pinecone/core-2020-05-10-deduplication huggingface dataset:
The hierarchion, a relaxion addressing the Standard Model’s hierarchies.

We present a mechanism that addresses the electroweak, the strong CP, and\ud
the flavor hierarchies of the Standard Model (including neutrino masses) in a unified way.\ud
The naturalness of the electroweak scale is solved together with the strong CP problem by\ud
the Nelson-Barr relaxion: the relaxion field is identified with the pseudo-Nambu-Goldstone\ud
boson of an abelian symmetry with no QCD anomaly. The Nelson-Barr sector generates\ud
the “rolling” potential and the relaxion vacuum expectation value at the stopping point is\ud
mapped to the Cabibbo-Kobayashi-Maskawa phase. The same abelian symmetry accounts\ud
for the Standard Model’s mass hierarchies and flavor textures through the Froggatt-Nielsen\ud
mechanism. We show how the “backreaction” potential of the relaxion can be induced by\ud
a sterile neutrino sector, without any extra state with electroweak quantum numbers. The\ud
same construction successfully explains neutrino masses and mixings. The only light field\ud
in our model is the relaxion, which we call the hierarchion because it is central to our\ud
construction that accounts for all the Standard Model hierarchies. Given its interplay with\ud
flavor symmetries, the hierarchion can be probed in flavor-violating decays of the Standard\ud
Model fermions, motivating a further experimental effort in looking for new physics in rare\ud
decays of leptons and mesons
Supersymmetric SYK Model with Global Symmetry

In this paper, we introduce an $\mathcal{N}=1$ supersymmetric SYK model with
$SO(q)$ global symmetry. We study the large $N$ expansion of the bi-local
collective action of our model. At strong coupling limit, this model exhibits a
super-reparametrization symmetry, and the $SO(q)$ global symmetry is enhanced
to a $\widehat{SO}(q)$ local symmetry. The corresponding symmetry algebra is
the semi-direct product of the super-Virasoro and the super-Kac-Moody algebras.
These emergent symmetries are spontaneously and explicitly broken, which leads
to a low energy effective action: super-Schwarzian action plus an action of a
super-particle on the $SO(q)$ group manifold. We analyze the zero mode
contributions to the chaotic behavior of four point functions in various
$SO(q)$ channels. In singlet channel, we show that the out-of-time-ordered
correlators related to bosonic bi-locals exhibit the saturation of the chaos
bound as in the non-SUSY SYK model. On the other hand, we find that the ones
with fermionic bi-locals in the singlet channel have ${\pi\over\beta}$ Lyapunov
exponent. In the anti-symmetric channel, we demonstrate that the
out-of-time-ordered correlator related to a $SO(q)$ generator grows linearly in
time. We also compute the non-zero mode contributions which give consistent
corrections to the leading Lyapunov exponents from the zero modes.Comment: 48 pages + Appendix, 1 figure and 2 table
Universal features of BPS strings in six-dimensional SCFTs.

In theories with extended supersymmetry the protected observables of UV superconformal fixed points are found in a number of contexts to be encoded in the BPS solitons along an IR Coulomb-like phase. For six-dimensional SCFTs such a role is played by the BPS strings on the tensorial Coulomb branch. In this paper we develop a uniform description of the worldsheet theories of a BPS string for rank-one 6d SCFTs. These strings are the basic constituents of the BPS string spectrum of arbitrary rank six-dimensional models, which they generate by forming bound states. Motivated by geometric engineering in F-theory, we describe the worldsheet theories of the BPS strings in terms of topologically twisted 4d   N=2  theories in the presence of 1/2-BPS 2d (0, 4) defects. As the superconformal point of a 6d theory with gauge group G is approached, the resulting worldsheet theory flows to an   N=(0, 4)  NLSM with target the moduli space of one G instanton, together with a nontrivial left moving bundle characterized by the matter content of the six-dimensional model. We compute the anomaly polynomial and central charges of the NLSM, and argue that the 6d flavor symmetry F is realized as a current algebra on the string, whose level we compute. We find evidence that for generic theories the G dependence is captured at the level of the elliptic genus by characters of an affine Kac-Moody algebra at negative level, which we interpret as a subsector of the chiral algebra of the BPS string worldsheet theory. We also find evidence for a spectral flow relating the R-R and NS-R elliptic genera. These properties of the string CFTs lead to constraints on their spectra, which in combination with modularity allow us to determine the elliptic genera of a vast number of string CFTs, leading also to novel results for 6d and 5d instanton partition functions
Causality of fluid dynamics for high-energy nuclear collisions

