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Related papers: Measure and Probability in Cosmology

200 papers

The universe we observe is homogeneous on super-horizon scales, leading to the ``cosmic homogeneity problem''. Inflation alleviates this problem but cannot solve it within the realm of conservative extrapolations of classical physics. A…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Mark Trodden , Tanmay Vachaspati

We show that most of cutoff measures of the multiverse violate some of the basic properties of probability theory when applied repeatedly to predict the results of local experiments. Starting from minimal assumptions, such as Markov…

High Energy Physics - Theory · Physics 2011-01-21 Mahdiyar Noorbala , Vitaly Vanchurin

General relativity does not allow one to specify the topology of space, leaving the possibility that space is multiply rather than simply connected. We review the main mathematical properties of multiply connected spaces, and the different…

Astrophysics · Physics 2007-05-23 Jean-Pierre Luminet

We assume a one-to-one correspondence between comoving coordinates and the cosmic rest frame in a spherically symmetric inhomogeneous universe. This strongly restricts the solutions of Einstein's equations: (i) The pressure must be zero.…

General Physics · Physics 2018-05-29 Günter Scharf

The Hubble constant sets the size and age of the Universe, and, together with independent determinations of the age, provides a consistency check of the standard cosmology. The Hubble constant also provides an important test of our most…

Astrophysics · Physics 2007-05-23 Michael S. Turner

The proper general relativistic description of the observed galaxy power spectrum is substantially different from the standard Newtonian description on large scales, providing a unique opportunity to test general relativity on horizon…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Jaiyul Yoo , Nico Hamaus , Uros Seljak , Matias Zaldarriaga

We propose a new approach for multiverse analysis based on computational complexity, which leads to a new family of "computational" measure factors. By defining a cosmology as a space-time containing a vacuum with specified properties (for…

High Energy Physics - Theory · Physics 2018-04-18 Frederik Denef , Michael R. Douglas , Brian Greene , Claire Zukowski

One of the major goals of cosmological observations is to test theories of structure formation. The most straightforward way to carry out such tests is to compute the likelihood function L, the probability of getting the data given the…

Astrophysics · Physics 2007-05-23 Scott Dodelson , Lam Hui , Andrew Jaffe

How would the world appear to us if its ontology was that of classical mechanics but every agent faced a restriction on how much they could come to know about the classical state? We show that in most respects, it would appear to us as…

Quantum Physics · Physics 2012-07-12 Stephen D. Bartlett , Terry Rudolph , Robert W. Spekkens

Understanding the behavior of the universe at large depends critically on insights about the smallest units of matter and their fundamental interactions. Inflationary cosmology is a highly successful framework for exploring these…

Astrophysics · Physics 2009-11-10 Alan H. Guth , David I. Kaiser

A new cosmological test is derived, based on the distribution of individual V/Vmax in a complete redshift-limited sample of distant objects. The fundamental assumption is that, in any bin of absolute luminosity, individual V/Vmax are…

Astrophysics · Physics 2007-05-23 L. Van Waerbeke , G. Mathez , Y. Mellier , H. Bonnet , M. Lachieze-Rey

The classical stochastic model of cosmology recently developed by us is reconsidered. In that approach the parameter $w$ defined by the equation of state $p=w{\rho}$ was taken to be fluctuating with mean zero and we compared the theoretical…

Astrophysics · Physics 2009-11-07 Moncy V. John , C. Sivakumar , K. Babu Joseph

A new formulation of quantum mechanics is developed which does not require the concept of the wave-particle duality. Rather than assigning probabilities to outcomes, probabilities are instead assigned to entire fine-grained histories. The…

Quantum Physics · Physics 2009-09-25 Andrew Gray

Quantum cosmology is the quantum theory of the entire universe. Although strange at first sight, it is appropriate because (1) our world appears to be fundamentally quantum, (2) the classical description of gravity breaks down at…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Don N. Page

In this paper, we give a possible solution to the cosmological constant problem. It is shown hat the traditional approach, based on volume weighting of probabilities, leads to an incoherent onclusion: the probability that a randomly chosen…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Artyom V. Astashenok , Antonino Del Popolo

Problem of cosmological singularity of general relativity theory is discussed. The possible resolution of this problem in the framework of inflationary cosmology is proposed. Physical conditions leading to bouncing inflationary solutions in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. V. Minkevich

Bayesian statistics is based on the subjective definition of probability as {\it ``degree of belief''} and on Bayes' theorem, the basic tool for assigning probabilities to hypotheses combining {\it a priori} judgements and experimental…

High Energy Physics - Phenomenology · Physics 2016-09-01 G. D'Agostini

We present a method to compute the probability distribution function of the (true) Hubble constant and the age of the universe, given the estimate of the Hubble constant in our nearby galaxy samples. Our method takes into account both the…

Astrophysics · Physics 2009-10-28 T. Nakamura , Y. Suto

Future measurements of primordial non-Gaussianity can reveal cosmologically produced particles with masses of order the inflationary Hubble scale and their interactions with the inflaton, giving us crucial insights into the structure of…

High Energy Physics - Phenomenology · Physics 2018-05-15 Soubhik Kumar , Raman Sundrum

Bohmian mechanics can be generalized to a relativistic theory without preferred foliation, with a price of introducing a puzzling concept of spacetime probability conserved in a scalar time. We explain how analogous concept appears…

Quantum Physics · Physics 2013-10-01 H. Nikolic