An alternative way to explain how non-commutativity arises in the bosonic string theory

In this work we will investigate how the non-commutativity arises into the string theory, \textit{i.e.}, how the bosonic string theory attaches to a D3-brane in the presence of magnetic fields. In order to accomplish the proposal, we departure from the commutative two-dimensional harmonic oscillator, which after the application of the general Bopp's shifts Matrix Method, the non-commutative version of the two-dimensional harmonic oscillator is obtained. After that, this non-commutative harmonic oscillator will be mapped into the bosonic string theory in the light cone frame, which it now appears as a bosonic string theory attached to a D3-brane

Noncommutative approach to diagnose degenerate Higgs bosons at 125 GeV

We propose a noncommutative (NC) version for a global O(2) scalar field theory, whose damping feature is introduced into the scalar field theory through the NC parameter. In this context, we investigate how noncommutative drives spontaneous symmetry breaking (SSB) and Higgs-Kibble mechanisms and how the damping feature workout. Indeed, we show that the noncommutativity plays an important role in such mechanisms, i.e., the Higgs mass and VEV dependent on NC parameter. After that, it is explored the consequences of noncommutativity dependence of Higgs mass and VEV: for the first, it is shown that there are a mass-degenerate Higgs bosons near 126.5 GeV, parametrized by the noncommutativity; for the second, the gauge fields gain masses that present a noncommutativity contribution.Comment: 13 pages, 2 figure

Measurement strategy for spatially encoded photonic qubits

We propose a measurement strategy which can, probabilistically, reproduce the statistics of any observable for spatially encoded photonic qubits. It comprises the implementation of a two-outcome positive operator-valued measure followed by a detection in a fixed transverse position, making the displacement of the detection system unnecessary, unlike previous methods. This strategy generalizes a scheme recently demonstrated by one of us and co-workers restricted to measurement of observables with equatorial eigenvectors only. The method presented here can be implemented with the current technology of programmable multipixel liquid-crystal displays. In addition, it can be straightforwardly extended to high-dimensional qudits and may be a valuable tool in optical implementations of quantum information protocols with spatial qubits and qudits.Comment: 5 pages, 2 figures. Published versio

Noncommutative Mapping from the symplectic formalism

The Bopp's shifts will be generalized through symplectic formalism. A special procedure, like a "diagonalization", which drives the completely deformed symplectic matrix to the standard symplectic form was found as suggested by Faddeev-Jackiw. Consequently, the correspondent transformation matrix guides the mapping from commutative to noncommutative (NC) phase-space coordinates. The Bopp's shifts may be directly generalized from this mapping. In this context, all the NC and scale parameters, introduced into the brackets, will be lifted to the Hamiltonian. Well known results, obtained using $\star$-product, will be reproduced without to consider that the NC parameters are small$(<<1)$. Besides, it will be shown that different choices for NC algebra among the symplectic variables generates distinct dynamical systems, which they may not even connect with each other, and that some of them can preserve, break or restore the symmetry of the system. Further, we will also discuss the charge and mass rescaling in a simple model.Comment: 24 page

Noncommutative approach to disclose a Higgs group

A noncommutative(NC) version for a global $O(N)$ scalar field theory is proposed and an alternative investigation about how noncommutative drives spontaneous symmetry breaking (SSB) is explored. Indeed, we show that the noncommutativity plays an important role in such mechanism, i.e., it is possible to show that there is a Higgs group with no more than two Higgs bosons. In this scenario, we establish two mutually exclusive options: one Higgs boson with mass at 125 GeV and other at 750 GeV -- 2 TeV excess does not imply a 2 TeV mass resonance -- or two Higgs bosons with mass-degenerate near 125~GeV, where 2 TeV and 750 GeV excesses do not imply a 2 TeV and 750 GeV masses resonance.Comment: arXiv admin note: text overlap with arXiv:1903.0972

