322 research outputs found
On ADE Quiver Models and F-Theory Compactification
Based on mirror symmetry, we discuss geometric engineering of N=1 ADE quiver
models from F-theory compactifications on elliptic K3 surfaces fibered over
certain four-dimensional base spaces. The latter are constructed as
intersecting 4-cycles according to ADE Dynkin diagrams, thereby mimicking the
construction of Calabi-Yau threefolds used in geometric engineering in type II
superstring theory. Matter is incorporated by considering D7-branes wrapping
these 4-cycles. Using a geometric procedure referred to as folding, we discuss
how the corresponding physics can be converted into a scenario with D5-branes
wrapping 2-cycles of ALE spaces.Comment: 21 pages, Latex, minor change
Mirror Symmetry and Landau Ginzburg Calabi-Yau Superpotentials in F-theory Compactifications
We study Landau Ginzburg (LG) theories mirror to 2D N=2 gauged linear sigma
models on toric Calabi-Yau manifolds. We derive and solve new constraint
equations for Landau Ginzburg elliptic Calabi-Yau superpotentials, depending on
the physical data of dual linear sigma models. In Calabi-Yau threefolds case,
we consider two examples. First, we give the mirror symmetry of the canonical
line bundle over the Hirzebruch surfaces . Second, we find a special
geometry with the affine so(8) Lie algebra toric data extending the geometry of
elliptically fibered K3. This geometry leads to a pure N=1 six dimensional
SO(8) gauge model from the F-theory compactification. For Calabi-Yau fourfolds,
we give a new algebraic realization for ADE hypersurfaces.Comment: 27 pages, latex. To appear in Journal of Physics A: Mathematical and
Genera
On Thermodynamics of AdS Black Holes in M-Theory
Motivated by a recent work on asymptotically AdS_4 black holes in M-theory,
we investigate the thermodynamics and thermodynamical geometry of AdS black
holes from M2 and M5-branes. Concretely, we consider AdS black holes in
AdS_{p+2}\times S^{11-p-2}, where p=2,5 by interpreting the number of M2 (and
M5-branes) as a thermodynamical variable. We study the corresponding phase
transition to examine their stabilities by calculating and discussing various
thermodynamical quantities including the chemical potential. Then, we compute
the thermodynamical curvatures from the Quevedo metric for M2 and M5-branes
geometries to reconsider the stability of such black objects. The Quevedo
metric singularities recover similar stability results provided by the phase
transition program.Comment: 16 pages, 12 figures. Late
Ehrenfest Scheme of Higher Dimensional Topological AdS Black Holes in The Third Order Lovelock-Born-Infeld Gravity
Interpreting the cosmological constant as a thermodynamic pressure and its
conjugate quantity as a thermodynamic volume, we reconsider the investigation
of P-V critical behaviors of (1+n)-dimensional topological AdS black holes in
Lovelock-Born-Infeld gravity. In particular, we give an explicit expression of
the universal number \chi=\frac{P_c v_c}{T_c} in terms of the space dimension
. Then, we examine the phase transitions at the critical points of such
topological black holes for 6 \leq n \leq 11 as required by the physical
condition of the thermodynamical quantities. More precisely, the Ehrenfest
equations have been checked revealing that the black hole system undergoes a
second phase transition at the critical points.Comment: 18 pages, latex with 10 figures, titled modified, section added,
typos corrected, accepted for publication in International Journal of
Geometric Methods in Modern Physics (2015
Maxwell's equal-area law for Gauss-Bonnet Anti-de Sitter black holes
Interpreting the cosmological constant \Lambda as a thermodynamic pressure
and its conjugate quantity as a thermodynamic volume, we study the Maxwell's
equal area law of higher dimensional Gauss-Bonnet-AdS black holes in extended
phase space. These black hole solutions critically behave like Van der Waals
systems. It has been realized that below the critical temperature T_c the
stable equilibrium is violated. We show through calculations that the critical
behaviors for the uncharged black holes only appear in d=5. For the charged
case, we analyse solutions in d = 5 and d = 6 separately and find that, up to
some constrains, the critical behaviors only appear in the spherical topology.
Using the Maxwell's construction, we also find the isobar line for which the
liquid-gas-like phases coexist.Comment: 18 pages, 4 figures, latex. References added and typos corrected.
Minor changes. Final version accepted in European Physical Journal
On Heat Properties of AdS Black Holes in Higher Dimensions
We investigate the heat properties of AdS Black Holes in higher dimensions.
We consider the study of the corresponding thermodynamical properties including
the heat capacity explored in the determination of the black hole stability. In
particular, we compute the heat latent. To overcome the instability problem,
the Maxwell construction, in the (T,S)-plane, is elaborated. This method is
used to modify the the Hawking-Page phase structure by removing the negative
heat capacity regions. Then, we discuss the thermodynamic cycle and the heat
engines using the way based on the extraction of the work from a black hole
solution.Comment: 15 pages, 16 figures. latex. Minor modifications, version has been
accepted in JHEP, 201
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