相关论文: Extremal black disks in QCD
We point out that perturbative evolution in QCD at three loops generates a strange-antistrange asymmetry s(x)-sbar(x) in the nucleon's sea just from the fact that the nucleon has non-vanishing up and down quark valence densities. The…
The structure function of a heavy quark in a heavy hadron in electroproduction is calculated from QCD. Its deviation from the parton model prediction (a delta function) is shown to be governed by a shape function, similar to the one…
We study the cold and dense regime in the phase diagram of two-color QCD with heavy quarks within a three-dimensional effective theory for Polyakov loops. This theory is derived from two-color QCD in a combined strong-coupling and hopping…
Scalar fields pervade theoretical physics and are a fundamental ingredient to solve the dark matter problem, to realize the Peccei-Quinn mechanism in QCD or the string-axiverse scenario. They are also a useful proxy for more complex matter…
We present numerical calculations of spectra and structure of accretion disks models appropriate for near-Eddington luminosity black hole X-ray binaries (BHB). Our work incorporates non-zero torque at the ISCO as well as several dissipation…
We discuss results for heavy quark correlations in next-to-leading order QCD in deep inelastic electroproduction.
The discovery of high redshift quasars represents a challenge to the origin of supermassive black holes. Here, two evolutionary scenarios are considered. The first one concerns massive black holes in the local universe, which in a large…
We examine radiation and its effects on accretion disks orbiting astrophysical black holes. These disks are thermally radiating and can be geometrically and optically thin or thick. In this first paper of the series, we discuss the physics…
An explicit construction of the proton wave function is outlined in the high momentum limit of QCD dominated by a direct $qqq$ force, one generated by hooking the ends of a $ggg$ vertex to 3 distinct ${\bar q}gq$ vertices, thus making up a…
Adding two color sextet quarks to QCD gives many special features. The high-energy S-Matrix, constructed via reggeon diagrams and chiral anomalies, contains the Critical Pomeron and electroweak symmetry breaking is produced, by sextet…
Photon absorption by a quark in one nucleon followed by its high momentum transfer interaction with a quark in the other may produce two nucleons with high relative momentum. We sum the relevant quark rescattering diagrams, to show that the…
It is argued that it is valid to use QCD sum rules to determine the scalar and pseudoscalar two-point functions at zero momentum, which in turn determine the ratio of the strange to non-strange quark condensates $R_{su} = \frac{<\bar{s}…
The changes a (negative) tidal charge causes at the phenomenon of superradiance which occurs around rotating black holes are investigated. This is made by computing the amplification factors of massless scalar waves being scattered by the…
As shown recently 2d quantum gravity theories -- including spherically reduced Einstein-gravity -- after an exact path integral of its geometric part can be treated perturbatively in the loops of (scalar) matter. Obviously the classical…
We compute two-loop helicity amplitudes in QCD for diphoton production through quark- and gluon-initiated channels, accounting for a massive internal quark loop by keeping its full mass dependence. Using physical projectors, we directly…
Saturation is expected to occur when a high density of partons (mainly gluons)- or equivalently strong fields in Quantum Chromodynamics (QCD) - is realized in the weak coupling regime. A way to reach saturation is through the high-energy…
We calculate the structure of accretion disc around a rapidly rotating black hole with a super-Eddington accretion rate. The luminosity and height of the disc are reduced by the advection effect. In the case of a large viscosity parameter,…
Photon absorption by a quark in one nucleon followed by its high momentum transfer interaction with a quark in the other may produce two final-state nucleons with high relative momentum. We sum the relevant quark rescattering diagrams, to…
We follow the evolution of the Black Hole mass function in the assumption that mass accretion onto a massive BH is the powering mechanism of AGN activity. With reasonable assumptions suggested by current knowledge, it is possible to…
We examine five dimensional extreme black holes with three charges in the matrix model. We build configurations of the 5+1 super Yang-Mills theory which correspond to black holes with transverse momentum charge. We calculate their mass and…