Shaoping Li, Osaka U
Resonant Forbidden Leptogenesis
Hybrid On-site: Kenkyu Honkan Seminar room 321, 322 Online: Zoom
Finite-temperature effects open more opportunities to explain the baryon asymmetry of the universe in minimal models beyond the standard model (SM). In this talk, I will introduce the forbidden CP asymmetry that is generated via soft-lepton resummation at finite temperatures and has a SM-predicted resonant enhancement. It features leptogenesis at the electroweak scale that is accessible at colliders, and dark matter cogenesis in the early universe.
Gary Shiu, UW Madison
The String Genome Project
Hybrid On-site: Kenkyu Honkan Seminar room 321, 322 Online: Zoom Considerations from both the Landscape and the Swampland suggest that 1) consistent quantum theories of gravity are rare in the space of all possible theories; 2) the number of consistent string vacua is enormous but finite. In light of these properties of quantum gravity, exhaustive searches for realistic vacua would not be feasible
Considerations from both the Landscape and the Swampland suggest that 1) consistent quantum theories of gravity are rare in the space of all possible theories; 2) the number of consistent string vacua is enormous but finite. In light of these properties of quantum gravity, exhaustive searches for realistic vacua would not be feasible
while random sampling would not be representative of the Landscape. In this talk, I will discuss how AI can be used to search for optimal solutions in string theory, to enumerate the exact number of solutions in regions of the Landscape and to discover structures therein, and to generate new Calabi-Yau compactifications.
Hidetoshi Omiya, Kyoto U
Impact of the self-interaction on the axion cloud and its gravitational wave signatures
Hybrid On-site: Kenkyu Honkan Seminar room 321, 322 Online: Zoom
The superradiant instability provides a promising avenue for detecting ultra-light axions through the formation of axion clouds around black holes. The way to observe the axion cloud includes observation of the spin of the black hole and the gravitational waves.To effectively observe these axions, it is crucial to have a precise understanding of the cloud’s evolution and its observable signatures. In this talk, I will discuss the impact of axion self-interaction on both the evolution of the cloud and its observational signatures. In particular, I will show that the self-interaction can produce signals in the different frequency bands.
Toru Kojo, KEK
[KEK-JAEA Joint Seminar] A quarkyonic matter model for dense QCD and hyperon problems
Hybrid On-site: Room 116, KEK Tokai campus Online: Zoom
Recent neutron star observations combined with the nuclear constraints suggest that QCD matter quickly stiffens at density close to nuclear matter density. We argue that the stiffening is triggered by a transition from nuclear to quark matter. The concept of quarkyonic matter captures relevant features necessary to understand the stiffening. We present an ideal model of quarkyonic matter and apply it to isospin symmetric and a matter of neutral baryons including the strangeness. We argue how the quark description mitigates the hyperon problems in neutron star constraints.
Justin Kaidi, Kyushu U
Non-Supersymmetric Heterotic Branes
Hybrid On-site: Kenkyu Honkan Seminar room 321, 322 Online: Zoom
The common statement that any consistent quantum gravity theory contains dynamical objects with all possible charges suggests that there are still a number of hitherto-unidentified branes in string theory. In this talk I will discuss four of these new branes, focusing on heterotic string theories. The focus of the discussion will be on the relationship between these branes and the lower-dimensional vacua obtained by closed string tachyon condensation in the ten-dimensional, non-supersymmetric heterotic string theories.
