pinecone/core-2020-05-10-deduplication huggingface dataset:
A minimalistic pure spinor sigma-model in AdS

The $b$-ghost of the pure spinor formalism in a general curved background is
not holomorphic. For such theories, the construction of the string measure
requires the knowledge of the action of diffeomorphisms on the BV phase space.
We construct such an action for the pure spinor sigma-model in $AdS_5\times
S^5$. From the point of view of the BV formalism, this sigma-model belongs to
the class of theories where the expansion of the Master Action in antifields
terminates at the quadratic order. We show that it can be reduced to a simpler
degenerate sigma-model, preserving the AdS symmetries. We construct the action
of the algebra of worldsheet vector fields on the BV phase space of this
minimalistic sigma-model, and explain how to lift it to the original model.Comment: 35pp. LaTeX; v2,3,4: corrections, improved presentation, v5: added
  Section 5.4 (gluing the BV phase space from charts) and Section
Beyond $a=c$: Gravitational Couplings to Matter and the Stress Tensor
  OPE

We derive constraints on the operator product expansion of two stress tensors
in conformal field theories (CFTs), both generic and holographic. We point out
that in large $N$ CFTs with a large gap to single-trace higher spin operators,
the stress tensor sector is not only universal, but isolated: that is, $\langle
TT{\cal O}\rangle=0$, where ${\cal O}\neq T$ is a single-trace primary. We show
that this follows from a suppression of $\langle TT{\cal O}\rangle$ by powers
of the higher spin gap, $\Delta_{\rm gap}$, dual to the bulk mass scale of
higher spin particles, and explain why $\langle TT{\cal O}\rangle$ is a more
sensitive probe of $\Delta_{\rm gap}$ than $a-c$ in 4d CFTs. This result
implies that, on the level of cubic couplings, the existence of a consistent
truncation to Einstein gravity is a direct consequence of the absence of higher
spins. By proving similar behavior for other couplings $\langle T{\cal
O}_1{\cal O}_2\rangle$ where ${\cal O}_i$ have spin $s_i\leq 2$, we are led to
propose that $1/\Delta_{\rm gap}$ is the CFT "dual" of an AdS derivative in a
classical action. These results are derived by imposing unitarity on mixed
systems of spinning four-point functions in the Regge limit. Using the same
method, but without imposing a large gap, we derive new inequalities on these
three-point couplings that are valid in any CFT. These are generalizations of
the Hofman-Maldacena conformal collider bounds. By combining the collider bound
on $TT$ couplings to spin-2 operators with analyticity properties of CFT data,
we argue that all three tensor structures of $\langle TTT\rangle$ in the
free-field basis are nonzero in interacting CFTs.Comment: 42+25 pages. v2: added refs, minor change
Can we observe fuzzballs or firewalls?

In the fuzzball paradigm the information paradox is resolved because the
black hole is replaced by an object with no horizon. One may therefore ask if
observations can distinguish a traditional hole from a fuzzball. We find: (a)
It is very difficult to reflect quanta off the surface of a fuzzball, mainly
because geodesics starting near the horizon radius cannot escape to infinity
unless their starting direction is very close to radial. (b) If infalling
particles interact with the emerging radiation before they are engulfed by the
horizon, then we say that we have a `firewall behavior'. We consider several
types of interactions, but find no evidence for firewall behavior in any theory
that obeys causality. (c) Photons with wavelengths {\it larger} than the black
hole radius can be scattered off the emerging radiation, but a very small
fraction of the backscattered photons will be able to escape back to infinity.Comment: 52 pages, 4 figure
String Theory of Supertubes

String theory on AdS3 backgrounds arises as an IR limit of Little String
Theory on NS5-branes. A wide variety of holographic RG flows from the fivebrane
theory in the UV to (orbifolds of) AdS3 in the IR is amenable to exact
treatment in worldsheet string theory as a class of null-gauged WZW models. The
condensate of stringy winding operators which resolves the near-source
structure of fivebranes on the Coulomb branch plays a crucial role in AdS3,
revealing stringy structure invisible to the supergravity approximation. The
D-brane sector contains precursors of the long strings which dominate black
hole entropy in the dual spacetime CFT.Comment: 59 pages, 11 figure
Probing Transverse-Momentum Dependent Evolution With Groomed Jets

