Superconformal Quantum Mechanics Research Articles

Black hole entropy, marginal stability and mirror symmetry

We consider the superconformal quantum mechanics associated to BPS black holes in type IIB Calabi-Yau compactifications. This quantum mechanics describes the dynamics of D-branes in the near-horizon attractor geometry of the black hole. In many cases, the black hole entropy can be found by counting the number of chiral primaries in this quantum mechanics. Both the attractor mechanism and notions of marginal stability play important roles in generating the large number of microstates required to explain this entropy. We compute the microscopic entropy explicitly in a few different cases, where the theory reduces to quantum mechanics on the moduli space of special Lagrangians. Under certain assumptions, the problem may be solved by implementing mirror symmetry as three T-dualities: this is essentially the mirror of a calculation by Gaiotto, Strominger and Yin. In some simple cases, the calculation may be done in greater generality without resorting to conjectures about mirror symmetry. For example, the K3 × T2 case may be studied precisely using the Fourier-Mukai transform.

Two-charge small black hole entropy: string-loops and multi-strings

We investigate the inclusion of 10-dimensional string loop corrections to the entropy function of two-charge extremal small black holes of the heterotic string theory compactified on S^1 x T^5 and show that the entropy is given by \pi\sqrt{a q_1 q_2+b q_1} where q_1 and q_2 are the charges with q_1 >> q_2 >> 1 and a and b are constants. Incorporating certain multi-string states into the microstate counting, we show that the new statistical entropy is consistent with the macroscopic scaling for one and two units of momentum (winding) and large winding (momentum). We discuss our scaling from the point of view of related AdS_3 central charge and counting of chiral primaries in superconformal quantum mechanics as well.

Comments onAdS2solutions ofD= 11 supergravity

We study the supersymmetric solutions of 11-dimensional supergravity with a factor of $AdS_2$ made of M2-branes. Such solutions can provide gravity duals of superconformal quantum mechanics, or through double Wick rotation, the generic bubbling geometry of M-theory which are 1/16-BPS. We show that, when the internal manifold is compact, it should take the form of a warped U(1)-fibration over an 8-dimensional Kahler space.

D0-branes in black hole attractors

Configurations of N probe D0-branes in a Calabi-Yau black hole are studied. A large degeneracy of near-horizon bound states are found which can be described as lowest Landau levels tiling the horizon of the black hole. These states preserve some of the enhanced supersymmetry of the near-horizon AdS_2xS^2xCY attractor geometry, but not of the full asymptotically flat solution. Supersymmetric non-abelian configurations are constructed which, via the Myers effect, develop charges associated with higher-dimensional branes wrapping CY cycles. An SU(1,1|2) superconformal quantum mechanics describing D0-branes in the attractor geometry is explicitly constructed.

Superconformal black hole quantum mechanics

In recent work, the superconformal quantum mechanics describing D0 branes in the AdS_2xS^2xCY_3 attractor geometry of a Calabi-Yau black hole with D4 brane charges p^A has been constructed and found to contain a large degeneracy of chiral primary bound states. In this paper it is shown that the asymptotic growth of chiral primaries for N D0 branes exactly matches the Bekenstein-Hawking area law for a black hole with D4 brane charge p^A and D0 brane charge N. This large degeneracy arises from D0 branes in lowest Landau levels which tile the CY_3xS^2 horizon. It is conjectured that such a multi-D0 brane CFT1 is holographically dual to IIA string theory on AdS_2xS^2xCY_3.

Superconformal quantum mechanics of small black holes

Recently, Gaiotto, Strominger and Yin have proposed a holographic dual description for the near-horizon physics of certain N=2 black holes in terms of the superconformal quantum mechanics on D0-branes in the attractor geometry. We provide further evidence for their proposal by applying it to the case of `small' black holes which have vanishing horizon area in the leading supergravity approximation. We consider 2-charge black holes in type IIA on $T^2 \times M$, where $M$ can be either $K_3$ or $T^4$, made up out of D0-branes and D4-branes wrapping $M$. We construct the corresponding superconformal quantum mechanics and show that the asymptotic growth of chiral primaries exactly matches with the known entropy of these black holes. The state-counting problem reduces to counting lowest Landau levels on $T^2$ and Dolbeault cohomology classes on $M$.

Super-Calogero model with OSp(2|2) supersymmetry: is the construction unique?

We show that the construction of super-Calogero model with OSp(2|2) supersymmetry is not unique. In particular, we find a new co-ordinate representation of the generators of the OSp(2|2) superalgebra that appears as the dynamical supersymmetry of the rational super-Calogero model. Both the quadratic and the cubic Casimir operators of the OSp(2|2) are necessarily zero in this new representation, while they are, in general, non-zero for the super-Calogero model that is currently studied in the literature. The Scasimir operator that exists in the new co-ordinate representation is not present in the case of the existing super-Calogero model. We also discuss the case of N free superoscillators and superconformal quantum mechanics for which the same conclusions are valid.

On the super-conformal quantum mechanics in the nonlinear realizations approach

In the framework of nonlinear realizations we rederive the action of the N=2 super-conformal quantum mechanics (SCQM). We propose also the WZNW-like construction of interaction term in the Lagrangian with the help of Cartan's Omega-forms.

N = 4 Superconformal Quantum Mechanics in One Dimension and Its Algebraic Structure**The project supported by National Natural Science Foundation of China (19905005), and partly by Major State Basic Research Development Programs (G2000077400 and G2000077604) and Tsinghua Natural Science Foundation (985 Program)

N = 4 superconformal quantum mechanics of nonrelativistic particles in the typical -potentials, which holds not only supersymmetry but also dynamical conformal symmetry, is studied. The corresponding superconformal quantum mechanical algebra, which contains supersymmetric quantum mechanical algebra with four supercharges and conformal algebra as subalgebras, and its two canonical group chains are established.

Invariants of topological quantum mechanics

We investigate a new topological invariant of the punctured plane using a Hamiltonian approach. The Hamiltonian is built out of topological invariants available on the punctured plane. On the other hand it is shown that the model is a generalized version, using the appropriate language of homotopy, of the superconformal quantum mechanics (gauge approach) recently proposed by L. Baulieu et al. This relationship allows a better understanding of the structure and results of the gauge approach and makes possible a proper identification of the topological invariants which emerge from it.

Representation theory of superconformal quantum mechanics

The analogy between the representations of SU(1,1/1) and SU(2,2/1) is explained and used to suggest the latter as a spectrum supergroup of superconformal relativistic quantum mechanics for systems with rotational degrees of freedom.

Superconformal quantum mechanics

N = 1 and N = 2 superconformal quantum mechanics are formulated and solved. Spontaneous symmetry breaking occurs. A de Sitter subalgebra is used to define new supersymmetric evolution operators. The modified system has a discrete spectrum exhibiting new supersymmetries. The N = 2 extended de Sitter superalgebra is spontaneously broken to N = 1. The relation to the behaviour of finite field theories and Poincaré invariance is discussed.