C-P-T Fractionalization

There are many Lie groups used in physics, including the Lorentz group of special relativity, the spin groups (relativistic and non-relativistic) and the gauge groups of quantum electrodynamics and the weak and strong nuclear forces. Various grand unified theories use larger Lie groups in different attempts to unify some of these groups into something more fundamental. There are also a number of finite symmetry groups that are related to the finite number of distinct elementa...

We review the methodology to theoretically treat parity-time- ($\mathcal{PT}$-) symmetric, non-Hermitian quantum many-body systems... (For the full abstract see paper)

We develop a systematic theory of symmetry fractionalization for fermionic topological phases of matter in (2+1)D with a general fermionic symmetry group $G_f$. In general $G_f$ is a central extension of the bosonic symmetry group $G_b$ by fermion parity, $(-1)^F$, characterized by a non-trivial cohomology class $[\omega_2] \in \mathcal{H}^2(G_b, \mathbb{Z}_2)$. We show how the presence of local fermions places a number of constraints on the algebraic data that defines the ac...

On the basis of the invariance of Dirac equation Lu(x,c)=0 with respect to the inversion of the speed of light Q:(x,c)=(x,-c), it is shown that the relationship [C,PTQ]u(x,c)=0 between the transformations of the charge conjugation C, the space inversion P, the time reversal T and the inversion of the speed of light Q is true. The charge conjugation in quantum theory may be interpreted as the consequence of the discrete symmetries reflecting the fundamental properties of space...

This dissertation is about The history of quaternions and their associated rotation groups as it relates to theoretical physics.

Recently, we presented a new class of quantum-mechanical Hamiltonians which can be written as the $F^{th}$ power of a conserved charge: $H=Q^F$ with $F=2,3,...\,.$ This construction, called fractional supersymmetric quantum mechanics, was realized in terms of a paragrassmann variable $\theta$ of order $F$, which satisfies $\theta^F=0$. Here, we present an alternative realization of such an algebra in which the internal space of the Hamiltonians is described by a tensor produc...

There is a unique finite group that lies inside the 2-dimensional unitary group but not in the special unitary group, and maps by the symmetric square to an irreducible subgroup of the 3-dimensional real special orthogonal group. In an earlier paper I showed how the representation theory of this group over the real numbers gives rise to much of the structure of the standard model of particle physics, but with a number of added twists. In this theory the group is quantised, bu...

It is known that in Lorentz-violating effective field theory, there is a classical equivalence between certain coefficients ($c$ and $f$), in spite of the fact that the operators the two types of coefficients describe appear to have opposite behaviors under $\textbf{CPT}$. This paper is a continuation of previous work extending this equivalence to the quantum level: generalizing the explicit spinorial point transformations that interconvert the $c$ and $f$ terms; demonstratin...

We develop a theory of charge-parity-time (CPT) frameness resources to circumvent CPT-superselection. We construct and quantify such resources for spin~0, $\frac{1}{2}$, 1, and Majorana particles and show that quantum information processing is possible even with CPT superselection. Our method employs a unitary representation of CPT inversion by considering the aggregate action of CPT rather than the composition of separate C, P and T operations, as some of these operations in...

The paper discusses the following topics: spinor coverings for the full Lorentz group, intrinsic parity of fermions, Majorana fermions, spinor structure of space models, two types of spacial spinors, parametrization of spinor spaces by curvilinear coordinates, manifestation of spinor space structure in classifying solutions of the quantum-mechanical equations and in the matrix elements for physical quantities.