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Related papers: The Classification of Universes

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We consider the properties of an ensemble of universes as function of size, where size is defined in terms of the asymptotic value of the Hubble constant (or, equivalently, the value of the cosmological constant). We assume that standard…

High Energy Physics - Theory · Physics 2009-11-07 James D. Bjorken

Quantum cosmology describes universe as a relativistic object with an evolution defined by an equation for the energy density corresponding to the least action principle: (Taganov, 2008). In quantum cosmology this equation plays the same…

General Physics · Physics 2008-11-26 Igor N. Taganov

The idea of a multiverse -- an ensemble of universes -- has received increasing attention in cosmology, both as the outcome of the originating process that generated our own universe, and as an explanation for why our universe appears to be…

Astrophysics · Physics 2008-11-26 G. F. R. Ellis , U. Kirchner , W. R. Stoeger

On the basis that the universe is a closed quantum system with no external observers, we propose a paradigm in which the universe jumps through a series of stages. Each stage is defined by a quantum state, an information content, and rules…

Quantum Physics · Physics 2007-05-23 Jon Eakins , George Jaroszkiewicz

In the simplest cosmological models consistent with General Relativity, the total volume of the Universe is either finite or infinite, depending on whether or not the spatial curvature is positive. Current data suggest that the curvature is…

Astrophysics · Physics 2008-11-26 Douglas Scott , J. P. Zibin

In this paper we work out a multiverse scenario whose physical characteristics enable us to advance the following the conjecture that whereas the physics of particles and fields is confined to live in the realm of the whole multiverse…

Astrophysics · Physics 2014-11-18 Pedro F. Gonzalez-Diaz , Prado Martin-Moruno , Artyom V. Yurov

The idea of a multiverse -- an ensemble of universes or universe domains -- has received increasing attention in cosmology, both as the outcome of the originating process that generated our own universe, and as an explanation for why our…

Astrophysics · Physics 2007-05-23 W. R. Stoeger , G. F. R. Ellis , U. Kirchner

Evidence for fine-tuning of physical parameters suitable for life can perhaps be explained by almost any combination of providence, coincidence or multiverse. A multiverse usually includes parts unobservable to us, but if the theory for it…

High Energy Physics - Theory · Physics 2007-05-23 Don N. Page

Many cosmological models assume or imply that the total size of the universe is very large, perhaps even infinite. Here we argue instead that the universe might be comparatively small, in fact not much larger than the currently observed…

High Energy Physics - Theory · Physics 2024-02-05 Jean-Luc Lehners , Jerome Quintin

It is proposed that spacetime should be regarded as an evolving block universe, bounded to the future by the present time, which continually extends to the future. This future boundary is defined at each time by measuring proper time along…

General Relativity and Quantum Cosmology · Physics 2015-06-22 George F R Ellis

The physical processes that determine the properties of our everyday world, and of the wider cosmos, are determined by some key numbers: the 'constants' of micro-physics and the parameters that describe the expanding universe in which we…

History and Philosophy of Physics · Physics 2018-01-23 Mario Livio , Martin J. Rees

The spacetime structure of the spatially uniformly expanding universe is described in terms of a kind of global space and global time instead of the space and time we usually recognize. The global space at some instant is a space in which…

Astrophysics · Physics 2022-08-31 Yoshio Kubo

It is now generally believed that our observable universe is one amongst a very large number - may be $10^{500}$ - of parallel universes. Following the author's own model in this context, we argue that this conglomeration of universes…

General Physics · Physics 2007-05-23 B. G. Sidharth

The global geometry of the universe is in principle as observable an attribute as local curvature. Previous studies have established that if the universe is wrapped into a flat hypertorus, the simplest compact space, then the fundamental…

Astrophysics · Physics 2009-10-30 Janna Levin , Evan Scannapieco , Joseph Silk

Scientists have measured that what we can see of space is about a billion billion billion billion billion billion billion billion billion (10^81) times the volume of an average human. Inflationary theory suggests that the entirety of space…

General Physics · Physics 2008-01-15 Don N. Page

We investigate the most general phase space of configurations, consisting of the collection of all possible ways of assigning elementary attributes, "energies", to elementary positions, "cells". We discuss how this space defines a…

General Physics · Physics 2012-06-05 Andrea Gregori

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

The assumption that a complete description of an early state of the universe does not privilege any position or direction in space leads to a unified account of probability in cosmology, macroscopic physics, and quantum mechanics. Such a…

Quantum Physics · Physics 2010-08-09 David Layzer

The Universe is the grandest conceivable scale on which the human mind can strive to understand nature. The amazing aspect of cosmology, the branch of science that attempts to understand the origin and evolution of the Universe, is that it…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-19 Tarun Souradeep

The Universe is a physical object. Physical objects have shapes and sizes. General relativity is insufficient to describe the global shape and size of the Universe: the Hilbert-Einstein equations only treat limiting quantities towards an…

Astrophysics · Physics 2007-05-23 B. F. Roukema
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