pinecone/core-2020-05-10-deduplication huggingface dataset:
Vacuum polarization of STU black holes and their subtracted geometry limit

We study the vacuum polarization of a massless minimally coupled scalar field at the horizon of four-charge STU black holes. We compare the results for the standard asymptotically flat black holes and for the black holes obtained in the “subtracted limit”, both in the general static case and at the horizon pole for the general rotating case. The original and the subtracted results are identical only in the BPS limit, and have opposite sign in the extremal Kerr limit. We also compute the vacuum polarization on the static solutions that interpolate between both the original and the subtracted case through a solution-generating transformation and show that the vacuum polarization stays positive throughout the interpolating solution. In the appendix we provide a closed-form solution for the Green’s function on general (static or rotating) subtracted black hole geometries
Consistent Kaluza-Klein truncations via exceptional field theory

We present the generalized Scherk-Schwarz reduction ansatz for the full supersymmetric exceptional field theory in terms of group valued twist matrices subject to consistency equations. With this ansatz the field equations precisely reduce to those of lower-dimensional gauged supergravity parametrized by an embedding tensor. We explicitly construct a family of twist matrices as solutions of the consistency equations. They induce gauged supergravities with gauge groups SO( p, q ) and CSO( p, q, r ). Geometrically, they describe compactifications on internal spaces given by spheres and (warped) hyperboloides H p,q , thus extending the applicability of generalized Scherk-Schwarz reductions beyond homogeneous spaces. Together with the dictionary that relates exceptional field theory to D = 11 and IIB supergravity, respectively, the construction defines an entire new family of consistent truncations of the original theories. These include not only compactifications on spheres of different dimensions (such as AdS 5 × S 5 ), but also various hyperboloid compactifications giving rise to a higher-dimensional embedding of supergravities with non-compact and non-semisimple gauge groups
Instanton-mediated baryon number violation in non-universal gauge extended models

Instanton solutions of non-abelian Yang-Mills theories generate an effective action that may induce lepton and baryon number violations, namely Δ B = Δ L = n f , being n f the number of families coupled to the gauge group. In this article we study instanton mediated processes in a SU(2) ℓ ⊗SU(2) h ⊗U(1) extension of the Standard Model that breaks universality by singularizing the third family. In the construction of the instanton Green functions we account systematically for the inter-family mixing. This allows us to use the experimental bounds on proton decay in order to constrain the gauge coupling of SU(2) h . Tau lepton non-leptonic and radiative decays with Δ B = Δ L = 1 are also analysed
Gauge theories and dessins d’enfants: beyond the torus

Dessin d ’ enfants on elliptic curves are a powerful way of encoding doubly-periodic brane tilings, and thus, of four-dimensional supersymmetric gauge theories whose vacuum moduli space is toric, providing an interesting interplay between physics, geometry, combinatorics and number theory. We discuss and provide a partial classification of the situation in genera other than one by computing explicit Belyi pairs associated to the gauge theories. Important also is the role of the Igusa and Shioda invariants that generalise the elliptic j -invariant
Sgoldstino-Higgs mixing in models with low-scale supersymmetry breaking

We consider a supersymmetric extension of the Standard Model with low-scale supersymmetry breaking. Besides usual superpartners it contains additional chiral goldstino supermultiplet whose scalar components — sgoldstinos — can mix with scalars from the Higgs sector of the model. We show that this mixing can have considerable impact on phenomenology of the lightest Higgs boson and scalar sgoldstino. In particular, the latter can be a good candidate for explanation of 2 σ LEP excess with mass around 98 GeV
The a -function for gauge theories

The a -function is a proposed quantity defined for quantum field theories which has a monotonic behaviour along renormalisation group flows, being related to the β -functions via a gradient flow equation involving a positive definite metric. We construct the a -function at four-loop order for a general gauge theory with fermions and scalars, using only one and two loop β -functions; we are then able to provide a stringent consistency check on the general three-loop gauge β -function. In the case of an N = 1 $$ \mathcal{N}=1 $$ supersymmetric gauge theory, we present a general condition on the chiral field anomalous dimension which guarantees an exact all-orders expression for the a -function; and we verify this up to fifth order (corresponding to the three-loop anomalous dimension)
Foliated eight-manifolds for M-theory compactification

