84 research outputs found
Type IIA on a Compact Calabi-Yau and D=11 Supergravity Uplift of its Orientifold
Using the prescription of [1] for defining period integrals in the
Landau-Ginsburg theory for compact Calabi-Yau's, we obtain the Picard-Fuchs
equation and the Meijer basis of solutions for the compact Calabi-Yau
CY_3(3,243) expressed as a degree-24 Fermat hypersurface AFTER resolution of
the orbifold singularities. This is similar in spirit to the method of
obtaining Meijer basis of solutions in [2] for the case wherein one is away
from the orbifold singularities, and one is considering the large-base limit of
the Calabi-Yau. The importance of the method lies in the ease with which one
can consider the large AND small complex structure limits, as well as the
ability to get the "ln"-terms in the periods without having to parametrically
differentiate infinite series. We consider in detail the evaluation of the
monodromy matrix in the large and small complex structure limits. We also
consider the action of the freely acting antiholomorphic involution of [2],[3]
on D=11 supergravity compactified on CY_3(3,243) x S^1 [4] and obtain the
Kaehler potential for the same in the limit of large volume of the Calabi-Yau.
As a by-product, we also give a conjecture for the action of the
orientation-reversing antiholomorphic involution on the periods, given its
action on the cohomology, using a canonical (co)homology basis. Finally, we
also consider showing a null superpotential on the orientifold of type IIA on
CY_3(3,243), having taken care of the orbifold singularities, thereby
completing the argument initiated in [2].Comment: 45 pages, LaTex, 2 ps figures; v3: (Fort. der. Physik) Journal
versio
TeV scale model for neutrino masses, dark matter and leptogenesis
We present a TeV scale model for leptogenesis where the origin of neutrino
masses are independent of the scale of leptogenesis. As a result, the model
could be extended to explain {\it dark matter, neutrino masses and leptogenesis
at the TeV scale}. The most attractive feature of this model is that it
predicts a few hundred GeV triplet Higgs scalar that can be tested at LHC or
ILC.Comment: 4 pages, contribution to International workshop on theoretical high
energy physics (IWTHEP), Roorkee, 200
On Aspects of Holographic Thermal QCD at Finite Coupling
Some Physics (obtaining lattice-compatible deconfinement temperature, some
transport coefficients and Einstein's relation) and Mathematics (torsion
classes and supersymmetry) issues pertaining to the delocalized SYZ type IIA
mirror of [1] and its M theory uplift in the MQGP limit of [2], are discussed.Comment: v3: 1+63 pages, LaTeX, title slightly modified, large amounts of
explanatory material added and text rearranged though Results are unchanged,
references added, to appear in NPB (the journal version also includes two
figs excluded in the arxiv version due to size constraints). arXiv admin
note: text overlap with arXiv:hep-th/0211102 by other author
Transport Coefficients of Black MQGP M3-Branes
The SYZ mirror, in the `delocalized limit' of [1], of (M)N
(fractional)D3-branes, and wrapped N_f flavor D7-branes in the presence of a
black-hole resulting in a non-Kaehler resolved warped deformed conifold
(NKRWDC) in [2], was carried out in [3] and resulted in black M3-branes. The
uplift, if valid globally(like [4] for fractional D3 branes in conifolds),
asymptotes to M5-branes wrapping a two-cycle (homologously an (large) integer
sum of two-spheres) in AdS_5xM_6. Interestingly, in the MQGP limit, assuming
the deformation > resolution, by estimating the five SU(3) structure torsion
(\tau) classes W_{1,2,3,4,5} we show that \tau\in W_4+W_5: 2/3
Re(W^3bar_5)=W^3bar_4 in the UV, implying the NKRWDC locally preserves SUSY.
