Off-shell photon distribution amplitudes in the low-energy effective theory of QCD

Abstract

Based on the principle of Lorentz covariance the transition matrix elements from an off-shell photon state to the vacuum are decomposed into the light-cone photon distribution amplitudes (DAs), in which only two transversal DAs survive in the on-shell limit. The eight off-shell lightcone photon DAs corresponding to chiral odd and chiral even up to twist four, and the corresponding coupling constants are studied systematically in the instanton vacuum model of quantum chromodynamics (QCD). The various individual photon DAs multiplied by their corresponding coupling constants are expressed in terms of the correlation functions, which are connected with the spectral densities of an effective quark propagator and then evaluated in the low-energy effective theory derived from the instanton vacuum model of QCD. The explicit analytical expressions and the numerical results for the photon DAs and their coupling constants are given.

Thermodynamic consequences of well-known regular black holes under modified first law

“…In [57], In [57], Eqs. (43) and (44) are the critical masses which come into the view of the analysis of horizons for eight different cases. The cases, when M < M c1 and M = 0, the cosmological horizon appears.…”

“…Kubiznak and Mann acquired this concept and investigated the thermodynamics of the charged AdS BH in the extended phase space [26]. In this way, the investigation on thermodynamics of the many BHs has been made and many significative critical phenomena were found in [15,[27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][43][44][45][46][47][48][49][50][51]. Hansen et al modified the first law of thermodynamics by using the radial Einstein's equation at the Kerr BH by the surface tension [52].…”

Charged dilatonic black holes in gravity’s rainbow

“…In addition, it was shown that a case of ensemble dependency exists for charged three-dimensional black holes which could be removed by considering the cosmological constant as a thermodynamical variable [124]. The thermodynamical critical behavior of black holes in the presence of different matter fields and gravities has been investigated in the literature [91][92][93][94][95][96][97][98][99][100][101][102][103][104][105][106][107][108][109].…”

$$P$$ P – $$V$$ V criticality of AdS black hole in the Einstein–Maxwell–power-Yang–Mills gravity

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