We characterize compact eight-manifolds M which arise as internal spaces in N = 1 $$ \mathcal{N}=1 $$ flux compactifications of M-theory down to AdS 3 using the theory of foliations, for the case when the internal part ξ of the supersymmetry generator is everywhere non-chiral. We prove that specifying such a supersymmetric background is equivalent with giving a codimension one foliation ℱ $$ \mathrm{\mathcal{F}} $$ of M which carries a leafwise G 2 structure, such that the O’Neill-Gray tensors, non-adapted part of the normal connection and the torsion classes of the G 2 structure are given in terms of the supergravity four-form field strength by explicit formulas which we derive. We discuss the topology of such foliations, showing that the C * algebra C M / ℱ $$ C\left(M/\mathrm{\mathcal{F}}\right) $$ is a noncommutative torus of dimension given by the irrationality rank of a certain cohomology class constructed from G , which must satisfy the Latour obstruction. We also give a criterion in terms of this class for when such foliations are fibrations over the circle. When the criterion is not satisfied, each leaf of ℱ $$ \mathrm{\mathcal{F}} $$ is dense in M
Medium-induced soft gluon radiation in forward dijet production in relativistic proton-nucleus collisions

Considering forward dijet production in the q → qg partonic process, we derive the spectrum of accompanying soft gluon radiation induced by rescatterings in a nuclear target. The spectrum is obtained to logarithmic accuracy for an arbitrary energy sharing between the final quark and gluon, and for final transverse momenta as well as momentum imbalance being large as compared to transverse momentum nuclear broadening. In the case of equal energy sharing and for approximately back-to-back quark and gluon transverse momenta, we reproduce a previous result of Liou and Mueller. Interpreting our result, we conjecture a simple formula for the medium-induced radiation spectrum associated to hard forward 1 → n processes, which we explicitly check in the case of the g → gg process
Cosmological Phase Transitions and their Properties in the NMSSM

We study cosmological phase transitions in the Next-to-Minimal Supersymmetric
Standard Model (NMSSM) in light of the Higgs discovery. We use an effective
field theory approach to calculate the finite temperature effective potential,
focusing on regions with significant tree-level contributions to the Higgs
mass, a viable neutralino dark matter candidate, 1-2 TeV stops, and with the
remaining particle spectrum compatible with current LHC searches and results.
The phase transition structure in viable regions of parameter space exhibits a
rich phenomenology, potentially giving rise to one- or two-step first-order
phase transitions in the singlet and/or $SU(2)$ directions. We compute several
parameters pertaining to the bubble wall profile, including the bubble wall
width and $\Delta\beta$ (the variation of the ratio in Higgs vacuum expectation
values across the wall). These quantities can vary significantly across small
regions of parameter space and can be promising for successful electroweak
baryogenesis. We estimate the wall velocity microphysically, taking into
account the various sources of friction acting on the expanding bubble wall.
Ultra-relativistic solutions to the bubble wall equations of motion typically
exist when the electroweak phase transition features substantial supercooling.
For somewhat weaker transitions, the bubble wall instead tends to be
sub-luminal and, in fact, likely sub-sonic, suggesting that successful
electroweak baryogenesis may indeed occur in regions of the NMSSM compatible
with the Higgs discovery.Comment: 49 pages + 2 appendices, 6 figures. v2: Minor corrections; matches
  version published in JHE
Generalized superconductors and holographic optics. Part II

Using linear response theory, we analyze the electromagnetic response functions of generalized holographic superconductors, in AdS-Schwarzschild and single R-charged black hole backgrounds in four dimensions. By introducing momentum dependent vector mode perturbations, the response functions for these systems are studied numerically, including the effects of backreaction. This complements and completes the probe limit analysis for these backgrounds initiated in our previous work ( arXiv:1305.6273 ). Our numerical analysis indicates a negative Depine-Lakhtakia index for both the backgrounds studied, at low enough frequencies. The dependence of the response functions on the backreaction parameter and the model parameters are established and analyzed with respect to similar backgrounds in five dimensions
Flat space (higher spin) gravity with chemical potentials

