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Santo Andre, Brazil

Universidade Federal do ABC is a Brazilian institution of higher learning based in Santo André, with operations scheduled for several municipalities in the ABC region, all in the state of São Paulo. The chairman of the committee that formulated the proposal of the university, Luiz Bevilacqua, who turned out to be its second rector, claimed that it will allow its students to be creative and daring. The UFABC is the only federal university in Brazil with 100% of Ph. Wikipedia.


Nishi C.C.,Federal University of ABC
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We classify explicitly all the possible generalized CP symmetries that are definable in Δ(27) flavor models. In total, only 12 transformations are possible. We also show interesting consequences of considering some of them as residual symmetries of the neutrino sector. © 2013 American Physical Society. Source


Konoplya R.A.,Kyoto University | Konoplya R.A.,University of Tubingen | Zhidenko A.,University of Sao Paulo | Zhidenko A.,Federal University of ABC
Reviews of Modern Physics | Year: 2011

Perturbations of black holes, initially considered in the context of possible observations of astrophysical effects, have been studied for the past 10 years in string theory, brane-world models, and quantum gravity. Through the famous gauge/gravity duality, proper oscillations of perturbed black holes, called quasinormal modes, allow for the description of the hydrodynamic regime in the dual finite temperature field theory at strong coupling, which can be used to predict the behavior of quark-gluon plasmas in the nonperturbative regime. On the other hand, the brane-world scenarios assume the existence of extra dimensions in nature, so that multidimensional black holes can be formed in a laboratory experiment. All this stimulated active research in the field of perturbations of higher-dimensional black holes and branes during recent years. In this review recent achievements on various aspects of black hole perturbations are discussed such as decoupling of variables in the perturbation equations, quasinormal modes (with special emphasis on various numerical and analytical methods of calculations), late-time tails, gravitational stability, anti-de Sitter/conformal field theory interpretation of quasinormal modes, and holographic superconductors. We also touch on state-of-the-art observational possibilities for detecting quasinormal modes of black holes. © 2011 American Physical Society. Source


Shchesnovich V.S.,Federal University of ABC
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014

The boson sampler proposed by Aaronson and Arkhipov is a nonuniversal quantum computer, which can serve as evidence against the extended Church-Turing thesis. It samples the probability distribution at the output of a linear unitary optical network with indistinguishable single photons at the input. Four experimental groups have already tested their small-scale prototypes with up to four photons. A boson sampler with a few dozens of single photons is believed to be hard to simulate on a classical computer. For scalability of a realistic boson sampler with current technology it is necessary to know the effect of the photon mode mismatch on its operation. Here a nondeterministic model of the boson sampler is analyzed, which employs partially indistinguishable single photons emitted by identical sources. A sufficient condition on the average mutual fidelity 〈F〉 of the single photons is found, which guarantees that the realistic boson sampler outperforms the classical computer. Moreover, the boson-sampler computer with partially indistinguishable single photons is scalable and has more power than classical computers when the single-photon mode mismatch 1-〈F〉 scales as O(N-3/2) with the total number of photons N. © 2014 American Physical Society. Source


Kupriyanov V.G.,Federal University of ABC
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

In this paper we discuss classical aspects of spinor field theory on the coordinate dependent noncommutative space-time. The noncommutative Dirac equation describing spinning particle in an external vector field and the corresponding action principle are proposed. The specific choice of a star product allows us to derive a conserved noncommutative probability current and to obtain the energy-momentum tensor for free noncommutative spinor field. Finally, we consider a free noncommutative Dirac fermion and show that if the Poisson structure is Lorentz-covariant, the standard energy-momentum dispersion relation remains valid. © 2014 The Authors. Source


Shchesnovich V.S.,Federal University of ABC
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015

We generalize an approach for description of multiphoton experiments with multiport unitary linear optical devices, started in Phys. Rev. A 89, 022333 (2014)PLRAAN1050-294710.1103/PhysRevA.89.022333 with single photons in mixed spectral states, to arbitrary (multiphoton) input and arbitrary photon detectors. We show that output probabilities are always given in terms of the matrix permanents of the Hadamard product of a matrix built from the network matrix and matrices built from the spectral state of photons and spectral sensitivities of detectors. Moreover, in the case of input with up to one photon per mode, the output probabilities are given by a sum (or integral) with each term being the absolute value squared of such a matrix permanent. We conjecture that, for an arbitrary multiphoton input, zero output probability of an output configuration is always the result of an exact cancellation of quantum transition amplitudes of completely indistinguishable photons (a subset of all input photons) and, moreover, is independent of coherence between only partially indistinguishable photons. The conjecture is supported by examples. Furthermore, we propose a measure of partial indistinguishability of photons which generalizes Mandel's observation, and find the law of degradation of quantum coherence in a realistic boson-sampling device with increase of the total number of photons and/or their "classicality parameter." © 2015 American Physical Society. Source

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