Loop quantum cosmology
Encyclopedia
Loop quantum cosmology is a finite, symmetry-reduced model of loop quantum gravity
that predicts a quantum bridge between contracting and expanding cosmological branches. Study of LQC has led to many successes, including the emergence of a possible mechanism for cosmic inflation
, resolution of gravitational singularities as well as development of effective, semi-classical Hamiltonians
. This subfield was originally started in 1999 by Martin Bojowald
and further developed in particular by Abhay Ashtekar
and Jerzy Lewandowski. At present LQC represents a very active field, with about three hundred papers in the literature.
Loop quantum gravity
Loop quantum gravity , also known as loop gravity and quantum geometry, is a proposed quantum theory of spacetime which attempts to reconcile the theories of quantum mechanics and general relativity...
that predicts a quantum bridge between contracting and expanding cosmological branches. Study of LQC has led to many successes, including the emergence of a possible mechanism for cosmic inflation
Cosmic inflation
In physical cosmology, cosmic inflation, cosmological inflation or just inflation is the theorized extremely rapid exponential expansion of the early universe by a factor of at least 1078 in volume, driven by a negative-pressure vacuum energy density. The inflationary epoch comprises the first part...
, resolution of gravitational singularities as well as development of effective, semi-classical Hamiltonians
Hamiltonian (quantum mechanics)
In quantum mechanics, the Hamiltonian H, also Ȟ or Ĥ, is the operator corresponding to the total energy of the system. Its spectrum is the set of possible outcomes when one measures the total energy of a system...
. This subfield was originally started in 1999 by Martin Bojowald
Martin Bojowald
Martin Bojowald is a German physicist who now works on the faculty of the Penn State Physics Department, where he is a member of the Institute for Gravitation and the Cosmos. Prior to joining Penn State he spent several years at the Max-Planck Institute for Gravitational Physics in Potsdam, Germany...
and further developed in particular by Abhay Ashtekar
Abhay Ashtekar
Abhay Vasant Ashtekar is an Indian theoretical physicist. He is the Eberly Professor of Physics and the Director of the Institute for Gravitational Physics and Geometry at Pennsylvania State University. As the creator of Ashtekar variables, he is one of the founders of loop quantum gravity and its...
and Jerzy Lewandowski. At present LQC represents a very active field, with about three hundred papers in the literature.