We propose an observable which involves measuring the properties (transverse
momentum $p_{h\perp}$ and energy fraction $z_h$) of an identified hadron inside
a groomed jet. The jet is identified with an anti-kT/CA algorithm and is
groomed by implementing the modified mass drop procedure with an energy cut-off
parameter $z_{cut}$. The transverse momentum of the hadron inside the jet is
measured with respect to the groomed jet axis. We obtain a factorization
theorem in the framework of Soft Collinear Effective Theory (SCET), to define a
Transverse Momentum Dependent Fragmenting Jet Function (TMDFJF). The TMDFJF is
factorized into collinear and collinear soft modes by matching onto SCET$_+$.
We resum large logarithms in $E_J/p_{h\perp}$, where $E_J$ is the ungroomed jet
energy, to NLL accuracy and apply this formalism for computing the shape of the
$p_{h\perp}$ distribution of a pion produced in an $e^+ +e^-$ collision. We
observe that the introduction of grooming makes this observable insensitive to
non-global logarithms and particularly sensitive to non-perturbative physics of
the transverse momentum dependent evolution at low values of $p_{h\perp}$,
which can be probed in the variation of the cut-off parameter $z_{cut}$ of the
groomer. We discuss how this observable can be used to distinguish between
non-perturbative models that describe universal TMD evolution and provide a
window into the three dimensional structure of hadrons.Comment: 23 pages, 4 figure
Vacuum fluctuations of a scalar field near a reflecting boundary and
  their effects on the motion of a test particle

The contribution from quantum vacuum fluctuations of a real massless scalar
field to the motion of a test particle that interacts with the field in the
presence of a perfectly reflecting flat boundary is here investigated. There is
no quantum induced dispersions on the motion of the particle when it is alone
in the empty space. However, when a reflecting wall is introduced, dispersions
occur with magnitude dependent on how fast the system evolves between the two
scenarios. A possible way of implementing this process would be by means of an
idealized sudden switching, for which the transition occurs instantaneously.
Although the sudden process is a simple and mathematically convenient
idealization it brings some divergences to the results, particularly at a time
corresponding to a round trip of a light signal between the particle and the
wall. It is shown that the use of smooth switching functions, besides
regularizing such divergences, enables us to better understand the behavior of
the quantum dispersions induced on the motion of the particle. Furthermore, the
action of modifying the vacuum state of the system leads to a change in the
particle energy that depends on how fast the transition between these states is
implemented. Possible implications of these results to the similar case of an
electric charge near a perfectly conducting wall are discussed.Comment: 17 pages, 8 figure
Integrability of Conformal Blocks I: Calogero-Sutherland Scattering
  Theory

Conformal blocks are the central ingredient of the conformal bootstrap
programme. We elaborate on our recent observation that uncovered a relation
with wave functions of an integrable Calogero-Sutherland Hamiltonian in order
to develop a systematic theory of conformal blocks. Our main goal here is to
review central ingredients of the Heckman-Opdam theory for scattering states of
Calogero-Sutherland models with special emphasis to the relation with scalar
4-point blocks. We will also discuss a number of direct consequences for
conformal blocks, including a new series expansion for blocks of arbitrary
complex spin and a complete analysis of their poles and residues. Applications
to the Froissart-Gribov formula for conformal field theory, as well as
extensions to spinning blocks and defects are briefly discussed before we
conclude with an outlook on forthcoming work concerning algebraic consequences
of integrability.Comment: 65 pages, 6 figure
Space-Time in the SYK Model

We consider the question of identifying the bulk space-time of the SYK model.
Focusing on the signature of emergent space-time of the (Euclidean) model, we
explain the need for non-local (Radon-type) transformations on external legs of
$n$-point Green's functions. This results in a dual theory with Euclidean AdS
signature with additional leg-factors. We speculate that these factors
incorporate the coupling of additional bulk states similar to the discrete
states of 2d string theory.Comment: 24 pages, 1 figure; v2: published version in JHEP with minor
  correction
The Interplay Between GUT and Flavour Symmetries in a Pati-Salam x S4
  Model

