English
Related papers

Related papers: Construction of models of universe on the Riemann …

200 papers

The aim of this thesis is to question some of the basic assumptions that go into building the $\Lambda$CDM model of our universe. The assumptions we focus on are the initial conditions of the universe, the fundamental forces in the universe…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-25 Darsh Kodwani

The physical models of a successful unified theory about the Universe must operate in different phase of matter evolution and different fields of physics. The attempts to build such wide range theory as a bunch of theories developed for…

General Physics · Physics 2007-05-23 S. Sarg

We strengthen the case that the new logical perspective afforded by topos theory is suitable to the task of describing the physical world around us. In exploring some of the aspects of construction of a simple quantum-mechanical system in a…

Quantum Physics · Physics 2007-05-23 John D. Fearns

It is only human nature to be reluctant to accept something new and different. This feeling is exacerbated given the success of the Big Bang model. However, there are cogent reasons for considering this new model. Some of the advantages of…

Astrophysics · Physics 2007-05-23 J. Zzimbe

We develop a new approach to building cosmological models, in which small pieces of perturbed Minkowski space are joined together at reflection-symmetric boundaries in order to form a global, dynamical space-time. Each piece of this…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Viraj A. A. Sanghai , Timothy Clifton

It is generally argued that the present cosmological observations support the accelerating models of the universe, as driven by the cosmological constant or `dark energy'. We argue here that an alternative model of the universe is possible…

Astrophysics · Physics 2009-11-07 J. V. Narlikar , R. G. Vishwakarma , G. Burbidge

We develop a simple, fast and predictive model of the hierarchical formation of galaxies which is in quantitative agreement with observations. Comparing simulations with observations we place constraints on the density of the universe and…

Astrophysics · Physics 2009-09-25 B. Hoeneisen

There are now evidences that the cosmological constant $\Lambda$ has a non-zero positive value. Alternative scenarios to a pure cosmological constant model are provided by quintessence, an effective negative pressure fluid permeating the…

Astrophysics · Physics 2008-11-26 Antonio Vale , Jose' P. S. Lemos

We introduce "anamorphic" cosmology, an approach for explaining the smoothness and flatness of the universe on large scales and the generation of a nearly scale-invariant spectrum of adiabatic density perturbations. The defining feature is…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-02 Anna Ijjas , Paul J. Steinhardt

We construct a simple model of universe with a generalized equation of state $p=(\alpha +k\rho^{1/n})\rho c^2$ having a linear component $p=\alpha\rho c^2$ and a polytropic component $p=k\rho^{1+1/n}c^2$. For $\alpha=1/3$, $n=1$ and…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-18 Pierre-Henri Chavanis

In the framework of the Theory of General Relativity, models of stars with an unusual equation of state $\rho c^2<0$, $P>0$ where $\rho$ is the mass density and $P$ is the pressure, are constructed. These objects create outside themselves…

General Relativity and Quantum Cosmology · Physics 2018-10-03 I. D. Novikov , G. S. Bisnovatyi-Kogan , D. I. Novikov

The concept of a random Lagrangian is proposed. It is considered as a basis for a new view of the old problems such as renormalization, nonzero vacuum energy and the anthropic principle. It gives rise to nontrivial consequences both in…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. G. Rubin

Recent observations of high-redshift supernovae seem to suggest that the global geometry of the Universe may be affected by a `cosmological constant', which acts to accelerate the expansion rate with time. But these data by themselves still…

Astrophysics · Physics 2009-10-31 Idit Zehavi , Avishai Dekel

A relativistic cosmological perturbation theory for the Friedmann-Lema\^itre-Robertson-Walker universe is presented that explains the masses and formation times of the first structures in our universe. First, it is shown that, without a…

General Relativity and Quantum Cosmology · Physics 2026-04-01 Pieter G. Miedema

The basic equations describing a Newtonian universe with uniform pressure are reexamined. We argue that in the semi-classical formulation adopted in the literature the continuity equation has a misleading pressure gradient term. When this…

Astrophysics · Physics 2016-01-13 J. A. S. Lima , V. Zanchin , R. Brandenberger

We derive the Riemannian Positive Mass theorem in arbitrary dimensions, without any topological constraints. The main new tools are skin structures and surgeries on minimal hypersurfaces.

Differential Geometry · Mathematics 2016-12-23 J. Lohkamp

We show that the number of gods in a universe must equal the Euler characteristics of its underlying manifold. By incorporating the classical cosmological argument for creation, this result builds a bridge between theology and physics and…

Popular Physics · Physics 2012-04-02 Daniel Schoch

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

In the standard model of universe the increase in mass of our observed expansive Universe is explained by the assumption of emerging the matter objects on the horizon (of the most remote visibility). However, the physical analysis of the…

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

An alternative cosmological model is presented, which avoids the requirement of dark energy and dark matter. Based on the proposition that energy conservation should be valid not only locally but also globally, the energy tensor of general…

General Physics · Physics 2007-08-30 Ernst Fischer
‹ Prev 1 2 3 10 Next ›