless. A final option is to buy into green electricity tariffs. Read the small print, though, because some companies are simply asking you to subsidise what they are already obliged to do by law. In the best schemes, however, you will be helping to ensure that more wind turbines and other green sources of electricity are built. The annual carbon savings from these greener energy sources could be as much as 0.8 tonnes of CO2 per person. In the UK, road transport accounts for nearly one-sixth of a typical citizen's emissions, or about 1.8 tonnes per head. In the US, at 5.6 tonnes per head, it makes up more than one-quarter of a rather larger total. The average car there, carrying an average of 1.2 people, emits 556 grams of CO2 for every person-kilometre. A typical British car, also carrying 1.2 people, emits less than half this, at 180 grams of CO2 for every person-kilometre travelled. There are numerous ways of getting these figures down. The average American driver could save a whopping 2.5 tonnes per year by changing to a gasoline-electric hybrid car. In the UK the gains would be lower, but still significant, at 0.8 tonnes. Buying a smaller, more efficient car running on diesel or liquified petroleum gas could cut emissions by 0.4 tonnes per car per year. Turning off car air conditioning can save 0.1 tonnes, while driving moderately and at the most fuel-efficient speeds will enable some drivers to cut emissions by 0.2 tonnes a year. Another idea is to delay buying a new car. A typical car takes between 3 and 5 tonnes of CO2 to manufacture. That is twice what it typically emits in a year. So even if the new model would be more fuel-efficient, it is probably better to put off buying it. The bottom line, of course, is that we should all drive less. Getting rid of the car would be best, but is rarely practical. Sadly, cutting out short journeys to the shops does little to cut emissions. For most people it will be less than 0.1 tonnes, though cutting out a daily short journey might double that saving. Taking public transport to work makes a much more useful contribution. With every 1500 kilometres of commuting, you save 0.5 tonnes of CO2. Public transport is generally a greener option, but there are exceptions. Trains, for example, are quite variable. In the UK, the average emissions are 40 grams per passenger-kilometre (g/p-km) but, depending on the engine, the source of power and the journey, the figure varies from more than 70 g/p-km down to 27 g/p-km. So going by train is usually better, but a small, fuel-efficient car with four passengers may be more carbon-efficient than taking one of the less efficient trains. Be warned, too, that taking a sleeper train from, say, London to Edinburgh or Paris to Venice may not always be greener than flying. Sleeper cars carry fewer passengers than regular carriages, and that could push the carbon footprint of the typical sleeper passenger above that of someone flying the same route at a typical CO2 emission rate for short-haul flights of 150 g/p-km. For longer journeys, coaches such as Greyhound in the US or National Express in the UK could be just the ticket. In the UK, this would save about 140 grams per kilometre for each passenger who would otherwise have made the journey by car - the difference between the 180 g/p-km from driving a typically laden car and the 40 g/p-km on a typical coach ride - while in the US you could save 516 g/p-km. Over a 200-km drive that amounts to nearly 30 kg per trip in the UK and over 100 kg in the US. Truth about flying If you fly more than once a year, cutting back on those journeys will be the best single thing you could do to cut your emissions. Cut out that long return flight from Europe to Miami, or the US to Rome, and you have saved 2.5 tonnes of CO2 - which is probably more than you emit from your car all year. The simple truth is that frequent fliers have carbon footprints tens of times bigger than the rest of us. Thanks to abundant cheap flights, Britons are the world's worst offenders on this score, with average emissions equivalent to 1.6 tonnes of CO2 per person - more than double the rate for the average American. Cheap flights are booming in China and India too, but the annual carbon footprint for travel for average citizens in those two countries is still only around one-tenth of those in Europe and North America. Of the things we buy, food makes up about another 2 tonnes of CO2 per head. Concerned consumers often make an effort to cut their carbon footprint from food by buying locally, which reduces their "food miles". This makes some sense. A quarter of the trucks on our roads are carrying food and raw materials for the food industry. Yet many of the biggest energy inputs (and hence carbon outputs) of our food come from growing and processing food, rather than transporting it. Manufacturing fertiliser, heating greenhouses and food processing are major energy guzzlers, so buying locally is by no means automatically the greenest option. Trucking in tomatoes from sunny Spain often uses less energy than heating a greenhouse in the UK, for instance. As a rule of thumb, meat and dairy products have high carbon footprints because of the energy needed to grow the feed for the animals. Going vegetarian could halve your carbon footprint from food to 1 tonne per year, but only if you cut back on dairy products too. If you can't go without meat and milk, you could instead halve your food footprint by going organic, largely because of the saving in fertiliser. A diet made up exclusively of locally grown, non-processed and non-packaged food can strip another 0.7 tonnes from your food-based carbon footprint, bringing an impressive total saving of 1.7 tonnes per person. Drinks packaging matters too. Smelting aluminium is one of the most energy-intensive industries in the world, and making one