377 research outputs found
Time-dependent Aharonov-Bohm effect on the noncommutative space
We study the time-dependent Aharonov-Bohm effect on the noncommutative space.
Because there is no net Aharonov-Bohm phase shift in the time-dependent case on
the commutative space, therefore, a tiny deviation from zero indicates new
physics. Based on the Seiberg-Witten map we obtain the gauge invariant and
Lorentz covariant Aharonov-Bohm phase shift in general case on noncommutative
space. We find there are two kinds of contribution: momentum-dependent and
momentum-independent corrections. For the momentum-dependent correction, there
is a cancellation between the magnetic and electric phase shifts, just like the
case on the commutative space. However, there is a non-trivial contribution in
the momentum-independent correction. This is true for both the time-independent
and time-dependent Aharonov-Bohm effects on the noncommutative space. However,
for the time-dependent Aharonov-Bohm effect, there is no overwhelming
background which exists in the time-independent Aharonov-Bohm effect on both
commutative and noncommutative space. Therefore, the time-dependent
Aharonov-Bohm can be sensitive to the spatial noncommutativity. \draftnote{The
net correction is proportional to the product of the magnetic fluxes through
the fundamental area represented by the noncommutative parameter , and
through the surface enclosed by the trajectory of charged particle.} More
interestingly, there is an anti-collinear relation between the logarithms of
the magnetic field and the averaged flux (N is the number of
fringes shifted). This nontrivial relation can also provide a way to test the
spatial noncommutativity. For , our estimation on the
experimental sensitivity shows that it can reach the scale. This
sensitivity can be enhanced by using stronger magnetic field strength, larger
magnetic flux, as well as higher experimental precision on the phase shift.Comment: 12 pages, 1 figure; v2, accepted version by PL
Moduli Stabilization in Type IIB Flux Compactifications
In the present paper, we reexamine the moduli stabilization problem of the
Type IIB orientifolds with one complex structure modulus in a modified two-step
procedure. The full superpotential including both the 3-form fluxes and the
non-perturbative corrections is used to yield a F-term potential. This
potential is simplified by using one optimization condition to integrate the
dilaton field out. It is shown that having a locally stable supersymmetric
Anti-deSitter vacuum is not inevitable for these orientifolds, which depend
strongly upon the details of the flux parameters. For those orientifolds that
have stable/metastable supersymmetry-broken minima of the F-term potential, the
deSitter vacua might emerge even without the inclusion of the uplifting
contributions.Comment: 10 pages, LaTeX2e style. The paper is rewritten in ver3 with more
references adde
Warped embeddings between Einstein manifolds
Warped embeddings from a lower dimensional Einstein manifold into a higher
dimensional one are analyzed. Explicit solutions for the embedding metrics are
obtained for all cases of codimension 1 embeddings and some of the codimension
n>1 cases. Some of the interesting features of the embedding metrics are
pointed out and potential applications of the embeddings are discussed.Comment: 12 pages, to appear in Mod. Phys. Lett.
QCD Glueball Masses from AdS-6 Black Hole Description
By using the generalized version of gauge/gravity correspondence, we study
the mass spectra of several typical QCD glueballs in the framework of
AdS black hole metric of Einstein gravity theory. The obtained glueball
mass spectra are numerically in agreement with those from the AdS
black hole metric of the 11-dimensional supergravity.Comment: 10 pages, references updated and minor change
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