English
Related papers

Related papers: Cosmic time and the initial state of the universe

200 papers

The Hamiltonian of Intrinsic Time Gravity is elucidated. The theory describes Schrodinger evolution of our universe with respect to the fractional change of the total spatial volume. Gravitational interactions are introduced by extending…

General Relativity and Quantum Cosmology · Physics 2021-01-12 Eyo Eyo Ita , Chopin Soo , Hoi-Lai Yu

Quantum geometrodynamics with intrinsic time development is presented. Paradigm shift from full space-time covariance to spatial diffeomorphism invariance yields a non-vanishing Hamiltonian, a resolution of the `problem of time', and…

General Relativity and Quantum Cosmology · Physics 2016-12-16 Chopin Soo

We investigate the effect on the Hamiltonian structure of general relativity of choosing an intrinsic time to fix the time slicing. 3-covariance with momentum constraint is maintained, but the Hamiltonian constraint is replaced by a…

General Relativity and Quantum Cosmology · Physics 2013-04-30 Niall Ó Murchadha , Chopin Soo , Hoi-Lai Yu

Quantum Geometrodynamics with intrinsic time development and momentric variables is presented. An underlying SU(3) group structure at each spatial point regulates the theory. The intrinsic time behavior of the theory is analyzed, together…

General Relativity and Quantum Cosmology · Physics 2015-08-12 Eyo Eyo Ita , Chopin Soo , Hoi-Lai Yu

In an ever-expanding spatially closed universe, the fractional change of the volume is the preeminent intrinsic time interval to describe evolution in General Relativity. The expansion of the universe serves as a subsidiary condition which…

General Relativity and Quantum Cosmology · Physics 2018-06-14 Eyo Eyo Ita , Chopin Soo , Hoi-Lai Yu

We propose that cosmological time is {\it effectively} the conjugate of the constants of nature. Different definitions of time arise, with the most relevant related to the constant controlling the dynamics in each epoch. The Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2021-06-30 Joao Magueijo

The framework of a theory of gravity from the quantum to the classical regime is presented. The paradigm shift from full spacetime covariance to spatial diffeomorphism invariance, together with clean decomposition of the canonical…

General Relativity and Quantum Cosmology · Physics 2019-12-06 Chopin Soo , Hoi-Lai Yu

We study longstanding problem of cosmological clock in the context of Brans-Dicke theory of gravitation. We present the Hamiltonian formulation of the theory for a class of spatially homogenous cosmological models. Then, we show that…

General Relativity and Quantum Cosmology · Physics 2011-06-09 Hossein Farajollahi , Mehrdad Farhoudi , Hossein Shojaie

We revisit pure quantum cosmology in three dimensions. The Wheeler-DeWitt equation can be solved perturbatively and the dynamics reduces to a particle on moduli space. Its time evolution is equivalent to the $T\overline{T}$ deformation.…

High Energy Physics - Theory · Physics 2024-05-21 Victor Godet

[Shortened abstract:] In this thesis we investigate a solution to the `problem of time' in canonical quantum gravity by splitting spacetime into surfaces of constant mean curvature parameterised by York time. We argue that there are reasons…

General Relativity and Quantum Cosmology · Physics 2016-09-14 Philipp Roser

We examine in greater detail the proposal that time is the conjugate of the constants of nature. Fundamentally distinct times are associated with different constants, a situation often found in "relational time" settings. We show in detail…

General Relativity and Quantum Cosmology · Physics 2022-10-14 Joao Magueijo

The quantum description of time evolution in non-linear gravitational systems such as cosmological space-times is not well understood. We show, in the simplified setting of mini-superspace, that time evolution of this system can be obtained…

General Relativity and Quantum Cosmology · Physics 2023-05-02 Anne-Katherine Burns , David E. Kaplan , Tom Melia , Surjeet Rajendran

Intrinsic time quantum geometrodynamics resolved `the problem of time' and bridged the deep divide between quantum mechanics and canonical quantum gravity with a Schrodinger equation which describes evolution in intrinsic time variable. In…

General Relativity and Quantum Cosmology · Physics 2016-01-18 Huei-Chen Lin , Chopin Soo

A model of a stationary universe is proposed. In this framework, time is defined as a local and quantum-mechanical notion in the sense that it is defined for each local and quantum-mechanical system consisting of finite number of particles.…

Astrophysics · Physics 2010-11-19 Hitoshi Kitada

We discuss the problem of time in spherically symmetric pure Einstein gravity with the cosmological term by using an exact solution to the Wheeler-DeWitt equation. A positive definite inner product is defined, based on the momentum…

High Energy Physics - Theory · Physics 2010-11-19 Takayuki Hori

Hamilton-Jacobi theory provides a natural starting point for a covariant description of the gravitational field. Using a spatial gradient expansion, one may solve for the phase of the wavefunction by using a line-integral in superspace.…

Astrophysics · Physics 2007-05-23 D. S. Salopek

Space-time quantum contributions to the classical Einstein equations of General Relativity are determined. The theoretical background is provided by the non-perturbative theory of manifestly-covariant quantum gravity and the…

General Relativity and Quantum Cosmology · Physics 2018-07-18 Claudio Cremaschini , Massimo Tessarotto

One method to overcome the notorious problem of time in the quantisation of gravity is the identification of a physically preferred time parameter, a promising candidate being so-called `York time'. The dynamical equations for matter and…

General Relativity and Quantum Cosmology · Physics 2015-11-12 Philipp Roser

The covariant canonical transformation theory applied to the relativistic Hamiltonian theory of classical matter fields in dynamical space-time yields a novel (first order) gauge field theory of gravitation. The emerging field equations…

General Relativity and Quantum Cosmology · Physics 2023-11-29 David Vasak , Johannes Kirsch , Dirk Kehm , Juergen Struckmeier

A new dynamical paradigm merging quantum dynamics with cosmology is discussed. Time evolution involves a genuine passage of time, which distinguishes the formalism from those where dynamics in space is equivalent to statics in space-time.…

General Physics · Physics 2024-02-01 Marek Czachor
‹ Prev 1 2 3 10 Next ›