beer or soda can emits 170 grams of CO2. That's the same as running your TV for 3 hours. The average person gets through 120 cans in a year, which adds up to 0.02 tonnes of CO2. So always recycle your cans and, for preference, buy draught beer or bottles instead. Glass's carbon footprint is rather less than aluminium's. By making these small changes, the average western European can cut nearly 8 tonnes from their personal carbon footprint, taking their personal emissions down to around 2 tonnes. Multiply that by enough people and the impact could be significant. Take the UK, for example. If just one-third of the UK population did the same it would save 160 million tonnes of CO2, or more than a quarter of the nation's emissions. Yet again, given the scale of the increases in China, India and South America, is all this effort really worth it? The answer is an unequivocal yes. Emissions reductions are a bit like taxes: you may not like them, and your individual contribution may seem too measly to matter, but multiply that by several million and you can start to move mountains. "Your contribution might not seem to matter, but multiply that by millions and you can move mountains" Scaled up to global level, these cuts become highly significant. If 100 million people in richer nations cut their CO2 emissions by 10 tonnes per year, on average, that would save a billion tonnes of CO2 emissions a year, or around 5 per cent of the current global total. That won't solve the problem on its own, but it would create space for China and India to grow their economies and their carbon emissions for another year. Then we would need to add another 100 million people for the next year. And so on and so on, until new low-carbon technologies become cheap enough for developing countries like China and India to adopt them without undermining their economic development. The global community would prefer not to allow the developing world to continue increasing their emissions indefinitely. Next month, diplomats and politicians will gather in Bali, Indonesia, to discuss what to do when the Kyoto protocol expires in 2012. Many will demand limits on the growing emissions of developing countries, including China and Indonesia, which was recently revealed to have the world's third-highest emissions - when the carbon sinks it has lost to the logging of rainforests and the draining of tropical peat swamps is taken into account. Negotiating limits for China will not be easy. It may be about even with the US as the top emitter of CO2, but divide its output by its total population and the figures look rather different. The typical Chinese citizen is responsible for less than one-quarter of the emissions of the typical American: 4.8 tonnes compared to 20 tonnes. Individual Indians and Africans have emissions averaging 1 tonne or less (see Diagram). With this in mind, a growing number of politicians are suggesting a fairer approach to cutting carbon, based not on national emissions but on setting tradeable individual carbon quotas (see "What's your quota?"). Ultimately, we will need to bring global emissions down low enough to match nature's ability to absorb them, which may be as low as 10 to 20 per cent of today's global emissions. But if a significant number of people change their ways and demand greener products, that will send a big signal to the market, encouraging the supply of green energy, low-carbon products, organic food and so on. So while it may be tempting to think that only governments can act on the scale necessary to make real change by rationing carbon and setting tax regimes to provide the necessary carrots and sticks for development, there is no escaping the fact that individuals can make a difference by acting just a little bit greener. The big picture seems daunting but it can be done. And we have to start somewhere. So don't give up. What's your quota? Much of the carbon dioxide that is warming us today has been in the atmosphere for decades, even centuries. While developed countries only contribute about 50 per cent of emissions today, they are responsible for 80 per cent of the human-made CO2 that is already there. Cutting emissions needs to be done in as fair a way as possible, and since Earth has a limited capacity to absorb CO2, one equitable solution would be to divide the remaining capacity among the world's population. Many see an idea known as "contraction and convergence" as the best way forward. This idea has been kicking around for more than a decade, but is currently most associated with a British NGO called the Global Commons Institute. If implemented, it will mean that global emissions have to contract overall, while converging on a single per-capita figure. Current emissions for a global citizen are about 4 tonnes of CO2 per year, on average. This figure will ultimately have to drop to below 1 tonne. The formula was initially dismissed as hopelessly idealistic, but it is now gaining new credibility. Most recently, the German chancellor Angela Merkel backed the idea of national targets based on per-capita emissions. Earlier this year, the UK's then environment secretary, David Miliband, took the debate one step further. He said that within a decade we could all carry a card that recorded our annual carbon-emissions entitlement. Every time we filled up our cars with fuel, booked a flight or made an energy-intensive purchase, our card would be debited. Sure, the rich would be able to buy their way out of the limits. But they would have to buy the extra carbon credits they needed for that flight to the Maldives or to light their 20 bedroom mansions. The more energy-efficient among us could make money by selling spare credits to them. At the end of the day, there would only be a certain volume of emissions allowed. And the smaller that volume, the better for all of us.

