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Jhingan, S

Publications and source records attributed to Jhingan, S.

Quasispherical gravitational collapse in 5D Einstein-Gauss-Bonnet gravity

We obtain a general five-dimensional quasispherical collapsing solutions of irrotational dust in Einstein gravity with the Gauss-Bonnet combination of quadratic curvature terms. These solutions are a generalization, to Einstein-Gauss-Bonnet gravity, of the five-dimensional quasispherical Szkeres like collapsing solutions in general relativity. It is found that the collapse proceeds in the same way as in the analogous spherical collapse, i.e., there exists regular initial data such that the collapse proceed to form naked singularities violating cosmic censorship conjecture. The effect of Gauss-Bonnet quadratic curvature terms on the formation and locations of the apparent horizon is deduced.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Bipolar harmonic encoding of CMB correlation patterns

Deviations from statistical isotropy can be modeled in various ways, for instance, anisotropic cosmological models (Bianchi models), compact topologies, and presence of primordial magnetic field. Signature of anisotropy manifests itself in cosmic microwave background correlation patterns. Here we explore the symmetries of the correlation function and its implications on the observable measures constructed within the bipolar harmonic formalism for these variety of models. Different quantifiers within the bipolar harmonic representation are used to distinguish between plausible models of breakdown of statistical isotropy and as a spectroscopic tool for discriminating between distinct cosmic topology.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