603 research outputs found
Interactions of War: Exhibiting World War II and the Holocaust
This paper discusses the use of interactive elements in museums that deal with difficult subject matter, such as war or genocide. This research involves interviews with museum personnel at the Columbus Museum in Columbus, Georgia, the National Infantry Museum in Columbus, Georgia, the Museum of History and Holocaust Education in Kennesaw, Georgia, and the World War II Home Front Museum in St. Simons Island, Georgia. This research also discusses the design of a potential exhibit using interactives about women in the resistance movement during Nazi occupation
Non-commutative Unification in Brane World
We point out that in (open) string compactifications with non-zero NS-NS
B-field we can have large Kaluza-Klein thresholds even in the small volume
limit. In this limit the corresponding gauge theory description is in terms of
a compactification on a non-commutative space (e.g., a torus or an orbifold
thereof). Based on this observation we discuss a brane world scenario of
non-commutative unification via Kaluza-Klein thresholds. In this scenario, the
unification scale can be lowered down to the TeV-range, yet the corresponding
compactification radii are smaller than the string length. We discuss a
potential application of this scenario in the context of obtaining mixing
between different chiral generations which is not exponentially suppressed - as
we point out, such mixing is expected to be exponentially suppressed in certain
setups with large volume compactifications. We also point out that T-duality is
broken by certain non-perturbative twisted open string sectors which are
supposed to give rise to chiral generations, so that in the case of a small
volume compactification with a rational B-field we cannot T-dualize to a large
volume description. In this sense, the corresponding field theoretic picture of
unification via Kaluza-Klein thresholds in this setup is best described in the
non-commutative language.Comment: 15 pages, revtex; misprints corrected, clarifying remarks added (to
appear in Phys. Lett. B
Moduli Stabilization in Toroidal Type IIB Orientifolds
We discuss the first step in the moduli stabilization program a la KKLT for a
general class of resolved toroidal type IIB orientifolds. In particular, we
discuss their geometry, the topology of the divisors relevant for the D3-brane
instantons which can contribute to the superpotential, and some non--trivial
aspects of the orientifold action.Comment: 15 pages, 3 figures, contribution to the proceedings of the RTN
workshop "Constituents, Fundamental Forces and Symmetries of the Universe",
Corfu, Greece, 20-26 September 200
Duality in Matrix Theory and Three Dimensional Mirror Symmetry
Certain limits of the duality between M-theory on and IIB on K3
are analyzed in Matrix theory. The correspondence between M-theory five-branes
and ALE backgrounds is realized as three dimensional mirror symmetry.
Non-critical strings dual to open membranes are explicitly described as gauge
theory excitations. We also comment on Type IIA on K3 and the appearance of
gauge symmetry enhancement at special points in the moduli space.Comment: Some changes in the discussion of non-critical strings; few
references added; 18 pages, 5 figure
On the Matrix Description of Calabi-Yau Compactifications
We point out that the matrix description of M-theory compactified on
Calabi-Yau threefolds is in many respects simpler than the matrix description
of a compactification. This is largely because of the differences between
D6 branes wrapped on Calabi-Yau threefolds and D6 branes wrapped on six-tori.
In particular, if we define the matrix theory following the prescription of Sen
and Seiberg, we find that the remaining degrees of freedom are decoupled from
gravity.Comment: 12 pages, harvmac big; comment on 4d N=1 theories change
Evidence for a gravitational Myers effect
An indication for the existence of a collective Myers solution in the
non-abelian D0-brane Born-Infeld action is the presence of a tachyonic mode in
fluctuations around the standard diagonal background. We show that this
computation for non-abelian D0-branes in curved space has the geometric
interpretation of computing the eigenvalues of the geodesic deviation operator
for U(N)-valued coordinates. On general grounds one therefore expects a
geometric Myers effect in regions of sufficiently negative curvature. We
confirm this by explicit computations for non-abelian D0-branes on a sphere and
a hyperboloid. For the former the diagonal solution is stable, but not so for
the latter. We conclude by showing that near the horizon of a Schwarzschild
black hole one also finds a tachyonic mode in the fluctuation spectrum,
signaling the possibility of a near-horizon gravitationally induced Myers
effect.Comment: LaTeX, 23 page
Columbus State University Honors College: Senior Theses, Fall 2019
This is a collection of senior theses written by honors students at Columbus State University in 2019.https://csuepress.columbusstate.edu/honors_theses/1000/thumbnail.jp
D-particles on T^4/Z_n orbifolds and their resolutions
We formulate the effective field theory of a D-particle on orbifolds of
by a cyclic group as a gauge theory in a -bundle over the dual orbifold. We
argue that this theory admits Fayet-Iliopoulos terms analogous to those present
in the case of noncompact orbifolds. In the case, we present some
evidence that turning on such terms resolves the orbifold singularities and may
lead to a surface realized as a blow up of the fixed points of the cyclic
group action.Comment: 34 pages, 3 figures; very minor typos corrected, 2 references adde
The Matrix Formulation of Type IIB Five-Branes
We present a matrix model which interpolates between type IIA and type IIB NS
five-branes. The matrix description involves a three-dimensional bulk quantum
field theory interacting with impurities localized in one spatial direction. We
obtain a dual matrix formulation for the exotic six-dimensional theory on
coincident type IIB NS five-branes by studying the T-dual description in terms
of Kaluza-Klein monopoles in type IIA string theory. After decoupling the bulk
physics, the matrix description reduces to the conformal field theory of the
Coulomb branch for the type IIA matrix string propagating on certain singular
spaces. In many ways, this dual realization of superconformal theories is the
two-dimensional analogue of three-dimensional mirror symmetry.Comment: 15 pages, harvmac; minor changes to the tex
N=2 Heterotic Superstring and its Dual Theory in Five Dimensions
We study quantum effects in five dimensions in heterotic superstring theory
compactified on K_3 x S_1 and analyze the conjecture that its dual effective
theory is eleven-dimensional supergravity compactified on a Calabi-Yau
threefold. This theory is also equivalent to type II superstring theory
compactified on the same Calabi-Yau manifold, in an appropriate large volume
limit. In this limit the conifold singularity disappears and is replaced by a
singularity associated to enhanced gauge symmetries, as naively expected from
the heterotic description. Furthermore, we exhibit the existence of additional
massless states which appear in the strong coupling regime of the heterotic
theory and are related to a different type of singular points on Calabi-Yau
threefolds.Comment: 26 pages, LaTe
- …