Enlightenment 2.0: Humankind Cannot Live by Rational Thought Alone

transkryptome — Thu, 20 Dec 2007 17:38:52 GMT

SCIENCE and religion: just seeing the two words in the same sentence is enough to make some people apoplectic. The commingling of the two has been one of the most contentious educational and intellectual issues of the decade. Can they live together? Can a rational person be religious? Or should scientists be campaigning to rid society of what Richard Dawkins calls these "juvenile superstitions"? To address such questions, some of the world's leading scientists met in La Jolla, California, last week for the second Beyond Belief symposium. The idea was to see how rational thinking fits with the distinctly non-rational religious beliefs that billions of people hold. Last year's meeting resounded with rallying calls from atheists determined to replace faith wherever they found it with a scientific world view. This year things were more conciliatory, with speakers recognising that we need many tools to make sense of the world besides the strictly rational (see "God's place in a rational world?"). The change of tone is welcome. While the overbearing influence of religious groups in politics, especially in the US, is worrying and needs tackling, the idea that science can simply replace religion in the public consciousness is not only fanciful, it's also bad for science. Trying to tell people how they should think is likely to alienate them. There is still a tendency among some scientists, however, to view religion as an irrational distraction and to presume that eradicating it would end a host of abuses. Witness the claim, repeated by one participant in La Jolla, that religious schools are more likely to produce extremists, and the refrain repeated ad infinitum since 9/11 that religion is a sufficient incentive for suicide bombing. Such talk should be discouraged. It is based on no evidence whatsoever. True, terrorists tend to be more educated in religion than most in their community, but they are more educated in everything. Religious education is rarely a key radicalising factor. Likewise, it has been shown over and over that the political aspirations of terrorist groups play a far more critical role in suicide bombing than religion. Moreover, religious belief is just one of many irrational human tendencies. Our sense of fairness and morality is hardly based on rational thinking. There is a growing conviction that such behaviours are largely innate, and that they evolved because they have survival value in an unpredictable world.Likewise religion. To borrow from a popular biblical saying, humankind cannot live by rational thought alone. To want to cleanse society of religion before understanding its evolutionary roots and purpose seems strangely unscientific. The problem is not with religion per se - it's with the prejudice, discrimination and backward thinking that can derive from it. The subjugation of women and opposition to condom use are good examples. Far better to tackle these issues as they arise than try to eliminate a belief system in its entirety. Does God have a place in a rational world? WE'RE on the Pacific coast, miles from southern California's still-raging wildfires, but talk of conflagration fills the air. Some of the best minds in science are gathered here at the seaside resort of La Jolla, together with some of the world's most insistent non-believers, to take a fresh look at the existence or otherwise of God. And one thing is clear: the edifice of "new atheism" is burning. The first firebrand is lobbed into the audience by Edward Slingerland, an expert on ancient Chinese thought and human cognition at the University of British Columbia in Vancouver, Canada. "Religion is not going away," he announced. Even those of us who fancy ourselves rationalists and scientists, he said, rely on moral values - a set of distinctly unscientific beliefs. Where, for instance, does our conviction that human rights are universal come from? "Humans' rights to me are as mysterious as the holy trinity," he told the audience at the Salk Institute for Biological Studies. "You can't do a CT scan to show where humans' rights are, you can't cut someone open and show us their human rights," he pointed out. "It's not an empirical thing, it's just something we strongly believe. It's a purely metaphysical entity." This is a far cry from the first "Beyond Belief" symposium a year ago, at which many militant non-believers, including evolutionary biologist Richard Dawkins and author Sam Harris, came together to hammer home the virtues of atheism (New Scientist, 18 November 2006, p 8). That gathering made much of the idea that humans can be moral without believing in God, and that science should do away with religion altogether. The mood at this follow-up conference was different. Last year's event was something of an "atheist love fest" said some, who urged a more wide-ranging discourse this time round. While all present agreed that rational, evidence-based thinking should always be the basis of how we live our lives, it was also conceded that people are irrational by nature, and that faith, religion, culture and emotion must also be recognised as part of the human condition. Even the title of this year's meeting, "Beyond Belief II: Enlightenment 2.0", suggested the need for revision, reform and a little more tolerance. Such was the message from evolutionary biologist David Sloan Wilson of Binghamton University, New York. He suggested that humans' religious beliefs may have evolved over time, thanks to the advantages they conferred as a sort of social glue holding together groups that developed them. Wilson was not saying religion is