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In this article, we investigate the thermal properties of non-relativistic many-body systems at finite temperatures and chemical potential. We compute the one-point function of various operators constructed out of the basic fields in ideal bosonic and fermionic many-body systems. The one-point function is non-zero only for operators with zero particle numbers. We investigate these operators in R d and R + d , i.e. a flat space with a planar boundary. Furthermore, we compute the Green’s function and using the operator product expansion, we express it in terms of the thermal one-point function of the higher spin currents. On R + d , the operator product expansion allows to express the bulk-bulk Green’s function in terms of the thermal Green’s function of the boundary operators. We also study the ideal system by placing it on curved spatial surfaces, specifically spherical surfaces. We compute the partition function and Green’s function on spheres, squashed-sphere and hemispheres. Finally, we compute the large radius corrections to the partition function and Green’s function by expanding in the large radius limit.

Non-relativistic conformal field theory describes many-body physics at unitarity. The correlation functions of the system are fixed by the requirement of the conformal invariance. In this article, we discuss the correlation functions of scalar operators in non-relativistic conformal field theories in momentum space. We discuss the solution of conformal Ward identities and express 2,3, and 4-point functions as a function of energy and momentum. We also express the 3- and 4-point functions as the one-loop and three-loop Feynman diagram computations in the momentum space. Lastly, we generalize the discussion to the momentum space correlation functions in the presence of a boundary.

A bstract Non-relativistic conformal field theory is significant to understand various aspects of an ultra-cold system. In this paper, we study a non-relativistic system of two-component fermions interacting with a complex boson with Yukawa-like interactions near d = 4-spatial dimensions in the presence of a quenched disorder. The homogeneous theory flows to an interacting fixed point describing a unitary fermion system. In the presence of the disorder, we find that the system has an interesting phase structure in the space of the coupling constants and exhibits an interacting disorder fixed point in ϵ -expansion. The correlation function obeys Lifshitz scaling behaviour at the disorder fixed point with the anisotropic exponent being z = 2 + γ E . We also study the disorder system at finite temperature and compute the leading contribution to the 1PI effective action.

AdS 2 / CFT 1 correspondence leads to a prescription for computing the degeneracy of black hole states in terms of path integral over string fields living on the near horizon geometry of the black hole. In this paper we make use of the enhanced supersymmetries of the near horizon geometry and localization techniques to argue that the path integral receives contribution only from a special class of string field configurations which are invariant under a subgroup of the supersymmetry transformations. We identify saddle points which are invariant under this subgroup. We also use our analysis to show that the integration over infinite number of zero modes generated by the asymptotic symmetries of AdS 2 generate a finite contribution to the path integral.

A bstract We study non-relativistic conformal field theory on a flat space in the presence of a planar boundary. We compute correlation functions of primary operators and obtain the expression for the boundary conformal block. We also discuss the non-relativistic conformal field theory on a general curved background in the presence of a boundary. As an example, we discuss the spectrum of boundary primary operator and compute scaling dimensions in a fermionic theory near one and three spatial dimensions.

A bstract We present a formula for the quantum entropy of supersymmetric five-dimensional spinning black holes in M-theory compactified on CY 3 , i.e., BMPV black holes. We use supersymmetric localization in the framework of off-shell five dimensional N = 2 supergravity coupled to I = 1, . . . , N V + 1 off-shell vector multiplets. The theory is governed at two-derivative level by the symmetric tensor C IJK (the intersection numbers of the Calabi-Yau) and at four-derivative level by the gauge-gravitational Chern-Simons coupling c I (the second Chern class of the Calabi-Yau). The quantum entropy is an N V +2-dimensional integral parameterised by one real parameter φ I for each vector multiplet and an additional parameter φ 0 for the gravity multiplet. The integrand consists of an action governed completely by C IJK and c I , and a one-loop determinant. Consistency with the on-shell logarithmic corrections to the entropy, the symmetries of the very special geometry of the moduli space, and an assumption of analyticity constrains the one-loop determinant up to a scale-independent function g ( φ 0 ). For g = 1 our result agrees completely with the topological M-theory conjecture of Dijkgraaf, Gukov, Neitzke, and Vafa for static black holes at two derivative level, and provides a natural extension to higher derivative corrections. For rotating BMPV black holes, our result differs from the DGNV conjecture at the level of the first quantum corrections.

