# High Energy Physics - Theory

## New submissions

[ total of 37 entries: 1-37 ]
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### New submissions for Mon, 25 Sep 17

[1]
Title: When Rational Sections Become Cyclic: Gauge Enhancement in F-theory via Mordell--Weil Torsion
Subjects: High Energy Physics - Theory (hep-th)

We explore novel gauge enhancements from abelian to non-simply-connected gauge groups in F-theory. To this end we consider complex structure deformations of elliptic fibrations with a Mordell--Weil group of rank one and identify the conditions under which the generating section becomes torsional. For the specific case of Z2 torsion we construct the generic solution to these conditions and show that the associated F-theory compactification exhibits the global gauge group [SU(2) x SU(4)]/Z2 x SU(2). The subsolution with gauge group SU(2)/Z2 x SU(2), for which we provide a global resolution, is related by a further complex structure deformation to a genus-one fibration with a bisection whose Jacobian has a Z2 torsional section. While an analysis of the spectrum on the Jacobian fibration reveals an SU(2)/Z2 x Z2 gauge theory, reproducing this result from the bisection geometry raises some conceptual puzzles about F-theory on genus-one fibrations.

[2]
Title: Higher spin matrix models
Subjects: High Energy Physics - Theory (hep-th)

We propose a hybrid class of theories for higher spin gravity and matrix models, i.e. which handle simultaneously higher spin gravity fields and matrix models. The construction is similar to Vasiliev's higher spin gravity but part of the equations of motion are provided by the action principle of a matrix model. In particular we construct a higher spin (gravity) matrix model related to type IIB matrix models/string theory which have a well defined classical limit, and which is compatible with higher spin gravity in $AdS$ space. As it has been suggested that higher spin gravity should be related to string theory in a high energy (tensionless) regime, and therefore to M-Theory, we expect that our construction will be useful to explore concrete connections.

[3]
Title: SYK Model, Chaos and Conserved Charge
Subjects: High Energy Physics - Theory (hep-th)

We study the SYK model with complex fermions, in the presence of an all-to-all $q$-body interaction, with a non-vanishing chemical potential. We find that, in the large $q$ limit, this model can be solved exactly and the corresponding Lyapunov exponent can be obtained semi-analytically. The resulting Lyapunov exponent is a sensitive function of the chemical potential $\mu$. Even when the coupling $J$, which corresponds to the disorder averaged values of the all to all fermion interaction, is large, values of $\mu$ which are exponentially small compared to $J$ lead to suppression of the Lyapunov exponent.

[4]
Title: Asymptotic symmetries and geometry on the boundary in the first order formalism
Authors: Yegor Korovin
Subjects: High Energy Physics - Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc)

Proper understanding of the geometry on the boundary of a spacetime is a critical step on the way to extending holography to spaces with non-AdS asymptotics. In general the boundary cannot be described in terms of the Riemannian geometry and the first order formalism is more appropriate as we show. We analyze the asymptotic symmetries in the first order formalism for large classes of theories on AdS, Lifshitz or flat space. In all cases the asymptotic symmetry algebra is realized on the first order variables as a gauged symmetry algebra. First order formalism geometrizes and simplifies the analysis. We apply our framework to the issue of scale versus conformal invariance in AdS/CFT and obtain new perspective on the structure of asymptotic expansions for AdS and flat spaces.

[5]
Title: Cohomogeneity-one-string integrability of spacetimes
Subjects: High Energy Physics - Theory (hep-th)

We present a framework for reducing all possible cohomogeneity-one strings, i.e., strings with geometrical symmetry, in a given spacetime to mechanical systems, and for analyzing integrability of the systems. As applications, it is clarified whether the systems of cohomogeneity-one strings in $AdS_5$, $AdS_5 \times S^5$, and $AdS_5 \times T^{p,q}$ are integrable or not. This method may reveal a different type of hidden symmetry of spacetimes.