We introduce flat space spin-3 gravity in the presence of chemical potentials and discuss some applications to flat space cosmology solutions, their entropy, free energy and flat space orbifold singularity resolution. Our results include flat space Einstein gravity with chemical potentials as special case. We discover novel types of phase transitions between flat space cosmologies with spin-3 hair and show that the branch that continuously connects to spin-2 gravity becomes thermodynamically unstable for sufficiently large temperature or spin-3 chemical potential
Gluino mass limits with sbottom NLSP in coannihilation scenarios

In view of the recent interest in the pMSSM with light third generation squarks, we consider a hitherto neglected scenario where the lighter bottom squark b ˜ 1 $$ \left({\tilde{b}}_1\right) $$ is the next lightest supersymmetric particle (NLSP) which co-annihilates with the lightest supersymmetric particle (LSP), the dark matter (DM) candidate. Since the co-annihilation cross section receives contributions from both electroweak and strong vertices, it is relatively large. As a result relatively large NLSP-LSP mass difference (25-35 GeV) is consistent with the PLANCK data. This facilitates the LHC signatures of this scenario. We consider several variants of the sbottom NLSP scenario with and without light stops and delineate the parameter space allowed by the PLANCK data. We point out several novel signal (e.g., t ˜ 1 → b ˜ 1 W $$ {\tilde{t}}_1\to {\tilde{b}}_1W $$ ) which are not viable in the stop NLSP scenario of DM production. Finally, we consider gluino g ˜ $$ \left(\tilde{g}\right) $$ decays in this scenario and using the current ATLAS data in the jets (with or without b-tagging) + channel, obtain new limits in the m b ˜ 1 − m g ˜ $$ {m}_{{\tilde{b}}_1}-{m}_{\tilde{g}} $$ mass plane. We find that for m b ˜ 1 $$ {m}_{\tilde{b}1} $$ upto 500 GeV, m g ˜ $$ {m}_{\tilde{g}} $$ ≥ 1.1-1.2 TeV in this scenario
Angular analysis of the decay Λ b → Λ(→ Nπ ) ℓ + ℓ −

We study the differential decay rate for the rare Λ b → Λ(→ N π) ℓ + ℓ − transition, including a determination of the complete angular distribution, assuming unpolarized Λ b baryons. On the basis of a properly chosen parametrization of the various helicity amplitudes, we provide expressions for the angular observables within the Standard Model and a subset of new physics models with chirality-flipped operators. Hadronic effects at low recoil are estimated by combining information from lattice QCD with (improved) form-factor relations in Heavy Quark Effective Theory. Our estimates for large hadronic recoil — at this stage — are still rather uncertain because the baryonic input functions are not so well known, and non-factorizable spectator effects have not been worked out systematically so far. Still, our phenomenological analysis of decay asymmetries and angular observables for Λ b → Λ(→ Nπ ) ℓ + ℓ − reveals that this decay mode can provide new and complementary constraints on the Wilson coefficients in radiative and semileptonic b → s transitions compared to the corresponding mesonic modes
Dynamical generation of the weak and Dark Matter scales from strong interactions

Assuming that mass scales arise in nature only via dimensional transmutation, we extend the dimension-less Standard Model by adding vector-like fermions charged under a new strong gauge interaction. Their non-perturbative dynamics generates a mass scale that is transmitted to the elementary Higgs boson by electro-weak gauge interactions. In its minimal version the model has the same number of parameters as the Standard Model, predicts that the electro-weak symmetry gets broken, predicts new-physics in the multi-TeV region and is compatible with all existing bounds, provides two Dark Matter candidates stable thanks to accidental symmetries: a composite scalar in the adjoint of SU(2) L and a composite singlet fermion; their thermal relic abundance is predicted to be comparable to the measured cosmological DM abundance. Some models of this type allow for extra Yukawa couplings; DM candidates remain even if explicit masses are added
Sparticle mass hierarchies, simplified models from SUGRA unification, and benchmarks for LHC Run-II SUSY searches

