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Related papers: Astrophysical Paradoxes, long version

200 papers

In the past century many fundamental results on unpredictability, undecidability and uncertainty have compelled scientists to grapple with the idea that some questions may never be resolved within our current theories. While this…

History and Philosophy of Physics · Physics 2020-05-19 Fabien Paillusson , Matthew Booth

This paper outlines astrophysical issues related to the long term fate of the universe. We consider the evolution of planets, stars, stellar populations, galaxies, and the universe itself over time scales which greatly exceed the current…

Astrophysics · Physics 2008-11-26 Fred C. Adams , Gregory Laughlin

We review the current status of dimensions, as the result of a long and controversial history that includes input from philosophy and physics. Our conclusion is that they are subjective but essential concepts which provide a kind of…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Paul S. Wesson

The closed causal chains arising from backward time travel do not lead to paradoxes if they are self consistent. This raises the question as to how physics ensures that only self-consistent loops are possible. We show that, for one…

Quantum Physics · Physics 2007-05-23 David T. Pegg

An introductory account is given of the understanding of the structure of the universe. At present the most plausible theory of the origin of the universe is that it formed from the explosion of an extremely hot and dense fireball several…

Astrophysics · Physics 2007-05-23 H. J. Haubold , A. M. Mathai

The expansion of the Universe is the basis of modern cosmology. This chapter outlines the theory behind the expansion of the universe, including the cosmological principle, distances, velocities, and accelerations. We provide basic…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-15 Tamara M. Davis

We review a cosmology in which particles are fluctuationally created from a background Zero Point Field. This cosmology is consistent with recent observations of an ever expanding and accelerating universe, as also the recently confirmed…

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

Consider the following story: A teacher announces to her students a test for the following week, such that the test will be ``surprising''. The students use this as the basis for a ``logical derivation'' and reach a contradiction, which…

Logic · Mathematics 2026-02-04 Martin Dietzfelbinger

In this short report the first attempt of a new approach to the still mysterious phenomenon of the life, and its peak, the human being, is presented from the view point of the natural sciences, i.e. of the physics in the broad sense of the…

General Physics · Physics 2007-05-23 Boris Chirikov

The origin of the large scale structure in the universe - galaxies, quasars, clusters, voids, sheets - is one of the most important questions in cosmology. One can show that some non-thermal energy density fluctuations must have been…

Astrophysics · Physics 2007-05-23 Mairi Sakellariadou

Topological defects are produced during phase transitions in the very early Universe. They arise in most unified theories of strong, weak and electromagnetic interactions. These lectures focus on the role of topological defects in…

Astrophysics · Physics 2010-11-01 Robert H. Brandenberger

This paper is the fourth in a series whose goal is to develop a fundamentally new way of building theories of physics. The motivation comes from a desire to address certain deep issues that arise in the quantum theory of gravity. Our basic…

Quantum Physics · Physics 2008-11-26 A. Doering , C. J. Isham

In this paper, we argue that there are foundational dilemmas in theoretical physics related to the concept of reality and the nature of mathematics in physics. Physical theory is treated as a conceptual organism which develops under the…

History and Philosophy of Physics · Physics 2014-05-23 Hisham Ghassib

The expansion of the observed universe appears to be accelerating. A simple explanation of this phenomenon is provided by the non-vanishing of the cosmological constant in the Einstein equations. Arguments are commonly presented to the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-07 Eugenio Bianchi , Carlo Rovelli

Time variation of fundamental constants would not be surprising in the framework of theories involving extra dimensions. The variation of any one constant is likely to be correlated with variations of others in a pattern that is diagnostic…

High Energy Physics - Phenomenology · Physics 2014-11-17 Paul Langacker

Astronomy is a precise and relatively simple science because objects accelerate in a gravitational field at the same rate, irrespective of their composition. Galileo knew this, and Einstein took it as the basis for general relativity.…

General Physics · Physics 2013-01-03 Paul S. Wesson

Epistemic interpretations of quantum mechanics fail to address the puzzle posed by the occurrence of probabilities in a fundamental physical theory. This is a puzzle about the physical world, not a puzzle about our relation to the physical…

Quantum Physics · Physics 2007-05-23 Ulrich Mohrhoff

In this review we discuss several aspects of Cosmic Voids. Voids are a major component of the large scale distribution of matter and galaxies in the Universe. They are of instrumental importance for understanding the emergence of the Cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Rien van de Weygaert , Erwin Platen

In metaphysics, there are a number of distinct but related questions about the existence of "further facts" -- facts that are contingent relative to the physical structure of the universe. These include further facts about qualia, personal…

History and Philosophy of Physics · Physics 2018-02-06 Vincent Conitzer

Black holes are among the most extreme objects that can be found in the Universe and an ideal laboratory for testing fundamental physics. This article will briefly review the basic properties of black holes as expected from general…

General Relativity and Quantum Cosmology · Physics 2018-05-07 Cosimo Bambi