[6]
Title: Multifractional spacetimes from the Standard Model to cosmology
Comments: 14 pages, 1 figure, 4 tables. In Proceedings of the XXV International Fall Workshop on Geometry and Physics (IFWGP), August 29 - September 02, 2016, Madrid, Spain
Subjects: High Energy Physics - Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc)

We review recent theoretical progress and observational constraints on multifractional spacetimes, geometries that change with the probed scale. On the theoretical side, the basic structure of the Standard Model and of the gravitational action is discussed. On the experimental side, we recall the bounds on the scales of the geometry coming from particle physics, astrophysics, and the cosmic microwave background.

[7]
Title: Massless Spectra and Gauge Couplings at One-Loop on Non-Factorisable Toroidal Orientifolds
Subjects: High Energy Physics - Theory (hep-th)

So-called `non-factorisable' toroidal orbifolds can be rewritten in a factorised form as a product of three two-tori by imposing an additional shift symmetry. This finding of Blaszczyk et al. [Blaszczyk:2011hs] provides a new avenue to Conformal Field Theory methods, by which the vector-like massless matter spectrum - and thereby the type of gauge group enhancement on orientifold invariant fractional D6-branes - and the one-loop corrections to the gauge couplings in Type IIA orientifold theories can be computed in addition to the well-established chiral matter spectrum derived from topological intersection numbers among three-cycles. We demonstrate this framework for the $\Z_4 \times \OR$ orientifolds on the $A_3 \times A_1 \times B_2$-type torus. As observed before for factorisable backgrounds, also here the one-loop correction can drive the gauge groups to stronger coupling as demonstrated by means of a four-generation Pati-Salam example.

[8]
Title: Embedding three-dimensional bosonization dualities into string theory
Subjects: High Energy Physics - Theory (hep-th)

We give simple string theory embeddings of several recently introduced dualities between 2+1-dimensional Chern-Simons matter theories using probe brane holography. Our construction is reliable in the limit of a large number of colors $N$ with fixed Chern-Simons level $k$.

### Cross-lists for Mon, 25 Sep 17

[9]  arXiv:1709.03696 (cross-list from gr-qc) [pdf, other]
Title: Status of the asymptotic safety paradigm for quantum gravity and matter
Authors: Astrid Eichhorn
Comments: 21 pages; extended version of a talk given at the workshop on Black Holes, Gravitational Waves and Spacetime Singularities, May 2017, Specola Vaticana; prepared for the proceedings of the workshop
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

In the asymptotic safety paradigm, a quantum field theory reaches a regime with quantum scale invariance in the ultraviolet, which is described by an interacting fixed point of the Renormalization Group. Compelling hints for the viability of asymptotic safety in quantum gravity exist, mainly obtained from applications of the functional Renormalization Group. The impact of asymptotically safe quantum fluctuations of gravity at and beyond the Planck scale could at the same time induce an ultraviolet completion for the Standard Model of particle physics with high predictive power.

[10]  arXiv:1709.07451 (cross-list from astro-ph.CO) [pdf, other]
Title: Vacuum dynamics in the Universe versus a rigid $Λ=$const
Comments: Published in Int. J. Mod. Phys. A32 (2017) 1730014. arXiv admin note: text overlap with arXiv:1705.06723
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

In this year, in which we celebrate 100 years of the cosmological term, $\Lambda$, in Einstein's gravitational field equations, we are still facing the crucial question whether $\Lambda$ is truly a fundamental constant or a mildly evolving dynamical variable. After many theoretical attempts to understand the meaning of $\Lambda$, and in view of the enhanced accuracy of the cosmological observations, it seems now mandatory that this issue should be first settled empirically before further theoretical speculations on its ultimate nature. In this work, we summarize the situation of some of these studies. Devoted analyses made recently show that the $\Lambda=$const. hypothesis, despite being the simplest, may well not be the most favored one. The overall fit to the cosmological observables $SNIa+BAO+H(z)+LSS+CMB$ singles out the class RVM of the "running" vacuum models, in which $\Lambda=\Lambda(H)$ is an affine power-law function of the Hubble rate. It turns out that the performance of the RVM as compared to the "concordance" $\Lambda$CDM model (with $\Lambda=$const.) is much better. The evidence in support of the RVM may reach $\sim 4\sigma$ c.l., and is bolstered with Akaike and Bayesian criteria providing strong evidence in favor of the RVM option. We also address the implications of this framework on the tension between the CMB and local measurements of the current Hubble parameter.

