Proper relativistic position operators in 1+1 and 2+1 dimensions
- URL: http://arxiv.org/abs/2007.04770v1
- Date: Wed, 24 Jun 2020 06:37:25 GMT
- Title: Proper relativistic position operators in 1+1 and 2+1 dimensions
- Authors: Taeseung Choi
- Abstract summary: parity operator plays a crucial role in deriving wave equations in both theories.
In 1+1 dimensions the particle position operator, not the canonical position operator, provides the conserved Lorentz generator.
In 2+1 dimensions, the sum of the orbital angular momentum given by the canonical position operator and the spin angular momentum becomes a constant of motion.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We have revisited the Dirac theory in 1+1 and 2+1 dimensions by using the
covariant representation of the parity-extended Poincar\'e group in their
native dimensions. The parity operator plays a crucial role in deriving wave
equations in both theories. We studied two position operators, a canonical one
and a covariant one that becomes the particle position operator projected onto
the particle subspace. In 1+1 dimensions the particle position operator, not
the canonical position operator, provides the conserved Lorentz generator. The
mass moment defined by the canonical position operator needs an additional
unphysical spin-like operator to become the conserved Lorentz generator in 1+1
dimensions. In 2+1 dimensions, the sum of the orbital angular momentum given by
the canonical position operator and the spin angular momentum becomes a
constant of motion. However, orbital and spin angular momentum do not conserve
separately. On the other hand the orbital angular momentum given by the
particle position operator and its corresponding spin angular momentum become a
constant of motion separately.
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