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The Big Bounce hypothesis is a cosmological model for the origin of the known universe. It was originally suggested as a phase of the cyclic model or oscillatory universe interpretation of the Big Bang, where the first cosmological event was the result of the collapse of a previous universe. It receded from serious consideration in the early 1980s after inflation theory emerged as a solution to the horizon problem, which had arisen from advances in observations revealing the large-scale structure of the universe.
Alan Harvey Guth is an American theoretical physicist and cosmologist who is the Victor Weisskopf Professor of Physics at the Massachusetts Institute of Technology. Along with Alexei Starobinsky and Andrei Linde, he won the 2014 Kavli Prize "for pioneering the theory of cosmic inflation." Guth's research focuses on elementary particle theory and how particle theory is applicable to the early universe.
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Paul Joseph Steinhardt is an American theoretical physicist whose principal research is in cosmology and condensed matter physics. He is currently the Albert Einstein Professor in Science at Princeton University, where he is on the faculty of both the Departments of Physics and of Astrophysical Sciences.
Alexander Vilenkin is the Leonard Jane Holmes Bernstein Professor of Evolutionary Science and Director of the Institute of Cosmology at Tufts University. A theoretical physicist who has been working in the field of cosmology for 25 years, Vilenkin has written over 260 publications.
Erick J. Weinberg is a theoretical physicist and professor of physics at Columbia University.
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In physical cosmology, fractal cosmology is a set of minority cosmological theories which state that the distribution of matter in the Universe, or the structure of the universe itself, is a fractal across a wide range of scales. More generally, it relates to the usage or appearance of fractals in the study of the universe and matter. A central issue in this field is the fractal dimension of the universe or of matter distribution within it, when measured at very large or very small scales.
In physical cosmology, warm inflation is one of two dynamical realizations of cosmological inflation. The other is the standard scenario, sometimes called cold inflation.
The measure problem in cosmology concerns how to compute the ratios of universes of different types within a multiverse. It typically arises in the context of eternal inflation. The problem arises because different approaches to calculating these ratios yield different results, and it is not clear which approach is correct.
The Inflationary Universe is a popular science book by theoretical physicist Alan Guth, first published in 1997. The book explores the theory of inflation, which was first presented by the author in 1979.
The Borde–Guth–Vilenkin theorem, or the BGV theorem, is a theorem in physical cosmology which deduces that any universe that has, on average, been expanding throughout its history cannot be infinite in the past but must have a past spacetime boundary. The theorem does not assume any specific mass content of the universe and it does not require gravity to be described by Einstein field equations. It is named after the authors Arvind Borde, Alan Guth and Alexander Vilenkin, who developed its mathematical formulation in 2003. The BGV theorem is also popular outside physics, especially in religious and philosophical debates.
In physical cosmology, the graceful exit problem refers to an inherent flaw in the initial proposal of the inflationary universe theory proposed by Alan Guth in 1981.
References
- ↑ Oderberg, I. M. (2001). "A New Theory of Cosmic Origins". Sunrise. Theosophical University Press. A review of The Inflationary Universe by Alan H. Guth.
- ↑ Guth, Alan (1998). The Inflationary Universe . ISBN 978-0-201-32840-0.
- ↑ Lehners, Jean-Luc (15 August 2012). "Eternal Inflation with Noninflationary Pocket Universes". Physical Review D. Ridge, NY: American Physical Society. 86 (4): 043518. arXiv: 1206.1081 . Bibcode:2012PhRvD..86d3518L. doi:10.1103/physrevd.86.043518. S2CID 34672482.