good or bad, simply that it has evolved to be hard-wired into our brains, and therefore cannot be ignored. "Adaptation is the gold standard against which reality must be judged," he said. "The unpredictability and unknown nature of our environment may mean that factual knowledge isn't as useful as the behaviours we have evolved to deal with this world." Stuart Kauffman of the University of Calgary in Canada, an expert in complex systems and the origin of life, took that argument and ran with it. No matter how far science advances, there will be aspects of nature that remain unknowable, he said. As an example, he cited Darwinian pre-adaptations - in which organisms evolve traits that end up having beneficial side effects - which are so random as to be completely unforeseeable. Fact-based knowledge can never provide all the answers, he concluded. "If we don't know what's going happen, we have to live our lives anyway... We live our lives largely not knowing. That means reason is an insufficient guide." Though Kauffman declared himself an atheist, he argued from this that it may be apt to invoke the concept of God as a proxy for such gaps in our knowledge. "I'd say that it's wise to use the word 'God'", he continued. "I know it's very freighted, but it also carries with it awe and reverence. I want to use the God word on purpose, to reinvent creativity in the natural universe. The natural universe, nothing supernatural." “I want to use the God word on purpose, to reinvent creativity in the natural universe - nothing supernatural” Chemist Peter Atkins of the University of Oxford, one of the more hard-line atheists in the room, did not let this go unchallenged. He chided fellow participants for not being sufficiently proud about what science can accomplish. Given time and persistence, science will conquer all of nature's mysteries, he said. He even proposed that atheist scientists signal their intent to do just that by adopting a flag with a Mandelbrot set as its emblem. So can scientific and religious world views ever be reconciled? Harris, author of The End of Faith, declared that they could not, and provided an uncompromising exposition on the evils of religion. Away from the meeting, philosopher Daniel Dennett of Tufts University in Medford, Massachusetts, told New Scientist that as irrational as human minds may be, calm, firm introduction of reason into the world's classrooms could over time purge them of religion. For all its fiery rhetoric, this year's Beyond Belief conference razed neither the new atheist movement nor, of course, religion itself. But it certainly lit the touch paper. An Alternative reading of literature Religion is not the only aspect of the human condition that could do with a little more rationality, said some delegates at Beyond Belief II. Jonathan Gotschall, who teaches English literature at Washington & Jefferson College in Pennsylvania, proposed marrying literary studies with a scientific style of inquiry. Gottschall has already made waves among his colleagues by conducting an experiment on how people respond to literature. From interviews with readers about their responses to books, he has shown that in general people have similar reactions to a given text. This runs counter to the conventional idea that the meaning readers take from literature is dependent more on their cultural background than what the author intended. It also appears not to make sense, as literature is grounded in subjective rather than objective experience. Gotschall, however, argues that the same can be said for literary criticism: the field is awash with irrational thought, he says, largely because most literature scholars believe that the humanities and science are distinct. As a result, literary theorists rely on opinion and conjecture, rather than trying to find solid, empirical evidence for their claims, he says. By adding an element of scientific thought to literary criticism, Gottschall says, we could unearth hidden truths about human nature and behaviour.

Buddhist Geeks: Neuroscience and The Enlightenment Machine

transkryptome — Wed, 28 Nov 2007 18:11:01 GMT

http://www.fallingfruit.tv/episodes/neuroscience-and-enlightenment-machine In this episode we spoke with neuroscientist and Buddhist meditator Daniel Rizzuto. Vince and he discussed a number of topics including the link between contemplative and scientific methodologies, some of the potential technologies that could emerge for the neuroscientific research, including Daniel's favorite, an empathic training device. Daniel also shared some of the meditation research he was aware of, including Dr. Sara Lazar's research out of harvard where she found that meditation actually affected the structural basis of the brain, as well as some of the recent meditation research that was conducted using EEG devices. We then discussed the possibility of constructing a neural map that describes a practitioners evolution, and the potential that such a map could be used to help create a device—a so called "enlightenment machine"—that could actually accelerate that process. The question soon emerged, how might this machine impact one's ethical understanding? Can someone actually go through the process without a revolution in their ethical understanding? The Buddhist tradition often describes the inseparability of insight and ethical understanding or the unity of Emptiness and Compassion. Daniel proposed that a sub-field of neuroscience, neuroethics is an attempt at understanding the neural correlates of one's ethical choices, such that this information could be built into a device even if it weren't a by-product of the process of spiritual maturation.

The Void: Imprint of Another Universe?

