pinecone/core-2020-05-10-deduplication huggingface dataset:
Strange Metallic Behavior in Anisotropic Background

We continue our analysis on conductivity in the anisotropic background by
employing the D-brane probe technique, where the D-branes play the role of
charge carriers. The DC and AC conductivity for massless charge carriers are
obtained analytically, while interesting curves for the AC conductivity are
also plotted. For massive charge carriers, we calculate the DC and AC
conductivities in the dilute limit and we fix the parameters in the
Einstein-Maxwell-dilaton theory so that the background exhibits the same
scaling behaviors as those for real-world strange metals. The DC conductivity
at finite density is also computed.Comment: 24 pages, 2 figures, minor modification
AdS Black Hole Solutions in the Extended New Massive Gravity

We have obtained (warped) AdS black hole solutions in the three dimensional
extended new massive gravity. We investigate some properties of black holes and
obtain central charges of the two dimensional dual CFT. To obtain the central
charges, we use the relation between entropy and temperature according to the
AdS/CFT dictionary. For AdS black holes, one can also use the central charge
function formalism which leads to the same results.Comment: 24pages, some organization corrected, minor corrections, references
  added, final published versio
A vector-like fourth generation with a discrete symmetry from Split-UED

Split-UED allows for the possibility that the lowest lying KK excitations of
the Standard Model fermions can be much lighter than the corresponding gauge or
Higgs KK states. This can happen provided the fermion bulk masses are chosen to
be large, in units of the inverse compactification radius, 1/R, and negative.
In this setup, all of the other KK states would be effectively decoupled from
low energy physics. Such a scenario would then lead to an apparent vector-like
fourth generation with an associated discrete symmetry that allows us to
accommodate a dark matter candidate. In this paper the rather unique
phenomenology presented by this picture will be examined.Comment: 13 pages, 5 figure
On Holographic Superconductors with DC Current

We study direct currents in a simple holographic realization of a
superconducting film. We investigate how the presence of a DC current affects
the superconducting phase transition, which becomes first order for any
non-vanishing value of the current, as well as several other properties of the
superconductor such as the AC conductivity. Near the critical temperature we
find a quantitative agreement with several properties of Ginzburg-Landau
superconducting films, for example the squared ratio of the maximal and minimal
condensate is equal to two thirds. We also comment on the extension of our
construction to holographic Josephson junctions.Comment: 22 pages, 7 figures; v2: typos corrected, ref and several
  clarifications added, figure 4 improved, published version; v3: typos
  correcte
A Grassmannian Etude in NMHV Minors

Arkani-Hamed, Cachazo, Cheung and Kaplan have proposed a Grassmannian
formulation for the S-matrix of N=4 Yang-Mills as an integral over link
variables. In parallel work, the connected prescription for computing tree
amplitudes in Witten's twistor string theory has also been written in terms of
link variables. In this paper we extend the six- and seven-point results of
arXiv:0909.0229 and arXiv:0909.0499 by providing a simple analytic proof of the
equivalence between the two formulas for all tree-level NMHV superamplitudes.
Also we note that a simple deformation of the connected prescription integrand
gives directly the ACCK Grassmannian integrand in the limit when the
deformation parameters equal zero.Comment: 17 page
Interaction of Neutrinos with a Cosmological K-essence Scalar

In this paper we study a novel means of coupling neutrinos to a Lorentz
violating background k-essence field. We first look into the effect that
k-essence has on the neutrino dispersion relation and derive a general formula
for the neutrino velocity in the presence on a k-essence background. The
influence of k-essence coupling on neutrino oscillations is then considered. It
is found that a non-diagonal k-essence coupling leads to an oscillation length
that goes like \lambda \sim E^{-1} where E is the energy. This should be
contrasted with the \lambda \sim E dependence seen in the standard mass-induced
mechanism of neutrino oscillations. While such a scenario is not favored
experimentally, it places constraints on the interactions of the neutrino with
a cosmological k-essence scalar background by requiring it to be flavor
diagonal. All non-trivial physical effects discussed here require the speed of
sound to be different from the speed of light and hence are primarily a
consequence of Lorentz violation.Comment: 24 page
A Terminal Velocity on the Landscape: Particle Production near Extra
  Species Loci in Higher Dimensions

