Emergent Time and Time Travel in Quantum Physics

• URL: http://arxiv.org/abs/2312.05202v2
• Date: Tue, 27 Feb 2024 14:18:23 GMT
• Title: Emergent Time and Time Travel in Quantum Physics
• Authors: Ana Alonso-Serrano (Humboldt-Universit\"at zu Berlin and Max-Planck-Institut f\"ur Gravitationsphysik, Potsdam), Sebastian Schuster (Charles University Prague), Matt Visser (Victoria University of Wellington)
• Abstract summary: We will study toy models implementing the Hamiltonian constraint in quantum theory. An aim towards understanding what an emergent notion of time can tell us about the (im)posibilitys of time travel.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: 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 well-established fields of physics. Sometimes, the interpretation is that only a full theory of quantum gravity will be able to settle these logical contradictions. Even then, it remains unclear if the multitude of problems could be overcome. Yet as definitive as this seems to the notion of time travel in physics, such a recourse to quantum gravity comes with its own, long-standing challenge to most of these counter-arguments to time travel: These arguments rely on time, while quantum gravity is (in)famously stuck with and dealing with the problem of time. One attempt to answer this problem within the canonical framework resulted in the Page-Wootters formalism, and its recent gauge-theoretic re-interpretation - as an emergent notion of time. Herein, we will begin a programme to study toy models implementing the Hamiltonian constraint in quantum theory, with an aim towards understanding what an emergent notion of time can tell us about the (im)possibility of time travel.

Related papers

• Table-top nanodiamond interferometer enabling quantum gravity tests [34.82692226532414]
  We present a feasibility study for a table-top nanodiamond-based interferometer. By relying on quantum superpositions of steady massive objects our interferometer may allow exploiting just small-range electromagnetic fields.
  arXiv  Detail & Related papers  (2024-05-31T17:20:59Z)
• Relaxation of first-class constraints and the quantization of gauge theories: from "matter without matter" to the reappearance of time in quantum gravity [72.27323884094953]
  We make a conceptual overview of an approach to the initial-value problem in canonical gauge theories. We stress how the first-class phase-space constraints may be relaxed if we interpret them as fixing the values of new degrees of freedom.
  arXiv  Detail & Related papers  (2024-02-19T19:00:02Z)
• Unitarity and quantum resolution of gravitational singularities [0.0]
  We show that unitarity for a clock that encounters a classical singularity at finite time implies quantum resolution, but for a clock that encounters future infinity at finite time leads to a quantum recollapse.
  arXiv  Detail & Related papers  (2022-05-30T19:11:33Z)
• The solution to the problem of time in quantum gravity also solves the time of arrival problem in quantum mechanics [0.0]
  We introduce a solution to the problem of time in quantum gravity which consists in formulating the quantum theory in terms of real clocks. We show here that this construction provides a natural solution to the time of arrival problem in quantum mechanics and leads to a well defined time-energy uncertainty relation for the clocks.
  arXiv  Detail & Related papers  (2022-04-18T15:30:24Z)
• Time and Quantum Clocks: a review of recent developments [0.0]
  We present the problem of time in quantum physics, including a short history of the problem and the known objections about considering time a quantum observable. The lack of a consistent theory of time is currently hindering the formulation of a full-fledged theory of quantum gravity.
  arXiv  Detail & Related papers  (2022-03-23T17:25:48Z)
• A Quantum Informational Approach to the Problem of Time [0.0]
  We argue using quantum information theory that the Hamiltonian constraint in quantum gravity cannot probe change. If the time-reparametization symmetry is spontaneously broken due to the formation of quantum cosmological time crystals, these problems can be resolved.
  arXiv  Detail & Related papers  (2021-12-02T01:30:53Z)
• Time and Evolution in Quantum and Classical Cosmology [68.8204255655161]
  We show that it is neither necessary nor sufficient for the Poisson bracket between the time variable and the super-Hamiltonian to be equal to unity in all of the phase space. We also discuss the question of switching between different internal times as well as the Montevideo interpretation of quantum theory.
  arXiv  Detail & Related papers  (2021-07-02T09:17:55Z)
• Measuring time with stationary quantum clocks [0.0]
  We show that a quantum clock can measure the passage of time even while being switched off. This supports the so-called substantival theory of time.
  arXiv  Detail & Related papers  (2021-06-14T18:08:41Z)
• There is only one time [110.83289076967895]
  We draw a picture of physical systems that allows us to recognize what is this thing called "time" We derive the Schr"odinger equation in the first case, and the Hamilton equations of motion in the second one.
  arXiv  Detail & Related papers  (2020-06-22T09:54:46Z)
• Quantum time dilation: A new test of relativistic quantum theory [91.3755431537592]
  A novel quantum time dilation effect is shown to arise when a clock moves in a quantum superposition of two relativistic velocities. This effect is argued to be measurable using existing atomic interferometry techniques, potentially offering a new test of relativistic quantum theory.
  arXiv  Detail & Related papers  (2020-04-22T19:26:53Z)
• Projection evolution and quantum spacetime [68.8204255655161]
  We discuss the problem of time in quantum mechanics. An idea of construction of a quantum spacetime as a special set of the allowed states is presented. An example of a structureless quantum Minkowski-like spacetime is also considered.
  arXiv  Detail & Related papers  (2019-10-24T14:54:11Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.