Related papers: Majorana representation for mixed states
We show that any model with a homogeneous relationship among elements of the neutrino mass matrix with one mass hierarchy yields predictions for the oscillation parameters and Majorana phases similar to those given by a model with the same…
Coherent states in a projected Hilbert space have many useful properties. When there are conserved quantities, a representation of the entire Hilbert space is not necessary. The same issue arises when conditional observations are made with…
For the tensor of coherences parametrization of a multiqubit density operator, we provide an explicit formulation of the corresponding unitary dynamics at infinitesimal level. The main advantage of this formalism (clearly reminiscent of the…
With the help of a useful mathematical tool, the polar decomposition of closed operators, and a simple observation, i.e. the unique relation between tensor-product states and compact operators, we manage to give a compact and coherent…
A many body Hamiltonian comprising pairing, quadrupole-quadrupole and spin-spin interaction is treated within a projected spherical basis with the aim of describing the detailed structure of the magnetic states of orbital and spin-flip…
We propose a mechanism to describe how a physical quantity, which initially can take continuous values, is restricted within some discrete values after a measurement. As an example of the present theory, in which interplay between coherence…
Consider a spin s prepared in a pure state. It is shown that, generically, the moduli of the (2s+1) spin components along three directions in space determine the state unambiguously. These probabilities are accessible experimentally by…
A parameterization of the density operator, a coherence vector representation, which uses a basis of orthogonal, traceless, Hermitian matrices is discussed. Using this parameterization we find the region of permissible vectors which…
We present exact analytic formulae which describe the interaction of multistate quantum systems possessing the Majorana and Morris-Shore dynamic symmetries with a train of pulses. The pulse train field can be viewed as repeated interactions…
We show that the pointer basis distinguished by collisional decoherence consists of exponentially localized, solitonic wave packets. Based on the orthogonal unraveling of the quantum master equation, we characterize their formation and…
We systematically analyze the Dirac and the Majorana mass matrices in seesaw models with two heavy right-handed neutrinos. We perform thorough classification of the vanishing matrix elements which are compatible with the results from the…
Efficient oscillations between ordinary (active) and sterile neutrinos can occur only if Dirac and Majorana mass terms exist which are both small and comparable. It is shown that this can occur naturally in a class of string models, in…
We present a formalism that extends the Majorana-construction to arbitrary spin (j,0)+(0,j) representation spaces. For the example case of spin-1, a wave equation satisfied by the Majorana-like (1,0)+(0,1) spinors is constructed and its…
We propose a realistic model with Majorana neutrinos in the framework of unifying the three generations of fermions by point interactions in an extra dimension. This model can simultaneously explain the origin of fermion generations,…
We establish reflection positivity for Gibbs trace states defined by a certain class of Hamiltonians that describe the interaction of Majoranas on a lattice. These Hamiltonians may include many-body interactions, as long as the signs of the…
In contrast to the canonically conjugate variates $q$,$p$ representing the position and momentum of a particle in the phase space distributions, the three Cartesian components, $J_{x}$,$J_{y}$, $J_{z}$ of a spin-$j$ system constitute the…
Due to the standard electroweak model we have become accustomed to think about a neutrino $\nu$ and its antineutrino $\bar \nu$ as distinct particles. However, it has long been recognized that the apparent distinction between them may be…
We consider the bosonic fields which describe a particle which may exist in states with spins one and zero with different masses. All the linearly independent solutions of the equation for a free particle are obtained in the form of the…
We express the positive partial transpose (PPT) separability criterion for symmetric states of multi-qubit systems in terms of matrix inequalities based on the recently introduced tensor representation for spin states. We construct a matrix…
A class of vector coherent states is derived with multiple of matrices as vectors in a Hilbert space, where the Hilbert space is taken to be the tensor product of several other Hilbert spaces. As examples vector coherent states with…