transkryptome — Wed, 28 Nov 2007 18:06:45 GMT

24 November 2007 From New Scientist Print Edition. Marcus Chown IN AUGUST, radio astronomers announced that they had found an enormous hole in the universe. Nearly a billion light years across, the void lies in the constellation Eridanus and has far fewer stars, gas and galaxies than usual. It is bigger than anyone imagined possible and is beyond the present understanding of cosmology. What could cause such a gaping hole? One team of physicists has a breathtaking explanation: "It is the unmistakable imprint of another universe beyond the edge of our own," says Laura Mersini-Houghton of the University of North Carolina at Chapel Hill. “Standard cosmology cannot explain such a giant cosmic hole” It is a staggering claim. If Mersini-Houghton's team is right, the giant void is the first experimental evidence for another universe. It would also vindicate string theory, our most promising understanding of how the universe works at its most fundamental level. And it would do away with the anthropic arguments that have plagued string theorists in recent years because they say we are the reason the cosmos is the way it is. The hole in the universe is a big deal. The giant void first showed up in maps of the afterglow of the big bang. In 2004, NASA's WMAP satellite made the most detailed measurements to date of the temperature of the cosmic background radiation. This microwave radiation gains a small amount of energy when it passes through a region of space populated by matter, making it appear slightly warmer in that direction. In contrast, radiation passing through an empty void loses energy, and so it appears cooler. The WMAP team noticed an abnormally large cold spot where the temperature was between 20 and 45 per cent lower than the average for the rest of the sky, suggestive of a void. The spot covers a few degrees of the sky - many times more than the full moon. However, without knowing how far away the void was, it was difficult to tell its size. Things began to change as researchers analysed the Sloan Digital Sky Survey, the largest 3D map of galaxies made so far. Once they knew how far away various galaxies were, they were able to calculate that the WMAP cold spot coincides with an enormous void that has grown to around 900 million light years across. Located about 8 billion years away, the void contains about 20 to 45 per cent fewer galaxies than you would expect. This was confirmed in August by Lawrence Rudnick, Shea Brown and Liliya Williams of the University of Minnesota in Minneapolis, who were analysing a survey of radio-emitting galaxies carried out by the Very Large Array of telescopes at the National Radio Astronomy Observatory near Socorro, New Mexico. A mere 5 per cent of the universe is filled with galaxy clusters, the other 95 per cent is mysterious voids. There are plenty of small voids, but the bigger they get the rarer they become. No one expected one 900 million light years across. A void so big is virtually impossible to explain within standard cosmology. According to our best theories, the seeds of galaxy clusters and voids were sown shortly after the big bang, when the universe was a roiling vacuum of quantum fluctuations that were then magnified by a period of superfast expansion called inflation. Fluctuations of all sizes are possible, though larges ones are rare. "Any fluctuation leading to a void as big as the WMAP cold spot is exceedingly unlikely, according to standard cosmology," says Mersini-Houghton. There are other explanations for the WMAP cold spot. For example, some researchers speculate that it is due to a giant knot in space called a topological defect, predicted in certain theoretical models (New Scientist, 13 July, p 12). However, Mersini-Houghton's explanation could have greater significance. Entangled universes She and her colleagues looked for an explanation outside of standard cosmology. They turned to string theory, the leading contender for a "theory of everything" that unites the laws of physics to explain how all matter and energy behaves. The theory holds that the ultimate building blocks of matter, such as quarks and leptons, are tiny strings of mass-energy vibrating in a 10-dimensional space-time. String theory's selling point had always been that it could make unique predictions about the properties of our universe. This made it more aesthetically pleasing than anthropic arguments, which say that certain aspects of the universe - like the constants that characterise the laws of physics - are the way they are because otherwise we wouldn't be here to wonder about them. Yet string theory does not just describe one universe. It describes 10500 universes, each one a quantum vacuum with different physical properties. So why was ours the universe that grew large? "String theorists, who so much hoped to avoid the anthropic principle, have now been forced to invoke it to explain why our vacuum was selected out from the 10500 other string vacuums," says Mersini-Houghton. Anthropic arguments leave many physicists queasy. They would prefer an explanation for the universe's properties that has nothing to do with our existence. Rather than abandon string theory completely, however, Mersini-Houghton was convinced there must be a way to thin down the forest of string vacuums without using the anthropic principle. She and her collaborator Richard Holman of Carnegie Mellon University in Pittsburgh, Pennsylvania, had a hunch that matter and gravity might have some kind of dynamic effect that whittles down the number of vacuums to a small bunch that eventually grows into our universe and its neighbours. According to string theory, each possible universe has different conditions. If a patch of vacuum is to lead to a universe like ours, the important thing is that it must grow large. This means something must oppose gravity, which tends to suck together the mass-energy of the vacuum