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Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its origin, structure, evolution, and ultimate fate. Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed those physical laws to be understood.
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In physical cosmology and astronomy, dark energy is an unknown form of energy that affects the universe on the largest scales. Its primary effect is to drive the accelerating expansion of the universe. Assuming that the lambda-CDM model of cosmology is correct, dark energy is the dominant component of the universe, contributing 68% of the total energy in the present-day observable universe while dark matter and ordinary (baryonic) matter contribute 26% and 5%, respectively, and other components such as neutrinos and photons are nearly negligible. Dark energy's density is very low: 6×10−10 J/m3, much less than the density of ordinary matter or dark matter within galaxies. However, it dominates the universe's mass–energy content because it is uniform across space.
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In cosmology, primordial black holes (PBHs) are hypothetical black holes that formed soon after the Big Bang. In the inflationary era and early radiation-dominated universe, extremely dense pockets of subatomic matter may have been tightly packed to the point of gravitational collapse, creating primordial black holes without the supernova compression needed to make black holes today. Because the creation of primordial black holes would pre-date the first stars, they are not limited to the narrow mass range of stellar black holes.
The Hans A. Bethe Prize, is presented annually by the American Physical Society. The prize honors outstanding work in theory, experiment or observation in the areas of astrophysics, nuclear physics, nuclear astrophysics, or closely related fields. The prize consists of $10,000 and a certificate citing the contributions made by the recipient.
Uroš Seljak is a Slovenian cosmologist and a professor of astronomy and physics at University of California, Berkeley. He is particularly well-known for his research in cosmology and approximate Bayesian statistical methods.
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References
- ↑ Van Duch, Margaret (April 2, 1995). "Head of the Class". Chicago Tribune.
- ↑ "Caltech senior heads for graduation with 4.2 GPA, record of leadership, and is only 18". Caltech News. 13 June 2001.
- ↑ Weak gravitational lensing theory and data analysis / Christopher Michael Hirata - Princeton University Library Catalog – via catalog.princeton.edu.
- ↑ "Ohio State Researcher Wins Top Prize for Young Astronomers". 31 January 2014.
- ↑ Tseliakhovich, Dmitriy; Hirata, Christopher (2010). "Relative velocity of dark matter and baryonic fluids and the formation of the first structures". Physical Review D. 82 (8): 083520. arXiv: 1005.2416 . Bibcode:2010PhRvD..82h3520T. doi:10.1103/PhysRevD.82.083520. S2CID 32436298.
- ↑ "Breakthrough Prize – Fundamental Physics Breakthrough Prize Laureates – Christopher Hirata". breakthroughprize.org.
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