Sparticle mass hierarchies contain significant information regarding the origin and nature of supersymmetry breaking. The hierarchical patterns are severely constrained by electroweak symmetry breaking as well as by the astrophysical and particle physics data. They are further constrained by the Higgs boson mass measurement. The sparticle mass hierarchies can be used to generate simplified models consistent with the high scale models. In this work we consider supergravity models with universal boundary conditions for soft parameters at the unification scale as well as supergravity models with nonuniversalities and delineate the list of sparticle mass hierarchies for the five lightest sparticles. Simplified models can be obtained by a truncation of these, retaining a smaller set of lightest particles. The mass hierarchies and their truncated versions enlarge significantly the list of simplified models currently being used in the literature. Benchmarks for a variety of supergravity unified models appropriate for SUSY searches at future colliders are also presented. The signature analysis of two benchmark models has been carried out and a discussion of the searches needed for their discovery at LHC Run-II is given. An analysis of the spin-independent neutralino-proton cross section exhibiting the Higgs boson mass dependence and the hierarchical patterns is also carried out. It is seen that a knowledge of the spin-independent neutralino-proton cross section and the neutralino mass will narrow down the list of the allowed sparticle mass hierarchies. Thus dark matter experiments along with analyses for the LHC Run-II will provide strong clues to the nature of symmetry breaking at the unification scale
Can A Pseudo-Nambu-Goldstone Higgs Lead To Symmetry Non-Restoration?

The calculation of finite temperature contributions to the scalar potential
in a quantum field theory is similar to the calculation of loop corrections at
zero temperature. In natural extensions of the Standard Model where loop
corrections to the Higgs potential cancel between Standard Model degrees of
freedom and their symmetry partners, it is interesting to contemplate whether
finite temperature corrections also cancel, raising the question of whether a
broken phase of electroweak symmetry may persist at high temperature. It is
well known that this does not happen in supersymmetric theories because the
thermal contributions of bosons and fermions do not cancel each other. However,
for theories with same spin partners, the answer is less obvious. Using the
Twin Higgs model as a benchmark, we show that although thermal corrections do
cancel at the level of quadratic divergences, subleading corrections still
drive the system to a restored phase. We further argue that our conclusions
generalize to other well-known extensions of the Standard Model where the Higgs
is rendered natural by being the pseudo-Nambu-Goldstone mode of an approximate
global symmetry.Comment: 21 pages, 5 figures. v2: fixed problem related to references with
  9-digit arXiv identifiers. v3: references added v4: Some clarifications and
  more references added; matches published versio
Partially-massless higher-spin algebras and their finite-dimensional
  truncations

The global symmetry algebras of partially-massless (PM) higher-spin (HS)
fields in (A)dS$_{d+1}$ are studied. The algebras involving PM generators up to
depth $2\,(\ell-1)$ are defined as the maximal symmetries of free conformal
scalar field with $2\,\ell$ order wave equation in $d$ dimensions. We review
the construction of these algebras by quotienting certain ideals in the
universal enveloping algebra of $(A)dS_{d+1}$ isometries. We discuss another
description in terms of Howe duality and derive the formula for computing trace
in these algebras. This enables us to explicitly calculate the bilinear form
for this one-parameter family of algebras. In particular, the bilinear form
shows the appearance of additional ideal for any non-negative integer values of
$\ell-d/2\,$, which coincides with the annihilator of the one-row $\ell$-box
Young diagram representation of $\mathfrak{so}_{d+2}\,$. Hence, the
corresponding finite-dimensional coset algebra spanned by massless and PM
generators is equivalent to the symmetries of this representation.Comment: 22 pages, references added, revised version, accepted to JHE
Neutrino Physics with Accelerator Driven Subcritical Reactors

Accelerator driven system (ADS) subcritical nuclear reactors are under
development around the world. They will be intense sources of free, 30-50 MeV
antimuon decay at rest antimuon neutrinos. These ADS reactor neutrinos can
provide a robust test of the LSND anomaly and a precise measurement of the
leptonic CP-violating phase delta, including sign(cos(delta)). The first phase
of many ADS programs includes the construction of a low energy, high intensity
proton or deuteron accelerator, which can yield competitive bounds on sterile
neutrinos.Comment: 5 pages, 4 pdf figures, v2 more backgrounds included, typos fixe
On 2d Conformal Field Theories with Two Characters