and shrink it. That something can only be the vacuum itself. If the vacuum has an enormous negative pressure, Einstein's theory of gravity says it will generate repulsive gravity that blows rather than sucks. "A patch of vacuum's repulsive gravity therefore overwhelms the attractive gravity of its matter," says Mersini-Houghton. "For the patch of vacuum that led to our universe, this happened during the first split second of its existence in a period called inflation." According to Mersini-Houghton and Holman, the dynamic effect of matter and gravity would have weeded out the majority of string vacuums, leaving only our patch and close neighbours in the string landscape. "It's a much more scientific and legitimate way of picking out a universe like ours than the anthropic principle," she says. "But it has extraordinary consequences." Mersini-Houghton and Holman's calculations show that the patch of vacuum that led to our universe must have interacted with neighbouring patches very early on. Because these interactions are between tiny patches of quantum vacuum, they would leave the universes in an entangled state and give them a ghostly connection that allows them to sense and affect each other from afar. "Such an entangled state remains for all time," says Mersini-Houghton. "So although inflation quickly pushed our region beyond the reach of neighbouring regions, it should still retain the imprint of its quantum entanglement with its neighbours." The question is: where should we look for the imprint and what form might that imprint take? Because of the expansion of the universe, no light or signals can reach us from beyond the cosmic horizon, about 42 billion light years away. On a far smaller scale, the messy process of galaxy formation has effectively erased any trace of the early interaction between our universe and neighbouring ones. However, on scales comparable to the cosmic horizon itself, there ought to remain an imprint from the time closest to the beginning of inflation when there was an interaction. "In today's universe, it should manifest itself at a red shift of less than 1, corresponding to a time when the universe was about half its present age, says Mersini-Houghton." Smoking gun Mersini-Houghton and Holton say their dynamical theory can describe the form of the imprint too. The vacuums of neighbouring patches effectively push on our universe, they say. According to relativity, such squeezing produces repulsive gravity. Where we can see the squeezing act - on scales comparable with the size of the universe - the repulsive gravity should dramatically thin out matter and make it harder for galaxies to form. "We predict the existence of a giant void about 500 million light years across," says Mersini-Houghton. By cosmology's standards this forecast ties in pretty well with astronomers' observations of a void 900 million light years across at a red shift of 1. "We are amazed that the void is there just as we predicted," she says. Working with Tomo Takahashi of Saga University in Japan, Mersini-Houghton and Holman go further. They predict that there should be not one such giant void but two: one in the northern hemisphere corresponding to the WMAP cold spot and one in the southern hemisphere. "We are hoping that a southern void will turn up in the data soon," she says. So far the work has had a mixed reception. "It is one of the most interesting ways to relate observations in our universe to the vastly larger string landscape," says physicist Leonard Parker of the University of Wisconsin, Milwaukee. Others are more cautious. "It's interesting," says David Spergel of Princeton University. "However, it is very speculative." Mersini-Houghton and her team make a further prediction that could soon be tested - what they call the "smoking gun" of their idea. In standard cosmology, the temperature variations of the big bang radiation are the direct result of the distribution of matter in the universe. This means the pattern of galaxies should exactly match the temperature features in the big bang radiation. That won't be the case, says Mersini-Houghton. Her team's work shows that the entanglement between our universe and neighbouring universes changes the density of matter on the largest scales. If they are right, the interaction will leave a subtle mark on observations. "We predict that correlation between matter and temperature will be found to be much less than 100 per cent." The test could come as soon as next year, when the European Space Agency launches its Planck microwave background probe. Planck should be able to both confirm the existence of the cold spot and improve the precision of the WMAP sky map. Planck isn't the only test. Mersini-Houghton also makes a prediction about what will be seen - or rather not seen - at the Large Hadron Collider (LHC) near Geneva, Switzerland, when it switches on next year. Many particle physicists believe that the LHC will uncover the first experimental evidence for supersymmetry, a popular theory that posits that every particle has a heavier superpartner. None of the particle accelerators built so far has had enough energy to create supersymmetric particles, but physicists believe that the collision energy at the LHC will produce fireballs with sufficient energy to recreate conditions in the early universe. They hope to test what happened when the universe cooled below a certain temperature and underwent a phase transition, which broke supersymmetry. According to string models, the energy released during the phase transition drove inflation, and went on to create supersymmetric particles. Since the energy had to be sufficient to ensure the growth of our piece of vacuum, Mersini-Houghton and her colleagues can make an estimate of the energy scale of supersymmetry breaking. "We find it is about 100,000 times greater than generally believed," she says. "Therefore we predict that the LHC will not detect