33 research outputs found
Logarithmic Corrections to Entropy of Magnetically Charged AdS4 Black Holes
We compute logarithmic corrections to the entropy of a magnetically charged
extremal black hole in AdS4 x S7 using the quantum entropy function and discuss
the possibility of matching against recently derived microscopic expressions.Comment: 14 page
Twisting and localization in supergravity: equivariant cohomology of BPS black holes
We develop the formalism of supersymmetric localization in supergravity using
the deformed BRST algebra defined in the presence of a supersymmetric
background as recently formulated in arxiv:1806.03690. The gravitational
functional integral localizes onto the cohomology of a global supercharge
, obeying , where is a global symmetry of the
background. Our construction naturally produces a twisted version of
supergravity whenever supersymmetry can be realized off-shell. We present the
details of the twisted graviton multiplet and ghost fields for the
superconformal formulation of four-dimensional N=2 supergravity. As an
application of our formalism, we systematize the computation of the exact
quantum entropy of supersymmetric black holes. In particular, we compute the
one-loop determinant of the deformation operator for
the off-shell fluctuations of the Weyl multiplet around the
saddle. This result, which is consistent with the corresponding large-charge
on-shell analysis, is needed to complete the first-principles computation of
the quantum entropy.Comment: V2: subsection 4.3 added, typo corrected, accepted version in JHEP;
V3: typos correcte
Supersymmetric Double Field Theory: Stringy Reformulation of Supergravity
We construct a supersymmetric extension of double field theory that realizes
the ten-dimensional Majorana-Weyl local supersymmetry. In terms of a stringy
differential geometry we proposed earlier, our action consists of five simple
terms -- two bosonic plus three fermionic -- and manifests not only
diffeomorphism and one-form gauge symmetry of B-field, but also O(10,10)
T-duality as well as a direct product of two local Lorentz symmetries, SO(1,9)
\times SO(9,1). A gauge fixing that identifies the double local Lorentz groups
reduces our action to the minimal supergravity in ten dimensions.Comment: Initally submitted to PRL on 28th November 2011. 5+4 pages (Five
pages of publication in PRD Rapid Communications plus Four pages of
Appendix). v4) Typo in Eq.(34) fixed, Erratum to be published in journal. cf.
http://www.newton.ac.uk/programmes/BSM/seminars/021611301.htm
Supersymmetric Localization for BPS Black Hole Entropy: 1-loop Partition Function from Vector Multiplets
We use the techniques of supersymmetric localization to compute the BPS black
hole entropy in N=2 supergravity. We focus on the n_v+1 vector multiplets on
the black hole near horizon background which is AdS_2 x S^2 space. We find the
localizing saddle point of the vector multiplets by solving the localization
equations, and compute the exact one loop partition function on the saddle
point. Furthermore, we propose the appropriate functional integration measure.
Through this measure, the one loop determinant is written in terms of the
radius of the physical metric, which depends on the localizing saddle point
value of the vector multiplets. The result for the one loop determinant is
consistent with the logarithmic corrections to the BPS black hole entropy from
vector multiplets.Comment: 28+16 pages, improved discussion on the boundary mode in the 4.2 and
conclusion sectio
Periodic Arrays of M2-Branes
We consider periodic arrays of M2-branes in the ABJM model in the spirit of a
circle compactification to D2-branes in type IIA string theory. The result is a
curious formulation of three-dimensional maximally supersymmetric Yang-Mills
theory in terms of fermions, seven transverse scalars, a non-dynamical gauge
field and an additional scalar `dual gluon'. Upon further T-duality on a
transverse torus we obtain a non-manifest-Lorentz-invariant description of
five-dimensional maximally supersymmetric Yang-Mills. Here the additional
scalar field can be thought of as the components of a two-form along the torus.
This action can be viewed as an M-theory description of M5-branes on .Comment: 20 pages, 1 figure, v3: typos corrected, published versio
Stringy Unification of Type IIA and IIB Supergravities under N=2 D=10 Supersymmetric Double Field Theory
To the full order in fermions, we construct D=10 type II supersymmetric
double field theory. We spell the precise N=2 supersymmetry transformation
rules as for 32 supercharges. The constructed action unifies type IIA and IIB
supergravities in a manifestly covariant manner with respect to O(10,10)
T-duality and a pair of local Lorentz groups, or Spin(1,9) \times Spin(9,1),
besides the usual general covariance of supergravities or the generalized
diffeomorphism. While the theory is unique, the solutions are twofold. Type IIA
and IIB supergravities are identified as two different types of solutions
rather than two different theories.Comment: v1) 4+9 pages. v2) 1+26 pages, Unification highlighted. References
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Supersymmetric gauged Double Field Theory: Systematic derivation by virtue of \textit{Twist}
In a completely systematic and geometric way, we derive maximal and
half-maximal supersymmetric gauged double field theories in lower than ten
dimensions. To this end, we apply a simple twisting ansatz to the
ungauged maximal and half-maximal supersymmetric double field theories
constructed previously within the so-called semi-covariant formalism. The
twisting ansatz may not satisfy the section condition. Nonetheless, all the
features of the semi-covariant formalism, including its complete
covariantizability, are still valid after the twist under alternative
consistency conditions. The twist allows gaugings as supersymmetry preserving
deformations of the untwisted theories after Scherk-Schwarz-type
dimensional reductions. The maximal supersymmetric twist requires an extra
condition to ensure both the Ramond-Ramond gauge symmetry and the
supersymmetries unbroken.Comment: 1+58 pages, section 4 enhanced, refs added. To appear in JHE
Supersymmetry and complexified spectrum on Euclidean AdS
Quantum study of supersymmetric theories on Euclidean two dimensional anti-de
Sitter space (AdS) is invalid if we use the standard normalizable
functional basis due to its incompatibility with supersymmetry. We cure this
problem by demonstrating that supersymmetry requires complexified spectrum and
constructing the supersymmetric basis for scalar and spinor fields. Our new
basis is free of fermionic zero modes, delta-function normalizable with respect
to a newly defined inner product, and compatible with the supersymmetric
asymptotic boundary condition. We also explore the 1-loop evaluation using this
basis and show that it agrees with the standard non-supersymmetric basis up to
a global contribution arising from the fermion zero mode.Comment: 6 pages, no figure; v2 modified abstract and some clarifications
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