榎戸輝揚, 京都大学理学研究科/理化学研究所開拓研究本部
[金茶会] 宇宙放射線から切り拓く学際研究：高エネルギー大気物理学から月面物理学へ
4号館セミナーホール リモート会場：東海1号館115室、仁科記念棟106室 https://www-conf.kek.jp/kincha/
https://www-conf.kek.jp/kincha/
Ｘ線天文学を始めとする宇宙放射線の測定は、王道の高エネルギー天文学だけではなく、多様な学際研究を生み出している。たとえば、小型の放射線モニタを用いて、雷や雷雲からのガンマ線を測定することで、雷での光核反応の発見、雷雲での粒子加速機構の解明、雷のトリガーの謎などを扱う高エネルギー大気物理学が勃興している。これをシチズンサイエンスで推進すると同時に、放射線の多地点観測を月で展開し、月の水資源を探索する「MoMoTarO (Moon Moisture Targeting Observatory)」を開始した。月面に叩き込まれる銀河宇宙線は、月の表面で高速中性子を発生する。この中性子が表面から漏出する際に、水が存在すると効率よく運動エネルギーを失い、熱・熱外中性子として表面から漏出してくる。月面ローバーに搭載した中性子モニタで水資源を探すとともに、月周回機に搭載すれば中性子の寿命を測定でき、宇宙遠方からのガンマ線バーストを測定すれば、重力波宇宙論にも貢献することができる。宇宙放射線の視点で展開する多様な学際研究を紹介したい。
Andrew Jaffe, Imperial
The search for the topology of the Universe has only just begun
Hybrid On-site: Kenkyu Honkan Seminar room 321, 322 Online: Zoom
The topology of the Universe is not directly constrained by general relativity, and quantum mechanics may indeed prefer the creation of small Universes with nontrivial topologies. Large-scale cosmological measurements have shown no direct evidence of the patterns that would be induced in these cases, and the shortest distance around the Universe through us is unlikely to be much larger than the horizon diameter if microwave background anomalies are due to cosmic topology. I will discuss observational constraints from the lack of matched temperature circles in the microwave background which nonetheless leave many possibilities for such topologies, and further possibilities for their detection through large-scale correlations. I will also show that the large scale structure of space, rather than parity-violating microphysics, induces CMB parity violation in some topologies. Searches or topology signatures in observational data over the large space of possible topologies pose a formidable computational challenge, but is crucial for our understanding of the Universe.
Muping Chen, WPI-QUP, KEK
Halo-Independent Analysis of Light Dark Matter Direct Detection
Hybrid On-site: Kenkyu honkan, Seminar room Online: Zoom We demonstrate how the HI analysis can be applied to sub-GeV DM scattering off electrons for noble gas targets such as Xe and
We demonstrate how the HI analysis can be applied to sub-GeV DM scattering off electrons for noble gas targets such as Xe and
semiconductor targets such as Ge and Si. In the HI analysis method, properties of the local DM halo velocity distribution are inferred from direct DM detection data, which allows the comparison of different data sets without making any assumption on the uncertain local dark halo characteristics. This method had previously been developed for and applied only to DM scattering off nuclei. We additionally show that in-medium effects could significantly affect HI analysis results for semiconductor targets Ge and Si and thus are essential for proper inference of local DM halo characteristics from direct DM detection data.
Soichiro Shimamori, Osaka University
Non-invertible duality defect and fusion algebras in conformal field theories
Hybrid On-site: Kenkyu honkan, Seminar room Online: Zoom We study non-invertible duality symmetries by gauging a diagonal subgroup of a non-anomalous U(1) × U(1) global symmetry. In
We study non-invertible duality symmetries by gauging a diagonal subgroup of a non-anomalous U(1) × U(1) global symmetry. In
particular, we employ the half-space gauging to c=2 bosonic torus conformal field theory (CFT) in two dimensions and pure U(1) × U(1) gauge theory in four dimensions. In c=2 bosonic torus CFT, we show that the non-invertible symmetry obtained from the diagonal gauging becomes emergent on an irrational CFT point. We also calculate the fusion rules concerning the duality defect. We find out that the fusion algebra is non-commutative. We also obtain a similar result in pure U(1) × U(1) gauge theory in four dimensions. This presentation is based on the joint work with Yuta Nagoya [arXiv: 2309.05294, hep-th] .
西内満美子, QST関西量子科学研究所
[金茶会] レーザー駆動イオン加速研究−小型のイオン加速器実現に向けて
4号館セミナーホール リモート会場：JRB2階大会議室、仁科記念棟106室 https://www-conf.kek.jp/kincha/
