Quantum mechanics near closed timelike lines.

  title={Quantum mechanics near closed timelike lines.},
  journal={Physical review. D, Particles and fields},
  volume={44 10},
  • Deutsch
  • Published 15 November 1991
  • Physics
  • Physical review. D, Particles and fields
The methods of the quantum theory of computation are used to analyze the physics of closed timelike lines. This is dominated, even at the macroscopic level, by quantum mechanics. In classical physics the existence of such lines in a spacetime imposes "paradoxical" constraints on the state of matter in their past and also provides means for knowledge to be created in ways that conflict with the principles of the philosophy of science. In quantum mechanics the first of these pathologies does not… 

Figures from this paper

The breakdown of quantum mechanics in the presence of time machinest

General Relativity allows for the existence of closed timelike curves. Various attempts have been made to exploit this possibility and build a “time machine,” that is a spacetime that has closed

Causality violation and nonlinear quantum mechanics

It is currently unknown whether the laws of physics permit time travel into the past. While general relativity indicates the theoretical possibility of causality violation, it is now widely accepted

Matters of time directionality in classical and quantum physics

This report offers a modern perspective on the question of time directionality as it arises in a classical and quantum mechanical context, based on key developments in the field of gravitational

Closed timelike curves and the second law of thermodynamics

One out of many emerging implications from solutions of Einstein's general relativity equations are closed timelike curves (CTCs), which are trajectories through spacetime that loop back on

Quantum causal histories in the light of quantum information

We use techniques of quantum information theory to analyze the quantum causal histories approach to quantum gravity. While it is consistent to introduce closed timelike curves (CTCs), they cannot

Gravity, Quantum Fields and Quantum Information: Problems with Classical Channel and Stochastic Theories

In recent years an increasing number of papers have attempted to mimic or supplant quantum field theory in discussions of issues related to gravity by the tools and through the perspective of quantum

Do the laws of physics forbid the operation of time machines?

The verdict on the question of whether it is possible to operate a time machine by manipulating matter and energy so as to manufacture closed timelike curves is that no result of sufficient generality to underwrite a confident “yes” has been proven.

Quantum fields on closed timelike curves

Recently, there has been much interest in the evolution of quantum particles on closed timelike curves (CTCs). However, such models typically assume pointlike particles with only two degrees of

Quantum Physics, Fields and Closed Timelike Curves: The D-CTC Condition in Quantum Field Theory

The D-CTC condition has originally been proposed by David Deutsch as a condition on states of a quantum communication network that contains “backward time-steps” in some of its branches. It has been

Quantum causality in closed timelike curves

Although general relativity allows the existence of closed timelike curves (CTCs), self-consistency problems arise (the ‘grandfather paradox’ among others). It is known that quantum mechanical