[11]  arXiv:1709.07456 (cross-list from gr-qc) [pdf, ps, other]
Title: On symmetry inheritance of the nonminimally coupled scalar fields
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)

We present the first symmetry inheritance analysis of the fields nonminimally coupled to gravity. In this work we are focused on the real scalar field $\phi$ with nonminimal coupling of the form $\xi\phi^2 R$. Possible cases of the symmetry noninheriting fields are constrained by the properties of the Ricci tensor and the scalar potential. Examples of such spacetimes can be found among those which are "dressed" with the stealth scalar field, a nontrivial scalar field configuration with the vanishing energy-momentum tensor. We classify the scalar field potentials which allow the symmetry noninheriting stealth field configurations on top of the exact solutions of the Einstein's gravitational field equation with the cosmological constant.

[12]  arXiv:1709.07464 (cross-list from astro-ph.CO) [pdf, ps, other]
Title: Primordial perturbations with pre-inflationary bounce
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)

Based on the effective field theory (EFT) of nonsingular cosmologies, we build a stable model, without the ghost and gradient instabilities, of bounce inflation (inflation is preceded by a cosmological bounce). We perform a full simulation for the evolution of scalar perturbation, and find that the perturbation spectrum has a large-scale suppression (as expected), which is consistent with the power deficit of the cosmic microwave background (CMB) TT-spectrum at low multipoles, but unexpectedly, it also shows itself one marked lower valley, which actually provides a better fit to the dip at multipole $l\sim 20$. The depth of valley is relevant with the physics around the bounce scale, which is model-dependent.

[13]  arXiv:1709.07477 (cross-list from hep-ph) [pdf, ps, other]
Title: On the observable spectrum of theories with a Brout-Englert-Higgs effect
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Lattice (hep-lat); High Energy Physics - Theory (hep-th)

The physical, observable spectrum in gauge theories is made up from gauge-invariant states. In the standard model the Fr\"ohlich-Morchio-Strocchi mechanism shows that these states can be adequately mapped to the gauge-dependent elementary $W$, $Z$ and Higgs states. In theories with a more general gauge group and Higgs sector this is no longer necessarily the case. We classify and predict the physical spectrum for a wide range of such theories, with special emphasis on GUT-like cases, and show that discrepancies between the spectrum of elementary fields and physical particles frequently arise.

[14]  arXiv:1709.07479 (cross-list from astro-ph.CO) [pdf, other]
Title: Primordial non-Gaussianity and power asymmetry with quantum gravitational effects in loop quantum cosmology
Comments: revtex4, one figure and no tables
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

Loop quantum cosmology (LQC) provides a resolution of the classical big bang singularity in the deep Planck era. The evolution, prior to the usual slow-roll inflation, naturally generates excited states at the onset of the slow-roll inflation. It is expected that these quantum gravitational effects could leave its fingerprints on the primordial perturbation spectrum and non-Gaussianity, and lead to some observational evidences in the cosmic microwave background (CMB). While the impact of the quantum effects on the primordial perturbation spectrum has been already studied and constrained by current data, in this paper we continue studying such effects on the non-Gaussianity of the primordial curvature perturbations. In this paper, we present detailed and analytical calculations of the non-Gaussianity and show explicitly that the corrections due to quantum effects are in the same magnitude of the slow-roll parameters in the observable scales and thus are well within current observational constraints. Despite this, we show that the non-Gaussianity in the squeezed limit can be enhanced at superhorizon scales and further, these effects may yield a large statistical anisotropy on the power spectrum through the Erickcek-Kamionkowski-Carroll mechanism.

