Searcharxiv⌕ Search

arXiv subjects

Jakub Rembielinski

Publications and source records attributed to Jakub Rembielinski.

18 recordsLinked to original sources
arXiv2023

Possible explanation of not observing ultra-high energy cosmic neutrinos

Assuming that neutrinos are spacelike (tachyonic) fermions, we calculate width for the kinematically allowed, lepton number conserving, three-body decay $ν_α\rightarrow ν_α \; ν_β \barν_β$ in the Standard Model. Decays of tachyonic neutrinos over cosmological distances can lead to a reduction of the neutrino flux in the high-energy end of the spectrum. We estimate upper limits on the spacelike neutrino mass based on the PeV-energy cosmological neutrino events observed in the IceCube experiment. These limits are close to those deduced from the measurements of $m_ν^2$ in the tritium-decay experiment KATRIN.

hep-ph↗
arXiv2022

New description of neutrino flavour evolution in solar matter

Assuming that the interacting neutrino and the solar matter can be treated as an open quantum system we formulate a formalism of neutrino state evolution in terms of the Bloch vector, obtained by solving a quasilinear extension of the von Neumann equation. We broaden the classical Wolfenstein formalism by means of exploiting the strictly linear von Neumann equation and reinterpreting the results in terms of the quantities appropriate for the quasilinear approach. We obtain similar predictions for the averaged neutrino survival probability measured on Earth in both approaches, differing by details inside the Sun where the quasilinear evolution predicts a suppression of oscillations. We discuss the issues of energy transfer between the neutrino and the Sun and the speed of the state evolution in both approaches.

hep-ph↗
arXiv2018

The photon and a preferred frame scenario

Structure of the space of photonic states is discussed in the context of a working hypothesis of existence of a preferred frame for photons. Two polarisation experiments are proposed to test the preferred frame scenario.

quant-ph↗
arXiv2012

"Meta" relativity: Against special relativity?

We introduce a Lorentz-covariant description of tachyons, free of inconsistencies. Our approach is based on an appropriate extension of the special relativity beyond the light barrier, owing to the freedom of synchronization of distant clocks.

gr-qc↗
arXiv2006

Einstein-Podolsky-Rosen correlations of Dirac particles - quantum field theory approach

We calculate correlation function in the Einstein--Podolsky--Rosen type of experiment with massive relativistic Dirac particles in the framework of the quantum field theory formalism. We perform our calculations for states which are physically interesting and transforms covariantly under the full Lorentz group action, i.e. for pseudoscalar and vector state.

quant-ph↗
arXiv2005

Entanglement and Tensor Product Decomposition for Two Fermions

The problem of the choice of tensor product decomposition in a system of two fermions with the help of Bogoliubov transformations of creation and annihilation operators is discussed. The set of physical states of the composite system is restricted by the superselection rule forbidding the superposition of fermions and bosons. It is shown that the Wootters concurrence is not proper entanglement measure in this case. The explicit formula for the entanglement of formation is found and its dependence on tensor product decompositions of the Hilbert space is discussed. It is shown that the set of separable states is narrower than in two-qubit case. Moreover, there exist states which are separable with respect to all tensor product decompositions of the Hilbert space.

quant-ph↗
arXiv2003

Photon polarization and Wigner's little group

To discuss one-photon polarization states we find an explicit form of the Wigner's little group element in the massless case for arbitrary Lorentz transformation. As is well known, when analyzing the transformation properties of the physical states, only the value of the phase factor is relevant. We show that this phase factor depends only on the direction of the momentum $\vec{k}/|\vec{k}|$ and does not depend on the frequency $k^0$. Finally, we use this observation to discuss the transformation properties of the linearly polarized photons and the corresponding reduced density matrix. We find that they transform properly under Lorentz group.

quant-ph↗
arXiv2002

Einstein-Podolsky-Rosen Correlations of Spin Measurements in Two Moving Inertial Frames

The formula for the correlation function of spin measurements of two particles in two moving inertial frames is derived within Lorentz-covariant quantum-mechanics formulated in the absolute synchronization framework. The results are the first exact Einstein-Podolsky-Rosen correlation functions obtained for Lorentz-covariant quantum-mechanical system in moving frames under physically acceptable conditions, i.e., taking into account the localization of the particles during the detection and using the spin opeartor with proper transformation properties under the action of the Lorentz group. Some special cases and approximations of the calculated correlation function are given. The resulting correlation function can be used as a basis for a proposal of a decisive experiment for a possible existence of a quantum-mechanical preferred frame.