supersymmetry." String theory's saviour It is a controversial result and many physicists disagree. "The string landscape is quite dense and it is most likely that vastly different physical parameters may give rise to quite similar universes," says Orfeu Bertolami of the Instituto Superior Técnico in Lisbon, Portugal. "Nevertheless, I find their work very interesting." Despite the disagreement, the latest work is emblematic of a recent U-turn in theoretical physics. When the first WMAP results were made public in 2002, cosmologists claimed that the findings confirmed the standard model of the universe. Nobody expected anomalies to emerge and, if they did, nobody expected they would threaten to turn the standard picture of cosmology on its head. Worse, some physicists have started to turn their backs on string theory in recent years, fearing that it is a dud, incapable of making any testable predictions. Some have even gone as far as declaring string theory dead. "I think our evidence points to string theory being on the right track," says Mersini-Houghton. Now, with the discovery of the hole in the universe, it seems it could be a case of string theory is dead, long live string theory. “Our evidence points to string theory being on the right track” Is the evidence warmer? If the cosmic cold spot was all that Laura Mersini-Houghton and her colleagues had chalked up in the way of a prediction, it might be possible to dismiss it as a fluke. However, they claim they can explain two other anomalies in the WMAP measurements of the cosmic microwave background too. Both puzzles concern the way the map's pattern of temperature can be broken down into simpler components known as multipoles (see Diagram). The simplest, or "dipole", consists of one hot region and one cold region and is due to the Milky Way's motion rather than any cosmological reason. The quadrupole consists of two hot spots and two cold spots; the octupole three hot spots and three cold spots. The standard model of cosmology cannot explain why the hot and cold spots of the quadrupole and octupole are much closer in temperature than they are in other multipoles. But Mersini-Houghton says that the squeezing of our universe by neighbouring ones in her team's model leads to repulsive gravity and suppresses the quantum fluctuations that seeded matter. "This is turn depresses the temperature variations at the quadrupole scale, exactly as WMAP has seen," she says. Standard cosmology also predicts that the hot and cold spots should be randomly distributed over the sky. Yet the WMAP results appear to show a curious alignment between the quadrupole and octupole's hot and cold spots, dubbed the "axis of evil". While many cosmologists dispute the existence of the axis of evil, others have suggested its origin. The alignment might be down to our universe being smaller in one direction than in others, perhaps shaped like a CD or a ring doughnut. This would suppress temperature variations in the short direction, leading to the kind of alignment observed. Mersini-Houghton and her colleagues say their model has an axis too. It explicitly predicts that interactions between our universe and neighbouring patches should lead to correlations between matter on the largest scales. This in turn would lead to an alignment in the temperature features. Physicist Orfeu Bertolami of the Instituto Superior Técnico in Lisbon, Portugal, has also looked at the possibility of neighbouring universes interacting with each other, and is impressed with the idea. "The idea of looking for long-wavelength effects as a smoking gun of the string landscape is a quite clever one, and clearly relevant."

Sacred Geometry and Theories of Everything: The ((potential)) Link

transkryptome — Thu, 15 Nov 2007 17:52:20 GMT

http://uk.youtube.com/watch?v=-xHw9zcCvRQ 17 November 2007 NewScientist.com news service GARRETT LISI is an unlikely individual to be staking a claim for a theory of everything. He has no university affiliation and spends most of the year surfing in Hawaii. In winter, he heads to the mountains near Lake Tahoe, California, to teach snowboarding. Until recently, physics was not much more than a hobby. That hasn't stopped some leading physicists sitting up and taking notice after Lisi made his theory public on the physics pre-print archive this week (www.arxiv.org/abs/0711.0770). By analysing the most elegant and intricate pattern known to mathematics, Lisi has uncovered a relationship underlying all the universe's particles and forces, including gravity - or so he hopes. Lee Smolin at the Perimeter Institute for Theoretical Physics (PI) in Waterloo, Ontario, Canada, describes Lisi's work as "fabulous". "It is one of the most compelling unification models I've seen in many, many years," he says. That's some achievement, as physicists have been trying to find a uniform framework for the fundamental forces and particles ever since they developed the standard model more than 30 years ago. The standard model successfully weaves together three of the four fundamental forces of nature: the electromagnetic force; the strong force, which binds quarks together in atomic nuclei; and the weak force, which controls radioactive decay. The problem has been that gravity has so far refused to join the party. “For decades, physicists have been trying to find a uniform framework for the fundamental forces and particles” Most attempts to bring gravity into the picture have been based on string theory, which proposes that particles are ultimately composed of minuscule strings. Lisi has never been a fan of string theory and says that it's because of pressure to step into line that he abandoned academia after his PhD. "I've never been much of a follower, so I walked off to search for my own theory," he says. Last year, he won a research grant from the charitably funded Foundational Questions Institute to pursue his ideas. He had been tinkering with "weird" equations