[15]  arXiv:1709.07503 (cross-list from gr-qc) [pdf, other]
Title: Can the graviton have a large mass near black holes?
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

The mass of the graviton, if nonzero, is usually considered to be very small, e.g. of the Hubble scale, from several observational constraints. In this paper, we propose a gravity model where the graviton mass is very small in the usual weak gravity environments, below all the current graviton mass bounds, but becomes much larger in the strong gravity regime such as a black hole's vicinity. For black holes in this model, significant deviations from general relativity emerge very close to the black hole horizon and alter the black hole quasi-normal modes, which can be extracted from the ringdown waveform of black hole binary mergers. Also, the enhancement of the graviton mass near the horizon can result in echoes in the late time ringdown, which can be verified in the upcoming gravitational wave observations of higher sensitivity.

[16]  arXiv:1709.07718 (cross-list from hep-ph) [pdf, ps, other]
Title: The five-loop Beta function for a general gauge group and anomalous dimensions beyond Feynman gauge
Comments: 17 pages, 2 ancillary files files available with the source
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

We focus on a non-abelian gauge field coupled to a single (but general) representation of a family of Nf fermions. By using the same machinery that had allowed us to evaluate the sub-leading large-Nf term of the five-loop Beta function earlier, we here report on a confirmation of the all-Nf result that has in the meantime been published by another group. Furthermore, in order to push forward the 5-loop renormalization program regarding gauge parameter dependence, we present the linear terms of the complete set of anomalous dimensions, in an expansion in the covariant gauge parameter around the Feynman gauge.

[17]  arXiv:1709.07749 (cross-list from gr-qc) [pdf, ps, other]
Title: Does space-time torsion determine the minimum mass of gravitating particles?
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)

We derive upper and lower limits for the mass-radius ratio of spin-fluid spheres in Einstein-Cartan theory, with matter satisfying a linear barotropic equation of state, and in the presence of a cosmological constant. Adopting a spherically symmetric interior geometry, we obtain the generalized continuity and Tolman-Oppenheimer-Volkoff equations for a Weyssenhoff spin-fluid in hydrostatic equilibrium, expressed in terms of the effective mass, density and pressure, all of which contain additional contributions from the spin. The generalized Buchdahl inequality, which remains valid at any point in the interior, is obtained, and general theoretical limits for the maximum and minimum mass-radius ratios are derived. As an application of our results we obtain gravitational red shift bounds for compact spin-fluid objects, which may (in principle) be used for observational tests of Einstein-Cartan theory in an astrophysical context. We also briefly consider applications of the torsion-induced minimum mass to the spin-generalized strong gravity model for baryons/mesons, and show that the existence of quantum spin imposes a lower bound for spinning particles, which almost exactly reproduces the electron mass.

[18]  arXiv:1709.07765 (cross-list from hep-ph) [pdf, other]
Title: Two-Loop Renormalization Group Equations and Gauge Couplings Unification
Comments: 20 pages, 23 figures, 1 table
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

We analize the impact of two-loop renormalization group equations on the $SU(3)_c\times SU(2)_w\times U(1)_Y$ gauge couplings unification in various supersymmetric theories. In general the presence of superfields in higher representation than the doublet spoil the gauge couplings unification at one-loop. The situation is more interesting when the renormalization group equations are calculated at two-loop. In this case we show that the unification of the gauge couplings can be achieved for models with triplet superfield(s). In the analysis of the models with triplet superfield(s) we show that the dimensionless couplings do not have a Landau pole in their evolution at high energies but they run to a nontrivial ultraviolet fixed point.