Both Grand Unified symmetries and discrete flavour symmetries are appealing
ways to describe apparent structures in the gauge and flavour sectors of the
Standard Model. Both symmetries put constraints on the high energy behaviour of
the theory. This can give rise to unexpected interplay when building models
that possess both symmetries. We investigate on the possibility to combine a
Pati-Salam model with the discrete flavour symmetry $S_4$ that gives rise to
quark-lepton complementarity. Under appropriate assumptions at the GUT scale,
the model reproduces fermion masses and mixings both in the quark and in the
lepton sectors. We show that in particular the Higgs sector and the running
Yukawa couplings are strongly affected by the combined constraints of the Grand
Unified and family symmetries. This in turn reduces the phenomenologically
viable parameter space, with high energy mass scales confined to a small region
and some parameters in the neutrino sector slightly unnatural. In the allowed
regions, we can reproduce the quark masses and the CKM matrix. In the lepton
sector, we reproduce the charged lepton masses, including bottom-tau
unification and the Georgi-Jarlskog relation as well as the two known angles of
the PMNS matrix. The neutrino mass spectrum can present a normal or an inverse
hierarchy, and only allowing the neutrino parameters to spread into a range of
values between $\lambda^{-2}$ and $\lambda^2$, with $\lambda\simeq0.2$.
Finally, our model suggests that the reactor mixing angle is close to its
current experimental bound.Comment: 62 pages, 4 figures; references added, version accepted for
  publication in JHE
More loops and legs in Higgs-regulated N=4 SYM amplitudes

We extend the analysis of Higgs-regulated planar amplitudes of N=4
supersymmetric Yang-Mills theory to four loops for the four-gluon amplitude and
to two loops for the five-gluon amplitude. Our calculations are consistent with
a proposed all-loop ansatz for planar MHV n-gluon amplitudes that is the analog
of the BDS ansatz in dimensional regularization. In all cases considered, we
have verified that the IR-finite parts of the logarithm of the amplitudes have
the same dependence on kinematic variables as the corresponding functions in
dimensionally-regulated amplitudes (up to overall additive constants, which we
determine). We also study various Regge limits of N=4 SYM planar n-gluon
amplitudes. Euclidean Regge limits of Higgs-regulated n \geq 4 amplitudes yield
results similar in form to those found using dimensional regularization, but
with different expressions for the gluon trajectory and Regge vertices
resulting from the different regulator scheme. We also show that the Regge
limit of the four-gluon amplitude is dominated at next-to-leading-log order by
vertical ladder diagrams together with the class of vertical ladder diagrams
with a single H-shaped insertion.Comment: 34 pages, 5 figures; v2: references added; v3: minor changes,
  published versio
Constraints on a very light CP-odd Higgs of the NMSSM and other
  axion-like particles

In the NMSSM, a light CP-odd Higgs arises due to spontaneous breaking of
approximate symmetries such as Peccei-Quinn or R-symmetry and is motivated by
string theory. The case when it is heavier than two muons is well studied and
constrained. We analyze various meson decay, g-2, beam dump and reactor bounds
on the CP-odd Higgs with mass below the muon threshold, in particular,
addressing the question how light a CP-odd Higgs can be. We find that it has to
be heavier than 210 MeV or have couplings to fermions 4 orders of magnitude
below those of the Standard Model Higgs. Our analysis applies more generally to
couplings of a light pseudoscalar to matter.Comment: 21 pages, 4 figures; v2: references added, matches version published
  in JHE
Long-lived stops in MSSM scenarios with a neutralino LSP

This work investigates the possibility of a long-lived stop squark in
supersymmetric models with the neutralino as the lightest supersymmetric
particle (LSP). We study the implications of meta-stable stops on the sparticle
mass spectra and the dark matter density. We find that in order to obtain a
sufficiently long stop lifetime so as to be observable as a stable R-hadron at
an LHC experiment, we need to fine tune the mass degeneracy between the stop
and the LSP considerably. This increases the stop-neutralino coanihilation
cross section, leaving the neutralino relic density lower than what is expected
from the WMAP results for stop masses ~1.5 TeV/c^2. However, if such scenarios
are realised in nature we demonstrate that the long-lived stops will be
produced at the LHC and that stop-based R-hadrons with masses up to 1 TeV/c^2
can be detected after one year of running at design luminosity
Holographic Penta and Hepta Quark State in Confining Gauge Theories