Dissipative relativistic fluid dynamics is not always causal and can favor
superluminal signal propagation under certain circumstances. On the other hand,
high-energy nuclear collisions have a microscopic description in terms of QCD
and are expected to follow the causality principle of special relativity. We
discuss under which conditions the fluid evolutions for a radial expansion are
hyperbolic and how the properties of the solutions are encoded in the
associated characteristic curves. The expansion dynamics is causal in
relativistic sense if the characteristic velocities are smaller than the speed
of light. We obtain a concrete inequality from this constraint and discuss how
it can be violated for certain initial conditions. We argue that causality
poses a bound to the applicability of relativistic fluid dynamics. }Comment: 23 pages, 13 figures; Added references, corrected typos, added
  discussion as section 2, results unchange
On Superconformal Four-Point Mellin Amplitudes in Dimension $d>2$

We present a universal treatment for imposing superconformal constraints on
Mellin amplitudes for $\mathrm{SCFT_d}$ with $3\leq d\leq 6$. This leads to a
new technique to compute holographic correlators, which is similar but
complementary to the ones introduced in [1,2]. We apply this technique to
theories in various spacetime dimensions. In addition to reproducing known
results, we obtain a simple expression for next-next-to-extremal four-point
functions in $AdS_7\times S^4$. We also use this machinery on $AdS_4\times S^7$
and compute the first holographic one-half BPS four-point function. We extract
the anomalous dimension of the R-symmetry singlet double-trace operator with
the lowest conformal dimension and find agreement with the 3d $\mathcal{N}=8$
numerical bootstrap bound at large central charge.Comment: 34 pages, 1 figure; v2: minor changes, typos corrected; v3: published
  versio
Holographic superfluids as duals of rotating black strings

We study the breaking of an Abelian symmetry close to the horizon of an
uncharged rotating Anti-de Sitter black string in 3+1 dimensions. The boundary
theory living on R^2 x S^1 has no rotation, but a magnetic field that is
aligned with the axis of the black string. This boundary theory decribes
non-rotating (2+1)-dimensional holographic superfluids with non-vanishing
superfluid velocity. We study these superfluids in the grand canonical ensemble
and show that for sufficiently small angular momentum of the dual black string
and sufficiently small superfluid velocity the phase transition is 2nd order,
while it becomes 1st order for larger superfluid velocity. Moreover, we observe
that the phase transition is always 1st order above a critical value of the
angular momentum independent of the choice of the superfluid velocity.Comment: 9 pages including 5 figures: v2: 12 pages including 7 figures; 2
  figures added, discussion on free energy added; accepted for publication in
  JHE
Supersymmetry Breaking Scalar Masses and Trilinear Soft Terms in
  Generalized Minimal Supergravity

In the generalized minimal supergravity (GmSUGRA) scenario, we systematically
study the supersymmetry breaking scalar masses, Standard Model fermion Yukawa
coupling terms, and trilinear soft terms in SU(5) models with the Higgs fields
in the {\bf 24} and {\bf 75} representations, and in SO(10) models where the
gauge symmetry is broken down to the Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R
gauge symmetry, SU(3)_C X SU(2)_L X SU(2)_R X U(1)_{B-L} gauge symmetry,
George-Glashow SU(5) X U(1)' gauge symmetry, flipped SU(5) X U(1)_X gauge
symmetry, and SU(3)_C X SU(2)_L X U(1)_1 X U(1)_2 gauge symmetry. Most
importantly, we for the first time consider the scalar and gaugino mass
relations, which can be preserved from the unification scale to the electroweak
scale under one-loop renormalization group equation running, in the SU(5)
models, the Pati-Salam models and flipped SU(5) X U(1)_X models arising from
SO(10) models. With such interesting relations, we may distinguish the minimal
supergravity (mSUGRA) and GmSUGRA scenarios if the supersymmetric particle
spectrum can be measured at the LHC and ILC. Thus, it provides us with another
important window of opportunity at the Planck scale.Comment: Latex, 33 pages, reference added, version to appear in JHE
1/2-BPS Wilson Loops and Vortices in ABJM Model

