相关论文: Exact Absorption Probability in the Extremal Six-D…
We investigate string amplitudes by using the partial modular transformation which we introduced in our previous works. This enables us to extract stringy threshold corrections from the full string amplitudes and interpret them in terms of…
An exact solution of the low-energy string theory representing static, spherical symmetric dyonic black hole is found. The solution is labeled by their mass, electric charge, magnetic charge and asymptotic value of the scalar dilaton. Some…
We consider a six-dimensional solitonic string solution described by a conformal chiral null model with non-trivial $N=4$ superconformal transverse part. It can be interpreted as a five-dimensional dyonic solitonic string wound around a…
In the context of electromagnetic absorption, it is obvious that for an infinite planar periodic structure illuminated by a plane wave, the maximum attainable absorptance, i.e., perfect absorption, is theoretically limited to 100% of the…
We investigate the transition between singular and non-singular geometries from the vantage point of perturbative field dynamics. In particular, we obtain the closed-form absorption probability for minimally-coupled massless scalars…
We present a simple closed expression for determining the condition for Coherent Perfect Absorption derived through electromagnetic wave treatment and interface boundary conditions. Apart from providing physical insight this expression can…
We revisit ADE minimal string theories, focusing on the D- and E-series minimal models coupled to Liouville theory. Unlike the A-series, whose duals are solvable two-matrix models, these theories are conjectured to correspond to unsolvable…
A black hole solution to low energy type IIA string theory which is extremal, non-supersymmetric, and carries 0- and 6-brane charge is presented. For large values of the charges it is metastable and a corresponding D-brane picture can be…
We study tree-level scattering processes of arbitrary string states using the DDF formalism and suitable coherent vertex operators. We obtain new exact compact formulae for heavy-heavy-light-light scattering amplitudes in open or closed…
We studied in detail the propagation of a massive tachyonic scalar field in the background of a five-dimensional ($5D$) Einstein--Yang--Mills--Born--Infeld--dilaton black string: the massive Klein--Gordon equation was solved, exactly. Next…
We consider the absorption of higher angular momentum modes of scalars into black holes, at low energies, and ask if the resulting cross sections are reproduced by a D-brane model. To get the correct dependence on the volume of the…
We study how coincident Dirichlet 3-branes absorb incident gravitons polarized along their world volume. We show that the absorption cross-section is determined by the central term in the correlator of two stress-energy tensors. The…
We study the collision of a highly energetic light closed string off a stack of Dp-branes at (sub)string-scale impact parameters and in a regime justifying a perturbative treatment. Unlike at larger impact parameters - where elastic…
We study the wave equation for a minimally coupled massive scalar in three-dimensional de Sitter space. We compute the absorption cross section to investigate its cosmological horizon in the southern diamond. Although the absorption cross…
Microscopic quantum theory of nonlinear stimulated scattering of 2D Dirac particles in doped graphene on Coulomb field of impurity ions at the presence of an external strong coherent electromagnetic radiation is developed. We consider high…
"Brane supersymmetry breaking" occurs in String Theory when the only available combinations of D-branes and orientifolds are not mutually BPS and yet do not introduce tree-level tachyon instabilities. It is characterized by the emergence of…
The evaluation of the absorption coefficients are important for particle emission caused by Hawking radiation. In the case of cosmological particle emission from the event horizon in De Sitter space, it is known that the scalar wave…
An analysis of the astrophysical $S$ factor of the proton-proton weak capture ($\mathrm{p}+\mathrm{p}\rightarrow {}^2\mathrm{H}+\mathrm{e}^++\nu_{\mathrm{e}}$) is performed on a large energy range covering solar-core and early Universe…
It is known that weak coupling calculations of absorption or emission by slightly non-extremal D-brane configurations are in exact agreement with semiclassical results for the black holes they describe at strong couplings. We investigate…
The microscopic quantum theory of nonlinear stimulated scattering of chiral particles in doped $AB$ stacked bilayer graphene on Coulomb field of charged impurities in the presence of strong coherent electromagnetic radiation is presented.…