pinecone/core-2020-05-10-deduplication huggingface dataset:
Twisted Partition Functions and $H$-Saddles

While studying supersymmetric $G$-gauge theories, one often observes that a
zero-radius limit of the twisted partition function $\Omega^G$ is computed by
the partition function ${\cal Z}^G$ in one less dimensions. We show that this
type of identification fails generically due to integrations over Wilson lines.
Tracing the problem, physically, to saddles with reduced effective theories, we
relate $\Omega^G$ to a sum of distinct ${\cal Z}^H$'s and classify the latter,
dubbed $H$-saddles. This explains why, in the context of pure Yang-Mills
quantum mechanics, earlier estimates of the matrix integrals ${\cal Z}^{G}$ had
failed to capture the recently constructed bulk index ${\cal I}^G_{\rm bulk}$.
The purported agreement between 4d and 5d instanton partition functions,
despite such subtleties also present in the ADHM data, is explained.Comment: 37 pages; a new appendix on examples with high rank classical group
Entanglement, space-time and the Mayer-Vietoris theorem

Entanglement appears to be a fundamental building block of quantum gravity
leading to new principles underlying the nature of quantum space-time. One such
principle is the ER-EPR duality. While supported by our present intuition, a
proof is far from obvious. In this article I present a first step towards such
a proof, originating in what is known to algebraic topologists as the
Mayer-Vietoris theorem. The main result of this work is the re-interpretation
of the various morphisms arising when the Mayer-Vietoris theorem is used to
assemble a torus-like topology from more basic subspaces on the torus in terms
of quantum information theory resulting in a quantum entangler gate (Hadamard
and c-NOT)
Measurement of the $J/\psi$ pair production cross-section in pp collisions at $\sqrt{s}$ = 13 TeV

The production cross-section of $J/\psi$ pairs is measured using a data sample of pp collisions collected by the LHCb experiment at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 279 $\pm$ 11 pb$^{−1}$. The measurement is performed for J/ψ mesons with a transverse momentum of less than 10 GeV/c in the rapidity range $2.0 < y < 4.5$. The production cross-section is measured to be $15.2 \pm 1.0 \pm 0.9$ nb. The first uncertainty is statistical, and the second is systematic. The differential cross-sections as functions of several kinematic variables of the $J/\psi$ pair are measured and compared to theoretical predictions
Comments on Black Holes in Bubbling Spacetimes

In five-dimensional minimal supergravity, there are spherical black holes
with nontrivial topology outside the horizon which have the same conserved
charges at infinity as the BMPV solution. We show that some of these black
holes have greater entropy than the BMPV solution. These spacetimes are all
asymptotically flat, stationary, and supersymmetric. We also show that there is
a limit in which the black hole shrinks to zero size and the solution becomes a
nonsingular "bubbling" geometry. Thus, these solutions provide explicit
analytic examples of placing black holes inside solitons.Comment: 17 pages, 5 figures; v2: references adde
Baikov-Lee Representations Of Cut Feynman Integrals

We develop a general framework for the evaluation of $d$-dimensional cut
Feynman integrals based on the Baikov-Lee representation of purely-virtual
Feynman integrals. We implement the generalized Cutkosky cutting rule using
Cauchy's residue theorem and identify a set of constraints which determine the
integration domain. The method applies equally well to Feynman integrals with a
unitarity cut in a single kinematic channel and to maximally-cut Feynman
integrals. Our cut Baikov-Lee representation reproduces the expected relation
between cuts and discontinuities in a given kinematic channel and furthermore
makes the dependence on the kinematic variables manifest from the beginning. By
combining the Baikov-Lee representation of maximally-cut Feynman integrals and
the properties of periods of algebraic curves, we are able to obtain complete
solution sets for the homogeneous differential equations satisfied by Feynman
integrals which go beyond multiple polylogarithms. We apply our formalism to
the direct evaluation of a number of interesting cut Feynman integrals.Comment: 37 pages; v2 is the published version of this work with references
  added relative to v
Phenomenology of relaxion-Higgs mixing

We show that the relaxion generically stops its rolling at a point that
breaks CP leading to relaxion-Higgs mixing. This opens the door to a variety of
observational probes since the possible relaxion mass spans a broad range from
sub-eV to the GeV scale. We derive constraints from current experiments (fifth
force, astrophysical and cosmological probes, beam dump, flavour, LEP and LHC)
and present projections from future experiments such as NA62, SHiP and PIXIE.
We find that a large region of the parameter space is already under the
experimental scrutiny. All the experimental constraints we derive are equally
applicable for general Higgs portal models. In addition, we show that simple
multiaxion (clockwork) UV completions suffer from a mild fine tuning problem,
which increases with the number of sites. These results favour a cut-off scale
lower than the existing theoretical bounds.Comment: 46 pages, 6 figures, v3: typos fixed, references added, version
  matches the version published in JHE
One loop amplitude from null string