We explore the low-energy dynamics of 1/2-BPS heavy particles coupled to the
ABJM model via the Higgsing of M2-branes, with focus on physical understanding
of the recently discovered 1/2-BPS Wilson loop operators. The low-energy theory
of 1/2-BPS heavy particles turns out to have the U(N|N) supergauge symmetry,
which explains the novel structure of the 1/2-BPS Wilson loop operator as a
holonomy of a U(N|N) superconnection. We show that the supersymmetric
transformation of the Wilson loop operator can be identified as a fermionic
supergauge transformation, which leads to their invariance under half of the
supersymmetry. We also argue that 1/2-BPS Wilson loop operators appear as
1/2-BPS vortices with vorticity 1/k. Such a vortex can be naturally interpreted
as a membrane wrapping the Z_k cycle once, or type IIA fundamental string.Comment: 22 page
Particle production in DIS off a shockwave in AdS

Within the AdS/CFT correspondence, the shockwave metric has been widely used
as a gravity dual for a fast moving nucleus. Here we propose a picture for
particle production in deep inelastic scattering off a shockwave with the
projectile represented by the $\mathcal{R}$-current. By using the method
developed in \cite{Avsar:2009xf} to find an explicit expression for the
scattered field, we are able to show that the scattered field can be written in
terms of time-like and space-like vacuum states where the time-like states are
identified with the outgoing particles. To support this picture, we calculate
the contribution of the time-like modes to the energy-momentum tensor of the
scattered field and show that the energy flow in the fifth dimension is
directly related to the imaginary part of the action. The energy flow in the
fifth dimension is also compared to the incoming energy flow to determine which
fraction of the initial energy goes to the produced particles. The last two
sections are devoted to localize the energy flow in momentum and coordinate
space, first by finding the virtualities that contribute the most to the total
flow, and second by finding an approximate trajectory in coordinate space.Comment: 17 pages, 1 figure. Added references. To appear in JHE
Pure spinor computation towards open string three-loop

Using the recent results in the pure spinor formulation, we lay out a
ground-work towards the full momentum space amplitudes of open superstrings at
three-loop. After briefly reviewing the one-loop amplitude, we directly work
out the two-loop and reproduce the result that was obtained by a symmetry
argument. For the three-loop, first we use the two-loop regulator as a warm-up
exercise. The result vanishes. We then employ the regulator that has been
recently proposed by Aisaka and Berkovits (AB). It is noted that the terms in
higher power in $\frac{1}{\lambda\bar{\lambda}}$ that render the two-loop
regulator disqualified for the three-loop do not contribute. This with a few
other indications suggests a possibility that the AB regulator might also lead
to a vanishing result. Nevertheless, we argue that it is possible to acquire
the three-loop amplitude, and present a result that we anticipate to be the
three-loop amplitude.Comment: 41 pages, latex, cosmetic change
Counterterms in semiclassical Horava-Lifshitz gravity

We analyze the semiclassical Ho\v{r}ava-Lifshitz gravity for quantum scalar
fields in 3+1 dimensions. The renormalizability of the theory requires that the
action of the scalar field contains terms with six spatial derivatives of the
field, i.e. in the UV, the classical action of the scalar field should preserve
the anisotropic scaling symmetry ($t \to L^{2z}t,$ $\vec{x} \to L^2 \vec{x}$,
with $z=3$) of the gravitational action. We discuss the renormalization
procedure based on adiabatic subtraction and dimensional regularization in the
weak field approximation. We verify that the divergent terms in the adiabatic
expansion of the expectation value of the energy-momentum tensor of the scalar
field contain up to six spatial derivatives, but do not contain more than two
time derivatives. We compute explicitly the counterterms needed for the
renormalization of the theory up to second adiabatic order and evaluate the
associated $\beta$ functions in the minimal subtraction scheme.Comment: 8 page
Stability of Scalar Fields in Warped Extra Dimensions

This work sets up a general theoretical framework to study stability of
models with a warped extra dimension where N scalar fields couple minimally to
gravity. Our analysis encompasses Randall-Sundrum models with branes and bulk
scalars, and general domain-wall models. We derive the Schrodinger equation
governing the spin-0 spectrum of perturbations of such a system. This result is
specialized to potentials generated using fake supergravity, and we show that
models without branes are free of tachyonic modes. Turning to the existence of
zero modes, we prove a criterion which relates the number of normalizable zero
modes to the parities of the scalar fields. Constructions with definite parity
and only odd scalars are shown to be free of zero modes and are hence
perturbatively stable. We give two explicit examples of domain-wall models with
a soft wall, one which admits a zero mode and one which does not. The latter is
an example of a model that stabilizes a compact extra dimension using only bulk
scalars and does not require dynamical branes.Comment: 25 pages, 2 figures; v2: minor changes to text, references added,
  matches published versio
On hypercharge flux and exotics in F-theory GUTs