[19]  arXiv:1709.07795 (cross-list from astro-ph.CO) [pdf, other]
Title: An effective description of dark energy: from theory to phenomenology
Comments: PhD thesis, defended on June 27th,2017 with original title "Tests de coh\'erence de l'Univers et reliques cosmiques"
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)

In the last decades, a cosmological model that fits observations through a vast range of scales emerged. It goes under the name of ${\Lambda}$CDM. However, there are still challenging questions that remain unanswered by this model, such as what causes the observed accelerated expansion of the universe, and many alternatives have been proposed. This thesis concerns an approach to test such models known as "Effective Theory of Dark Energy" . It applies to all models where general relativity is modified by adding a single scalar degree of freedom, called "scalar-tensor theories". In Chapter 1 I summarise the most general class of such theories currently known, called "Degenerate higher-Order Scalar-Tensor" (DHOST) theories. In Chapter 2, I introduce the effective theory of dark energy. The inclusion of a general coupling between matter and the gravitational sector is the subject of Chapter 3. Chapter 4 analyses in details the stability of different classes of theories. Notably, I show that the most general class of theories free from instabilities reduces to the so-called Horndeski and beyond-Horndeski theories, up to a non minimal coupling to matter. Another goal of the thesis is to study the observable effects of deviations from ${\Lambda}$CDM. In Chapter 5, I consider the possibility of an interaction between dark matter and dark energy and I analyse the constraining power of future surveys on the free parameters of the theory. Chapter 6 focuses on the observational effects of theories where a kinetic mixing between matter and the scalar field exists. This gives a peculiar and potentially observable effect, namely the weakening of gravity at large scale structure scales.

[20]  arXiv:1709.07845 (cross-list from gr-qc) [pdf, ps, other]
Title: Detecting quantum gravity in the sky
Comments: 5 pages, 1 figure. In Proceedings of EPS-HEP 2017, European Physical Society conference on High Energy Physics, July 5-12, 2017, Venice, Italy
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)

Getting signatures of quantum gravity is one of the topical lines of research in modern theoretical physics and cosmology. This short review faces this challenge under a novel perspective. Instead of separating quantum-gravity effects of a specific model between UV and IR regimes, we consider a general feature, possibly common to many frameworks, where all scales are affected and spacetime geometry is characterized by a complex critical exponent. This leaves a log-oscillating modulation pattern in the cosmic microwave background spectrum and gives a unique opportunity, illustrated with the example of a multi-fractional theory, to test quantum gravities at cosmological scales.

[21]  arXiv:1709.07853 (cross-list from astro-ph.CO) [pdf, other]
Title: Higgs inflation with loop corrections in the Palatini formulation
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)

We compare Higgs inflation in the metric and Palatini formulations of general relativity, with loop corrections are treated in a simple approximation. We consider Higgs inflation on the plateau, at a critical point, at a hilltop and in a false vacuum. In the last case there are only minor differences. Otherwise we find that in the Palatini formulation the tensor-to-scalar ratio is consistently suppressed, spanning the range $1\times10^{-13}<r<7\times10^{-5}$, compared to the metric case result $2\times10^{-5}<r<0.2$. Even when the values of $n_s$ and $r$ overlap, the running and running of the running are different in the two formulations. Therefore, if Higgs is the inflaton, inflationary observables can be used to distinguish between different gravitational degrees of freedom, in this case to determine whether the connection is an independent variable. Non-detection of $r$ in foreseeable future observations would not rule out Higgs inflation, only its metric variant. We conclude that in order to fix the theory of Higgs inflation, not only the particle physics UV completion but also the gravitational degrees of freedom have to be explicated.