A bstract We use localization to compute the partition function of a four dimensional, supersymmetric, abelian gauge theory on a hemisphere coupled to charged matter on the boundary. Our theory has eight real supercharges in the bulk of which four are broken by the presence of the boundary. The main result is that the partition function is identical to that of N = 2 abelian Chern-Simons theory on a three-sphere coupled to chiral multiplets, but where the quantized Chern-Simons level is replaced by an arbitrary complexified gauge coupling τ . The localization reduces the path integral to a single ordinary integral over a real variable. This integral in turn allows us to calculate the scaling dimensions of certain protected operators and two-point functions of abelian symmetry currents at arbitrary values of τ . Because the underlying theory has conformal symmetry, the current two-point functions tell us the zero temperature conductivity of the Lorentzian versions of these theories at any value of the coupling. We comment on S-dualities which relate different theories of supersymmetric graphene. We identify a couple of self-dual theories for which the complexified conductivity associated to the U(1) gauge symmetry is τ /2.

Abstract The partition functions of free bosons as well as fermions on AdS 2 are not smooth as a function of their masses. For free bosons, the partition function on AdS 2 is not smooth when the mass saturates the Breitenlohner-Freedman bound. We show that the expectation value of the scalar bilinear on AdS 2 exhibits a kink at the BF bound and the change in slope of the expectation value with respect to the mass is proportional to the inverse radius of AdS 2. For free fermions, when the mass vanishes the partition function exhibits a kink. We show that expectation value of the fermion bilinear is discontinuous and the jump in the expectation value is proportional to the inverse radius of AdS 2. We then show the supersymmetric actions of the chiral multiplet on AdS 2 × S 1 and the hypermultiplet on AdS 2 × S 2 demonstrate these features. The supersymmetric backgrounds are such that as the ratio of the radius of AdS 2 to S 1 or S 2 is dialled, the partition functions as well as expectation of bilinears are not smooth for each Kaluza-Klein mode on S 1 or S 2. Our observation is relevant for evaluating one-loop partition function in the near horizon geometry of extremal black holes.

A bstract We compute the partition function of N = 2 supersymmetric mixed dimensional QED on a squashed hemisphere using localization. Mixed dimensional QED is an abelian gauge theory coupled to charged matter fields at the boundary. The partition function is a function of the complex gauge coupling τ , the choice of R-symmetry and the squashing deformation. The superconformal R-symmetry is determined using the 3-dimensional F-maximization. The free energy as a function of squashing deformation allows computing correlation functions that contain the insertion of the energy-momentum tensor. We compute the 2-point correlation function of the energy-momentum tensor of 3-dimensional theory by differentiating the free energy with respect to the squashing parameter. We comment on the behaviour of the 2-point function as we change the complex coupling τ .

A bstract We study the role of boundary conditions on the one loop partition function the N = 2 chiral multiplet of R-charge Δ on AdS 2 × S 1 . The chiral multiplet is coupled to a background vector multiplet which preserves supersymmetry. We implement normalizable boundary conditions in AdS 2 and develop the Green’s function method to obtain the one loop determinant. We evaluate the one loop determinant for two different actions: the standard action and the Q -exact deformed positive definite action used for localization. We show that if there exists an integer n in the interval D : Δ − 1 2 L Δ 2 L , where L being the ratio of radius of AdS 2 to that of S 1 , then the one loop determinants obtained for the two actions differ. It is in this situation that fields which obey normalizable boundary conditions do not obey supersymmetric boundary conditions. However if there are no integers in D , then fields which obey normalizable boundary conditions also obey supersymmetric boundary conditions and the one loop determinants of the two actions precisely agree. We also show that it is only in the latter situation that the one loop determinant obtained by evaluating the index of the D 10 operator associated with the localizing action agrees with the one loop determinant obtained using Green’s function method.