We generalize the CHY formalism to one-loop level, based on the framework of
the null string theory. The null string, a tensionless string theory, produces
the same results as the ones from the chiral ambitwistor string theory, with
the latter believed to give a string interpretation of the CHY formalism. A key
feature of our formalism is the interpretation of the modular parameters. We
find that the $S$ modular transformation invariance of the ordinary string
theory does not survive in the case of the null string theory. Treating the
integration over the modular parameters this way enable us to derive the n-gons
scattering amplitude in field theory, thus proving the n-gons conjecture.Comment: 18 pages, 2 figure
Nonlinear ${\cal N}=2$ Global Supersymmetry

We study the partial breaking of ${\cal N}=2$ global supersymmetry, using a
novel formalism that allows for the off-shell nonlinear realization of the
broken supersymmetry, extending previous results scattered in the literature.
We focus on the Goldstone degrees of freedom of a massive ${\cal N}=1$
gravitino multiplet which are described by deformed ${\cal N}=2$ vector and
single-tensor superfields satisfying nilpotent constraints. We derive the
corresponding actions and study the interactions of the superfields involved,
as well as constraints describing incomplete ${\cal N}=2$ matter multiplets of
non-linear supersymmetry (vectors and single-tensors)
Magnetoresistance in relativistic hydrodynamics without anomalies

We present expressions for the magnetoconductivity and the magnetoresistance
of a strongly interacting metal in 3+1 dimensions, derivable from relativistic
hydrodynamics. Such an approach is suitable for ultraclean metals with emergent
Lorentz invariance. When this relativistic fluid contains chiral anomalies, it
is known to exhibit longitudinal negative magnetoresistance. We show that
similar effects can arise in non-anomalous relativistic fluids due to the
distinctive gradient expansion. In contrast with a Galilean-invariant fluid,
the resistivity tensor of a dirty relativistic fluid exhibits similar angular
dependence to negative magnetoresistance, even when the constitutive relations
and momentum relaxation rate are isotropic. We further account for the effect
of magnetic field-dependent corrections to the gradient expansion and the
effects of long-wavelength impurities on magnetoresistance. We note that the
holographic D3/D7 system exhibits negative magnetoresistance.Comment: 18 page
Refined Counting of Necklaces in One-loop $\mathcal{N}=4$ SYM

We compute the grand partition function of $\mathcal{N}=4$ SYM at one-loop in
the $SU(2)$ sector with general chemical potentials, extending the results of
P\'olya's theorem. We make use of finite group theory, applicable to all orders
of $1/N_c$ expansion. We show that only the planar terms contribute to the
grand partition function, which is therefore equal to the grand partition
function of an ensemble of XXX$_\frac12$ spin chains. We discuss how Hagedorn
temperature changes on the complex plane of chemical potentials.Comment: 34 pages, v2: typo corrected, v3: added a subsection about finite Nc,
  to appear in JHE
Surveying 4d SCFTs twisted on Riemann surfaces

Within the framework of four dimensional conformal supergravity we consider
$\mathcal{N}=1,2,3,4$ supersymmetric theories generally twisted along the
abelian subgroups of the R-symmetry and possibly other global symmetry groups.
Upon compactification on constant curvature Riemann surfaces with arbitrary
genus we provide an extensive classification of the resulting two dimensional
theories according to the amount of supersymmetry that is preserved. Exploiting
the c-extremization prescription introduced in arXiv:1211.4030 we develop a
general procedure to obtain the central charge for 2d $\mathcal{N}=(0,2)$
theories and the expression of the corresponding R-current in terms of the
original 4d one and its mixing with the other abelian global currents.Comment: 31 pages, references added, typos fixed and improved discussion
Indirect searches of Galactic diffuse dark matter in INO-MagICAL
  detector

