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Related papers: Three limits to the physical world

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We consider ideal fluid and equivalent scalar field dark energy universes where all four known types of finite-time, future singularities occur at some parameter values. It is demonstrated that pressure/energy density of such…

High Energy Physics - Theory · Physics 2015-05-13 Shin'ichi Nojiri , Sergei D. Odintsov

Stars account for only about 0.5% of the content of the Universe; the bulk of the Universe is optically dark. The dark side of the Universe is comprised of: at least 0.1% light neutrinos; 3.5% +/- 1% baryons; 29% +/- 4% cold dark matter;…

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

A critical length has recently been identified that appears to provide a fundamental limit distinguishing quantum behavior from classical behavior. Because of the unique association between critical length and mass, it appears that we can…

General Physics · Physics 2007-05-23 C. L. Herzenberg

The biggest question in beyond the standard model physics is what are the scales of new physics. Ideas about scales, as well as experimental evidence and constraints, are surveyed for a variety of possible forms of new physics:…

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael Dine

Contents: 1. Introduction: Philosophical Setting 2. Quantum Model of the Mind/Brain 3. Person and Self 4. Meeting Baars's Criteria for Consciousness 5. Qualia 6. Free-Will

Quantum Physics · Physics 2008-02-03 Henry P. Stapp

Distance to Uncontrollability is a crucial concept in classical control theory. Here, we introduce Quantum Distance to Uncontrollability as a measure how close a universal quantum system is to a non-universal one. This allows us to provide…

Quantum Physics · Physics 2022-04-06 Daniel Burgarth , Jeff Borggaard , Zoltán Zimborás

The definition of physical states is the main technical issue of canonical approaches towards Quantum Gravity. In this work, we outline how those states can be found in Einstein-Cartan theory via a continuum limit and they are given by…

General Relativity and Quantum Cosmology · Physics 2016-05-06 Francesco Cianfrani

We assess how physically realistic the ''simulation hypothesis'' for this Universe is, based on physical constraints arising from the link between information and energy, and on known astrophysical constraints. We investigate three cases:…

Popular Physics · Physics 2025-04-14 F. Vazza

The properties of future singularities are investigated in the universe dominated by dark energy including the phantom-type fluid. We classify the finite-time singularities into four classes and explicitly present the models which give rise…

High Energy Physics - Theory · Physics 2009-09-17 Shin'ichi Nojiri , Sergei D. Odintsov , Shinji Tsujikawa

Geometric and topological bounds are obtained for the first energy level gap of a particle constrained to move on a compact surface in 3-space. Moreover, geometric properties are found which allows for stationary and uniformly distributed…

Quantum Physics · Physics 2024-12-23 Vicent Gimeno i Garcia , Steen Markvorsen

Is the Universe (a spatial section thereof) finite or infinite? Knowing the global geometry of a Friedmann-Lema\^{\i}tre (FL) universe requires knowing both its curvature and its topology. A flat or hyperbolic (``open'') FL universe is {\em…

Astrophysics · Physics 2009-10-31 Boudewijn F. Roukema

When a mountaineer is ascending one of the great peaks of the Himalayas she knows that an entirely new vista awaits her at the top, whose ramifications will be known only after she gets there. Her immediate goal though, is to tackle the…

Popular Physics · Physics 2010-01-20 T. P. Singh

We propose ten puzzles in particle theory: quark, asymmetries of quantum numbers in the Standard Model, point particle and interaction-distance, mystic Higgs mechanism, possible violation of the Pauli Exclusion Principle and some basic…

General Physics · Physics 2009-08-06 Yi-Fang Chang

There are at least two ways to deduce Einstein's field equations from the principle of maximum force $c^4/4G$ or from the equivalent principle of maximum power $c^5/4G$. Tests in gravitational wave astronomy, cosmology, and numerical…

General Relativity and Quantum Cosmology · Physics 2022-12-07 Arun Kenath , Christoph Schiller , C. Sivaram

It is argued that fluctuations of quantum fields in four-dimensional space do not give rise to dark energy, but are rather a negligible contribution to dark matter. By (relativistic) dark matter we mean that the relation between pressure…

High Energy Physics - Phenomenology · Physics 2011-07-18 Kimball A. Milton

The fact that the energy densities of dark energy and matter are similar currently, known as the coincidence problem, is one of the main unsolved problems of cosmology. We present here a model in which a spatial curvature of the universe…

Astrophysics · Physics 2009-11-13 Urbano Franca

In this letter, we show that quantum gravity leads to lower and upper bounds on the masses of dark matter candidates. These bounds depend on the spins of the dark matter candidates and the nature of interactions in the dark matter sector.…

High Energy Physics - Phenomenology · Physics 2021-02-03 Xavier Calmet , Folkert Kuipers

In these lectures I examine some of the principal issues in cosmology from a particle physics point of view. I begin with nucleosynthesis and show how the primordial abundance of the light elements can help fix the number of (light)…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. D. Peccei

The standard model of cosmology suggests the existence of two components, "dark matter" and "dark energy", which determine the fate of the Universe. Their nature is still under investigation, and no direct proof of their existences has…

Astrophysics · Physics 2009-07-09 A. Arbey

Some novel TWO-body effects analogous to the well-known THREE-body Efimov effect are predicted. In the systems considered, particle A is constrained on a TRUNCATED or BENT one-dimensional line or two-dimensional plane, or on one side of a…

Statistical Mechanics · Physics 2015-06-04 Shina Tan
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