We study a new embedding solutions of D5 brane in an asymptotic
AdS${}_5\times S^5$ space-time, which is dual to a confining $SU(N_c)$ gauge
theory. The D5 brane is wrapped on $S^5$ as in the case of the vertex of
holographic baryon. However, the solution given here is different from the
usual baryon vertex in the point that it couples to $k$-anti-quarks and $N_c+k$
quarks on the opposite two points of $S^5$, the north and south poles,
respectively. The total quark number of this state is preserved as $N_c$ when
minus one is assigned to anti-quark, then it forms a color singlet like the
baryon. However, this includes anti-quarks and quarks, whose number is larger
than that of the baryon. When we set as $N_c=3$, we find the so called penta
and hepta-quark states. We study the dynamical properties of these states by
solving the vertex and string configurations for such states. The mass spectra
of these states and the tension of the stretched vertex are estimated, and they
are compared with that of the baryon.Comment: 24 pages, 6 figure
Generalized metric formulation of double field theory

The generalized metric is a T-duality covariant symmetric matrix constructed
from the metric and two-form gauge field and arises in generalized geometry. We
view it here as a metric on the doubled spacetime and use it to give a simple
formulation with manifest T-duality of the double field theory that describes
the massless sector of closed strings. The gauge transformations are written in
terms of a generalized Lie derivative whose commutator algebra is defined by a
double field theory extension of the Courant bracket.Comment: 36 pages, v2: minor correction
The continuum limit of the static-light meson spectrum

We investigate the continuum limit of the low lying static-light meson
spectrum using Wilson twisted mass lattice QCD with N_f = 2 dynamical quark
flavours. We consider three values of the lattice spacing a ~ 0.051 fm, 0.064
fm, 0.080 fm and various values of the pion mass in the range 280 MeV < m_PS <
640 MeV. We present results in the continuum limit for light cloud angular
momentum j = 1/2, 3/2, 5/2 and for parity P = +, -. We extrapolate our results
to physical quark masses, make predictions regarding the spectrum of B and B_s
mesons and compare with available experimental results.Comment: 18 pages, 3 figure
Realization of Center Symmetry in Two Adjoint Flavor Large-N Yang-Mills

We report on the results of numerical simulations of $SU(N)$ lattice Yang
Mills with two flavors of (light) Wilson fermion in the adjoint representation.
We analytically and numerically address the question of center symmetry
realization on lattices with $\Gamma$ sites in each direction in the large-$N$
limit. We show, by a weak coupling calculation that, for massless fermions,
center symmetry realization is independent of $\Gamma$, and is unbroken. Then,
we extend our result by conducting simulations at non zero mass and finite
gauge coupling. Our results indicate that center symmetry is intact for a range
of fermion mass in the vicinity of the critical line on lattices of volume
$2^4$. This observation makes it possible to compute infinite volume physical
observables using small volume simulations in the limit $N\to\infty$, with
possible applications to the determination of the conformal window in gauge
theories with adjoint fermions.Comment: 15 pages, 9 figure
Non-Abelian vortex dynamics: Effective world-sheet action

The low-energy vortex effective action is constructed in a wide class of
systems in a color-flavor locked vacuum, which generalizes the results found
earlier in the context of U(N) models. It describes the weak fluctuations of
the non-Abelian orientational moduli on the vortex worldsheet. For instance,
for the minimum vortex in SO(2N) x U(1) or USp(2N) x U(1) gauge theories, the
effective action found is a two-dimensional sigma model living on the Hermitian
symmetric spaces SO(2N)/U(N) or USp(2N)/U(N), respectively. The fluctuating
moduli have the structure of that of a quantum particle state in spinor
representations of the GNO dual of the color-flavor SO(2N) or USp(2N) symmetry,
i.e. of SO(2N) or of SO(2N+1). Applied to the benchmark U(N) model our
procedure reproduces the known CP(N-1) worldsheet action; our recipe allows us
to obtain also the effective vortex action for some higher-winding vortices in
U(N) and SO(2N) theories.Comment: LaTeX, 25 pages, 0 figure
Lifshitz spacetimes from AdS null and cosmological solutions

