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Related papers: Lessons from the LQG String

200 papers

The volume operator plays a central role in both the kinematics and dynamics of canonical approaches to quantum gravity which are based on algebras of generalized Wilson loops. We introduce a method for simplifying its spectral analysis,…

General Relativity and Quantum Cosmology · Physics 2009-10-30 R. Loll

Loop quantum gravity (LQG) is a quantization program for gravity based on the principles of QFT and general covariance of general relativity. Quantum states of LQG describe gravitational excitations based on graphs embedded in a spatial…

General Relativity and Quantum Cosmology · Physics 2024-10-18 Hanno Sahlmann , Waleed Sherif

A generalization of canonical quantization which maps a dynamical operator to a dynamical superoperator is suggested. Weyl quantization of dynamical operator, which cannot be represented as Poisson bracket with some function, is considered.…

Quantum Physics · Physics 2009-11-10 Vasily E. Tarasov

We re-examine physical state representations in the covariant quantization of bosonic string. We especially consider one parameter family of gauge fixing conditions for the residual gauge symmetry due to null states (or BRST exact states),…

High Energy Physics - Theory · Physics 2009-11-11 Masako Asano , Mitsuhiro Kato , Makoto Natsuume

We introduce a special class of truncated Weyl-Heisenberg algebra and discuss the corresponding Hilbertian and analytical representations. Subsequently, we study the effect of a quantum network of beam splitting on coherent states of this…

Quantum Physics · Physics 2012-10-30 M. Daoud , A. Jellal , E. B. Choubabi , E. H. El Kinani

The quantum nature of the state of a bosonic quantum field manifests itself in its entanglement, coherence, or optical nonclassicality which are each known to be resources for quantum computing or metrology. We provide quantitative and…

Quantum Physics · Physics 2020-09-25 Anaelle Hertz , Nicolas J. Cerf , Stephan De Bièvre

It is known that the anti-Wick (or standard coherent state) quantization of the complex plane produces both canonical commutation rule and quantum spectrum of the harmonic oscillator (up to the addition of a constant). In the present work,…

Quantum Physics · Physics 2010-01-20 Katarzyna Gorska , Jean Pierre Gazeau , Nicolae Cotfas

In the covariant-gauge two-dimensional quantum gravity, various derivations of the critical dimension D=26 of the bosonic string are critically reviewed, and their interrelations are clarified. It is shown that the string theory is not…

High Energy Physics - Theory · Physics 2009-10-30 Mitsuo Abe , Noboru Nakanishi

Free scalar field theory on 2 dimensional flat spacetime, cast in diffeomorphism invariant guise by treating the inertial coordinates of the spacetime as dynamical variables, is quantized using LQG type `polymer' representations for the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alok Laddha , Madhavan Varadarajan

In this paper a generalization of Weyl quantization which maps a dynamical operator in a function space to a dynamical superoperator in an operator space is suggested. Quantization of dynamical operator, which cannot be represented as…

Quantum Physics · Physics 2007-05-23 Vasily E. Tarasov

Standard quantum mechanics is viewed as a limit of a cut system with artificially restricted dimension of a Hilbert space. Exact spectrum of cut momentum and coordinate operators is derived and the limiting transition to the infinite…

High Energy Physics - Theory · Physics 2007-05-23 M. Trzetrzelewski , J. Wosiek

Based on Feynman's lifetime efforts on quantum mechanics and relativity, it is concluded that the basic difference between field theory and string theory is that field theory is based on running waves while string theory should deal with…

High Energy Physics - Phenomenology · Physics 2007-05-23 Y. S. Kim , Marilyn E. Noz

This series of lectures gives a simple and self-contained introduction to the non-perturbative and background independent loop approach of canonical quantum gravity. The Hilbert space of kinematical quantum states is constructed and a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcus Gaul , Carlo Rovelli

Motivated by a recent proposal (by Koslowski-Sahlmann) of a kinematical representation in Loop Quantum Gravity (LQG) with a nondegenerate vacuum metric, we construct a polymer quantization of the parametrised massless scalar field theory on…

General Relativity and Quantum Cosmology · Physics 2013-09-12 Sandipan Sengupta

The notion of f-oscillators generalizing q-oscillators is introduced. For classical and quantum cases, an interpretation of the f-oscillator is provided as corresponding to a special nonlinearity of vibration for which the frequency of…

Quantum Physics · Physics 2016-09-08 V. I. Man'ko , G. Marmo , E. C. G. Sudarshan , F. Zaccaria

We investigate the quantization of the bosonic string model which has a local U(1)_V * U(1)_A gauge invariance as well as the general coordinate and Weyl invariance on the world-sheet. The model is quantized by Lagrangian and Hamiltonian…

High Energy Physics - Theory · Physics 2009-11-10 Takuya Tsukioka , Yoshiyuki Watabiki

Loop Quantum Gravity (LQG) is a promising approach to quantum gravity, in particular because it is based on a rigorous quantization of the kinematics of gravity. A difficult and still open problem in the LQG program is the construction of…

General Relativity and Quantum Cosmology · Physics 2013-03-01 Tim Koslowski

We present a simple physical representation for states of the two-dimensional string theory. In order to incorporate a fundamental cutoff of the order 1/g we use a picture consisting of q-oscillators at the first-quantized level. In this…

High Energy Physics - Theory · Physics 2007-05-23 Antal Jevicki , Andre van Tonder

In this paper we view the sigma-model couplings of appropriate vertex operators describing the interaction of string matter with a certain type of string solitons (0-branes) as the quantum phase space of a point particle. The sigma-model is…

High Energy Physics - Theory · Physics 2016-09-06 F. Lizzi , N. E. Mavromatos

We present in the article the formulation of a version of Lorentz covariant quantum mechanics based on a group theoretical construction from a Heisenberg-Weyl symmetry with position and momentum operators transforming as Minkowski…

Quantum Physics · Physics 2021-12-07 Suzana Bedić , Otto C. W. Kong , Hock King Ting