A Clash of Cosmologies

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A Clash of Cosmologies NEWS NATURE|Vol 447|10 May 2007 A clash of cosmologies Fundamentalists are threatening astronomy, dollars from astronomy in order “In the US, dark energy has done and astronomy needs to fight back. But this to measure a single ratio. more than anything else to re- time it’s not religious fundamentalists con- “A significant number of energize interest in astronomy,” vinced they already know the basic truths astronomers were being brow- says Matt Mountain, director of creation. On the contrary, it is precisely beaten,” White told Nature in an of the Space Telescope Science MAX PLANCK INST. because they lack the Universe’s basic truths interview. “I wanted to say, ‘Hey, Institute in Baltimore, Maryland. that these ‘fundamentalist physicists’ have there are different ways of think- “I think Simon is just completely mounted a crusade. They believe that astron- ing about the physical world that wrong.” omers can provide the truths they want, and are just as interesting as figur- There’s no physicist cabal they are willing to lay waste the traditions, ing out how particles and forces working against astronomers, glories and culture of astronomy to get them. interact with each other’.” adds Roger Blandford, who What’s worse, some astronomers don’t even White’s paper has quickly “The traditional directs the Kavli Institute for appreciate the threat. found a following among some of Particle Astrophysics and Cos- That, in a nutshell, is the call-to-arms issued his colleagues. “I think it’s great,” way we do mology at Stanford University, by Simon White, director of the Max Planck says Paul Schechter, an astrono- astronomy California. “I don’t see particle Institute for Astrophysics in Garching, Ger- mer at the Massachusetts Institute will cease to physics as some sort of dark force many. In a declaration appearing in this month’s of Technology. The paper stirred out there pursuing dark projects Reports on Progress in Physics, and already a lively debate at a recent journal function.” on dark subjects,” he says. nailed to the door of the popular arXiv pre- club in his department, he says, — Simon White No one denies that fundamental print server (http://arxiv.org/abs/0704.2291), and many sided with White. physicists have become increas- White warns his astronomer colleagues that “My first reaction was that there’s a lot of truth ingly involved in astronomy in recent years. “by uncritically adopting the values of an alien to this,” agrees Charles Steidel, an astrophysicist The growing entanglement is in part due to the system, astronomers risk undermining the at the California Institute of Technology in convergence of the two disciplines’ theorists on foundations of their own current success.” His Pasadena. “There’s a sort of ‘my problem is more various questions; another factor may be the treatise has been causing a stir in astronomy fundamental than yours’ mentality.” difficulty that physicists have had in moving departments and stoking animated debate on In Europe, support for White’s article appears beyond their ‘standard model’ using the tradi- various blogs. to be even stronger than it is in the United tional tools of their trade — accelerators. States. The stable, apolitical funding struc- The baryons at the gate ture in many European countries means that Number crunching White argues that astronomers are straying Europeans worry less about the latest fad, says Physicists have been prominent as designers from the true beauty of the field — the study of Georg Feulner, an astrophysicist at the Pots- and builders in projects such as the Wilkinson unusual objects in the sky — into the realm of dam Institute for Climate Impact Research in Microwave Anisotropy Probe (WMAP), which mere measurement. Particle physicists, a glam- Germany. But the United States is so powerful mapped temperature variations of the micro- orous and well financed bunch, are inveigling that many Europeans are worried about being wave background, and the Sloan Digital Sky astronomers into quantifying fundamental dragged along for the ride, says Carlos Frenk, Survey, which catalogued the galaxies across constants to satisfy the equations of cosmol- an astrophysicist at Durham University in Eng- great swathes of the heavens. ogy and high-energy physics. White is particu- land. “The US is not Kazakhstan,” he says. “It is The latest project at this junction of astron- larly damning of plans for a mission to study a driving force in astronomy.” omy and physics is the one that White por- dark energy, a mysterious force that seems to Other astronomers, however, believe that trays as the step too far. America’s Joint Dark be pushing the Universe apart. Such a project, White is both overstating physicists’ roles in Energy Mission (JDEM, joint between NASA he says, could suck hundreds of millions of the field and overlooking their contributions. and the Department of Energy) is currently a NASA/GSFC; NASA/ADEPT SCIENCE TEAM NASA/ADEPT NASA/GSFC; Three possible designs for missions to measure dark energy: SNAP, Destiny and ADEPT. 