We investigate particle production near extra species loci (ESL) in a higher
dimensional field space and derive a speed limit in moduli space at weak
coupling. This terminal velocity is set by the characteristic ESL-separation
and the coupling of the extra degrees of freedom to the moduli, but it is
independent of the moduli's potential if the dimensionality of the field space
is considerably larger than the dimensionality of the loci, D >> d. Once the
terminal velocity is approached, particles are produced at a plethora of nearby
ESLs, preventing a further increase in speed via their backreaction. It is
possible to drive inflation at the terminal velocity, providing a
generalization of trapped inflation with attractive features: we find that more
than sixty e-folds of inflation for sub-Planckian excursions in field space are
possible if ESLs are ubiquitous, without fine tuning of initial conditions and
less tuned potentials. We construct a simple, observationally viable model with
a slightly red scalar power-spectrum and suppressed gravitational waves; we
comment on the presence of additional observational signatures originating from
IR-cascading and individual massive particles. We also show that
moduli-trapping at an ESL is suppressed for D >> d, hindering dynamical
selection of high-symmetry vacua on the landscape based on this mechanism.Comment: 46 pages, 6 figures. V3: typos corrected compared to JHEP version,
  conclusions unchange
MSSM dark matter measurements at the LHC without squarks and sleptons

We examine the case of neutralino dark matter in the focus point region of
the MSSM, in which the scalar sparticles are too heavy to be produced at the
LHC. Whilst it has been previously asserted that the LHC alone would fail to
constrain the properties of the lightest neutralino for such a scenario, we
find that one can obtain good predictions of astrophysical quantities such as
the relic density, annihilation cross-section and direct search cross-sections
by using the shape of the dilepton invariant mass spectrum to constrain
neutralino mixing. We demonstrate our technique using a Bayesian analysis of
the 24 parameter MSSM model space, and in the process introduce a novel way of
improving the LHC results even without assumptions on which new sparticles are
responsible for the kinematic features in the dilepton invariant mass
distribution
Pair Production of small Black Holes in Heterotic String Theories

We study pair production of small BPS BH's in heterotic strings compactified
on tori and in the FHSV model. After recalling the identification of small BH's
in the perturbative BPS spectrum, we compute the tree-level amplitudes for
processes initiated by massless vector bosons or gravitons. We then analyze the
resulting cross sections in terms of energy and angular distributions. Finally,
we briefly comment on scenari with large extra dimensions and on
generalizations of our results to non-BPS, non-extremal and rotating BH's.Comment: 33 page
Topological gravity on the lattice

In this paper we show that a particular twist of $\mathcal{N}=4$ super
Yang-Mills in three dimensions with gauge group SU(2) possesses a set of
classical vacua corresponding to the space of flat connections of the {\it
complexified} gauge group $SL(2,C)$. The theory also contains a set of
topological observables corresponding to Wilson loops wrapping non-trivial
cycles of the base manifold. This moduli space and set of topological
observables is shared with the Chern Simons formulation of three dimensional
gravity and we hence conjecture that the Yang-Mills theory gives an equivalent
description of the gravitational theory. Unlike the Chern Simons formulation
the twisted Yang-Mills theory possesses a supersymmetric and gauge invariant
lattice construction which then provides a possible non-perturbative definition
of three dimensional gravity.Comment: 10 page
Duality and replicas for a unitary matrix model

In a generalized Airy matrix model, a power $p$ replaces the cubic term of
the Airy model introduced by Kontsevich. The parameter $p$ corresponds to
Witten's spin index in the theory of intersection numbers of moduli space of
curves. A continuation in $p$ down to $p= -2$ yields a well studied unitary
matrix model, which exhibits two different phases in the weak and strong
coupling regions, with a third order critical point in-between. The application
of duality and replica to the $p$-th Airy model allows one to recover both the
weak and strong phases of the unitary model, and to establish some new results
for these expansions. Therefore the unitary model is also indirectly a
generating function for intersection numbers.Comment: 18 page, add referece
Giant Magnons in Symmetric Spaces: Explicit N-soliton solutions for
  CP^n, SU(n) and S^n

