1,721,046 research outputs found
The Kontsevich connection on the moduli space of FZZT Liouville branes
No full textWe point out that insertions of matrix fields in (connected amputated) amplitudes of (generalized) Kontsevich models are given by covariant derivatives with respect to the Kontsevich moduli. This implies that correlators are sections of symmetric products of the (holomorphic) tangent bundle on the (complexified) moduli space of FZZT Liouville branes. We discuss the relation of Kontsevich parametrization of moduli space with that provided by either the (p, 1) or the (1, p) boundary con- formal field theories. It turns out that the Kontsevich connection captures the contribution of contact terms to open string amplitudes of boundary cosmological constant operators in the (1, p) minimal string models. The curvature of the connection is of type (1, 1) and has delta-function singularities at the points in moduli space where Kontsevich kinetic term vanishes. We also outline the extention of our formalism to the c = 1 string at self-dual radius and discuss the problems that have to be understood to reconciliate first and second quantized approaches in this case
The Kontsevich connection on the moduli space of FZZT Liouville branes
No full textWe point out that insertions of matrix fields in (connected amputated) amplitudes of (generalized) Kontsevich models are given by covariant derivatives with respect to the Kontsevich moduli. This implies that correlators are sections of symmetric products of the (holomorphic) tangent bundle on the (complexified) moduli space of FZZT Liouville branes. We discuss the relation of Kontsevich parametrization of moduli space with that provided by either the (p,1) or the (1,p) boundary conformal field theories. It turns out that the Kontsevich connection captures the contribution of contact terms to open string amplitudes of boundary cosmological constant operators in the (1,p) minimal string models. The curvature of the connection is of type (1,1) and has delta-function singularities at the points in moduli space where Kontsevich kinetic term vanishes. We also outline the extention of our formalism to the c=1 string at self-dual radius and discuss the problems that have to be understood to reconciliate first and second quantized approaches in this case
Stationary axisymmetric solutions of five dimensional gravity,
No full textWe consider stationary axisymmetric solutions of general relativity that asymptote to five dimensional Minkowski space. It is known that this system has a hidden SL(3,R) symmetry. We identify an SO(2,1) subgroup of this symmetry group that preserves the asymptotic boundary conditions. We show that the action of this subgroup on a static solution generates a one-parameter family of stationary solutions carrying angular momentum. We conjecture that by repeated applications of this procedure one can generate all stationary axisymmetric solutions starting from static ones. As an example, we derive the Myers-Perry black hole starting from the Schwarzschild solution in five dimensions
Physical states at the tachyonic vacuum of open string field theory
No full textWe illustrate a method for computing the number of physical states of open string theory at the stable tachyonic vacuum in level truncation approximation. The method is based on the analysis of the gauge-fixed open string field theory quadratic action that includes Fadeev-Popov ghost string fields. Computations up to level 9 in the scalar sector are consistent with Sen's conjecture about the absence of physical open string states at the tachyonic vacuum. We also derive a long exact cohomology sequence that relates relative and absolute cohomologies of the BRS operator at the non-perturbative vacuum. We use this exact result in conjunction with our numerical findings to conclude that the higher ghost number non-perturbative BRS cohomologies are non-empty
Physical states at the tachyonic vacuum of open string field theory
No full textWe illustrate a method for computing the number of physical states of open string theory at the stable tachyonic vacuum in level truncation approximation. The method is based on the analysis of the gauge-fixed open string field theory quadratic action that includes Fadeev–Popov ghost string fields. Computations up to level 9 in the scalar sector are consistent with Sen’s conjecture about the absence of physical open string states at the tachyonic vacuum. We also derive a long exact cohomology sequence that relates relative and absolute cohomologies of the BRS operator at the non-perturbative vacuum. We use this exact result in conjunction with our numerical findings to conclude that the higher ghost number non-perturbative BRS cohomologies are non-empty
Fuzzball geometries and higher derivative corrections for extremal holes
No full text2-charge D1-D5 microstates are described by geometries which end in `caps' near r=0; these caps reflect infalling quanta back in finite time. We estimate the travel time for 3-charge geometries in 4-D, and find agreement with the dual CFT. This agreement supports a picture of `caps' for 3-charge geometries. We argue that higher derivative corrections to such geometries arise from string winding modes. We then observe that the `capped' geometries have no noncontractible circles, so these corrections remain bounded everywhere and cannot create a horizon or singularity
Geometry of D1-D5-P bound states
Full text linkSupersymmetric solutions of 6-d supergravity (with two translation symmetries) can be written as a hyperkahler base times a 2-D fiber. The subset of these solutions which correspond to true bound states of D1-D5-P charges give microstates of the 3-charge extremal black hole. To understand the characteristics shared by the bound states we decompose known bound state geometries into base-fiber form. The axial symmetry of the solutions make the base Gibbons-Hawking. We find the base to be actually `pseudo-hyperkahler': The signature changes from (4,0) to (0,4) across a hypersurface. 2-charge D1-D5 geometries are characterized by a `central curve' ; the analogue for 3-charge appears to be a hypersurface that for our metrics is an orbifold of
AdS3 holography for 1/4 and 1/8 BPS geometries
Full text linkThis article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credited.This research is partially supported by STFC (Grant ST/L000415/1, String theory, gauge theory & duality), by the Padova University Project CPDA119349 and by INFN
Hamiltonian formulation of open WZW strings
No full textUsing a Hamiltonian approach, we construct the classical and quantum theory of open WZW strings on a strip. (These are the strings which end on WZW branes.) The development involves non-abelian generalized Dirichlet images in an essential way. At the classical level, we find a new non-commutative geometry in which the equal-time coordinate brackets are non-zero at the world-sheet boundary, and the result is an intrinsically non-abelian effect which vanishes in the abelian limit. Using the classical theory as a guide to the quantum theory, we also find the operator algebra and the analogue of the Knizhnik-Zamolodchikov equations for the the conformal field theory of open WZW strings
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