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Published on: April 14, 2020
Discrete Lorentz symmetry and discrete spacetime translational symmetry in two- and three-dimensional crystals
Xiuwen Li1, Jiaxue Chai1, Huixian Zhu1
1Department of Physics, Zhejiang Normal University, Jinhua 321004, People's Republic of China.
Abstract:
As is well known, crystals have discrete space translational symmetry. It was recently noticed that one-dimensional crystals possibly have discrete Poincaré symmetry, which contains discrete Lorentz and discrete time translational symmetry as well. In this paper, we classify the discrete Poincaré groups on two- and three- dimensional Bravais lattices. They are the candidate symmetry groups of two- or three-dimensional crystals, respectively. The group is determined by an integer generator g, and it reduces to the space group of crystals at g = 2.
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