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We present an in-depth investigation of the ${\rm SL}(2,\mathbb{R})$ momentum space describing point particles coupled to Einstein gravity in three space-time dimensions. We introduce different sets of coordinates on the group manifold and…

General Relativity and Quantum Cosmology · Physics 2014-07-25 Michele Arzano , Danilo Latini , Matteo Lotito

While real Hamiltonian mechanics and Hermitian quantum mechanics can both be cast in the framework of complex canonical equations, their complex generalisations have hitherto been remained tangential. In this paper quaternionic and…

Mathematical Physics · Physics 2015-03-17 Dorje C Brody , Eva-Maria Graefe

We provide a novel model of gravity by using adjoint frame fields in four dimensions. It has a natural interpretation as a gravitational theory of a complex metric field, which describes interactions between two real metrics. The classical…

High Energy Physics - Theory · Physics 2015-12-14 Zhi-Qiang Guo , Ivan Schmidt

Analytical formulae are derived for the zero-point vibrational energy and anharmonicity corrections of the cohesive energy and the mode Gr\"{u}neisen parameter within the Einstein model for the cubic lattices (sc, bcc and fcc) and for the…

Materials Science · Physics 2021-06-09 Peter Schwerdtfeger , Antony Burrows , Odile R. Smits

We study Bohr-Sommerfeld states in the context of the irreducible representations of SU(2). These states offer a precise bridge between the classical and quantum descriptions of angular momentum. We show that they recover the usual basis of…

Mathematical Physics · Physics 2023-07-03 Bruce Bartlett , Nzaganya Nzaganya

This article deals with the study of electromagnetic waves equations and the Lorentz condition, as emergent properties of Maxwell's system in the context of systems theory. To do this, the wave equations and the Helmholtz equation are first…

Classical Physics · Physics 2020-10-28 Yudier Peña Pérez , Juan Bory Reyes

We perform a canonical quantization of gravity in a second-order formulation, taking as configuration variables those describing a 4-bein, not adapted to the space-time splitting. We outline how, neither if we fix the Lorentz frame before…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francesco Cianfrani , Giovanni Montani

It is known that local, Lorentz invariant, unitary theories involving particles with spin 1 demand that the matter sector they couple to are organized by internal physical symmetries and the associated charge conservation, while spin 3/2…

High Energy Physics - Theory · Physics 2020-08-12 Mark P. Hertzberg , Jacob A. Litterer , McCullen Sandora

In this work, we propose using real quaternions for the definition of the time interval resulting in an alternative formulation of the relativistic space-time. We proceed with the quaternion definition of the particle mass that we derive…

General Physics · Physics 2017-09-07 Viktor Ariel

We show that the geometry of $4n$-dimensional quaternionic K\"ahler spaces with a locally free $\mathbb{R}^{n+1}$-action admits a Gibbons-Hawking-like description based on the Galicki-Lawson notion of quaternionic K\"ahler moment map. This…

Differential Geometry · Mathematics 2019-07-16 Radu A. Ionas

Twisted torus links are given by twisting a subset of strands on a closed braid representative of a torus link. T--links are a natural generalization, given by repeated positive twisting. We establish a one-to-one correspondence between…

Geometric Topology · Mathematics 2014-02-26 Joan Birman , Ilya Kofman

We develop the bivector formalism in higher dimensional Lorentzian spacetimes. We define the Weyl bivector operator in a manner consistent with its boost-weight decomposition. We then algebraically classify the Weyl tensor, which gives rise…

General Relativity and Quantum Cosmology · Physics 2010-01-06 A Coley , S Hervik

We present the construction of a new state sum model for $4d$ Lorentzian quantum gravity based on the description of quantum simplicial geometry in terms of edge vectors. Quantum states and amplitudes for simplicial geometry are built from…

General Relativity and Quantum Cosmology · Physics 2025-01-20 Roukaya Dekhil , Matteo Laudonio , Daniele Oriti

The canonical decomposition of a Lorentz algebra element into a sum of orthogonal simple (decomposable) Lorentz bivectors is discussed, as well as the decomposition of a proper orthochronous Lorentz transformation into a product of…

General Relativity and Quantum Cosmology · Physics 2012-11-27 Jason Hanson

The Dirac belt trick is often employed in physics classrooms to show that a $2\pi$ rotation is not topologically equivalent to the absence of rotation whereas a $4\pi$ rotation is, mirroring a key property of quaternions and their…

Popular Physics · Physics 2015-05-14 Mark Staley

The attitude space has been parameterized in various ways for practical purposes. Different representations gain preferences over others based on their intuitive understanding, ease of implementation, formulaic simplicity, and physical as…

Systems and Control · Computer Science 2017-08-30 Hardik Parwana , Mangal Kothari

It is shown that the quaternionic Hilbert space formulation of quantum mechanics allows a quantization, based on a generalized system of imprimitivity, that leads to a description of the motion of a quantum particle in the field of a…

Quantum Physics · Physics 2022-04-05 G. G. Emch , A Jadczyk

We set up an Einstein-Gauss-Bonnet theory in four dimensions, based on the recent formulation of pure gravity with extra dimensions of vanishing metrical length [1]. In absence of torsion, the effective field equations depend only on the…

General Relativity and Quantum Cosmology · Physics 2022-02-11 Sandipan Sengupta

In the description of general covariance, the vierbein and the Lorentz connection can be treated as independent fundamental fields. With the usual gauge Lagrangian, the Lorentz connection is characterized by an asymptotically free running…

High Energy Physics - Theory · Physics 2017-08-16 John F. Donoghue

The issues of quintessence and cosmic acceleration can be discussed in the framework of higher order theories of gravity. We can define effective pressure and energy density directly connected to the Ricci scalar of curvature of a generic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Salvatore Capozziello