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Related papers: A cosmic hall of mirrors

200 papers

When a physicist says that a theory is fine-tuned, they mean that it must make a suspiciously precise assumption in order to explain a certain observation. This is evidence that the theory is deficient or incomplete. One particular case of…

History and Philosophy of Physics · Physics 2021-10-18 Luke A. Barnes

We briefly review the concept of a parallel `mirror' world which has the same particle physics as the observable world and couples to the latter by gravity and perhaps other very weak forces. The nucleosynthesis bounds demand that the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Zurab Berezhiani

From a modern perspective cosmology is a historical science in so far that it deals with the development of the universe since its origin some 14 billion years ago. The origin itself may not be subject to scientific analysis and…

History and Philosophy of Physics · Physics 2017-06-05 Helge Kragh

In this talk, we touch upon the chaotic and fractal aspects of the Universe.

General Physics · Physics 2015-06-26 B. G. Sidharth

Observational cosmology is on the verge of new discoveries that will change the essence of our world-view. The matter concerns origin of initial conditions and physics of dark matter.

Astrophysics · Physics 2010-11-11 V. Lukash

Some contemporary views of the universe assume information and computation to be key in understanding and explaining the basic structure underpinning physical reality. We introduce the Computable Universe exploring some of the basic…

Information Theory · Computer Science 2012-06-05 Hector Zenil

There has been a recent spate of papers on the Cosmic Horizon, an apparently fundamental, although unrecognised, property of the universe. The misunderstanding of this horizon, it is claimed, demonstrates that our determination of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Geraint F. Lewis

What do we do when cosmology raises questions it cannot answer? These include the existence of a multiverse and the universality of the laws of physics. We cannot settle any of these issues by experiment, and this is where philosophers…

History and Philosophy of Physics · Physics 2014-04-15 Joseph Silk

A new cosmological object in analogy with the concept of a wormhole in general relativity is introduced. As wormholes connect two distant points through a tunnel in spacetime, this new object connects two spacetime through a large mouth…

General Relativity and Quantum Cosmology · Physics 2022-11-28 S. Danial Forghani , S. Habib Mazharimousavi

In the past several decades, multiple cosmological theories that are based on the contention that the Universe has a major axis have been proposed. Such theories can be based on the geometry of the Universe, or multiverse theories such as…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-18 Lior Shamir

Two types of universe, with and without a center, are discussed; and their implications for the observed cmb (cosmic microwave background radiation) dipole are described. Theorems useful for understanding the cause for a cmb dipole are…

General Physics · Physics 2014-08-07 Yukio Tomozawa

Modern observations based on general relativity indicate that the spatial geometry of the expanding, large-scale Universe is very nearly Euclidean. This basic empirical fact is at the core of the so-called "flatness problem", which is…

General Relativity and Quantum Cosmology · Physics 2018-10-24 Marc Holman

Partial descriptions of the Universe are presented in the form of linear equations considered in the free (full, super) Fock space. The universal properties of these equations are discussed. The closure problem caused by computational and…

General Physics · Physics 2010-10-19 Jerzy Hanckowiak

Using recent observational constraints on cosmological density parameters, together with recent mathematical results concerning small volume hyperbolic manifolds, we argue that, by employing pattern repetitions, the topology of nearly flat…

General Relativity and Quantum Cosmology · Physics 2010-04-06 G. I. Gomero , M. J. Reboucas , R. Tavakol

Combining intervals of ekpyrotic (ultra-slow) contraction with a (non-singular) classical bounce naturally leads to a novel cyclic theory of the universe in which the Hubble parameter, energy density and temperature oscillate periodically,…

General Relativity and Quantum Cosmology · Physics 2019-07-12 Anna Ijjas , Paul J. Steinhardt

For more than a half century cosmologists have been guided by the assumption that matter is distributed homogeneously on sufficiently large scales. On the other hand, observations have consistently yielded evidence for inhomogeneity in the…

General Physics · Physics 2008-05-20 R. L. Oldershaw

Given the wealth of increasingly accurate cosmological observations, especially the recent results from the WMAP, and the development of methods and strategies in the search for cosmic topology, it is reasonable to expect that we should be…

Astrophysics · Physics 2008-11-26 M. J. Reboucas , J. S. Alcaniz

This is a written version of a talk given at the Fifth Friedmann Seminar on recent work in Observational Cosmic Topology done in partial collaboration with Armando Bernui. We address three relevant questions related to the search for the…

Astrophysics · Physics 2015-06-24 G. I. Gomero

Rich clusters of galaxies, the largest virialized systems known, provide a powerful tool for the study of cosmology. Some of the fundamental questions that can be addressed with clusters of galaxies include: how did galaxies and large-scale…

Astrophysics · Physics 2007-05-23 Neta A. Bahcall

We investigate the physics of black holes in the light of the quantum theoretical framework proposed in [1]. It is argued that black holes are completely non-local objects, and that the only one which really exists is the universe itself.

General Physics · Physics 2010-07-01 Andrea Gregori