preliminary rough translation by babelfish
Out!
Physics is in the crisis: The dream of the world formula burst, the new theories is hardly more examinable. Does it at all still concern in the cosmology science?
by Max Rauner
Free love, LSD, anti-war demo. Leonard Susskind took part in all that "and still more", as he stresses. Afterwards it became a physics professor at the American elite university Stanford, in the heart remained it a rebel. Now Susskind wrote a book, which shifts its colleagues in riot. If it keeps right, is physics at the end. Or completely at the beginning.
Originally Susskind was taken off to find the world formula a all-comprehensive theory, which describes the Big Bang just like the nano-world. For a long time it waehnte itself close to. With the most brilliant physicists and mathematicians he developed the stringer theory in the eighties, the best candidates for a world formula. Before six years the hope of the physicists got a first tear, when it showed up that this theory supplies many solutions almost infinitely. Now Susskind Ernst makes: In its book it postulates The Cosmic Landscape the fact that the theoretical solutions are not an excrescence of mathematics but to material in each case would correspond existing university verses.
However would be called: There are innumerable other worlds beside our well-known universe – and in everyone this own laws of nature apply for university verses. Thus however the search according to the world formula would be led ad absurdum. More badly still: Whether actually it exists to other university verses or not, leaves itself practically to never examine. And then the question arises whether such a physics can be considered at all still as natural science.
No miracle that among physicists a violent discussion was inflamed. In the controversy it goes over the relationship of theory and reality, over coincidence and necessity, physics and Metaphysik. Go around exploding, shrinking, and one on the other hitting worlds – and around the question whether the physicists have still all cups in the cabinet
To the cosmological offense now a heavy depression comes
Cosmological principle debates shook always also the self understanding of humans. Before 500 years Nikolaus Kopernikus fell the geocentric conception of the world and set the sun into the center of the universe. Driving out of the navel of the world described Sigmund Freud later than "cosmological offense" of mankind. Soon it became clear that the sun is only one star in the backyard of the Milky Way and the Milky Way only one of but billions other galaxies in the universe. The fact that the physicists doubt now also still the however position of our universe appears there only consistent.
According to Susskind we live "in an infinitely small bag in an enormous Megaversum". Our world would be therefore only a kind philanthropic niche, besides however gives it innumerable other university verses. Some of them are empty and boring, others exist for a few milliseconds, a hand fully stars, planets and even lives brought out. This conception of a multi or mega+verse around gives it of course longer. New it is however that meanwhile not only a few philosophically inspired crank in it believe, but to a certain extent the guidance elite of theoretical physics. Leonard Susskind, and other one with it, is anyhow safe itself: If philosophers and physicists look back in one hundred years, they will describe the today's time as that period, in which the concept of the only universe was replaced in favor of the conception one multi-verse around.
But if Kopernikus’ Theory an offense was, is the Multiversum a heavy depression. Thus mankind would pull itself back on a completely insignificant, coincidental island in the cosmic ocean. Us only the comfort remains that there are nevertheless organisms on this island, which are intelligent enough to argue about it.
Scientifically seen, that is hauptproblem of this conception however their examinableness: From where are we to know whether the theory of the multiple worlds is actually correct? Even if there were many other university verses really, we could never throw a view of it. Still is science? Or does physics thereby approach the Esoterik, in which much is only maintained, but nothing proven or refutable is? The philosopher Karl Popper set up once to the maxim that scientific theories should be so constituted that one disproves it in principle, therefore falsifizieren can. If one gives this guiding principle up, a grundpfeiler of the natural science comes into the wanken.
The criticism at Susskinds theses is accordingly hard. "I consider the beginning dangerous", say Paul Steinhardt of the Princeton University. "the science would come to a depressing end." The stringer theoretician Brian Greene feared, the idea can hold scientists to look for more deeply lying explanations. And the cosmologist Lee Smolin of the perimeter of institutes in Waterloo, Canada, grumbles: "Lenny Susskind errs, and he will see that he errs." One can present gladly ideas, "however if one a theory has, which predicts neither something avowedly nor something, then stops one making science."
But the multi-verse around theory has just as prominent advocates. "our whole universe is a fruitful oasis within multi-verse around", says the astrophysicist Sir Martin Rees, president of the venerable British Royal Society. Andrei lime tree of the Stanford University, to which its colleagues sometimes with charm-cheat maintains, already simulated the Multiversum on the computer and placed pictures of it on its Website ("Kandinsky Universen"). Even the Nobelpreistraeger steven vineyard, a solid, highly estimated theoretician, shows up openly. "I am not convinced yet of the Multiversum, but I take the possibility seriously."
