Classical Hamiltonian time crystals–general theory and simple examples

We focus on a Hamiltonian system with a continuous symmetry, and dynamics that takes place on a presymplectic manifold. We explain how the symmetry can become spontaneously broken by a time crystal, that we define as the minimum of the available mechanical free energy that is simultaneously a time d...

Full description

Bibliographic Details
Main Authors: Jin Dai, Antti J Niemi, Xubiao Peng
Format: Article
Language:English
Published: IOP Publishing 2020-01-01
Series:New Journal of Physics
Subjects:
Online Access:https://doi.org/10.1088/1367-2630/aba8d3
_version_ 1797750364735275008
author Jin Dai
Antti J Niemi
Xubiao Peng
author_facet Jin Dai
Antti J Niemi
Xubiao Peng
author_sort Jin Dai
collection DOAJ
description We focus on a Hamiltonian system with a continuous symmetry, and dynamics that takes place on a presymplectic manifold. We explain how the symmetry can become spontaneously broken by a time crystal, that we define as the minimum of the available mechanical free energy that is simultaneously a time dependent solution of Hamilton’s equation. The mathematical description of such a timecrystalline spontaneous symmetry breaking builds on concepts of equivariant Morse theory in the space of Hamiltonian flows. As an example we analyze a general family of timecrystalline Hamiltonians that is designed to model polygonal, piecewise linear closed strings. The vertices correspond to the locations of pointlike interaction centers; the string is akin a chain of atoms, that are joined together by covalent bonds, modeled by the links of the string. We argue that the timecrystalline character of the string can be affected by its topology. For this we show that a knotty string is usually more timecrystalline than a string with no self-entanglement. We also reveal a relation between phase space topology and the occurrence of timecrystalline dynamics. For this we show that in the case of three point particles, the presence of a time crystal can relate to a Dirac monopole that resides in the phase space. Our results propose that physical examples of Hamiltonian time crystals can be realized in terms of closed, knotted molecular rings.
first_indexed 2024-03-12T16:31:43Z
format Article
id doaj.art-a5f052efa16641238d137760cdfcf8ac
institution Directory Open Access Journal
issn 1367-2630
language English
last_indexed 2024-03-12T16:31:43Z
publishDate 2020-01-01
publisher IOP Publishing
record_format Article
series New Journal of Physics
spelling doaj.art-a5f052efa16641238d137760cdfcf8ac2023-08-08T15:27:30ZengIOP PublishingNew Journal of Physics1367-26302020-01-0122808500610.1088/1367-2630/aba8d3Classical Hamiltonian time crystals–general theory and simple examplesJin Dai0Antti J Niemi1https://orcid.org/0000-0003-3408-5834Xubiao Peng2Nordita, Stockholm University , Roslagstullsbacken 23, SE-106 91 Stockholm, SwedenNordita, Stockholm University , Roslagstullsbacken 23, SE-106 91 Stockholm, Sweden; Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Fédération Denis Poisson, Université de Tours , Parc de Grandmont, F37200, Tours, France; School of Physics, Beijing Institute of Technology , Haidian District, Beijing 100081, People’s Republic of ChinaSchool of Physics, Beijing Institute of Technology , Haidian District, Beijing 100081, People’s Republic of ChinaWe focus on a Hamiltonian system with a continuous symmetry, and dynamics that takes place on a presymplectic manifold. We explain how the symmetry can become spontaneously broken by a time crystal, that we define as the minimum of the available mechanical free energy that is simultaneously a time dependent solution of Hamilton’s equation. The mathematical description of such a timecrystalline spontaneous symmetry breaking builds on concepts of equivariant Morse theory in the space of Hamiltonian flows. As an example we analyze a general family of timecrystalline Hamiltonians that is designed to model polygonal, piecewise linear closed strings. The vertices correspond to the locations of pointlike interaction centers; the string is akin a chain of atoms, that are joined together by covalent bonds, modeled by the links of the string. We argue that the timecrystalline character of the string can be affected by its topology. For this we show that a knotty string is usually more timecrystalline than a string with no self-entanglement. We also reveal a relation between phase space topology and the occurrence of timecrystalline dynamics. For this we show that in the case of three point particles, the presence of a time crystal can relate to a Dirac monopole that resides in the phase space. Our results propose that physical examples of Hamiltonian time crystals can be realized in terms of closed, knotted molecular rings.https://doi.org/10.1088/1367-2630/aba8d3time crystalsHamiltonian dynamicspresymplectic geometryequivariant Morse theory
spellingShingle Jin Dai
Antti J Niemi
Xubiao Peng
Classical Hamiltonian time crystals–general theory and simple examples
New Journal of Physics
time crystals
Hamiltonian dynamics
presymplectic geometry
equivariant Morse theory
title Classical Hamiltonian time crystals–general theory and simple examples
title_full Classical Hamiltonian time crystals–general theory and simple examples
title_fullStr Classical Hamiltonian time crystals–general theory and simple examples
title_full_unstemmed Classical Hamiltonian time crystals–general theory and simple examples
title_short Classical Hamiltonian time crystals–general theory and simple examples
title_sort classical hamiltonian time crystals general theory and simple examples
topic time crystals
Hamiltonian dynamics
presymplectic geometry
equivariant Morse theory
url https://doi.org/10.1088/1367-2630/aba8d3
work_keys_str_mv AT jindai classicalhamiltoniantimecrystalsgeneraltheoryandsimpleexamples
AT anttijniemi classicalhamiltoniantimecrystalsgeneraltheoryandsimpleexamples
AT xubiaopeng classicalhamiltoniantimecrystalsgeneraltheoryandsimpleexamples