We describe solutions of 10-dimensional supergravity comprising null
deformations of $AdS_5\times S^5$ with a scalar field, which have $z=2$
Lifshitz symmetries. The bulk Lifshitz geometry in 3+1-dimensions arises by
dimensional reduction of these solutions. The dual field theory in this case is
a deformation of the N=4 super Yang-Mills theory. We discuss the holographic
2-point function of operators dual to bulk scalars. We further describe
time-dependent (cosmological) solutions which have anisotropic Lifshitz scaling
symmetries. We also discuss deformations of $AdS\times X$ in 11-dimensional
supergravity, which are somewhat similar to the solutions above. In some cases
here, we expect the field theory duals to be deformations of the Chern-Simons
theories on M2-branes stacked at singularities.Comment: Latex, 29pgs, v3. references, minor clarifications (subsection on
  Lifshitz geometry seen by scalar probes) added, to appear in JHE
Thermodynamics of Large N Gauge Theories with Chemical Potentials in a
  1/D Expansion

In order to understand thermodynamical properties of N D-branes with chemical
potentials associated with R-symmetry charges, we study a one dimensional large
N gauge theory (bosonic BFSS type model) as a first step. This model is
obtained through a dimensional reduction of a 1+D dimensional SU(N) Yang-Mills
theory and we use a 1/D expansion to investigate the phase structure. We find
three phases in the \mu-T plane. We also show that all the adjoint scalars
condense at large D and obtain a mass dynamically. This dynamical mass protects
our model from the usual perturbative instability of massless scalars in a
non-zero chemical potential. We find that the system is at least meta-stable
for arbitrary large values of the chemical potentials in D \to \infty limit. We
also explore the existence of similar condensation in higher dimensional gauge
theories in a high temperature limit. In 2 and 3 dimensions, the condensation
always happens as in one dimensional case. On the other hand, if the dimension
is higher than 4, there is a critical chemical potential and the condensation
happens only if the chemical potentials are below it.Comment: 37 pages, 4 figures; v2: minor corrections, references added; v3:
  minor corrections, to appear in JHE
Analytic explanation of the strong spin-dependent amplification in
  Hawking radiation from rotating black holes

Numerical studies of black hole greybody factors indicate that Hawking
emission from a highly rotating black hole is strongly spin dependent, with
particles of highest spin (gravitons) dominating the energy spectrum. So far,
there has been no analytic explanation or description of this effect. Using
"gravitomagnetism", or the formal analogy between the Maxwell's field equations
for electro- magnetism and Einstein's equations for gravity, we were able to
establish a link between the spin of the rotating black hole and spin of an
emitted particle. Namely, the intrinsic spin of the particle creates a "mass
dipole moment" which interacts with external gravitomagnetic field whose source
is the rotation of the black hole. We showed that a rotating black hole prefers
to shed its spin, i.e. tends to emit particles with the spin parallel to its
own. We also showed that the probability for emission grows with the increasing
spin of the emitted particles. The amplification factors can be huge if a black
hole is highly rotating, i.e. close to extremal. When applied to central
galactic black holes, the same physical mechanism indicate that particles
orbiting around these black holes should have spins strongly correlated with
the spin of the black hole, which may have implications for cosmic rays
believed to be coming from these regions of space.Comment: Published in JHEP; one reference correcte
Degenerate distributions in complex Langevin dynamics: one-dimensional
  QCD at finite chemical potential

We demonstrate analytically that complex Langevin dynamics can solve the sign
problem in one-dimensional QCD in the thermodynamic limit. In particular, it is
shown that the contributions from the complex and highly oscillating spectral
density of the Dirac operator to the chiral condensate are taken into account
correctly. We find an infinite number of classical fixed points of the Langevin
flow in the thermodynamic limit. The correct solution originates from a
continuum of degenerate distributions in the complexified space.Comment: 20 pages, several eps figures, minor comments added, to appear in
  JHE