Quick search Find article
Quick search
Find article

The flat FRW model in LQC: self-adjointness

Wojciech Kamiński and Jerzy Lewandowski

Show affiliations


The flat Friedman–Robertson–Walker (FRW) model coupled to the massless scalar field according to the improved, background scale-independent version of Ashtekar, Pawłowski and Singh [1] is considered. The core of the theory is addressed directly: the APS construction of the quantum Hamiltonian is analyzed under the assumption that the cosmological constant Λ ≤ 0. We prove the essential self-adjointness of the operator whose square-root defines in [1] the quantum Hamiltonian operator and therefore provide the explicit definition. If Λ < 0, then the spectrum is discrete. In the Λ = 0 case, the essential and absolutely continuous spectra of the operator are derived. The latter operator is related in the unitary way to the absolutely continuous part of the quantum mechanics operator a\big({-}\frac{\partial^2}{\partial y^2} - \frac{b}{{\rm cosh}^2\hat{y}}\big) (a, b > 0 being some constants) plus a trace class operator.


PACS

98.80.Cq Particle-theory and field-theory models of the early Universe (including cosmic pancakes, cosmic strings, chaotic phenomena, inflationary universe, etc.)

98.80.Es Observational cosmology (including Hubble constant, distance scale, cosmological constant, early Universe, etc)

95.30.Sf Relativity and gravitation

04.60.Pp Loop quantum gravity, quantum geometry, spin foams

98.80.Qc Quantum cosmology

MSC

83C45 Quantization of the gravitational field

83F05 Cosmology

47L30 Abstract operator algebras on Hilbert spaces

85A40 Cosmology (For relativistic cosmology, see 83F05)

81R15 Operator algebra methods (See also 46Lxx, 81T05)

Subjects

Gravitation and cosmology

Astrophysics and astroparticles

Dates

Issue 3 (7 February 2008)

Received 26 August 2007, in final form 5 December 2007

Published 14 January 2008



  1. The flat FRW model in LQC: self-adjointness

    Wojciech Kamiński and Jerzy Lewandowski 2008 Class. Quantum Grav. 25 035001

  2. An open FRW model in loop quantum cosmology

    Łukasz Szulc 2007 Class. Quantum Grav. 24 6191

  3. Renewal processes and fluctuation analysis of molecular motor stepping

    Jaime E Santos et al 2005 Phys. Biol. 2 207

  4. A classification of hidden-variable properties

    Adam Brandenburger and Noson Yanofsky 2008 J. Phys. A: Math. Theor. 41 425302

  5. The causal boundary of the trousers space

    S G Harris and T Dray 1990 Class. Quantum Grav. 7 149

  6. Statistics and geometry of cosmic voids

    José Gaite JCAP11(2009)004

  7. The cosmological constant problem and quintessence

    Varun Sahni 2002 Class. Quantum Grav. 19 3435

  8. Semiclassical states in quantum cosmology: Bianchi I coherent states

    Brett Bolen et al 2004 Class. Quantum Grav. 21 4087

  9. The information paradox: a pedagogical introduction

    Samir D Mathur 2009 Class. Quantum Grav. 26 224001

  10. On the motion of spinning test particles in plane gravitational waves

    M Mohseni et al 2001 Class. Quantum Grav. 18 3007

View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.