for years and getting nowhere, but six months ago he stumbled on a research paper analysing E8 - a complex, eight-dimensional mathematical pattern with 248 points. He noticed that some of the equations describing its structure matched his own. "The moment this happened my brain exploded with the implications and the beauty of the thing," says Lisi. "I thought: 'Holy crap, that's it!'" “The moment this happened my brain exploded with the implications. I thought: 'Holy crap, that's it!'” What Lisi had realised was that if he could find a way to place the various elementary particles and forces on E8's 248 points, it might explain, for example, how the forces make particles decay, as seen in particle accelerators. Lisi is not the first person to associate particles with the points of symmetric patterns. In the 1950s, Murray Gell-Mann and colleagues correctly predicted the existence of the "omega-minus" particle after mapping known particles onto the points of a symmetrical mathematical structure called SU(3). This exposed a blank slot, where the new particle fitted. Before tackling the daunting E8, Lisi examined a smaller cousin, a hexagonal pattern called G2, to see if it would explain how the strong nuclear force works. According to the standard model, forces are carried by particles: for example, the strong force is carried by gluons. Every quark has a quantum property called its "colour charge" - red, green or blue - which denotes how the quarks are affected by gluons. Lisi labelled points on G2 with quarks and anti-quarks of each colour, and with various gluons, and found that he could reproduce the way that quarks are known to change colour when they interact with gluons, using nothing more than high-school geometry (see Graphic). Turning to the geometry of the next simplest pattern in the family, Lisi found he was able to explain the interactions between neutrinos and electrons by using the star-like F4. The standard model already successfully describes the electroweak force, uniting the electromagnetic and the weak forces. Lisi added gravity into the mix by including two force-carrying particles called "e-phi" and "omega", to the F4 diagram - creating a "gravi-electroweak" force. Finally, he filled in most of the 248 points of the E8 pattern, using various "identities" of the 40 known particles and forces. For example, some particles can have quantum spin values that are either up or down, and each of these identities would sit on a different point. He filled the remaining 20 gaps with notional particles, for example those that some physicists predict to be associated with gravity. With the points on the E8 pattern occupied, he could rotate it using computer simulations and so project it down in various ways to two dimensions. By rotating it a certain way, he found that he could recreate the earlier basic patterns describing the quark-gluon relationship and his gravi-electroweak force. As he rotated the shape further, he found even more intriguing patterns. For example, in one configuration, you can see the gravi-electroweak interaction pattern surrounded by quarks and anti-quarks congregated into their individually "coloured" groups (visit www.newscientist.com/article/dn12891 to watch an animation of the pattern's rotation). What's more, these quarks cluster into families of three, with almost identical properties but different masses. Physicists have long puzzled over why elementary particles appear to belong to such families, but this arises naturally from the geometry of E8, he says. So far, all the interactions predicted by the complex geometrical relationships inside E8 match with observations in the real world. "As far as I have been able to tell, it's a perfect match of tens of thousands of interactions," says Lisi. "How cool is that?" Lisi is specially pleased that his model is "without strings, extra space-time dimensions or other weird inventions that there's no evidence for", which bedevil string theory. The maths is simpler, too, which he says makes it even more compelling. Compared with string theory, "this uses baby mathematics," he says. Other physicists are impressed. "Some incredibly beautiful stuff falls out of Lisi's theory," says David Ritz Finkelstein at the Georgia Institute of Technology in Atlanta. "I think that this must be more than coincidence and he really is touching on something profound." The question of why our universe should be controlled by the E8 structure is not one that Lisi tackles. "I think the universe is pure geometry - basically, a beautiful shape twisting around and dancing over space-time," says Lisi. "Since E8 is perhaps the most beautiful structure in mathematics, it is very satisfying that nature appears to have chosen this geometry." Finkelstein, however, plans to investigate whether space-time could be described as a quilt woven together from E8 patches. Sabine Hossenfelder, also at PI, argues that Lisi's idea could be complementary to string theory, rather than a radical alternative. She points out that string theorists already use E8 to describe a pattern of extra-dimensional space called the Calabi-Yau manifold, which they propose exists alongside the three dimensions that we see. "Is this a coincidence?" she asks. The crucial test of Lisi's work will come only when he has made testable predictions. Lisi himself accepts this, saying that although his theory is beautiful to him, "nature may disagree". To fill E8 entirely will require more than 20 new particles not envisaged by the standard model. Lisi is now calculating the masses that these particles should have, in the hope that they may be spotted when the Large Hadron Collider - being built at CERN, near Geneva in Switzerland - starts up next year. "This is an all-or-nothing kind of theory - it's either going to be exactly right, or spectacularly wrong," says Lisi. "I'm the first to admit this is a long shot. But it ain't over till the LHC sings."