arXiv subjects

Mustafa Sarisaman

Publications and source records attributed to Mustafa Sarisaman.

25 records · Page 2Linked to original sources

arXiv2012

Euclidean Pseudoduality and Boundary Conditions in Sigma Models

We discuss pseudoduality transformations in two dimensional conformally invariant classical sigma models, and extend our analysis to a given boundaries of world-sheet, which gives rise to an appropriate framework for the discussion of the pseudoduality between D-branes. We perform analysis using the Euclidean spacetime and show that structures on the target space can be transformed into pseudodual manifold identically. This map requires that torsions and curvatures related to individual spaces are the same when connections are riemannian. Boundary pseudoduality imposes locality condition.

hep-th↗

arXiv2012

Optical Spectral Singularities and Coherent Perfect Absorption in a Two-Layer Spherical Medium

An optical spectral singularity is a zero-width resonance that corresponds to lasing at threshold gain. Its time-reversal causes coherent perfect absorption of light and forms the theoretical basis of antilasing. In this article we explore optical spectral singularities of a two-layer spherical medium. In particular, we examine the cases that a gain medium is coated by a thin layer of high-refractive index glass and a spherical glass covered by a layer of gain material. In the former case, the coating reduces the minimum radius required for exciting spectral singularities and gives rise to the formation of clusters of spectral singularities separated by wide spectral gaps. In the latter case, the coating leads to a doubling of the number of spectral singularities.

physics.optics↗

arXiv2011

Spectral Singularities of a Complex Spherical Barrier Potential and Their Optical Realization

The mathematical notion of a spectral singularity admits a physical interpretation as a zero-width resonance. It finds an optical realization as a certain type of lasing effect that occurs at the threshold gain. We explore spectral singularities of a complex spherical barrier potential and study their realization as transverse spherical electromagnetic waves emitted by a gain medium with a spherical geometry. In particular, for a typical dye laser material, we obtain a lower bound on the size of the gain medium for the occurence of this kind of spectral singularities.

math-ph↗

arXiv2009

Pseudoduality Between Symmetric Space Sigma Models

We study the pseudoduality transformation on the symmetric space sigma models. We switch the Lie group valued pseudoduality equations to Lie algebra valued ones, which leads to an infinite number of pseudoduality equations. We obtain an infinite number of conserved currents on the tangent bundle of the pseudodual manifold. We show that there can be mixing of decomposed spaces with each other, which leads to mixings of the following expressions. We obtain the mixing forms of curvature relations and one loop renormalization group beta functions by means of these currents.

hep-th↗

arXiv2009

Pseudoduality in Supersymmetric Sigma Models on Symmetric Spaces

We discuss the target space pseudoduality in supersymmetric sigma models on symmetric spaces using two different methods, orthonormal coframe and component expansion. These two methods yield similar results to the classical cases with the exception that commuting bracket relations in classical case turns out to be anticommuting ones because of the appearance of grassmann numbers. In component expansion method it is understood that constraint relations in case of non-mixing pseudoduality are the remnants of mixing pseudoduality. Once mixing terms are included in the pseudoduality relations the constraint relations disappear.

hep-th↗

arXiv2009

Pseudoduality in Supersymmetric Sigma Models

We study the pseudoduality transformation in supersymmetric sigma models. We generalize the classical construction of pseudoduality transformation to supersymmetric case. We perform this both by component expansion method on manifold M and by orthonormal coframe method on manifold SO(M). The component expansion method yields the result that pseudoduality tranformation is not invertible at all points and occurs from all points on one manifold to only one point where riemann normal coordinates are valid on the second manifold. Torsion of the sigma model on M must vanish while it is nonvanishing on pseudodual manifold, and curvatures of the manifolds must be constant and the same. In case of super WZW sigma models pseudoduality equations result in three different pseudoduality conditions; flat space, chiral and antichiral pseudoduality.

hep-th↗

arXiv2009

Pseudoduality and Conserved Currents in Sigma Models

We discuss the current conservation laws in sigma models based on a compact Lie groups of the same dimensionality and connected to each other via pseudoduality transformations in two dimensions. We show that pseudoduality transformations induce an infinite number of nonlocal conserved currents on the pseudodual manifold.

hep-th↗