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The Inflationary Universe. By Josh Heller Sarah Breid Jesse Zellmer. Inflation Theory-.
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The Inflationary Universe By Josh Heller Sarah Breid Jesse Zellmer
Inflation Theory- The phenomenon by which the universe is driven into exponential expansion by the repulsive gravitational field created by a false vacuum. Inflation would end with the decay of this false vacuum. Although the inflation would occur in far less than a second, it could account for the “bang” of the “big bang theory”, it could explain the origin of essentially all of the matter in the observed universe, and it can solve the horizon problem and the flatness problem. It could also generate the density perturbations that would later become the seeds for galaxy formation.
Alan H. Guth Alan H. Guth is V.F. Weisskopf Professor of Physics at the Massachusetts Institute of Technology. In addition to receiving many distinguished academic awards, Newsweek has called him one of "The 25 Top American Innovators," and Science Digest has ranked him among the "100 Brightest Scientists Under 40." He lives in Brookline, Massachusetts, with his wife and two children.
Alan Guth and inflation The classic big bang theory is great at describing what happened after the bang. Yet until recently, particle physicists and cosmologists were stuck on many questions that the big bang theory couldn't answer, including: What made the big bang BANG in the first place? If matter can be neither created nor destroyed, how could so much matter arise from nothing at all? Why can we only see a minute part of the mega-universe? In 1979, a young particle physicist named Alan Guth answered these questions and made front page news with one of the greatest discoveries in modern cosmology: cosmic inflation. This is the compelling, first-hand account of Guth's paradigm-breaking discovery of the origins of the universe; and it is a fascinating chronicle of his dramatic struggle to justify it.
Why the theory of inflation is needed There are gaps in the Big Bang theory about how all the matter exploded into what is now the universe. Inflation expands upon the theory and describes what was happening before the Big Bang.
Inflation begins Inflation not only explains the uniformity that we see in the cosmic background radiation, but it also explains the statistical properties of the very faint nonuniformities that have been observed with instruments so sensitive that they can measure minute variations of less than 1/1000 of a percent.
The old theory In the early 1900's Edwin Hubble noticed that not only are most galaxies are red-shifted (meaning that they are moving away from us, but that the ones further away from us (with light from much further back in time) were moving faster than those moving closer to us. Crunching the numbers from this he concluded that everything was expanding away from each other at a steady rate, and had been doing so as far back as one could see. Not only were the galaxies moving apart from each other, but space itself was getting bigger. So if you went back far enough in time, everything would be very, very close together
Old theory continued And if everything were very, very close together things would get very very dense, very very hot, and particles would be very very energetic. So energetic, in fact, that if you go far enough back, we haven't observed things with those energies, so our laws of physics don't cover what happened if we go back too far - we have to make educated extrapolations. But before that happens, other weird things happen, like it becomes too hot for atoms to hold together, or the forces of electricity and magnetism start acting like the forces that hold atomic nuclei together. This very early time period, is governed by laws of a branch of physics called particle physics, which is related to quantum mechanics.
Big Bang and Inflation The inflation theory builds on particle physics and gets its name by concluding that during the earliest period of the universe's expansion, it wasn't expanding at a steady rate, but had an accelerating rate of expansion - i.e., things started expanding slowly but sped up. Then, after not terribly long things had a steady rate of expansion.