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We apply the method of anomaly cancellation initiated by Robinson and Wilczek et al. to the Hawking radiation of rotating \(D\)-brane solutions of superstring theories. We obtain that their reduced field theories near their horizons are two-dimensional chiral field theories in a set of curved backgrounds. Therefore, we can calculate their angular momentum fluxes and energy-momentum fluxes from the method of anomaly cancellation. We obtain that the energy-momentum fluxes of the rotating \(D\)-branes compose thermal radiations, their thermal temperatures match with their Hawking temperatures obtained from black brane thermodynamics.

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In this work, we consider the problem of Unruh effect in the framework of Generalized Uncertainty Principle (GUP) of Quantum Gravity. The quantum gravitational effects at the Planck scale physics, as a consequence of GUP, induces the corrections to the Unruh radiation. In this set-up, we find an energy-dependent effective temperature which leads to a non-thermal emission in the Unruh radiation spectrum.

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We compute the leading terms of the spectral action for orientable three dimensional Bieberbach manifolds using two different methods: the Poisson summation formula and the perturbative expansion. Assuming that the cut-off function is not necessarily symmetric we find that the scale invariant part of the perturbative expansion might only differ from the spectral action of the flat three-torus by the value of the eta invariant.

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We provide a Finslerian extension of the Schwarzschild metric based on heuristic arguments. The proposed metric asymptotically approaches not the Minkowski space-time but the Bogoslovsky locally anisotropic space-time which arises naturally as a deformation of very special relativity.

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We show that there is only one physically acceptable vacuum state for quantum fields in de Sitter space-time which is left invariant under the action of the de Sitter–Lorentz group SO\((1,d)\) and supply its physical interpretation in terms of the Poincaré invariant quantum field theory (QFT) on one dimension higher Minkowski space-time. We compute correlation functions of the generalized vertex operator \(:e^{i\hat {S}(x)}:\), where \(\hat {S}(x)\) is a massless scalar field, on the \(d\)-dimensional de Sitter space and demonstrate that their limiting values at time-like infinities on de Sitter space reproduce correlation functions in \((d - 1)\)-dimensional Euclidean conformal field theory (CFT) on \(S^{~d-1}\) for scalar operators with arbitrary real conformal dimensions. We also compute correlation functions for a vertex operator \(e^{i\hat {S}(u)}\) on the Łobaczewski space and find that they also reproduce correlation functions of the same CFT. The massless field \(\hat {S}(u)\) is the nonlocal transform of the massless field \(\hat {S}(x)\) on de Sitter space introduced by one of us.

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Polarization of \( K^{~*}\) in the rare \(B \rightarrow K^{~*} \ell ^+ \ell ^-\) decay governed by the quark level transitions \(b \rightarrow s\), are investigated in the fourth quark generation model popularly known as SM4. We find that in this model due to the additional contributions coming from the heavy \(t'\) quark in the loop, the observables related to the polarization of \(K^{~*}\) deviate significantly from their SM values. Some of the physical observables are within the reach of LHCb experiment and search for such channels are strongly argued.

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We review our previous studies of truncated Mellin moments of parton distributions. We show in detail the derivation of the evolution equation for double truncated moments. The obtained splitting function has the same rescaled form as in a case of the single truncated moments. We apply the truncated moments formalism to QCD analyses of the spin structure functions of the nucleon, \(g_1\) and \(g_2\). We generalize the Wandzura–Wilczek relation in terms of the truncated moments and find new sum rules. We derive the DGLAP-like evolution equation for the twist-2 part of \(g_2\) and solve it numerically. We find also useful relations between the truncated and untruncated moments.

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In this work, we study the spin and flavor dependent SU\((6)\) violations in the strange and nonstrange baryons spectrum using a simple approach based on the Gürsey Radicati mass formula (GR). The average energy value of each SU\((6)\) multiplet is described using the SU\((6)\) invariant interaction given by a hypercentral potential. In this paper the hypercentral potential is regarded as a combination of the Coulombic-like term plus a linear confining term and we have added the harmonic oscillator potential. In fact, we have built up a potential scheme for the internal baryon structure which has three-body forces among three quarks. The results of our model (the combination of our proposed hypercentral Potential and generalized GR mass formula to description of the spectrum) show that the strange and nonstrange baryons spectrum are, in general, fairly well reproduced. The overall good description of the spectrum which we obtain shows that our model can also be used to give a fair description of the energies of the excited multiplets at least up to 2 GeV and negative-parity resonance. Moreover, we have shown that our model reproduces the position of the Roper resonances of the nucleon.