122 NATURE|Vol 447|10 May 2007 NEWS SIX DEGREES OF PHARMACOLOGY Game ranks researchers by proximity to field’s founder. www.nature.com/news HULTON-DEUTSCH/CORBIS DIGITALGLOBE DIGITALGLOBE SNAPSHOT number of trawl nets dragged behind a boat to the white dots of seabirds Ghosts of destruction flocking nearby to feast off the unwanted bycatch that is dumped overboard. A set of contrails behind close-flying jets? Orderly raking in a muddy zen This particular image was taken by the QuickBird satellite on garden? A phalanx of harvesters on a giant prairie? 20 February 2003, off the coast of Jiangsu province near the mouth of No: this is an image of shrimp trawlers (see inset) off the coast of China. the Yangtze River; ten trawlers cover each square kilometre of ocean. The long plumes of sediment churned up by their nets — ‘mudtrails’ — are Van Houtan and Pauly are now working with Quickbird, Landsat and a highly visible sign of the disturbance to sea-bottom ecosystems that other satellite data to quantify exactly how much sediment is churned up they leave in their wake. by these boats to try to get a handle on the toll taken by fishing. Repeated Conservation ecologist Kyle Van Houtan of Duke University in North trawling, they say, can permanently modify the seabed and alter the Carolina, and fisheries expert Dan Pauly of the University of British ecosystem for creatures living in the upper metres of the ocean. Columbia in Vancouver, have identified many such mudtrails in satellite “Imagining is one thing, but imaging is something else,” says Van images available through Google Earth. From the Gulf of Mexico to Houtan. “When we see an image, it really crystallizes the impacts and an Malaysia, remote-sensing imagery captures details ranging from the attitude towards the sea.” ■ competition between three differ- Steidel agrees: confirming under consideration for JDEM are a fraction ent designs for a space telescope theory is only part of what of the cost of the more general-purpose large W. KIRK that will survey thousands of astrophysicists do. “One of the telescopes being advanced by astronomers. distant supernovae. But it will do things that make astrophysics And many of the missions would collect data so not out of fascination with the interesting to people is that useful to people across the discipline. grandeur of exploding suns. Its one is almost always sur- Ultimately, Mountain says, White’s anxi- purpose is simply to gather data prised,” he says. “I think it’s ety is more nostalgia for the good-old days of on their distances and velocities as that discovery aspect of things astronomy than concern for its future. “There’s a means to improving estimates of that may suffer if resources a kind of romantic sense that a lone person dark energy’s ‘equation of state’, a are directed to answer ‘big with a telescope or a piece of paper should still ratio that is a critical parameter in “Dark energy has questions.’” be able to make breakthroughs in the field.” But cosmological calculations. Schechter adds that dark that’s not the way it works in the modern era, done more than energy, although fundamentally he warns. “The contribution of the individual A diet of wormholes anything else to interesting, is a murky concept is being lost because some of these problems Astronomers have traditionally energize interest that doesn’t have much effect are getting extraordinarily hard to tackle. The built telescopes and satellites that on stars and galaxies — the only question is: are we actually losing great allow them to study a panoply of in astronomy.” things most astronomers like science? Or are we just losing the sense that objects and that enable individuals — Matt Mountain to study. “We already know as science is as much fun as it once was?” to pursue their own ideas. In con- much about dark energy as we White stands firm in his belief that the old trast, the new mission would look more like need to know,” he says. approach needs to be preserved. “You need to a particle-physics experiment: a large team Mountain, however, counters with his keep the subject vibrant so that it attracts the of researchers would be working exclusively view that the questions surrounding dark best young people,” he says. “Otherwise the to confirm an already known theory. Such an energy are among the most important in the traditional way we do astronomy will cease to approach could ostracize the more traditional field, and are bringing welcome publicity to function.” ■ astrophysicist. astronomy. Furthermore, he says, the missions Geoff Brumfiel 123.
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