The signatures for the existence of dark matter are revealed only through its
gravitational interaction. Theoretical arguments support that the Weakly
Interacting Massive Particle (WIMP) can be a class of dark matter and it can
annihilate and/or decay to Standard Model particles, among which neutrino is a
favorable candidate. We show that the proposed 50 kt Magnetized Iron
CALorimeter (MagICAL) detector under the India-based Neutrino Observatory (INO)
project can play an important role in the indirect searches of Galactic diffuse
dark matter in the neutrino and antineutrino mode separately. We present the
sensitivity of 500 kt$\cdot$yr MagICAL detector to set limits on the
velocity-averaged self-annihilation cross-section ($\langle\sigma v\rangle$)
and decay lifetime ($\tau$) of dark matter having mass in the range of 2 GeV
$\leq m_\chi \leq $ 90 GeV and 4 GeV $\leq m_\chi \leq $ 180 GeV respectively,
assuming no excess over the conventional atmospheric neutrino and antineutrino
fluxes at the INO site. Our limits for low mass dark matter constrain the
parameter space which has not been explored before. We show that MagICAL will
be able to set competitive constraints, $\langle\sigma v\rangle\leq
1.87\,\times\,10^{-24}$ cm$^3$ s$^{-1}$ for $\chi\chi\rightarrow\nu\bar\nu$ and
$\tau\geq 4.8\,\times\,10^{24}$ s for $\chi\rightarrow\nu\bar\nu$ at 90$\%$
C.L. (1 d.o.f.) for $m_\chi$ = 10 GeV assuming the NFW as dark matter density
profile.Comment: 28 pages, 22 pdf figures. Discussions & references added. Fig. 9
  replaced with new figure for better understanding. Accepted in JHE
From the octagon to the SFT vertex - gluing and multiple wrapping

We compare various ways of decomposing and decompactifying the string field
theory vertex and analyze the relations between them. We formulate axioms for
the octagon and show how it can be glued to reproduce the decompactified
pp-wave SFT vertex which in turn can be glued to recover the exact finite
volume pp-wave Neumann coefficients. The gluing is performed by resumming
multiple wrapping corrections. We observe important nontrivial contributions at
the multiple wrapping level which are crucial for obtaining the exact results.Comment: 25 pages, many small figure
Prescriptive Unitarity

We introduce a prescriptive approach to generalized unitarity, resulting in a
strictly-diagonal basis of loop integrands with coefficients given by
specifically-tailored residues in field theory. We illustrate the power of this
strategy in the case of planar, maximally supersymmetric Yang-Mills theory,
where we construct closed-form representations of all ($n$-point N$^k$MHV)
scattering amplitudes through three loops. The prescriptive approach contrasts
with the ordinary description of unitarity-based methods by avoiding any need
for linear algebra to determine integrand coefficients. We describe this
approach in general terms as it should have applications to many quantum field
theories, including those without planarity, supersymmetry, or massless spectra
defined in any number of dimensions.Comment: 59 pages, 129 figures, 2 table
A locally supersymmetric $SO(10,2)$ invariant action for $D=12$
  supergravity

We present an action for $N=1$ supergravity in $10+2$ dimensions, containing
the gauge fields of the $OSp(1|64)$ superalgebra, i.e. one-forms $B^{(n)}$ with
$n$=1,2,5,6,9,10 antisymmetric D=12 Lorentz indices and a Majorana gravitino
$\psi$. The vielbein and spin connection correspond to $B^{(1)}$ and $B^{(2)}$
respectively. The action is not gauge invariant under the full $OSp(1|64)$
superalgebra, but only under a subalgebra ${\tilde F}$ (containing the $F$
algebra $OSp(1|32)$), whose gauge fields are $B^{(2)}$, $B^{(6)}$, $B^{(10)}$
and the Weyl projected Majorana gravitino ${1 \over 2} (1+\Gamma_{13}) \psi$.
Supersymmetry transformations are therefore generated by a Majorana-Weyl
supercharge and, being part of a gauge superalgebra, close off-shell. The
action is simply $\int STr ({\bf R}^6 {\bf \Gamma})$ where ${\bf R}$ is the
$OSp(1|64)$ curvature supermatrix two-form, and ${\bf \Gamma}$ is a constant
supermatrix involving $\Gamma_{13}$ and breaking $OSp(1|64)$ to its ${\tilde
F}$ subalgebra. The action includes the usual Einstein-Hilbert term.Comment: LaTeX, 13 pages. Added a reference, a Table in Appendix A for the
  gamma commutations in d=12, and corrected eq. (4.14) for the Einstein-Hilbert
  term; v4: corrected formulas (A.3), (A.4) and (A.10), modified last paragraph
  of Section 5, added acknowledgement
Perturbative corrections to $B \to D$ form factors in QCD