Further, the local T^3 of [3] in the large-r limit and the `MQGP' limit of [3],
satisfies the same conditions as the maximal T^2-invariant special Lagrangian
three-cycle of T^*(S^3) of [6], partly justifying use of local SYZ mirror
symmetry in [3]. Using the Ouyang embedding in the DBI action of a D7-brane or
by dimensionally reducing the 11-dimensional EH action to five (R^{1,3},r)
dimensions, we then calculate a variety of gauge and metric-perturbation-modes'
two-point functions using the prescription of [5], and show: (i) diffusion
constant D~1/T, (ii) the electrical conductivity \sigma~T, (iii) the charge
susceptibility \chi~ T^2, (iv) [using (i) - (iii)] the Einstein's relation
\sigma/\chi=D, is indeed satisfied, (v) the R-charge diffusion constant
D_R~1/T, and (vi) the possibility of generating \eta/s=1/4pi from solutions to
the vector and tensor mode metric perturbations' EOMs, separately. All results
are also valid in the limit of [2].Comment: v4:1+50 pages, correction in torsion classes: type IIB, locally, has
SUSY in the U
Towards MQGP
For the Ouyang embedding we calculate the chemical potential mu_C due to a
U(1) gauge field on the w.v. of N_f D7-branes wrapped around a 4-cycle in a
resolved warped deformed conifold with (M)N (fractional)D3-branes of [1], and
show the possible thermodynamical stability up to linear order in the embedding
parameter. In the spirit of [2] we obtain the local type IIA mirror using SYZ
mirror symmetry near (theta_{1,2},psi)=(,{0,2pi,,4pi}) and then
oxidize the same to M theory. We take two limits of this
uplift:(i)g_s,g_sN_f,g_sM^2/N,g_s^2M N_f>1 similar to [1]
effected by M eps^{-3d/2}, N eps^{-19d},g_s epsn^d,d>0 and eps<=O(0.01);(ii)the
`MQGP limit' g_sM^2/N>1 for finite g_s,M, effected by: g_s eps, M
eps^{-3d/2},N eps^{-39d},d>0, eps<~1). The second limit is more suited for the
study of QGP (See [3]) and can only be addressed in M theory. The uplift gives
a black M3-brane solution whose near-horizon geometry near
theta_{1,2}=0,pi-branches, preserves 1/8 SUSY. We obtain eta/s=1/4pi for the
uplift and the diffusion constant for types IIB/IIA backgrounds comes out to be
~1/T, for both limits. The D=11 SUGRA action up to O(R^4,|G_4|^2) is expected
to receive dominant contributions near =0,pi due to poles.
Introducing a small-angle cut-off c and using the =c,(pi-c)-local
uplift the specific heat from the IR-finite part of the action (c-independent)
turns out to be positive indicative of the thermodynamical stability of the
uplift. An ALD-gravity-type interpretation can be given to the counter-terms
for(i). Its verified that the black M3-brane entropy S r_h^3 from M-theoretic
thermodynamical methods and the horizon areas of types IIB/IIA/M3-brane
solutions.Comment: 1+58 pages, LaTeX; v4 some minor corrections, results unchange
Formation of a black hole from an AdS spacetime
We shall first discuss motivation for higher dimension even for classical
description of gravitational dynamics and then construct a black hole out of an
anti-deSitter (AdS) spacetime by prescribing a coupling between Gauss-Bonnet
parameter, constant curvature of extra dimensional space and . This is
a creation of pure curvature which establishes the fundamental reciprocity
between matter and gravity/curvature.Comment: 5 pages, 1 figure, Talk given at International Workshop on
Theoretical High Energy Physics at Roorakee, Indi
Neutrino symmetries from high to low scales
Proposed symmetry relations, e.g., quark-lepton complementarity (QLC) or
tribimaximal mixing (TBM), need to be imposed at a high scale GeV characterising the large masses of right-handed neutrinos required
to implement the seesaw mechanism. RG evolution down to the laboratory scale
GeV, generically prone to spoil these relations and their
predicted neutrino mixing patterns, can be made to preserve them by
appropriately constraining the Majorana phases . This is
explicitly demonstrated in the MSSM for two versions of QLC and two versions of
TBM. A preference for (i.e. ) emerges
in each case. Discrimination among the four cases is shown to be possible by
future measurements of .Comment: 8 pages, 2 figures. Talk given at the International Workshop on
Theoretical and Experimental Physics, IIT (Roorkee), March 200
Noncommutative N=2 p-p' System
We analyse several open and mixed sector tree-level amplitudes in N=2 p-p'
systems with a constant magnetic B turned on. The 3-point function vanishes
on-shell. The 4-point function, in the Seiberg-Witten (SW) low energy
limit\cite{SW}, is local, {\it indicating the possible topological nature of
the theory (in the SW low energy limit)} and the {\it possible relation between
noncommutative N=2 p-p' system in two complex dimensions and in the SW limit,
and (non)commutative N=2 p'-p' system in two real dimensions.} We discuss three
extreme noncommutativity limits (after having taken the Seiberg-Witten low
energy limit) of the mixed 3-point function, and get two kinds of commutative
non-associaitive generalized star products. We make some speculative remarks
related to reproducing the above four-point tree level amplitude in the open
sector, from a field theory.Comment: 19 pages, LaTex, 1 ps figure; to appear in IJMP
Gauged B-L unification and cosmology
We discuss some cosmological implications of low energy gauged B-L symmetry
with and without supersymmetry. Generic possibility of leptogenesis from a
domain wall driven first order phase transition is shown to be a characteristic
of such models.Comment: 6 pages. Talk given at IWTHEP 2007, IIT Roorke
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