Rational CFT's are classified by an integer $\ell$, the number of zeroes of
the Wronskian of their characters in moduli space. For $\ell=0$ they satisfy
non-singular modular-invariant differential equations, while for $\ell>0$ the
corresponding equations have singularities. We survey CFT's with two characters
and $\ell=0,2,3,4$ and verify the consistency, at the level of characters, of
some candidate theories with $\ell\ne 0$. For $\ell=2$ there are seven
consistents sets of characters. We identify specific combinations of level-1
current algebras that are potential symmetries of the corresponding CFT's.Comment: 29 pages, expanded with discussion on chiral algebras, final version
  to appear in JHE
Warped flavor symmetry predictions for neutrino physics

A realistic five-dimensional warped scenario with all standard model fields
propagating in the bulk is proposed. Mass hierarchies would in principle be
accounted for by judicious choices of the bulk mass parameters, while fermion
mixing angles are restricted by a $\Delta(27)$ flavor symmetry broken on the
branes by flavon fields. The latter gives stringent predictions for the
neutrino mixing parameters, and the Dirac CP violation phase, all described in
terms of only two independent parameters at leading order. The scheme also
gives an adequate CKM fit and should be testable within upcoming oscillation
experiments.Comment: 19 pages, 2 figue
Violations of the Born rule in cool state-dependent horizons

The black hole information problem has motivated many proposals for new
physics. One idea, known as state-dependence, is that quantum mechanics must be
generalized to describe the physics of black holes, and that fixed linear
operators do not provide the fundamental description of experiences for
infalling observers. Instead, such experiences are to be described by operators
with an extra dependence on the global quantum state. We show that any
implementation of this idea strong enough to remove firewalls from generic
states requires massive violations of the Born rule. We also demonstrate a
sense in which such violations are visible to infalling observers involved in
preparing the initial state of the black hole. We emphasize the generality of
our results; no details of any specific proposal for state-dependence are
required.Comment: 20 pages, 1 figure. v2: references adde
F-Theory, Spinning Black Holes and Multi-string Branches

We study 5d supersymmetric black holes which descend from strings of generic
$\mathcal{N}=(1,0)$ supergravity in 6d. These strings have an F-theory
realization in 6d as D3 branes wrapping smooth genus $g$ curves in the base of
elliptic 3-folds. They enjoy $(0,4)$ worldsheet supersymmetry with an extra
$SU(2)_L$ current algebra at level $g$ realized on the left-movers. When the
smooth curves degenerate they lead to multi-string branches and we find that
the microscopic worldsheet theory flows in the IR to disconnected 2d CFTs
having different central charges. The single string sector is the one with
maximal central charge, which when wrapped on a circle, leads to a 5d spinning
BPS black hole whose horizon volume agrees with the leading entropy prediction
from the Cardy formula. However, we find new phenomena where this branch meets
other branches of the CFT. These include multi-string configurations which have
no bound states in 6 dimensions but are bound through KK momenta when wrapping
a circle, as well as loci where the curves degenerate to spheres. These loci
lead to black hole configurations which can have total angular momentum
relative to a Taub-Nut center satisfying $J^2 > M^3$ and whose number of
states, though exponentially large, grows much slower than those of the large
spinning black hole.Comment: 60 pages, 9 figures. v3: meaning of "CCB violating states" clarified,
  typos corrected, acknowledgements adde
Nonstandard Yukawa Couplings and Higgs Portal Dark Matter

We study the implications of non-standard Higgs Yukawa couplings to light
quarks on Higgs-portal dark matter phenomenology. Saturating the present
experimental bounds on up-quark, down-quark, or strange-quark Yukawa couplings,
the predicted direct dark matter detection scattering rate can increase by up
to four orders of magnitude. The effect on the dark matter annihilation cross
section, on the other hand, is subleading unless the dark matter is very light
-- a scenario that is already excluded by measurements of the Higgs invisible
decay width. We investigate the expected size of corrections in
multi-Higgs-doublet models with natural flavor conservation, the type-II
two-Higgs-doublet model, the Giudice-Lebedev model of light quark masses,
minimal flavor violation new physics models, Randall-Sundrum, and composite
Higgs models. We find that an enhancement in the dark matter scattering rate of
an order of magnitude is possible. Finally, we point out that a discovery of
Higgs-portal dark matter could lead to interesting bounds on the light-quark
Yukawa couplings.Comment: 38 pages, 12 figures; minor mistake in numerics fixed, conclusions
  unchanged; references adde