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The emergent universe scenario is a proposal for resolving the Big Bang singularity problem in the standard Friedmann-Lemaitre-Robertson-Walker cosmology. In the context of this scenario, the Universe originates from a nonsingular static…

General Relativity and Quantum Cosmology · Physics 2021-07-14 Elham Ghorani , Yaghoub Heydarzade

Loop quantum cosmology is an application of recent developments for a non-perturbative and background independent quantization of gravity to a cosmological setting. Characteristic properties of the quantization such as discreteness of…

Astrophysics · Physics 2009-11-13 Martin Bojowald

The physical instability of the Universe model with de Sitter beginning is proved in this article. 1. It is shown that even a small addition of ultrarelativistic matter turns the de Sitter Universe into the Universe with finite past. 2.…

General Relativity and Quantum Cosmology · Physics 2015-08-24 Yurii Ignat'ev

We consider a non singular origin for the Universe starting from an Einstein static Universe in the framework of a theory which uses two volume elements $\sqrt{-{g}}d^{4}x$ and $\Phi d^{4}x$, where $\Phi $ is a metric independent density,…

General Relativity and Quantum Cosmology · Physics 2013-06-24 E. I. Guendelman

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

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

Oscillating solutions to the effective equations of Loop Quantum Cosmology have been suggested for the role of an `eternal seed', providing a possible starting point for the emergent universe scenario. We investigate the stability of a…

High Energy Physics - Theory · Physics 2015-06-19 Audrey T. Mithani , Alexander Vilenkin

General Relativity traces the evolution of our Universe back to a Big Bang singularity. To probe physics before the singularity -- if indeed there is a ``before'' -- we must turn to quantum gravity. The Causal Set approach to quantum…

General Relativity and Quantum Cosmology · Physics 2021-09-27 Bruno Valeixo Bento , Stav Zalel

We propose a cosmological model in which the universe undergoes an endless sequence of cosmic epochs each beginning with a `bang' and ending in a `crunch.' The temperature and density are finite at each transition from crunch to bang.…

High Energy Physics - Theory · Physics 2009-11-07 Paul J. Steinhardt , Neil Turok

If we look from a quantum perspective, the most natural way in which the universe can be created is in entangled pairs whose time flow is oppositely related. This suggests the idea of the creation of a universe-antiuniverse pair. Assuming…

General Relativity and Quantum Cosmology · Physics 2025-09-29 Naman Kumar

It has been proven recently that the Standard Model of particle physics has electric charge quantization built into it. It has also been shown by the author that there was no electric charge in the early universe. Further it is shown here…

Astrophysics · Physics 2007-05-23 Afsar Abbas

Assuming that the universe is a system obedient to known thermodynamic laws and equations, here we explore whether it is a possibility for the universe to exist and evolve without any cosmic structure or force necessarily emerging within…

General Physics · Physics 2007-05-23 Akinbo Ojo

Massive gravity is a modified theory of general relativity. In this paper, we study, using a method in which the scale factor changes as a particle in a "potential", all possible cosmic evolutions in a ghost-free massive gravity. We find…

General Relativity and Quantum Cosmology · Physics 2013-03-21 Kaituo Zhang , Puxun Wu , Hongwei Yu

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

We contrast the possibility of inflation starting a) from the universe's inception or b) from an earlier non-inflationary state. Neither case is ideal since a) assumes quantum mechanical reasoning is straightforwardly applicable to the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 D. H. Coule

We "explain", using a Classical approach, how the Universe was created out of "nothing", i.e., with no input of initial energy nor mass. The inflationary phase, with exponential expansion, is accounted for, automatically, by our equation of…

General Physics · Physics 2010-12-14 Marcelo Samuel Berman

We survey some of the philosophical challenges and pitfalls within origins research. Several of these challenges exhibit circularities, paradoxes, or anthropic biases. We present origins approaches in terms of three broad categories:…

Popular Physics · Physics 2023-03-15 Stuart Bartlett , Michael L Wong

If our universe underwent inflation, its entropy during the inflationary phase was substantially lower than it is today. Because a low-entropy state is less likely to be chosen randomly than a high-entropy one, inflation is unlikely to…

General Relativity and Quantum Cosmology · Physics 2011-05-12 Sean M. Carroll , Jennifer Chen

How did it all begin? Although this question has undoubtedly lingered for as long as humans have walked the Earth, the answer still eludes us. Yet since my grandparents were born, scientists have been able to refine this question to a…

Astrophysics · Physics 2007-05-23 Max Tegmark

Within the framework of an eternal inflationary scenario, a natural question regarding the production of eternal bubbles is the essential condition requires to have a universe capable of generating life. In either an open or a closed…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 Sohrab Rahvar
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