Giant magnons are one of the main manifestations of integrability on the
string theory side of the AdS/CFT correspondence. Motivated by the recent
advances in their study, especially in the context of the string theory dual of
ABJM theory, we present and prove explicit N-soliton solutions for the relevant
CP^n, SU(n) and S^n sigma models. The proof is based on solving the dressing
method recursion with the help of determinant operations, and our solutions
hold for any choice of vacuum and soliton parameters. We further specialize our
results for the choices that lead to giant magnons, and as an application, we
calculate the classical time delay due to the scattering of an arbitrary number
of CP^2 elementary dyonic magnons. The determinant expressions for our
N-soliton solutions could possibly be used for the derivation of an effective
particle description of magnon scattering.Comment: 34 pages. v2: typos corrected, references updated, clarifications
  added; to appear in JHE
Geometry of Schroedinger Space-Times II: Particle and Field Probes of
  the Causal Structure

We continue our study of the global properties of the z=2 Schroedinger
space-time. In particular, we provide a codimension 2 isometric embedding which
naturally gives rise to the previously introduced global coordinates.
Furthermore, we study the causal structure by probing the space-time with point
particles as well as with scalar fields. We show that, even though there is no
global time function in the technical sense (Schroedinger space-time being
non-distinguishing), the time coordinate of the global Schroedinger coordinate
system is, in a precise way, the closest one can get to having such a time
function. In spite of this and the corresponding strongly Galilean and almost
pathological causal structure of this space-time, it is nevertheless possible
to define a Hilbert space of normalisable scalar modes with a well-defined
time-evolution. We also discuss how the Galilean causal structure is reflected
and encoded in the scalar Wightman functions and the bulk-to-bulk propagator.Comment: 32 page
Modifying the Sum Over Topological Sectors and Constraints on
  Supergravity

The standard lore about the sum over topological sectors in quantum field
theory is that locality and cluster decomposition uniquely determine the sum
over such sectors, thus leading to the usual theta-vacua. We show that without
changing the local degrees of freedom, a theory can be modified such that the
sum over instantons should be restricted; e.g. one should include only
instanton numbers which are divisible by some integer p. This conclusion about
the configuration space of quantum field theory allows us to carefully
reconsider the quantization of parameters in supergravity. In particular, we
show that FI-terms and nontrivial Kahler forms are quantized. This analysis
also leads to a new derivation of recent results about linearized supergravity.Comment: 17 pages, minor change
Probe Branes, Time-dependent Couplings and Thermalization in AdS/CFT

We present holographic descriptions of thermalization in conformal field
theories using probe D-branes in AdS X S space-times. We find that the induced
metrics on Dp-brane worldvolumes which are rotating in an internal sphere
direction have horizons with characteristic Hawking temperatures even if there
is no black hole in the bulk AdS. The AdS/CFT correspondence applied to such
systems indeed reveals thermal properties such as Brownian motions and AC
conductivities in the dual conformal field theories. We also use this framework
to holographically analyze time-dependent systems undergoing a quantum quench,
where parameters in quantum field theories, such as a mass or a coupling
constant, are suddenly changed. We confirm that this leads to thermal behavior
by demonstrating the formation of apparent horizons in the induced metric after
a certain time.Comment: LaTeX, 47 pages, 14 figures; Typos corrected and references added
  (v2); minor corrections, references added(v3
Flux compactification on smooth, compact three-dimensional toric
  varieties

Three-dimensional smooth, compact toric varieties (SCTV), when viewed as real
six-dimensional manifolds, can admit G-structures rendering them suitable for
internal manifolds in supersymmetric flux compactifications. We develop
techniques which allow us to systematically construct G-structures on SCTV and
read off their torsion classes. We illustrate our methods with explicit
examples, one of which consists of an infinite class of toric CP^1 bundles. We
give a self-contained review of the relevant concepts from toric geometry, in
particular the subject of the classification of SCTV in dimensions less or
equal to 3. Our results open up the possibility for a systematic construction
and study of supersymmetric flux vacua based on SCTV.Comment: 27 pages, 10 figures; v2: references, minor typos & improvement
B-L Cosmic Strings in Heterotic Standard Models

