arXiv subjects

Abhinava Bhattacharjee

Publications and source records attributed to Abhinava Bhattacharjee.

3 recordsLinked to original sources

arXiv2026

Supersymmetry and Attractors in N = 4 Supergravity: The Superconformal Approach

In this paper, we study the attractor mechanism for extremal, spherically symmetric black holes in pure, untruncated, N=4 Poincaré supergravity, which we demonstrate numerically. We further study the supersymmetries preserved by these attractor solutions by focussing specifically on the constant moduli solutions and show that they always preserve 1/4$^{th}$ of the total supersymmetries. We also give an argument that even the attractor solutions with a ``non-constant'' moduli would preserve 1/4$^{th}$ of the total supersymmetries. This would mean that in pure N=4 supergravity there exist no attractor solutions which are non-supersymmetric although they could in-principle exist in a matter coupled theory. We use the framework of conformal supergravity in our analysis, which is a manifestly off-shell framework and considerably simplifies the Killing spinor analysis.

hep-th↗

arXiv2026

Only Flat Spacetime is Full BPS in Four Dimensional N=3 and N=4 Supergravity

We investigate the fully supersymmetric solutions in a class of N=3 and N=4 higher derivative Poincaré supergravity theories. These class of theories are obtained within the framework of conformal supergravity using the standard Weyl multiplet and contains a set of terms related to the Weyl square term by supersymmetry. We work in the superconformal formalism and show that flat spacetime is the only fully supersymmetric solution in these theories. However, in N=2 Poincaré supergravity theories that falls into the same class, two fully supersymmetric stationary solutions exist: Bertotti-Robinson geometry ($AdS_2\times S^2$) and flat spacetime, which are known in the literature. We discuss the reason behind the richer vacua in N=2 supergravity compared to its N=3 and N=4 cousins.

hep-th↗

arXiv2026

BPS Solutions of 4d Euclidean N=2 Supergravity with Higher Derivative Interactions

We study fully BPS and a broad class of half-BPS stationary configurations of four-dimensional Euclidean N=2 supergravity with higher-derivative interactions. Working within the off-shell conformal supergravity framework of de Wit and Reys (arXiv:1706.04973), we analyse the complete set of Killing spinor equations and obtain the corresponding algebraic and differential constraints. We further derive the Euclidean attractor equations and evaluate the Wald entropy for the fully BPS AdS_2 x S^2 background. For half-BPS stationary configurations, we obtain the generalized stabilization equations expressing all fields in terms of harmonic functions on three-dimensional flat base space, extending the Lorentzian analysis of Cardoso et al (arXiv:hep-th/0009234) to the Euclidean signature. Our results provide a framework for studying supersymmetric saddles and computing the gravitational indices entirely within Euclidean higher-derivative supergravity, without recourse to analytic continuation.

hep-th↗