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Related papers: Crystallography, relativity and octonions

200 papers

A consistent theory, which describes the incoherent scattering of classically moving relativistic particles by the nuclei of crystal planes without any phenomenological parameter is presented. The basic notions of quantum mechanics are…

Accelerator Physics · Physics 2021-03-05 Victor V. Tikhomirov

It seems necessary to suppress, at least partially, the formation of structure on subgalactic scales. As an alternative to warm or collisional dark matter, I postulate a condensate of massive bosons interacting via a repulsive interparticle…

Astrophysics · Physics 2009-10-31 Jeremy Goodman

If a theory has more than one classically stable vacuum, quantum tunneling and thermal jumps make the transition between the vacua possible. The transition happens through a first order phase transition started by nucleation of a bubble of…

High Energy Physics - Theory · Physics 2015-05-26 Ali Masoumi

We study cosmological effects of homogeneous tachyon field as dark energy. We concentrate on two different scalar field potentials, the inverse square potential and the exponential potential. These models have a unique feature that the…

Astrophysics · Physics 2008-11-26 H. K. Jassal

This note gives a uniform, self-contained, and fairly direct approach to a variety of obstruction-theoretic problems on 8-manifolds. We give necessary and sufficient cohomological critera for the existence of almost complex and almost…

Algebraic Topology · Mathematics 2008-10-29 Martin Cadek , Michael Crabb , Jiri Vanzura

The existence and detection of scalar fields could provide solutions to long-standing puzzles about the nature of dark matter, the dark compact objects at the centre of most galaxies, and other phenomena. Yet, self-interacting scalar fields…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Pau Amaro-Seoane , Juan Barranco , Argelia Bernal , Luciano Rezzolla

We propose a gravitational theory in which the effective Lagrangian of the gravitational field is given by an arbitrary function of the Ricci scalar, the trace of the matter energy-momentum tensor, and the contraction of the Ricci tensor…

General Relativity and Quantum Cosmology · Physics 2014-12-30 Zahra Haghani , Tiberiu Harko , Hamid Reza Sepangi , Shahab Shahidi

With the aid of a Fermi-Walker chart associated with an orthonormal frame attached to a time-like curve in spacetime, a discussion is given of relativistic balance laws that may be used to construct models of massive particles with spin,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Robin W. Tucker

Cosmological perturbations with wavelengths smaller than Hubble radius can be handled in the context of Newtonian theory with very high accuracy. The application of this Newtonian approximation, however, is restricted to nonrelativistic…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ali Nayeri , T. Padmanabhan

Relativistic, scalar particles are considered, contained in a box with periodic boundary conditions. Although interactions are not expected to be a fundamental problem, we concentrate on free particles. By considering them to be harmonic…

Quantum Physics · Physics 2023-06-19 Gerard t Hooft

This paper is devoted to an interaction of 2 objects: the 1st of them is octonions, the classical structure of pure mathematics, the 2nd one is Mobilevision, the recently developped technique of computer graphics. Namely, it is shown that…

High Energy Physics - Theory · Physics 2016-09-06 Denis Juriev

When gravity is quantum, the point structure of space-time should be replaced by a non-commutative geometry. This is true even for quantum gravity in the infrared. Using the octonions as space-time coordinates, we construct a pre-spacetime,…

General Physics · Physics 2022-09-08 Tejinder P. Singh

We construct the vector fields associated to the space-time invariances of relativistic particle theory in flat Euclidean space-time. We show that the vector fields associated to the massive theory give rise to a differential operator…

High Energy Physics - Theory · Physics 2007-05-23 W. F. Chagas-Filho

Based on the concept of curved spacetime in Einsteinian General Relativity, the field theories and their quantum theories in the curved octonion spaces etc are discussed. The research results discover the close relationships of the curved…

General Physics · Physics 2011-11-10 Zihua Weng

Any metric theory of gravity whose interaction with quantum particles is described by a covariant wave equation is equivalent to a vector theory that satisfies Maxwell-type equations identically. This result does not depend on any…

General Relativity and Quantum Cosmology · Physics 2014-04-30 Giorgio Papini

It is shown that the accelerated expansion of the universe in the framework of the relativistic theory of gravitation can be achieved by the introduction of the quintessential term in the energy-momentum tensor. The value of the minimum…

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

Given that the dark matter and dark energy in the universe affect cosmological observables only gravitationally, their phenomenology may be described by a single stress energy tensor. True unification however requires a theory that…

Astrophysics · Physics 2008-11-26 Dimitrios Giannakis , Wayne Hu

The condensed matter analogs are useful for consideration of the phenomena related to the quantum vacuum. This is because in condensed matter we know physics both in the infrared and in the ultraviolet limits, while in particle physics and…

General Relativity and Quantum Cosmology · Physics 2025-11-11 G. E. Volovik

Entanglement entropies have revealed, in the last years, to be a powerful tool to extract information about the physics of condensed-matter systems. In the first part of this thesis, we show how to extract essential details about the…

Strongly Correlated Electrons · Physics 2013-09-17 Luca Taddia

Space-time symmetries and internal quantum symmetries can be placed on equal footing in a hyperspin geometry. Four-dimensional classical space-time emerges as a result of a decoherence that disentangles the quantum and the space-time…

Quantum Physics · Physics 2007-05-23 Dorje C. Brody , Lane P. Hughston