### Replacements for Mon, 25 Sep 17

[22]  arXiv:1405.4821 (replaced) [pdf, ps, other]
Title: Large Hierarchy from Non-minimal Coupling
Authors: Chunshan Lin
Comments: 9 pages; v3: re-organize the paper, more discussions and references added;
Journal-ref: Commun. Theor. Phys. 68 (2017) 223-226
Subjects: High Energy Physics - Theory (hep-th); High Energy Physics - Phenomenology (hep-ph)
[23]  arXiv:1501.03159 (replaced) [pdf, other]
Title: TDiff and Weyl Invariant Massive Spin-2: Linear Theory
Comments: 37 pages, 2 figures. v3 some statements on equivalence corrected
Journal-ref: Phys. Rev. D 91, 125008 (2015)
Subjects: High Energy Physics - Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc)
[24]  arXiv:1502.04444 (replaced) [pdf, ps, other]
Title: Spherical T-Duality and the spherical Fourier-Mukai transform
Comments: 18 pages, major revision and results generalised
Subjects: High Energy Physics - Theory (hep-th); Differential Geometry (math.DG)
[25]  arXiv:1510.00023 (replaced) [pdf, ps, other]
Title: Normalizability analysis of the generalized quantum electrodynamics from the causal point of view
Comments: V2: 32 pages, affiliations updated, published version
Journal-ref: Int. J. Mod. Phys. A32, 1750165 (2017)
Subjects: High Energy Physics - Theory (hep-th); Mathematical Physics (math-ph)
[26]  arXiv:1607.06817 (replaced) [pdf, other]
Title: Holographic quenches and anomalous transport
Subjects: High Energy Physics - Theory (hep-th)
[27]  arXiv:1610.06087 (replaced) [pdf, ps, other]
Title: Hamiltonian Analysis of an On-shell U(1) Gauge Field Theory
Comments: 9 pages, no figure. V2: published version
Journal-ref: Phys. Lett. B ... (2017)
Subjects: Classical Physics (physics.class-ph); High Energy Physics - Theory (hep-th)
[28]  arXiv:1612.07116 (replaced) [pdf, ps, other]
Title: Cosmological singularity resolution from quantum gravity: the emergent-bouncing universe
Comments: 6 pages, 2 figures. Revised version accepted for publication in PRD. In this new version improved numerical simulations show damped oscillations in the pre- bounce phase. Full Discussion section added
Journal-ref: Phys. Rev. D 96, 046008 (2017)
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
[29]  arXiv:1701.07445 (replaced) [pdf, other]
Title: Emergent Supersymmetry in Local Equilibrium Systems
Authors: Ping Gao, Hong Liu
Subjects: High Energy Physics - Theory (hep-th); Statistical Mechanics (cond-mat.stat-mech); High Energy Physics - Phenomenology (hep-ph); Mathematical Physics (math-ph)
[30]  arXiv:1705.09010 (replaced) [pdf, other]
Title: Barnacles and Gravity
Journal-ref: JHEP 09 (2017) 080
Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
[31]  arXiv:1706.03773 (replaced) [pdf, other]
Title: Transport signatures of Hall viscosity
Subjects: Strongly Correlated Electrons (cond-mat.str-el); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); High Energy Physics - Theory (hep-th)
[32]  arXiv:1707.00716 (replaced) [pdf, other]
Title: Higher dimensional operators in 2HDM
Comments: 34 pages, 6 figures; to appear in JHEP
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
[33]  arXiv:1707.05820 (replaced) [pdf, other]
Title: Inflationary magneto-(non)genesis, increasing kinetic couplings, and the strong coupling problem
Comments: 19 pages plus references, 4 figures; v2, references and clarification added
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
[34]  arXiv:1707.09914 (replaced) [pdf, ps, other]
Title: On the ambiguity in the notion of transverse traceless modes of gravitational waves
Comments: 36 pages. The detailed of the Letter arXiv:1707.07729; some references and minor clarifications added
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
[35]  arXiv:1708.04631 (replaced) [pdf, other]
Title: AGT/Z$_2$
Comments: 56 pages. v2: Clarify discrete theta angle
Subjects: High Energy Physics - Theory (hep-th)
[36]  arXiv:1709.06964 (replaced) [pdf, ps, other]
Title: Rotating and spatially twisting Locally Rotationally Symmetric Spacetimes in f(R)-Gravity: a No-Go theorem
Title: Monodromy inflation at strong coupling: $4π$ in the sky