We compute perturbative QCD corrections to $B \to D$ form factors at leading
power in $\Lambda/m_b$, at large hadronic recoil, from the light-cone sum rules
(LCSR) with $B$-meson distribution amplitudes in HQET. QCD factorization for
the vacuum-to-$B$-meson correlation function with an interpolating current for
the $D$-meson is demonstrated explicitly at one loop with the power counting
scheme $m_c \sim {\cal O} \left (\sqrt{\Lambda \, m_b} \right ) $. The jet
functions encoding information of the hard-collinear dynamics in the
above-mentioned correlation function are complicated by the appearance of an
additional hard-collinear scale $m_c$, compared to the counterparts entering
the factorization formula of the vacuum-to-$B$-meson correction function for
the construction of $B \to \pi$ from factors. Inspecting the
next-to-leading-logarithmic sum rules for the form factors of $B \to D \ell
\nu$ indicates that perturbative corrections to the hard-collinear functions
are more profound than that for the hard functions, with the default theory
inputs, in the physical kinematic region. We further compute the subleading
power correction induced by the three-particle quark-gluon distribution
amplitudes of the $B$-meson at tree level employing the background gluon field
approach. The LCSR predictions for the semileptonic $B \to D \ell \nu$ form
factors are then extrapolated to the entire kinematic region with the
$z$-series parametrization. Phenomenological implications of our determinations
for the form factors $f_{BD}^{+, 0}(q^2)$ are explored by investigating the
(differential) branching fractions and the $R(D)$ ratio of $B \to D \ell \nu$
and by determining the CKM matrix element $|V_{cb}|$ from the total decay rate
of $B \to D \mu \nu_{\mu}$.Comment: 49 pages, 8 figures, version accepted for publication in JHE
Heat kernel methods for Lifshitz theories

We study the one-loop covariant effective action of Lifshitz theories using
the heat kernel technique. The characteristic feature of Lifshitz theories is
an anisotropic scaling between space and time. This is enforced by the
existence of a preferred foliation of space-time, which breaks Lorentz
invariance. In contrast to the relativistic case, covariant Lifshitz theories
are only invariant under diffeomorphisms preserving the foliation structure. We
develop a systematic method to reduce the calculation of the effective action
for a generic Lifshitz operator to an algorithm acting on known results for
relativistic operators. In addition, we present techniques that drastically
simplify the calculation for operators with special properties. We demonstrate
the efficiency of these methods by explicit applications.Comment: 36 pages, matches journal versio
A new formulation of Lee-Wick quantum field theory

The Lee-Wick models are higher-derivative theories that are claimed to be
unitary thanks to a peculiar cancelation mechanism. In this paper, we provide a
new formulation of the models, to clarify several aspects that have remained
quite mysterious, so far. Specifically, we define them as nonanalytically Wick
rotated Euclidean theories. The complex energy plane is divided into
disconnected regions, which can be related to one another by a well-defined,
albeit nonanalytic procedure. Working in a generic Lorentz frame, the models
are intrinsically equipped with the right recipe to treat the pinchings of the
Lee-Wick poles, with no need of external ad hoc prescriptions. We describe
these features in detail by calculating the one-loop bubble diagram and
explaining how the key properties generalize to more complicated diagrams. The
physical results of our formulation are different from those of the previous
ones. The unusual behaviors of the physical amplitudes lead to interesting
phenomenological predictions.Comment: 27 pages, 17 figures; v2: details about Lorentz invariance above LW
  thresholds; v3: minor changes, JHE
Elliptic Genera of 2d (0,2) Gauge Theories from Brane Brick Models

We compute the elliptic genus of abelian 2d (0,2) gauge theories
corresponding to brane brick models. These theories are worldvolume theories on
a single D1-brane probing a toric Calabi-Yau 4-fold singularity. We identify a
match with the elliptic genus of the non-linear sigma model on the same
Calabi-Yau background, which is computed using a new localization formula. The
matching implies that the quantum effects do not drastically alter the
correspondence between the geometry and the 2d (0,2) gauge theory. In theories
whose matter sector suffers from abelian gauge anomaly, we propose an ansatz
for an anomaly cancelling term in the integral formula for the elliptic genus.
We provide an example in which two brane brick models related to each other by
Gadde-Gukov-Putrov triality give the same elliptic genus.Comment: 56 pages, 15 figures; v2. references added; v3. a reference and a
  comment on a fixed point index theorem adde
Schwinger-Keldysh formalism I: BRST symmetries and superspace