E_{8} X E_{8} heterotic string and M-theory, when compactified on smooth
Calabi-Yau manifolds with SU(4) vector bundles, can give rise to softly broken
N=1 supersymmetric theories with the exact matter spectrum of the MSSM,
including three right-handed neutrinos and one Higgs-Higgs conjugate pair of
supermultiplets. These vacua have the SU(3)_{C} X SU(2)_{L} X U(1)_{Y} gauge
group of the standard model augmented by an additional gauged U(1)_{B-L}. Their
minimal content requires that the B-L symmetry be spontaneously broken by a
vacuum expectation value of at least one right-handed sneutrino. The soft
supersymmetry breaking operators can induce radiative breaking of the B-L gauge
symmetry with an acceptable B-L/electroweak hierarchy. In this paper, it is
shown that U(1)_{B-L} cosmic strings occur in this context, potentially with
both bosonic and fermionic superconductivity. We present a numerical analysis
that demonstrates that boson condensates can, in principle, form for theories
of this type. However, the weak Yukawa and gauge couplings of the right-handed
sneutrino suggests that bosonic superconductivity will not occur in the
simplest vacua in this context. The electroweak phase transition also disallows
fermion superconductivity, although substantial bound state fermion currents
can exist.Comment: 41 pages, 5 figure
Decompactifications and Massless D-Branes in Hybrid Models

A method of determining the mass spectrum of BPS D-branes in any phase limit
of a gauged linear sigma model is introduced. A ring associated to monodromy is
defined and one considers K-theory to be a module over this ring. A simple but
interesting class of hybrid models with Landau-Ginzburg fibres over CPn are
analyzed using special Kaehler geometry and D-brane probes. In some cases the
hybrid limit is an infinite distance in moduli space and corresponds to a
decompactification. In other cases the hybrid limit is at a finite distance and
acquires massless D-branes. An example studied appears to correspond to a novel
theory of supergravity with an SU(2) gauge symmetry where the gauge and
gravitational couplings are necessarily tied to each other.Comment: PDF-LaTeX, 34 pages, 2 mps figure
Seiberg-Witten theory, matrix model and AGT relation

We discuss the Penner-type matrix model which has been proposed to explain
the AGT relation between the 2-dimensional Liouville theory and 4-dimensional
N=2 superconformal gauge theories. In our previous communication we have
obtained the spectral curve of the matrix model and showed that it agrees with
that derived from M-theory. We have also discussed the decoupling limit of
massive flavors and proposed new matrix models which describe Seiberg-Witten
theory with flavors N_f=2,3. In this article we explicitly evaluate the free
energy of these matrix models and show that they in fact reproduce the
amplitudes of Seiberg-Witten theory.Comment: 19 pages, 1 figur
On the Thermodynamic Geometry and Critical Phenomena of AdS Black Holes

In this paper, we study various aspects of the equilibrium thermodynamic
state space geometry of AdS black holes. We first examine the
Reissner-Nordstrom-AdS (RN-AdS) and the Kerr-AdS black holes. In this context,
the state space scalar curvature of these black holes is analysed in various
regions of their thermodynamic parameter space. This provides important new
insights into the structure and significance of the scalar curvature. We
further investigate critical phenomena, and the behaviour of the scalar
curvature near criticality, for KN-AdS black holes in two mixed ensembles,
introduced and elucidated in our earlier work arXiv:1002.2538 [hep-th]. The
critical exponents are identical to those in the RN-AdS and Kerr-AdS cases in
the canonical ensemble. This suggests an universality in the scaling behaviour
near critical points of AdS black holes. Our results further highlight
qualitative differences in the thermodynamic state space geometry for electric
charge and angular momentum fluctuations of these.Comment: 1 + 37 Pages, LaTeX, includes 31 figures. A figure and a
  clarification added
A simple model for particle physics and cosmology

