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Related papers: Why 3 + 1 metric rather than 4 + 0 or 2 + 2?

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The phenomenologically observed flatness - or near flatness - of spacetime cannot be understood as emerging from continuum Planck (or sub-Planck) scales using known physics. Using dimensional arguments it is demonstrated that any…

General Relativity and Quantum Cosmology · Physics 2013-06-14 D. Bennett , H. B. Nielsen

For a linear difference equation with the coefficients being computable sequences, we establish algorithmic undecidability of the problem of determining the dimension of the solution space including the case when some additional prior…

Symbolic Computation · Computer Science 2024-10-08 Sergei Abramov , Gleb Pogudin

Extra dimensions can be utilized to simplify problems in classical mechanics, offering new insights. Here we show a simple example of how the motion of a test particle under the influence of an inverse-quadratic potential in 1D is…

Classical Physics · Physics 2022-02-24 Trung Phan , Anh Doan

The addition of a topologically massive term to an admittedly non-unitary three-dimensional massive model, be it an electromagnetic system or a gravitational one, does not cure its non-unitarity. What about the enlargement of avowedly…

High Energy Physics - Theory · Physics 2009-11-11 Antonio Accioly , Marco Dias

In a metric space $M=(X,d)$, we say that $v$ is between $u$ and $w$ if $d(u,w)=d(u,v)+d(v,w)$. Taking all triples $\{u,v,w\}$ such that $v$ is between $u$ and $w$, one can associate a 3-uniform hypergraph with each finite metric space $M$.…

Combinatorics · Mathematics 2022-09-08 Vašek Chvátal , Ida Kantor

It has been shown that the extension of the elasticity theory in more than three dimensions allows a description of space-time as a properly stressed medium, even recovering the Minkowski metric in the case of uniaxial stress. The…

General Relativity and Quantum Cosmology · Physics 2008-02-03 A. Tartaglia

In three spacetime dimensions, general relativity drastically simplifies, becoming a ``topological'' theory with no propagating local degrees of freedom. Nevertheless, many of the difficult conceptual problems of quantizing gravity are…

General Relativity and Quantum Cosmology · Physics 2015-06-25 S. Carlip

We present the generalisation to (3+1) dimensions of a quantum deformation of the (2+1) (Anti)-de Sitter and Poincar\'e Lie algebras that is compatible with the conditions imposed by the Chern-Simons formulation of (2+1) gravity. Since such…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Angel Ballesteros , Francisco J. Herranz , Pedro Naranjo

We introduce two new formulations for the notion of "quantum metric on noncommutative space". For a compact noncommutative space associated to a unital C*-algebra, our quantum metrics are elements of the spatial tensor product of the…

Operator Algebras · Mathematics 2016-06-15 Maysam Maysami Sadr

In five dimensional cosmological models, the convention is to include the fifth dimension in a way similar to the other space dimensions. In this work we attempt to introduce the fifth dimension in a way that a time dimension would be…

General Relativity and Quantum Cosmology · Physics 2013-07-09 Gizem Sengor , Metin Arik

We construct two Hilbert spaces over the set of all metrics of arbitrary but fixed signature, defined on a manifold. Every state in one of the Hilbert spaces is built of an uncountable number of wave functions representing some elementary…

Mathematical Physics · Physics 2022-03-29 Andrzej Okolow

Recently, the first author together with Jens Marklof studied generalizations of the classical three distance theorem to higher dimensional toral rotations, giving upper bounds in all dimensions for the corresponding numbers of distances…

Number Theory · Mathematics 2020-12-08 Alan Haynes , Juan J. Ramirez

Maxwells classic equations with fields, potentials, positive and negative charges in 3+1 spacetime are derived solely from the symmetry that is required by the Geometric Algebra of a 3+3 spacetime. The observed direction of time is…

Mathematical Physics · Physics 2007-05-23 J. E. Carroll

Studying spacetimes with continuous symmetries by dimensional reduction to a lower dimensional spacetime is a well known technique in field theory and gravity. Recently, its use has been advocated in numerical relativity as an efficient…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Brannlund , S. Slobodov , K. Schleich , D. M. Witt

We explore the properties of physical theories in space-times with two time dimensions. We show that the common arguments used to rule such theories out do not apply if the dynamics associated with the additional time dimension is thermal…

High Energy Physics - Theory · Physics 2010-01-25 Jacob G. Foster , Berndt Müller

We derive a necessary and sufficient condition for Poincar\'e Lie superalgebras in any dimension and signature to be isomorphic. This reduces the classification problem, up to certain discrete operations, to classifying the orbits of the…

High Energy Physics - Theory · Physics 2020-10-28 Vicente Cortés , Louis Gall , Thomas Mohaupt

The macroscopic dimensions of space should not be input but rather output of a general model for physics. Here, dimensionality arises from a recently discovered mathematical bifurcation: positive versus indefinite manifold pairings. It is…

Quantum Physics · Physics 2010-12-02 Michael Freedman

In this article, we introduce the concept of lexicographic metric space and, after discussing some basic properties of these metric spaces, such as completeness, boundedness, compactness and separability, we obtain a formula for the metric…

Metric Geometry · Mathematics 2019-11-13 Juan Alberto Rodriguez-Velazquez

Several approaches to quantum gravity (including the model of superplastic vacuum; Diakonov tetrads emerging as the bilinear combinations of the fermionis fields; $BF$-theories of gravity; and effective acoustic metric) suggest that in…

General Relativity and Quantum Cosmology · Physics 2023-01-18 G. E. Volovik

We construct a metric space whose transfinite asymptotic dimension and complementary-finite asymptotic dimension are both omega+1, where omega is the smallest infinite ordinal number. Therefore, we prove that the omega conjecture is not…

Metric Geometry · Mathematics 2019-09-11 Yan Wu , Jingming Zhu