We review the Schwinger-Keldysh, or in-in, formalism for studying quantum
dynamics of systems out-of-equilibrium. The main motivation is to rephrase well
known facts in the subject in a mathematically elegant setting, by exhibiting a
set of BRST symmetries inherent in the construction. We show how these
fundamental symmetries can be made manifest by working in a superspace
formalism. We argue that this rephrasing is extremely efficacious in
understanding low energy dynamics following the usual renormalization group
approach, for the BRST symmetries are robust under integrating out degrees of
freedom. In addition we discuss potential generalizations of the formalism that
allow us to compute out-of-time-order correlation functions that have been the
focus of recent attention in the context of chaos and scrambling. We also
outline a set of problems ranging from stochastic dynamics, hydrodynamics,
dynamics of entanglement in QFTs, and the physics of black holes and cosmology,
where we believe this framework could play a crucial role in demystifying
various confusions. Our companion paper arXiv:1610.01941 describes in greater
detail the mathematical framework embodying the topological symmetries we
uncover here.Comment: 94 pages; v2: fixed typos. v3: minor clarifications and improvements.
  v4: further minor improvements. published versio
Schwinger-Keldysh formalism II: Thermal equivariant cohomology

Causally ordered correlation functions of local operators in near-thermal
quantum systems computed using the Schwinger-Keldysh formalism obey a set of
Ward identities. These can be understood rather simply as the consequence of a
topological (BRST) algebra, called the universal Schwinger-Keldysh
superalgebra, as explained in our companion paper arXiv:1610.01940. In the
present paper we provide a mathematical discussion of this topological algebra.
In particular, we argue that the structures can be understood in the language
of extended equivariant cohomology. To keep the discussion self-contained, we
provide a basic review of the algebraic construction of equivariant cohomology
and explain how it can be understood in familiar terms as a superspace gauge
algebra. We demonstrate how the Schwinger-Keldysh construction can be
succinctly encoded in terms a thermal equivariant cohomology algebra which
naturally acts on the operator (super)-algebra of the quantum system. The main
rationale behind this exploration is to extract symmetry statements which are
robust under renormalization group flow and can hence be used to understand
low-energy effective field theory of near-thermal physics. To illustrate the
general principles, we focus on Langevin dynamics of a Brownian particle,
rephrasing some known results in terms of thermal equivariant cohomology. As
described elsewhere, the general framework enables construction of effective
actions for dissipative hydrodynamics and could potentially illumine our
understanding of black holes.Comment: 72 pages; v2: fixed typos. v3: minor clarifications and improvements
  to non-equilbirum work relations discussion. v4: typos fixed. published
  versio
Flux Flattening in Axion Monodromy Inflation

String theory models of axion monodromy inflation exhibit scalar potentials
which are quadratic for small values of the inflaton field and evolve to a more
complicated function for large field values. Oftentimes the large field
behaviour is gentler than quadratic, lowering the tensor-to-scalar ratio. This
effect, known as flattening, has been observed in the string theory context
through the properties of the DBI+CS D-brane action. We revisit such flattening
effects in type IIB flux compactifications with mobile D7-branes, with the
inflaton identified with the D7-brane position. We observe that, with a generic
choice of background fluxes, flattening effects are larger than previously
observed, allowing to fit these models within current experimental bounds. In
particular, we compute the cosmological observables in scenarios compatible
with closed-string moduli stabilisation, finding tensor-to-scalar ratios as low
as r ~ 0.04. These are models of single field inflation in which the inflaton
is much lighter than the other scalars through a mild tuning of the
compactification data.Comment: 56 pages, 11 plot
Exact Deconstruction of the 6D (2,0) Theory

The dimensional-deconstruction prescription of Arkani-Hamed, Cohen, Kaplan,
Karch and Motl provides a mechanism for recovering the $A$-type (2,0) theories
on $T^2$, starting from a four-dimensional $\mathcal N=2$ circular-quiver
theory. We put this conjecture to the test using two exact-counting arguments:
In the decompactification limit, we compare the Higgs-branch Hilbert series of
the 4D $\mathcal N=2$ quiver to the "half-BPS" limit of the (2,0)
superconformal index. We also compare the full partition function for the 4D
quiver on $S^4$ to the (2,0) partition function on $S^4 \times T^2$. In both
cases we find exact agreement. The partition function calculation sets up a
dictionary between exact results in 4D and 6D.Comment: 49 pages; v2 typos corrected, published versio