quant-ph↗
arXiv2000

Superluminal Phenomena and the Quantum Preferred Frame

Motivated by a number of recent experiments, we discuss in this paper a speculative but physically admissible form and solutions of effective Maxwell-like equations describing propagation of electromagnetic field in a medium which ``feels'' a quantum preferred frame.

quant-ph↗
arXiv1998

Tritium Decay and the Hypothesis of Tachyonic Neutrinos

Numerous recent measurements indicate an excess of counts near the endpoint of the electron energy spectrum in tritium decay. We show that this effect is expected if the neutrino is a tachyon. Results of calculations, based on a unitary (causal) theory of tachyons, are presented. The hypothesis of tachyonic neutrinos also offers a natural explanation of the V-A structure of the weak leptonic current in neutrino interactions.

hep-ph↗
arXiv1997

Decays of spacelike neutrinos

In this paper we consider the hypothesis that neutrinos are fermionic tachyons with helicity 1/2. We propose an effective model of interactions of these neutrinos and analyze dominant effects under the above hypothesis: the three-body neutrino decay, the radiative decay and briefly discuss beta-decay with tachyonic antineutrino. We calculate the corresponding amplitudes and the mean life time for decays, as well as the differential decay width. In addition we apply the neutrino three-body decay to the solar neutrino problem and we obtain a remarkable change of energy spectrum of the neutrino flux at the Earth ground (assuming no neutrino oscillation). We compare the results with the Standard Solar Model predictions and solar neutrino experiments to estimate an upper bound for the taonic neutrino.

hep-ph↗
arXiv1996

The Preferred Frame and Poincare Symmetry

In this paper we describe a covariant canonical formalism for a free time-like (massive) as well as space-like (tachyonic) particle in the framework of nonstandard synchronization scheme. In this scheme one is able to introduce absolute causality without breaking the Poincaré invariance.

hep-th↗
arXiv1996

Tachyons and the preferred frames

Quantum field theory of space-like particles is investigated in the framework of absolute causality scheme preserving Lorentz symmetry. It is related to an appropriate choice of the synchronization procedure (definition of time). In this formulation existence of field excitations (tachyons) distinguishes an inertial frame (privileged frame of reference) via spontaneous breaking of the so called synchronization group. In this scheme relativity principle is broken but Lorentz symmetry is exactly preserved in agreement with local properties of the observed world. It is shown that tachyons are associated with unitary orbits of Poincaré mappings induced from $SO(2)$ little group instead of $SO(2,1)$ one. Therefore the corresponding elementary states are labelled by helicity. The cases of the helicity $λ= 0$ and $λ= \pm\frac{1}{2}$ are investigated in detail and a corresponding consistent field theory is proposed. In particular, it is shown that the Dirac-like equation proposed by Chodos et al., inconsistent in the standard formulation of QFT, can be consistently quantized in the presented framework. This allows us to treat more seriously possibility that neutrinos might be fermionic tachyons as it is suggested by experimental data about neutrino masses.

hep-th↗
arXiv1996

Experimental results and the hypothesis of tachyonic neutrinos

Recent measurements of the electron and muon neutrino masses squared are interpreted as an indication that neutrinos are faster than light particles -- tachyons. The tritium beta decay amplitude is calculated for the case of the tachyonic electron neutrino. Agreement of the theoretical prediction with the shape of the recently measured electron spectra is discussed. Amplitude for the three body decay of the tachyonic neutrino, $ν_{i} \rightarrow ν_{i} ν_{j} \overlineν_{j} $, is calculated. It is shown that this decay may explain the solar neutrino problem without assuming neutrino oscillations. Predictions for short and long baseline experiments are commented. Future experimental activities are suggested.

hep-ph↗
arXiv1993

Two-Dimensional Quantum PoincarÉ Group

Quantum Poincaré-Weyl group in two dimensional quantum Minkowski space-time is considered and an appriopriate relativistic kinematics is investigated. It is claimed that a consistent approach to the above questions demands a kind of a ``quantum geometry'' in the $q$-deformed space-time.

hep-th↗
arXiv1993

Non-commutative quantum dynamics

We described a $q$-deformation of a quantum dynamics in one dimension. We prove that there exists only one essential deforamtion of quantum dynamics.

hep-th↗