English
Related papers

Related papers: Non-commutative DKP equation and pair creation in …

200 papers

Analytic solutions for the evolution of cosmological linear density perturbations in the baryonic gas and collisionless dark matter are derived. The solutions are expressed in a closed form in terms of elementary functions, for arbitrary…

Astrophysics · Physics 2009-10-31 Adi Nusser

We propose a mathematical structure, based on a noncommutative geometry, which combines essential aspects of general relativity and quantum mechanics, and leads to correct "limiting cases" of both these theories. We quantize a groupoid…

General Relativity and Quantum Cosmology · Physics 2009-10-30 M. Heller , W. Sasin

We study the fermion pair production from a strong electric field in boost-invariant coordinates in (3+1) dimensions and exploit the cylindrical symmetry of the problem. This problem has been used previously as a toy model for populating…

High Energy Physics - Phenomenology · Physics 2014-11-18 Bogdan Mihaila , Fred Cooper , John F. Dawson

The oscillator representation is used for the non-perturbative description of vacuum particle creation in a strong time-dependent electric field in the framework of scalar QED. It is shown that the method can be more effective for the…

High Energy Physics - Theory · Physics 2009-11-10 V. N. Pervushin , V. V. Skokov , A. V. Reichel , S. A. Smolyansky , A. V. Prozorkevich

One presents a phase-space noncommutative extension of Quantum Cosmology in the context of a Kantowski-Sachs (KS) minisuperspace model. We obtain the Wheeler-DeWitt (WDW) equation for the noncommutative system through the ADM formalism and…

High Energy Physics - Theory · Physics 2009-07-24 C. Bastos , O. Bertolami , N. Dias , J. Prata

We propose a model for noncommutative quantum cosmology by means of a deformation of minisuperspace. For the Kantowski-Sachs metric we are able to find the exact wave function. We construct wave packets and show that new quantum states that…

High Energy Physics - Theory · Physics 2009-11-07 H. Garcia-Compean , O. Obregon , C. Ramirez

The aim of this paper is to compute transitions amplitudes in quantum cosmology, and in particular pair creation amplitudes and radiative transitions. To this end, we apply a double adiabatic development to the solutions of the…

General Relativity and Quantum Cosmology · Physics 2009-10-30 S. Massar , R. Parentani

In order to resolve the measurement problem of Quantum Mechanics, non-unitary time evolution has been derived from the unitarity of standard quantum formalism. New wave functions of free and non-free quantum systems follow from Schroedinger…

Quantum Physics · Physics 2007-05-23 Pradip Kumar Chatterjee

We explore the theoretical possibility that dark energy density is derived from the vacuum particle pairs together with the quantum fluctuation of space-time. By assuming the vacuum particle pairs fall into the horizon boundary of the…

General Relativity and Quantum Cosmology · Physics 2023-07-24 Long Huang , Xiao feng Yang , Xiang Liu

Time-space noncommutativity leads to quantisation of time and energy nonconservation when time is conjugate to a compact spatial direction like a circle. In this context energy is conserved only modulo some fixed unit. Such a possibility…

High Energy Physics - Theory · Physics 2010-10-27 A. P. Balachandran , A. G. Martins , P. Teotonio-Sobrinho

Similarly to the well-known phenomenon of particle / anti-particle pair production in strong electromagnetic fields (the Schwinger effect), the na\"ive matter field vacuum state can be excited by time-dependent, curved spacetime geometries.…

High Energy Physics - Theory · Physics 2026-02-11 Mohammed Alkhateeb , James P. Edwards , Yves Caudano

Quantum mechanics in its presently known formulation requires an external classical time for its description. A classical spacetime manifold and a classical spacetime metric are produced by classical matter fields. In the absence of such…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. P. Singh

There is renewed attention to whether we can observe the decoherence effect in neutrino oscillation due to the separation of wave packets with different masses in near-future experiments. As a contribution to this endeavor, we extend the…

High Energy Physics - Phenomenology · Physics 2023-10-18 Haruhi Mitani , Kin-ya Oda

The spontaneous production of electron-positron pairs from the vacuum--in a field configuration composed of a high-frequency electric mode of weak intensity and a strong constant electric field--is investigated. Asymptotic expressions for…

High Energy Physics - Phenomenology · Physics 2019-12-25 Selym Villalba-Chávez , Carsten Müller

The dynamics of a spin--1/2 neutral particle possessing electric and magnetic dipole moments interacting with external electric and magnetic fields in noncommutative coordinates is obtained. Noncommutativity of space is interposed in terms…

High Energy Physics - Theory · Physics 2009-08-03 Omer F. Dayi

Non-Markovian effects in quantum evolution appear when the system is strongly coupled to the environment and interacts with it for long periods of time. To include memory effects in the master equations, one usually incorporates time-local…

Quantum Physics · Physics 2020-11-24 Katarzyna Siudzińska , Dariusz Chruściński

We develop a general numerical method aimed at studying particle production from vacuum states in a variety of settings. As a first example we look at particle production in a simple cosmological model. We apply the same approach to the…

High Energy Physics - Phenomenology · Physics 2016-09-06 Nuno D. Antunes

Nondispersive wave packets in a fictitious time variable are calculated analytically for the field-free hydrogen atom. As is well known by means of the Kustaanheimo-Stiefel transformation the Coulomb problem can be converted into that of a…

Atomic Physics · Physics 2009-04-21 T. Fabčič , J. Main , G. Wunner

We present a relativistic formulation of noncommutative mechanics were the object of noncommutativity $\theta^{\mu\nu}$ is considered as an independent quantity. Its canonical conjugate momentum is also introduced, what permits to obtain an…

High Energy Physics - Theory · Physics 2010-05-25 R. Amorim , E. M. C. Abreu , W. G. Ramirez

We consider the Standard Model on a non-commutative space and expand the action in the non-commutativity parameter theta. No new particles are introduced, the structure group is SU(3) x SU(2) x U(1). We derive the leading order action. At…

High Energy Physics - Phenomenology · Physics 2011-01-05 X. Calmet , B. Jurco , P. Schupp , J. Wess , M. Wohlgenannt