A Z′Z'-model and the magnetism of a dark fermion candidate

Our contribution sets out to investigate the phenomenology of a gauge model based on an $SU_{L}(2) \times U_{R}(1)_{Q} \times U(1)_{Q'}$-symmetry group. The model can accommodate, through its symmetry-breaking pattern, a candidate to a heavy $Z'$-boson at the TeV-scale. The extended Higgs sector introduces a heavy scalar whose mass lies in the region 1.2-3.7 \, \mbox{TeV}. The fermion sector includes an exotic candidate to Dark Matter that mixes with the right-handed neutrino component in the Higgs sector, so that the whole field content ensures the cancellation of the $U(1)$-quiral anomaly. The masses are fixed according to the particular way the symmetry breaking takes place. In view of the possible symmetry breakdown pattern, we study the phenomenological implications in a high-energy scenario. We worek out the magnetic dipole momentum (MDM) of the exotic fermion and the transition MDM due to its mixing with the right-neutrino.Comment: 12 pages, 7 figures, 1 tabl

Quantum teleportation via maximum-confidence quantum measurements

We investigate the problem of teleporting unknown qudit states via pure quantum channels with nonmaximal Schmidt rank. This process is mapped to the problem of discriminating among nonorthogonal symmetric states which are linearly dependent and equally likely. It is shown that by applying an optimized maximum-confidence (MC) measurement for accomplishing this task, one reaches the maximum possible teleportation fidelity after a conclusive event in the discrimination process, which in turn occurs with the maximum success probability. In this case, such fidelity depends only on the Schmidt rank of the channel and it is larger than the optimal one achieved, deterministically, by the standard teleportation protocol. Furthermore, we show that there are quantum channels for which it is possible to apply a k-stage sequential MC measurement in the discrimination process such that a conclusive event at any stage leads to a teleportation fidelity above the aforementioned optimal one and, consequently, increases the overall success probability of teleportation with a fidelity above this limit.Comment: 14 pages, 6 figure

Parametric separation of symmetric pure quantum states

Quantum state separation is a probabilistic map that transforms a given set of pure states into another set of more distinguishable ones. Here we investigate such a map acting onto uniparametric families of symmetric linearly dependent or independent quantum states. We obtained analytical solutions for the success probability of the maps--which is shown to be optimal--as well as explicit constructions in terms of positive operator valued measures. Our results can be used for state discrimination strategies interpolating continuously between minimum-error and unambiguous (or maximum-confidence) discrimination, which, in turn, have many applications in quantum information protocols. As an example, we show that quantum teleportation through a nonmaximally entangled quantum channel can be accomplished with higher probability than the one provided by unambiguous (or maximum-confidence) discrimination and with higher fidelity than the one achievable by minimum-error discrimination. Finally, an optical network is proposed for implementing parametric state separation.Comment: 13 pages, 5 figure

Experimental minimum-error quantum-state discrimination in high dimensions

Quantum mechanics forbids perfect discrimination among nonorthogonal states through a single shot measurement. To optimize this task, many strategies were devised that later became fundamental tools for quantum information processing. Here, we address the pioneering minimum-error (ME) measurement and give the first experimental demonstration of its application for discriminating nonorthogonal states in high dimensions. Our scheme is designed to distinguish symmetric pure states encoded in the transverse spatial modes of an optical field; the optimal measurement is performed by a projection onto the Fourier transform basis of these modes. For dimensions ranging from D = 2 to D = 21 and nearly 14000 states tested, the deviations of the experimental results from the theoretical values range from 0.3% to 3.6% (getting below 2% for the vast majority), thus showing the excellent performance of our scheme. This ME measurement is a building block for high-dimensional implementations of many quantum communication protocols, including probabilistic state discrimination, dense coding with nonmaximal entanglement, and cryptographic schemes.Comment: 13 pages, 13 figure

BPS Maxwell-Chern-Simons-like vortices in a Lorentz-violating framework

We have analyzed Maxwell-Chern-Simons-Higgs BPS vortices in a Lorentz-violating CPT-odd context. The Lorentz violation induces profiles with a conical behavior at the origin. For some combination of the coefficients for Lorentz violation there always exists a sufficiently large winding number for which the magnetic field flips its sign.Comment: Presented at the Sixth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, June 17-21, 201