The controversy was overdue. Because with all success physics to today no answer to the fundamental question has: Why is the world straight so constituted, how we find it? Or, in the words of Einstein: "could God have created the world also differently?" In the meantime we know that laws of nature and natural constants are so finely adjusted that the smallest deviations would have fatal consequences, anyhow for the existence of humans. But an explanation of this be astonished-worth phenomenon physics did not come more near.
Until today two large theories stand next to each other like marriage partners, who sleep in separate beds: _ Einstein relativity theory and the quantum theory. With the one can one space, time and cosmological structures compute, with the other one the behavior of atoms and elementary particles. Both are extremely efficient in their range, but they do not find simply to each other. In the Big Bang they fail, too extremely are conditions in the Big fear for. And why light is fast approximately 300000 kilometers per second and a hydrogen atom weighs straight 1.67 time 10-27 gram, the theories cannot explain also. Dozens of such natural constants must insert the physicists quasi by hand into the equations.
"as young physicists hoped I to find beauty and elegance in the laws of nature", remembers Leonard Susskind. As his father as plumbers shifted the pipes, right-angled, parallel, somehow aesthetically, then he imagined physics. "instead I found a depressing disorder." That was end of the sixties. In the seventies the situation improved, in the Achtzigern became the physicists euphorically. A new theory made hope, it for them described elementary particles no longer than punctiform particles, but than swinging strings or threads. These stringers are too small, in order ever directly to be observed to be able (approximately 10-33 centimeters), but with this trick could mathematical infinities in the equations be avoided. Even the gravitation strength from relativity theory found its place in the abstract thought building. So far however the stringer theory is so complicated that many characteristics lie multi-verse around in the dark. For example it postulates eleven dimensions, by which some are microscopically "rolled up", so that we notice only three space dimensions.
Michio Kaku compares the stringer theory in its new book in the parallel universe with a small, beautiful pebble, which the physicists find with a migration by the desert: "as we the sand aside sweep, state we that it concerns in reality the point of an enormous pyramid, which lies buried under tons by sand. After decades we discover mysterious hieroglyphics, hidden chambers and tunnels. A daily we will penetrate on the lowest level and the gate will finally up-push."
Which formulates Kaku so blumig, is the dream of the world formula. But that is now burst – says Susskind, which in the meantime a white beard and a Halbglatze decorate: "the beauty became the beast." After Susskinds computations the stringer theory has at present 10500 solutions, which is practically infinite. Until Susskinds appears book The Cosmic Landscape on German, still some powers of ten at university verses could come. Instead of talking from a pyramid to, the Stanford professor sketches now the picture of a boundless imaginary landscape, which our cosmos same. In this landscape there are mountains, valleys and hochebenen. And in each valley another universe lies. Some look like ours, most exist only briefly, before in the valley again a new universe is born. Only unfortunately: One does not come from a valley into the other one. Whether actually exist to possible other university verses, one can never determine.
Such not examinable theories drive the physicist Lee Smolin the cold sweat on the forehead. If physics gives the principle up of the examinableness, then Smolin warns, comes it into the proximity of religious theories as for instance the creation teachings of intelligently the Design. "the danger lies directly before our entry door", says Smolin. The catholic church again the many world theory is not religion compatible enough. Thus the Viennese cardinal Christoph beautiful fount geisselte with his much considered attack on the evolution theory in the past year explicitly also the hypothesis of the Multiversum. It contradicts the overwhelming vouchers for purpose and Design of nature.
If there are sufficient university verses, one of it must be habitable
Hard-boiled physicists such as Steven Weinberg leave such church attacks cold. "it is beautiful that cosmology is now also getting a little of the attention, which evolution theory enjoys these days" comments Weinberg (the expression of beautiful sounds sarcastic. Straight one on atheistisch gesinnte scientists such as Weinberg exercises the speculative thesis of the Multiversum a special attraction. They struck themselves so far in vain with the question around, to bring out why the cosmos seems as created, in order stars, planets and sometime also intelligent life. The almost unbelievable fine tuning of the natural constants in favor of a habitable universe dissolves in the multi-verse around theory however in well-being favours. According to it the existence of a philanthropic universe is a pure consequence of the statistics: Under 10500 university verses must be simple ours thereby, six correct ones as somebody in the Lotto taps, if enough people along-play. Martin Rees compares the Multiversum with a large dress business. "if the selection of dresses enough is large, is not not surprised we to find something fitting" – indeed our own universe.