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We show that in the model of hidden sector of the Universe, interacting with the Standard-Model sector through the photonic portal, the Standard-Model Coulomb potential gets a tiny hidden-sector additive correction that might turn out to be either exciting or fatal for the verification of this model.

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The question of the relative size of two independent penguin amplitudes is studied using the data on the \(B^{+} \to \pi ^{+} K^{~*0}\) and \(B^+ \to K^{~+}\bar {K}^{~*0}\) decays. Our discussion involves a Regge-phenomenology-based estimate of SU\((3)\) breaking in the final quark-pair-creating hadronization process. The results are in agreement with earlier estimates of the relative size of the two penguins obtained from \(B^+ \to \pi ^+ K^{~0}, K^{~+} \bar {K}^{~0}\).

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We demonstrate that description of fluctuations observed in multiparticle production processes using Tsallis statistics approach (in which fluctuations are described by the nonextensivity parameter \(q\)) leads to a specific sum rule for parameters \(q\) seen in different observables which can be verified experimentally.

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We perform calculations for the binding energies and low-lying levels of \(^{10,11,12,13,14,15,16,17,18,19,20,21,22}\)C nuclei starting from the chiral N3LO nucleon–nucleon potential within the framework of the Hybrid Multideterminant scheme. The effective interaction is obtained using the Lee–Suzuki renormalization scheme applied to 4 and in some cases to 5, major harmonic oscillator shells. The results are compared with the experimental data.

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We study the phase diagram of strongly interacting matter including the inhomogeneous phase of Chiral Density Waves (CDW) within the Polyakov loop extended Nambu–Jona-Lasinio (PNJL) model. We discuss the phase structure taking into account density and flavour dependence of the Polyakov loop potential parameter and temperature dependence of the four-point coupling constant of the NJL model. It is shown that the CDW phase exists and that can be interpreted as a special realisation of quarkyonic matter. This fact is of particular interest because the existence of homogeneous quarkyonic matter is strongly constrained. This also indicates that the study of inhomogeneous phases at finite temperatures and baryon densities are of special importance.

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Nuclear matter equation of state and incompressibility are determined utilizing the relativistic density dependent Hadron field theory. Nuclear matter is studied at symmetric ground-state and at supernova collapse conditions, and pressure density of isentropic nuclear matter is determined as a function of the density at supernova collapse conditions. The value of the ground-state nuclear matter incompressibility is within the interval determined by isoscalar giant monopole resonance measurements and relativistic calculations, and the dependency of the coupling parameters on density leads to results closer to the results of calculations used in the study of supernova explosion than the results of other relativistic calculations.

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Using the volume-limited Main galaxy sample of the Sloan Digital Sky Survey Data Release 6 (SDSS DR6), we have explored the difference of clustering properties between Active Galactic Nucleus (AGN) host galaxies and star-forming galaxies. Our results preferentially show that AGN host galaxies have a lower fraction in isolated, close double and multiple systems than star-forming galaxies.

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We aim to consider impulsively-generated non-linear acoustic-gravity waves in a gravitationally-stratified stellar atmosphere. Two-dimensional hydrodynamic equations are solved numerically for an ideal plasma with a realistic temperature profile. The numerical results show that an initial pulse in vertical velocity excites a leading wave front which is followed by a dispersive wake, oscillating with a period close to the acoustic cut-off period \(P_{\rm ac}\) of the chromosphere. Impulses launched deeper within a low region of the stellar atmosphere result in a wake of smaller \(P_{\rm ac}\). They form quasi-periodic shocks traveling from the chromosphere to the corona. The interaction of the secondary (“rebound”) shocks with the chromosphere-corona transition region generates vortex motions, which may play important role the transition region dynamics.