Dynamo seeds from Gravitational Torsional Anomalies and De Sitter Magnetized Metrics

Recently gravitational and Nieh-Yan chiral anomalies have been obtained in Riemann-Cartan spacetime Class and Quantum Gravity 38 (2021)], where electrodynamics is encoddded in the metric. In this paper we follow the path of obtaining a class of deformed de Sitter metrics in teleparallelism. The existence of the unmagnetized DSMM without axial anomalies is proved. Here we obtain unified theories a la Einstein and Eddington and Schroedinger, called modified de Sitter metric (MDSM) with the novel following features: (i) First we show that a pure de Sitter unmagnetized metric in T4 does not induce gravitational anomalies. Therefore this is a motivation to study modifications of De Sitter metric. What is done in the following items. (ii) Nieh-Yan torsion anomaly in (DSMM) in teleparallel T4 geometry is shown to vanish in all cases. Gravitational non-tivial anomalies are obtained from these metrics. But torsional anomaly much used in condensed matter physics, does not vanish. From these magnetized metrics, we show that with dynamo equation with torsion gradients sources is valid from class 3 of the metrics but is torsionless sourced in second class. (iii) We show that in the gravitational anomaly of new deformed de Sitter metric one may cancell the gravitational anomaly by a proper choice of the metric function. The axial anomaly is obtained for some metric deformation as well. Use original de Sitter nonconformal metric . A simple deformation leads to the existence of the NY form in the case of magnetized de Sitter metric. This would be class IV of DSMM.

Chiral transport in curved spacetime via holography

We consider a holographic model of strongly interacting plasma with a gravitational anomaly. In this model, we compute parity-odd responses of the system at finite temperature and chemical potential to external electromagnetic and gravitational fields. Working within the linearized fluid/gravity duality, we performed the calculation up to the third order in gradient expansion. Besides reproducing the chiral magnetic (CME) and vortical (CVE) effects we also obtain gradient corrections to the CME and CVE due to the gravitational anomaly. Additionally, we find energy-momentum and current responses to the gravitational field similarly determined by the gravitational anomaly. The energy-momentum response is the first purely gravitational transport effect that has been related to quantum anomalies in a holographic theory.

Expanding on the Cardy-like limit of the SCI of 4d $$ \mathcal{N} $$ = 1 ABCD SCFTs

We study the Cardy-like limit of the superconformal index of generic $$ \mathcal{N} $$ N = 1 SCFTs with ABCD gauge algebra, providing strong evidence for a universal formula that captures the behavior of the index at finite order in the rank and in the fugacities associated to angular momenta. The formula extends previous results valid at lowest order, and generalizes them to generic SCFTs. We corroborate the validity of our proposal by studying several examples, beyond the well-understood toric class. We compute the index also for models without a weakly-coupled gravity dual, whose gravitational anomaly is not of order one.

Elliptic Calabi-Yau fivefolds and 2d (0,2) F-theory landscape

In this paper, we initiate the study of the 2d F-theory landscape based on compact elliptic Calabi-Yau fivefolds. In particular, we determine the boundary models of the landscape using Calabi-Yau fivefolds with the largest known Hodge numbers h1,1 and h4,1. The former gives rise to the largest geometric gauge group in the currently known 2d (0,2) supergravity landscape, which is $$ {E}_8^{482\;632\;421}\times {F}_4^{3\;224\;195\;728}\times {G}_2^{11\;927\;989\;964}\times \mathrm{SU}{(2)}^{25\;625\;222\;180} $$ E 8 482 632 421 × F 4 3 224 195 728 × G 2 11 927 989 964 × SU 2 25 625 222 180 . Besides that, we systematically study the hypersurfaces in weighted projective spaces with small degrees, and check the gravitational anomaly cancellation. Moreover, we also initiate the study of singular bases in 2d F-theory. We find that orbifold singularities on the base fourfold have non-zero contributions to the gravitational anomaly.

Refinement of parameters gravitational anomaly relative to the focal zone of the 2011 earthquake (Japan) based on satellite data

The aim of this work is to study gravitational anomalies that have arisen in the region of the sources of strong underwater earthquakes with a magnitude of Mw > 8. For this purpose, data obtained by the GRACE space system were used. Variations of the EWH program with a period of 30 days were investigated relative to the focal area of the 2011 Japanese earthquake for the period 2010-2012. It was found that during the preparation of an earthquake, the EWH values significantly increase in this area for three months, with aftershock activity, the EWH values decrease within a month. Maps of variations of the EWH parameter in the conditions of a disturbed geomedia and in background seismic conditions are constructed. The indices of the anomaly δEWH were calculated, which made it possible to analyze in more detail the local gravitational field for the investigated focal zone.

The UV fate of anomalous U(1)s and the Swampland

Massive U(1) gauge theories featuring parametrically light vectors are suspected to belong in the Swampland of consistent EFTs that cannot be embedded into a theory of quantum gravity. We study four-dimensional, chiral U(1) gauge theories that appear anomalous over a range of energies up to the scale of anomaly-cancelling massive chiral fermions. We show that such theories must be UV-completed at a finite cutoff below which a radial mode must appear, and cannot be decoupled — a Stückelberg limit does not exist. When the infrared fermion spectrum contains a mixed U(1)-gravitational anomaly, this class of theories provides a toy model of a boundary into the Swampland, for sufficiently small values of the vector mass. In this context, we show that the limit of a parametrically light vector comes at the cost of a quantum gravity scale that lies parametrically below MP1, and our result provides field theoretic evidence for the existence of a Swampland of EFTs that is disconnected from the subset of theories compatible with a gravitational UV-completion. Moreover, when the low energy theory also contains a U(1)3 anomaly, the Weak Gravity Conjecture scale makes an appearance in the form of a quantum gravity cutoff for values of the gauge coupling above a certain critical size.

A remark about the anomalies of cyclic holomorphic permutation orbifolds

Using a result of Longo and Xu, we show that the anomaly arising from a cyclic permutation orbifold of order 3 of a holomorphic conformal net [Formula: see text] with central charge [Formula: see text] depends on the “gravitational anomaly” [Formula: see text]. In particular, the conjecture that holomorphic permutation orbifolds are non-anomalous and therefore a stronger conjecture of Müger about braided crossed [Formula: see text]-categories arising from permutation orbifolds of completely rational conformal nets are wrong. More generally, we show that cyclic permutations of order [Formula: see text] are non-anomalous if and only if [Formula: see text] or [Formula: see text]. We also show that all cyclic permutation gaugings of [Formula: see text] arise from conformal nets.