Keiju Murata, Nihon University

Einstein Rings in Holography

##### Clarifying conditions for the existence of a gravitational picture for a given quantum field theory (QFT) is one of the fundamental problems in the AdS/CFT correspondence. We propose a direct way to demonstrate the existence of the dual black holes: imaging an Einstein ring. We consider a response function of the thermal QFT on a two-dimensional sphere under a time-periodic localized source. The dual gravity picture, if it exists, is a black hole in an asymptotic global AdS4 and a bulk probe field with a localized source on the AdS boundary. The response function corresponds to the asymptotic data of the bulk field propagating in the black hole spacetime. We find a formula that converts the response function to the image of the dual black hole: The view of the sky of the AdS bulk from a point on the boundary. Using the formula, we demonstrate that, for a thermal state dual to the Schwarzschild-AdS4 spacetime, the Einstein ring is constructed from the response function. The evaluated Einstein radius is found to be determined by the total energy of the dual QFT. Our theoretical proposal opens a door to gravitational phenomena on strongly correlated materials.

Miguel A. Vazquez-Mozo, Universidad de Salamanca

Anomalous fluids from differential geometry

##### In this talk I will discuss how differential geometry methods can be applied to the computation of the equilibrium partition function of anomalous fluids, as well as their associated currents. In the case of systems with spontaneous symmetry breaking, a direct calculation of the covariant currents is possible without relying on a previous evaluation of the, usually cumbersome, WZW effective action of Goldstone bosons. As an example, I will present the computation of the anomalous transport coefficients of a two-flavor chiral hadronic superfluid.

Hiroyuki Ishida, KEK

Baryogenesis in the nuMSM

##### The nuMSM is an extended standard model only with three right-handed neutrinos. The characteristic feature of the model is the masses of additional right-handed neutrino is constrained up to the electroweak scale. By this restriction, we cannot simply apply the leptogenesis scenario to produce the lepton asymmetry for the baryogenesis though sphaleron effect. However, the enough amount of the lepton asymmetry can be produced via another mechanism triggered by right-handed neutrino flavor oscillation. In this talk, I will explain the detail of the mechanism and dependence on the initial condition.

Tomohiro Fujita, Kyoto University

[Cosmophysics seminar] Ways to Hunt Axion Dark Matter: Observation and Experiment

##### Identification of dark matter has been an outstanding problem in physics for decades, and axion (or axion like partciles) is its candidate with great motivations. A number of observations and experiments have tried to detect axion by using the axion-photon conversion by assuming the axion is coupled to photon, while no signal yet to be found. In this talk, I will discuss new techniques to search for axion dark matter by focusing on another phenomena, birefringence, which is caused by the same coupling. The polarimetry observation of protoplanetary disks puts the best constraint on ADM for fuzzy dark matter mass (m = 10^{-22}eV). I also propose a table-top laser-cavity experiment as well as using gravitational wave interferometers to search in the intermediate mass range (10^{-17}eV < m < 10^{-10}eV).

Aldo Deandrea, Lyon 1 University

Fundamental strong dynamics beyond the Standard Model in the electroweak sector

Modern Composite Goldstone-Higgs models bases on a fundamental fermionic theory are promising candidates to dynamically and naturally generate the electroweak symmetry breaking. Apart from the Higgs boson other particles are present in the low energy spectrum. I will discuss the phenomenological implications of this class of models.

Sekiguchi Toyokazu, KEK

Smallest haloes in wino dark matter

##### Neutral wino is a natural candidate of dark matter in split-supersymmetry. Indirect detection is a promising probe of wino dark matter, with its annihilation enhanced non-perturvatively (i.e. Sommerfeld enhancement). In theoretical prediction, halo formation at the low-mass end is a key ingredient. For this purpose, we investigate kinetic decoupling of wino dark matter and consequent dark matter density perturbations. We show that inelastic processes involving charged wino, which are relevant for kinetic equilibrium at late times, shuts off abruptly. This results in boosted acoustic peaks in density power spectrum at horizon scales around the kinetic decoupling. Based on an analytic modeling of subhalo evolution, we estimate the subhalo mass function of (dwarf) galaxy-sized haloes and effects on the annihilation boost factor. We also discuss an application of our analysis to SU(2)_L multiplet minimal dark matter.

Yevgeny Stadnik, Kavli IPMU, University of Tokyo

Novel low-energy probes of dark matter

##### I present a brief overview of some novel detection strategies for ultra-low-mass bosonic dark matter that forms a coherently oscillating classical field. Possible effects of such dark-matter fields include apparent time-varying fundamental constants and time-varying spin-precession effects. These effects can be sought with a diverse variety of high-precision, low-energy (and often table-top) experiments, including: spectroscopy (clock) and optical cavity measurements, laser interferometers, atom interferometers, torsion pendula (fifth-force experiments), magnetic resonance techniques, and astrophysical measurements (such as big bang nucleosynthesis). Existing and new experimental and observational data have allowed us and other groups to improve on previous observational bounds on possible non-gravitational interactions of ultra-low-mass dark matter with ordinary matter by many orders of magnitude.

Kenji Kadota, Center for Theoretical Physics of the Universe (CTPU), Institute for Basic Science (IBS)

Radio telescope probes on the light dark matter

##### An overview for the light dark matter will be presented along with the illustration for the complementarity between the cosmology and particle physics probes. The concrete examples include the radio emission from the axion-photon conversion around the neutron star and the cross-correlations between the 21cm and the CMB B mode from the cosmological birefringence.

Christian Rohrhofer, Osaka University

Two Flavor QCD Spectrum and Symmetries at High Temperature

##### QCD matter and properties change significantly around the chiral crossover temperature, and so far the effects on chiral observables and thermodynamical quantities have been studied with much care.

Here I present the screening spectrum for light hadrons, which includes chiral partners of mesons as well as different nucleon operators and their parity partners.

Measurements are done with two flavors of chirally symmetric domain-wall fermions at temperatures above the critical one, for different volumes and quark-masses.

Emergent SU(4) and SU(2)_CS symmetries will be discussed, as well as their implications.

Luigi Accardi, University of Rome Tor Vergata

Extensions of Quantum Mechanics Canonically Emerging from the Theory of Orthogonal Polynomials