We propose a simple extension of the minimal supersymmetric standard model by
introducing a gauge singlet in addition to right-handed neutrinos. The model
resolves the strong CP problem by Pecci-Quinn symmetry, explains the origin of
left-handed neutrino masses as well as MSSM $\mu$-parameter. It also gives rise
to thermal inflation, baryogenesis and dark matter in a remarkably consistent
way. Interestingly, resolution of moduli problem by thermal inflation
constrains tightly axion coupling constant and flaton decay temperature to be
$f_a \sim 10^{12} \GeV$ and $T_\mathrm{d} \sim 100 \MeV$, respectively. Model
parameters in this case are likely to give right amount of baryon asymmetry and
dark matter at present. The main component of dark matter is expected to be the
axino whose mass is nearly fixed to be about $1 \GeV$.Comment: 20 pages, 1 figure; added footnotes and references for section 1 and
  2, a footnote replaced with a new paragraph in section
QCD with Chemical Potential in a Small Hyperspherical Box

To leading order in perturbation theory, we solve QCD, defined on a small
three sphere in the large N and Nf limit, at finite chemical potential and map
out the phase diagram in the (mu,T) plane. The action of QCD is complex in the
presence of a non-zero quark chemical potential which results in the sign
problem for lattice simulations. In the large N theory, which at low
temperatures becomes a conventional unitary matrix model with a complex action,
we find that the dominant contribution to the functional integral comes from
complexified gauge field configurations. For this reason the eigenvalues of the
Polyakov line lie off the unit circle on a contour in the complex plane. We
find at low temperatures that as mu passes one of the quark energy levels there
is a third-order Gross-Witten transition from a confined to a deconfined phase
and back again giving rise to a rich phase structure. We compare a range of
physical observables in the large N theory to those calculated numerically in
the theory with N=3. In the latter case there are no genuine phase transitions
in a finite volume but nevertheless the observables are remarkably similar to
the large N theory.Comment: 44 pages, 18 figures, jhep3 format. Small corrections and
  clarifications added in v3. Conclusions cleaned up. Published versio
On The Stability Of Non-Supersymmetric AdS Vacua

We consider two infinite families of Non-Supersymmetric $AdS_4$ vacua, called
Type 2) and Type 3) vacua, that arise in massive IIA supergravity with flux. We
show that both families are perturbatively stable. We then examine
non-perturbative decays of these vacua to other supersymmetric and
non-supersymmetric $AdS_4$ vacua mediated by instantons in the thin wall
approximation. We find that many decays are ruled out since the tension of the
interpolating domain wall is too big compared to the energy difference in AdS
units. In fact, within our approximations no decays of Type 2) vacua are
allowed, although some decays are only marginally forbidden. This can be
understood in terms of a "pairing symmetry" in the landscape which relate Type
2) vacua with supersymmetric ones of the same energy.Comment: 50 pages, Minor changes in section 2.2.
Intersecting D4-branes Model of Holographic QCD and Tachyon Condensation

We consider the intersecting D4-brane and anti-D4-brane model of holographic
QCD, motivated by the model that has recently been suggested by Van Raamsdonk
and Whyte. We analyze such D4-branes by the use of the action with a
bi-fundamental ``tachyon'' field, so that we find the classical solutions
describing the intersecting D4-branes and the U-shaped D4-branes. We show that
the ``tachyon'' field in the bulk theory provides a current quark mass and a
quark condensate to the dual gauge theory and that the lowest modes of mesons
obtain mass via tachyon condensation. Then evaluating the properties of a pion,
one can reproduce Gell-Mann-Oakes-Renner relation.Comment: 24 pages, 5 figures; v2: refs. added; v3: discussions on Chern-Simons
  terms are adde
Holographic constraint and effective field theories with N-species

Effective field theories that manifest UV/IR mode mixing in such a way as to
be valid for arbitrarily large volumes, can be used for gravitational,
non-black hole events to be accounted for. In formulating such theories with a
large number of particle species $N$, we employ constraints from the muon
$g-2$, higher-dimensional operator corrections due to the required UV and IR
cutoffs as well as the RG evolution in a conventional field-theoretical model
in curved space. While in general our bounds on $N$ do reflect $N \simeq
10^{32}$, a bound motivated by the solution to the hierarchy problem in alike
theories and obtained by the fact that strong gravity has not been seen in the
particle collisions, the bound from the muon $g-2$ turns out to be much
stronger, $N \lsim 10^{19}$. For systems on the verge of gravitational
collapse, this bound on $N$ is far too restrictive to allow populating a large
gap in entropy between those systems and that of black holes of the same size.Comment: 7 pages, version to appear in JHE