We study SU(5) Grand Unified Theories within a local framework in F-theory
with multiple extra U(1) symmetries arising from a small monodromy group. The
use of hypercharge flux for doublet-triplet splitting implies massless exotics
in the spectrum that are protected from obtaining a mass by the U(1)
symmetries. We find that lifting the exotics by giving vacuum expectation
values to some GUT singlets spontaneously breaks all the U(1) symmetries which
implies that proton decay operators are induced. If we impose an additional
R-parity symmetry by hand we find all the exotics can be lifted while proton
decay operators are still forbidden. These models can retain the gauge coupling
unification accuracy of the MSSM at 1-loop. For models where the generations
are distributed across multiple curves we also present a motivation for the
quark-lepton mass splittings at the GUT scale based on a Froggatt-Nielsen
approach to flavour.Comment: 38 pages; v2: emphasised possibility of avoiding exotics in models
  without a global E8 structure, added ref, journal versio
The Custodial Randall-Sundrum Model: From Precision Tests to Higgs
  Physics

We reexamine the Randall-Sundrum (RS) model with enlarged gauge symmetry
SU(2)_L x SU(2)_R x U(1)_X x P_LR in the presence of a brane-localized Higgs
sector. In contrast to the existing literature, we perform the Kaluza-Klein
(KK) decomposition within the mass basis, which avoids the truncation of the KK
towers. Expanding the low-energy spectrum as well as the gauge couplings in
powers of the Higgs vacuum expectation value, we obtain analytic formulas which
allow for a deep understanding of the model-specific protection mechanisms of
the T parameter and the left-handed Z-boson couplings. In particular, in the
latter case we explain which contributions escape protection and identify them
with the irreducible sources of P_LR symmetry breaking. We furthermore show
explicitly that no protection mechanism is present in the charged-current
sector confirming existing model-independent findings. The main focus of the
phenomenological part of our work is a detailed discussion of Higgs-boson
couplings and their impact on physics at the CERN Large Hadron Collider. For
the first time, a complete one-loop calculation of all relevant Higgs-boson
production and decay channels is presented, incorporating the effects stemming
from the extended electroweak gauge-boson and fermion sectors.Comment: 74 pages, 13 figures, 3 tables. v2: Matches version published in JHE
Flavor Physics in the Randall-Sundrum Model: II. Tree-Level
  Weak-Interaction Processes

A comprehensive analysis of tree-level weak interaction processes at low
energy is presented for the Randall-Sundrum (RS) model with SU(2)_L * U(1)_Y
bulk gauge symmetry and brane-localized Higgs sector. The complete form of the
effective weak Hamiltonian is obtained, which results from tree-level exchange
of Kaluza-Klein (KK) gluons and photons, the W^+- and Z^0 bosons and their KK
excitations, as well as the Higgs boson. Exact expressions are used for the
bulk profiles of the various fields, and for the exchange of entire towers of
KK gauge-boson states. A detailed phenomenological analysis is performed for
potential new-physics effects in neutral-meson mixing and in rare decays of
kaons and B mesons, including both inclusive and exclusive processes. We find
that while the predictions for \Delta(F)=2 observables are rather
model-independent, \Delta(F)=1 processes depend sensitively on the exact
realizations of the electroweak gauge and the fermionic sector. In this
context, we emphasize that the localization of the right-handed top quark in
the extra dimension plays a crucial role in the case of rare Z^0-mediated
decays, as it determines the relative size of left- to right-handed couplings.
We also extend earlier studies of quark flavor-changing neutral currents by
examining observables which up to now attracted little attention. These include
D-D(bar) mixing, B-->\tau\nu, B-->X_s (K^*) l^+ l^-, \epsilon_K'/\epsilon_K,
B-->\pi K, B^0-->\phi K_S, B^0-->\eta' K_S, and B^+-->\pi^+\pi^0.Comment: 112 pages (sorry!), 22 figures; v2: Extended version of the JHEP
  publicatio
Discovery potential of top-partners in a realistic composite Higgs model
  with early LHC data