Could God have created thus the world also differently? Yes, the multi-verse around theoreticians answer and set still one drauf: It used its clearance extensively. Stupidly only that this conception leads to an almost inflationary arbitraryness in the description of the reality.
How thus does it continue in physics? Who not so that contently give may myself the fact that either our universe is pure coincidence or the dear God has all straight so hang-curved, as we find it, has the choice between three possibilities.
The principle hope. Finally is the stringer theory still for a long time not finished, perhaps the physicists somewhat surveyed. "it is much too early, to give up", says Princeton professor Paul Steinhardt, who set up its own theory of an eternally returning, cyclic universe. Who knows, perhaps still everything turns to the good one at the end, and an extended stringer theory describes a daily exactly a universe, i.e. ours.
The escape forward. We existed really accept, the Multiversum. Then are appropriate for other university verses outside of our own, and even the best telescope could never see it. Perhaps but other forecasts can be derived from the theory, which one could examine a daily, at least in our universe, empirically. At the European research lab CERN in Geneva 2007 the Large hadron Collider (LHC) is to go into enterprise. Perhaps this gigantic particle accelerator finds a reference to the hidden space dimensions, which the theory predicts.
Finally the possibility of the mistake remains. "the stringer theory is simply and simply wrong", believes for example Peter Woit. The mathematician of the Columbia University in New York operates the anti-stringer Web log emergency even wrong and demands: "a correct theory should have a limited number of solutions." As alternative candidates for such a theory some researchers discuss the loop quantum gravitation in such a way specified, which is developed among other things at Albert-Einstein-Institut in potsdam. According to it space-time from tiny pellets is developed. It gets along without the many dimensions and university verses of the stringer theory. The problem is bare: Also this theory supplies so far no empirically examinable forecasts.
After 2500 years physics seems again arrived at the beginning
German physicists play almost no role in the heated debate over the Multiversum. Perhaps the Sozialisation of the Bronx is missing to them, where Leonard Susskind and Steven Weinberg attended the same High School. But in this country philosophical analysis is maintained. R. Hedrich of the University of Giessen got a request at the German research council granted, in order to arrange the arguments of the physics debate. Who calls the philosopher, classical music in the background hears. "the theory of the Multiversum is reasonable in its logic", says Hedrich, "however not reasonably enough to be around science." The research program reminds it of that the Vorsokratiker in the old Greece: It is "metaphysical thinking about nature".
Did physics arrive with it after 2500 years again with its beginnings? Lee Smolin, joint founder of the loop quantum gravitation, swears to its colleagues not to go to the multi-verse around theory on the glue: "the progress of the science in the last 400 years is based on a few ethical basic rules, and Falsifizierbarkeit is one of it." One must absolutely maintain Poppers requirement of the refutableness in principle. Leonard Susskind is there fundamental different opinion: "follows property scientific practice no abstract set of rules, which for us a few philosopher prescribes, maintains" he in a hostile exchange with Lee Smolin on the Website edge.org. Smolin plays itself like an arbitrator over good and bad science up. "the natural science is the horse, which pulls the truck of philosophy. Do not let us the truck before the horse stretch."
Smolin has by the way its own theory of the universe. University verses could come as baby university verses in black holes to the world and afterwards a kind Darwin selection process subjected be. That is even refutable, insures Smolin, by the observation of neutron stars so mentioned. But again different researchers doubt that.
"Hypothesis non fingo", said Newton, I make no hypotheses. His current professional colleague is less restrained. It almost seems as if inventing new universes serves as pastime, or a kind of finger exercise, until the LHC finally starts operating. However, simply to dismiss the bizarre world-pictures of the cosmologists and stringer theoreticians however simply as craziness would be too easy. "As long as no one has a better idea, one must keep trying this," says the Giessener philosopher of Reiner Hedrich, even if the premise seems paradoxical, "trying out, even knowing that it doesn't work this way."
Until the cosmologists have again firm soil under the feet, one will have to be content provisionally with another measure for the reliability of a theory: Royal Society president Martin Rees would BET HIS DOG on the thesis of the Multiverse, and Andrei Linde of Stanford University would even bet his life. And Steven Weinberg announced in November in an essay with the title Living in the Multiverse, he has already has enough confidence in the theory, "to bet both Andrei Linde's life and Martin Rees’ dog on it".
THE TIME 26.01.2006 NR.5
05/2006