Maximally N\cal{N}-extended super-BMS3_3 algebras and Generalized 3D Gravity Solutions

We consider the maximal $\cal{N}-$extended supergravity theory in 3 dimensions with fermionic generators transforming under real but non necessarily irreducible representations of the internal algebra. We obtain the symmetry algebra at null infinity preserving boundary conditions of asymptotically flat solutions, i.e. the maximal $\cal{N}-$extended super-BMS$_3$ algebra, which possesses non-linear correction in the anti-commutators of supercharges. We present the supersymmetric energy bound and derive the explicit form of the asymptotic Killing spinors. We also find the most generic circular symmetric ground state of the theory, which corresponds to a non-supersymmetric cosmological solutions and derive their entropy.Comment: 29+1 pages, typos correcte

Entropy of Flat Space Cosmologies from Celestial dual

We construct a one-dimensional dual theory that effectively describes the sector of the (2+1)D flat gravity phase space near a Flat Space Cosmology (FSC) saddle labeled by definite mass and angular momentum. This Schwarzian type action describes the dynamics of the (Pseudo-) Goldstone Bosons of BMS$_3$ algebra on a circle as the symmetry is spontaneously and anomalously broken. This 1D theory, living on the celestial circle, provides an explicit construction of a celestial dual in (2+1)D. We use it to calculate the semiclassical entropy of Flat Space Cosmologies and find perfect agreement with existing literature.Comment: Typos correcte

The Indian Stock Market and the Great Recession

This study analyzes the impact of the outbreak of the Great Recession of 2007 on the behavior of the Indian stock market. The SENSEX index of the Bombay Stock Exchange is analyzed for the prerecession period of January 2002 – November 2007 and the postrecession outbreak period of December 2007 – July 2010. Substantial increase in SENSEX return volatility observed during the post-recession outbreak period, whereas no substantial difference in returns between two periods is found. Also strong co-movements in returns and volatility are observed between the SENSEX and other major stock indexes during the post-recession period. Our results establish the dominance of global factors in influencing Indian stock market behavior during periods of economic turmoil

JT gravity from holographic reduction of 3D asymptotically flat spacetime

We attempt to understand the CFT$_1$ structure underlying (2+1)D gravity in flat spacetime via dimensional reduction. We observe that under superrotation, the hyperbolic (and dS$_2$) slices of flat spacetime transform to asymptotically (A)dS$_2$ slices. We consider a wedge region bounded by two such surfaces as End-of-the-World branes and employ Wedge holography to perform holographic reduction. We show that once we consider fluctuating branes, the localised theory on the branes is Jackiw-Teitelboim (JT) theory. Finally, using the dual description of JT, we derive an 1D Schwarzian theory at the spatial slice of null infinity. In this dual Celestial (nearly) CFT, the superrotation mode of 3D plays the role of the Schwarzian derivative of the boundary time reparametrization mode.Comment: 19 pages, 3 figure