Composite Higgs models provide a natural, non-supersymmetric solution to the
hierarchy problem. In these models, one or more sets of heavy top-partners are
typically introduced. Some of these new quarks can be relatively light, with a
mass of a few hundred GeV, and could be observed with the early LHC collision
data expected to be collected during 2010. We analyse in detail the collider
signatures that these new quarks can produce. We show that final states with
two (same-sign) or three leptons are the most promising discovery channels.
They can yield a 5 sigma excess over the Standard Model expectation already
with the 2010 LHC collision data. Exotic quarks of charge 5/3 are a distinctive
feature of this model. We present a new method to reconstruct their masses from
their leptonic decay without relying on jets in the final state.Comment: 28 pages 11 Figures 7 Tables, minor changes, added references,
  matches published versio
F-theory and the LHC: Stau Search

F-theory GUT models favor a relatively narrow range of soft supersymmetry
breaking parameters in the MSSM Lagrangian. This leads to the specific
predictions that a 10-100 MeV mass gravitino is the LSP, and the NLSP is
quasi-stable, with a lifetime between a second to an hour. In a wide range of
parameter space, the NLSP turns out to be a stau, though a bino-like lightest
neutralino is also possible. Focusing on F-theory GUTs with a stau NLSP, we
study the discovery potential at the LHC for such scenarios. Models with a
quasi-stable stau predict a striking signature of a heavy charged particle
passing through the detector. As a function of the parameters of minimal
F-theory GUTs, we study how many of such events to expect, and additional
signatures correlated with the presence of quasi-stable staus. We also study
the prospects for staus to become stopped in or near the detector, as well as
potential ways to distinguish such models from minimal gauge mediation models
with similar spectra.Comment: v2: 75 pages, 29 figures, references adde
The Minimal Scale Invariant Extension of the Standard Model

We perform a systematic analysis of an extension of the Standard Model that
includes a complex singlet scalar field and is scale invariant at the tree
level. We call such a model the Minimal Scale Invariant extension of the
Standard Model (MSISM). The tree-level scale invariance of the model is
explicitly broken by quantum corrections, which can trigger electroweak
symmetry breaking and potentially provide a mechanism for solving the gauge
hierarchy problem. Even though the scale invariant Standard Model is not a
realistic scenario, the addition of a complex singlet scalar field may result
in a perturbative and phenomenologically viable theory. We present a complete
classification of the flat directions which may occur in the classical scalar
potential of the MSISM. After calculating the one-loop effective potential of
the MSISM, we investigate a number of representative scenarios and determine
their scalar boson mass spectra, as well as their perturbatively allowed
parameter space compatible with electroweak precision data. We discuss the
phenomenological implications of these scenarios, in particular, whether they
realize explicit or spontaneous CP violation, neutrino masses or provide dark
matter candidates. In particular, we find a new minimal scale-invariant model
of maximal spontaneous CP violation which can stay perturbative up to
Planck-mass energy scales, without introducing an unnaturally large hierarchy
in the scalar-potential couplings.Comment: 71 pages, 34 eps figures, numerical error corrected, clarifying
  comments adde
Correlation Functions and Hidden Conformal Symmetry of Kerr Black Holes

Extremal scalar three-point correlators in the near-NHEK geometry of Kerr
black holes have recently been shown to agree with the result expected from a
holographically dual non-chiral two-dimensional conformal field theory. In this
paper we extend this calculation to extremal three-point functions of scalars
in a general Kerr black hole which need not obey the extremality condition
$M=\sqrt{J}$. It was recently argued that for low frequency scalars in the Kerr
geometry there is a dual conformal field theory description which determines
the interactions in this regime. Our results support this conjecture.
Furthermore, we formulate a recipe for calculating finite-temperature retarded
three-point correlation functions which is applicable to a large class of (even
non-extremal) correlators, and discuss the vanishing of the extremal couplings.Comment: 16 page
Seesaw Type I and III at the LHeC

We study the potential of testing the seesaw type I and III models at the
LHeC, an e-p collision mode at the CERN collider. The e-p collision mode
provides an excellent place to study lepton number violating process e^- p \to
N j + X \to l^+ W^- j + X with W^- into hadron jets. Here N is a heavy Majorana
neutrino and j is a hard hadron jet. With the electron energy E_e = 140 GeV and
proton energy E_p = 7 TeV, we find that the cross section for the heavy
neutrino N production can be as large as a few fb for the mass scale as high as
1 TeV, higher than what can be achieved by the p-p collision mode of LHC with
the same related heavy neutrino couplings.Comment: 20 pages, 6 figure