1,138 research outputs found
Quantum Kerr tunneling vacua on a -brane: An emergent Kerr black hole in five dimensions
We revisit a non-perturbative space-time curvature theory, underlying a two
form U(1) gauge dynamics, on a D4-brane. In particular, two different gauge
choices for a two form are explored underlying the dynamics of a geometric
torsion in a second order formalism. We obtain two non-extremal quantum Kerr
geometries in five dimensions on a pair of -brane in a type IIA
superstring theory. The quantum vacua are described by a vanishing torsion in a
gauge choice, underlying a geometric realization, on a non-BPS brane. It is
argued that the quantum Kerr vacua undergo tunneling and lead to a five
dimensional Kerr black hole in Einstein vacuum. A low energy limit in the
quantum Kerr vacua further re-assures an emergent Kerr black hole.Comment: 21 pages, 8 figure
Emergent gravity/Non-linear U(1) gauge theory correspondence
Kaluza-Klein gravity is revisted, with renewed interest, in a type IIB string
theory on . The irreducible curvature tensors are worked out in
the, T-dual, emergent gravity in 4D to yield a non-linear U(1) gauge theory.
Interestingly, the T-duality may be seen to describe an open/closed string
duality at a self-dual string coupling. The obtained deformation in
black hole is analyzed to introduce the notion of temperature in the emergent
gravity underlying the recent idea of entropic force.Comment: 6 page
Quintessence and effective AdS brane geometries
A geometric torsion dynamics leading to an effective curvature in a second
order formalism on a D4-brane is revisited with a renewed interest. We obtain
two effective brane geometries on a vacuum created pair of -brane. One of them is shown to describe an AdS Schwarzschild spinning
black hole and the other is shown to describe a spinning black hole bound
state. It is argued that a D-instanton in a vacuum created anti D3-brane within
a pair may describe a quintessence. It may seen to incorporate a varying vacuum
energy density in a brane universe. We consider the effective curvature scalar
on to analyze torsion-less geometries on a vacuum created pair
of -brane. The emergent brane is shown to describe a
Schwarzschild and a Reissner-Nordstrom (RN) geometries in presence of extra
dimension(s).Comment: 20 pages, expanded discussion and added referenc
Emergent Schwarzschild and Reissner-Nordstrom black holes in 4D: An effective curvature sourced by a B2-field on a D4-brane
We obtain a Schwarzschild and a Reissner-Nordstrom emergent black holes, by
exploring the torsion dynamics in a generalized curvature formulation,
underlying an effective D4-brane on S1. It is shown that a constant effective
metric, sourced by a background fluctuation in B2-potential, on a D3-brane
receives a dynamical quantum correction in presence of an electric charge.Comment: 7-pages, minor corrections, references added, to appear in Physical
Review
Quintessence and effective RN de Sitter brane geometries
We revisit an effective space-time torsion curvature in a second order
formalism, underlying the non-linear gauge dynamics, of a two form on a
-brane in type IIA superstring theory. The formalism incorporates the
significance of a global NS two form into the theory via its perturbative
coupling to a dynamical two form. In particular, we explore the non-linear
gauge dynamics on a -brane in presence of a non-trivial background metric.
The fact that the global modes of a NS two form in an open string theory
sources the background metric on a -brane may hint at the existence of an
anti -brane in the formalism. An effective de Sitter universe is shown to
emerge on a vacuum created pair of -brane by a local two form at
the past horizon with a Big Bang. We obtain a number of 4D de Sitter quantum
black holes, including a Reissner-Nordstrom vacuum, with and without a
propagating torsion. The quantum black holes are shown to be free from
curvature singularity at . In a low energy limit, the
nonperturbative correction sourced by a torison may seen to be insignificant.
The quantum black hole undergoes an expansion in the limit and presumably
identifies with the Einstein vacuum. Interestingly our analysis reveals a
plausible quintessence (axion) on an anti -brane which may source the dark
energy in a -brane universe. Arguably a brane universe moves away from its
anti-brane due to the conjectured repulsive gravity underlying the
quintessence. It leads to a growth in extra fifth dimension between a brane and
an anti-brane which may provide a clue behind an accelerating universe observed
in cosmology.Comment: 29 page
Fascioliasis Control: In Vivo and In Vitro Phytotherapy of Vector Snail to Kill Fasciola Larva
Snail is one of the important components of an aquatic ecosystem, it acts as intermediate host of Fasciola species. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. Life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria in the snail body. In vivo and in vitro toxicity of the plant products and their active component such as citral, ferulic acid, umbelliferone, azadirachtin, and allicin against larva of Fasciola in infected snail Lymnaea acuminata were tested. Mortality of larvae were observed at 2 h, 4 h, 6 h, and 8 h, of treatment. In in vivo treatment, azadirachtin caused highest mortality in redia and cercaria larva (8 h, LC50 0.11, and 0.05 mg/L) whereas in in vitro condition allicin was highly toxic against redia and cercaria (8 h, LC50 0.01, and 0.009 mg/L). Toxicity of citral was lowest against redia and cercaria larva
GARBHINI CHARDI (EMESIS GRAVIDARUM), ITS MANAGEMENT IN AYURVEDA
Acharya charaka has given specific importance to pregnant women and has compared them with oil filled vessel, which can be split by little displacement and to provide proper attention during pregnancy. Ayurvedic classics have mentioned Garbhini Chardi as one among the Vyakta garbha lakshanas, which can be correlated with emesis gravidarum. Emesis Gravidarum is a worldwide common obstetrical problem seen in the first trimester of pregnancy in about 50% of pregnant women.Nausea and vomiting tend to be worse in the morning termed Morning sickness, they frequently continue throughout the day. Vomiting in the early weeks of pregnancy is very common. If we do not correct the simple vomiting it leads to severe. So one should take care to treat this condition in initial stage and prevent complications. Different formulations and recipes have been mentioned in Ayurvedic classics which can easily be incorporated in day today life by a pregnant woman for Chardi. These are easy to prepare & easily available. Hence in this study an effort is made to list out simple & effective management of Garbhini Chardi with the help of various herbal preparations
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