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Related papers: Time turns the universal kaleidoscope

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In several previous papers we have argued for a global and non-entropic approach to the problem of the arrow of time, according to which the ''arrow'' is only a metaphorical way of expressing the geometrical time-asymmetry of the universe.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Matias Aiello , Mario Castagnino , Olimpia Lombardi

We investigate the thermodynamic arrow of time in a time-symmetrically recollapsing universe by calculating quantum mechanically the entropy production of a massive scalar field. It is found that even though the Hamiltonian has a…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Sang Pyo Kim

The puzzle of the thermodynamic arrow of time reduces to the question of how the universe could have had lower entropy in the past. I show that no special entropy lowering mechanism (or fluctuation) is necessary. As a consequence of…

Statistical Mechanics · Physics 2015-05-13 L. S. Schulman

The local Lorentz and diffeomorphism symmetries of Einstein's gravitational theory are spontaneously broken by a Higgs mechanism by invoking a phase transition in the early Universe, at a critical temperature $T_c$ below which the symmetry…

General Relativity and Quantum Cosmology · Physics 2014-11-17 J. W. Moffat

Emergence of one-time-direction macroscopic evolution of a classical system of two mixed gases having different temperatures is derived and explained. The analysis performed at the microscopic level, where the time-symmetric laws of…

Classical Physics · Physics 2016-08-11 Krzysztof Rębilas

The spread of the time arrows from the environment to an observed subsystem is followed within a harmonic model. A similarity is pointed out between irreversibility and a phase with spontaneously broken symmetry. The causal structure of…

High Energy Physics - Theory · Physics 2012-06-26 Janos Polonyi

In the Schroedinger equation, time plays a special role as an external parameter. We show that in an enlarged system where the time variable denotes an additional degree of freedom, solutions of the Schroedinger equation give rise to…

Mathematical Physics · Physics 2014-11-20 Romeo Brunetti , Klaus Fredenhagen , Marc Hoge

We present a generic way of thinking about time machines from the view of a far away observer. In this model the universe consists of three (or more) regions: One containing the entrance of the time machine, another the exit and the…

Quantum Physics · Physics 2007-05-23 Frank Antonsen , Karsten Bormann

Within the framework of self-adjoint operator of time in non-relativistic quantum mechanics the equation describing change of the state of quantum system with respect to energy is introduced. The operator of time appears to be the generator…

Quantum Physics · Physics 2017-01-20 Slobodan Prvanovic

Time-asymmetric spacetime structures, in particular those representing black holes and the expansion of the universe, are intimately related to other arrows of time, such as the second law and the retardation of radiation. The nature of the…

General Relativity and Quantum Cosmology · Physics 2017-11-22 H. D. Zeh

In this paper we address the problem of the arrow of time from a cosmological point of view, rejecting the traditional entropic approach that defines the future direction of time as the direction of the entropy increase: from our…

Quantum Physics · Physics 2009-11-07 Mario Castagnino , Luis Lara , Olimpia Lombardi

The recent surge of interest in the origin of the temporal asymmetry of thermodynamical systems (including the accessible part of the universe itself) put forward two possible explanatory approaches to this age-old problem. Hereby we show…

Astrophysics · Physics 2007-05-23 Milan M. Cirkovic

Quantum mechanical unitarity in our universe is challenged both by the notion of the big bang, in which nothing transforms into something, and the expansion of space, in which something transforms into more something. This motivates the…

High Energy Physics - Theory · Physics 2022-02-08 Jordan Cotler , Andrew Strominger

In this paper we discuss the traditional approaches to the problem of the arrow of time. On the basis of this discussion we adopt a global and non-entropic approach, according to which the arrow of time has a global origin and is an…

Quantum Physics · Physics 2014-11-18 Mario Castagnino , Luis Lara , Olimpia Lombardi

Schroedinger's equation says that the Hamiltonian is the generator of time translations. This seems to imply that any reasonable definition of time operator must be conjugate to the Hamiltonian. Then both time and energy must have the same…

Quantum Physics · Physics 2019-12-19 Juan Leon , Lorenzo Maccone

Attempts to quantize general relativity encounter an odd problem. The Hamiltonian that normally generates time evolution vanishes in the case of general relativity as a result of diffeomorphism invariance. The theory seems to be saying that…

General Relativity and Quantum Cosmology · Physics 2009-04-23 Olaf Dreyer

The nature of time in quantum mechanics is closely related to the use of a complex, rather than say real, Hilbert space. This becomes particularly clear when considering quantum field theory in time dependent backgrounds, such as in…

General Relativity and Quantum Cosmology · Physics 2011-11-03 G. W. Gibbons

The discussion is limited to first-class parametrized systems, where the definition of time evolution and observables is not trivial, and to finite dimensional systems in order that technicalities do not obscure the conceptual framework.…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Petr Hajicek

The importance of the global nature of the arrow of time is shown. Classical Reichenbach diagram and quantum Bohm-Reichenbach diagram, for the universe are introduced. They are used to show the increase of entropy in closed systems, the…

Quantum Physics · Physics 2007-05-23 Mario A. Castagnino

Time flow has been embodied in time-dependent Schroedinger equation representing one of the foundations of quantum mechanics. Pauli's criticism (1933) has, however, indicated that the assumptions concerning representation Hilbert space have…

Quantum Physics · Physics 2007-05-23 Milos V. Lokajicek
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