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Related papers: Time paradox in Quantum Gravity

200 papers

We discuss the hints for the disappearance of continuum space and time at microscopic scale. These include arguments for a discrete nature of them or for a fundamental non-locality, in a quantum theory of gravity. We discuss how these ideas…

History and Philosophy of Physics · Physics 2013-02-13 Daniele Oriti

We discuss how the classical notions of time and causal structure may emerge together with quantum-mechanical probabilities from a universal quantum state. For this, the process of decoherence between semiclassical branches is important.…

General Relativity and Quantum Cosmology · Physics 2025-06-24 Leonardo Chataignier , Claus Kiefer , Mritunjay Tyagi

Entertaining the possibility of time travel will invariably challenge dearly held concepts of fundamental physics. It becomes relatively easy to construct multiple logical contradictions using differing starting points from various…

General Relativity and Quantum Cosmology · Physics 2024-02-28 Ana Alonso-Serrano , Sebastian Schuster , Matt Visser

The failure of conventional quantum theory to recognize time as an observable and to admit time operators is addressed. Instead of focusing on the existence of a time operator for a given Hamiltonian, we emphasize the role of the…

Quantum Physics · Physics 2013-05-24 Curt A. Moyer

Our fundamental theories, i.e., the quantum theory and general relativity, are invariant under time reversal. Only when we treat system from the point of view of thermodynamics, i.e., averaging between many subsystem components, an arrow of…

History and Philosophy of Physics · Physics 2024-10-01 Francesca Vidotto

We consider a toy model of the interaction of a qubit with an exotic space-time containing a time-like curve. Consistency seems to require that the global evolution of the qubit be non-unitary. Given that quantum mechanics is globally…

Quantum Physics · Physics 2008-11-26 T. C. Ralph

It is postulated there is not a precise static instant in time underlying a dynamical physical process at which the relative position of a body in relative motion or a specific physical magnitude would theoretically be precisely determined.…

General Physics · Physics 2007-05-23 Peter Lynds

We point out a fundamental problem that hinders the quantization of general relativity: quantum mechanics is formulated in terms of systems, typically limited in space but infinitely extended in time, while general relativity is formulated…

Quantum Physics · Physics 2020-01-08 Lorenzo Maccone

Quantum matter in quantum space-time is discussed using general properties of energy-conservation laws. As a rather radical conclusion, it is found that standard methods of differential geometry and quantum field theory on curved space-time…

General Relativity and Quantum Cosmology · Physics 2013-11-13 Martin Bojowald , Golam Mortuza Hossain , Mikhail Kagan , Casey Tomlin

Understanding the emergence of a tangible 4-dimensional space-time from a quantum theory of gravity promises to be a tremendously difficult task. This article makes the case that this task may not have to be carried. Space-time as we know…

History and Philosophy of Physics · Physics 2018-11-14 Antoine Tilloy

The appearance of Hamiltonian constraint in the canonical formalism for general relativity reflects the lack of a fixed external time. The dynamics of general relativistic systems can be expressed with respect to an arbitrarily chosen…

General Relativity and Quantum Cosmology · Physics 2017-09-21 Przemyslaw Malkiewicz

A new interpretation of quantum mechanics, similar to the Copenhagen interpretation, is developed from time-symmetry arguments and commonly held principles concerning time and causality. These principles, which are grounded in ideas outside…

Quantum Physics · Physics 2007-05-23 William R. Wharton

We have performed an experimental test under the conditions of which quantum mechanics predicts a spatially-discontinuous single-particle transport. The transport is beyond the relativistic paradigm of movement in Cartesian space and…

General Physics · Physics 2013-06-14 S. A. Emelyanov

Spacetime manifolds that are not time orientable play a key role in a gravitational explanation of quantum theory. Such manifolds allow topology change, but also have fascinating additional properties such as net charge from source-free…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mark J Hadley

This thesis contains an analysis of the problem of time in quantum cosmology and its application to a cosmological minisuperspace model. In the first part, we introduce the problem of time and the theoretical foundations. In the second…

General Relativity and Quantum Cosmology · Physics 2022-11-18 Lucía Menéndez-Pidal

A quantum mechanical theory is proposed which abandons an external parameter ``time'' in favor of a self-adjoint operator on a Hilbert space whose elements represent measurement events rather than system states. The standard quantum…

Quantum Physics · Physics 2009-09-29 Kim Bostroem

All differences between the role of space and time in nature are explained by proposing the principles in which none of the spacetime coordinates has an {\it a priori} special role. Spacetime is treated as a non-dynamical manifold, with a…

General Relativity and Quantum Cosmology · Physics 2023-04-25 Hrvoje Nikolic

Minkowski space serves as a framework for the theoretical constructions that deal with manifestations of relativistic effects in physical phenomena. But neither Minkowski himself nor the subsequent developers of the relativity theory have…

General Physics · Physics 2019-01-17 Serge Wagner

Starting from a new understanding of the vacuum energy problem based on the combination of the phase space regularization and the holographic bound, we argue that quantum gravity should be understood as gravitized quantum theory, that is,…

High Energy Physics - Theory · Physics 2024-07-10 Tristan Hübsch , Djordje Minic

Theories of quantum gravity generically presuppose or predict that the reality underlying relativistic spacetimes they are describing is significantly non-spatiotemporal. On pain of empirical incoherence, approaches to quantum gravity must…

History and Philosophy of Physics · Physics 2018-05-03 Vincent Lam , Christian Wuthrich