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.
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/
https://www-conf.kek.jp/kincha/
高強度レーザーと物質との相互作用により生成される相対論的プラズマは、高エネルギー粒子の発生源として認識されてから四半世紀が経とうとしている。発生するイオンビームの特徴が既存加速器からのイオンビームの特徴と異なるため、小型の加速器を含む、様々な応用先が提唱されてきており、それに向けたビームの良質化の研究が世界において精力的に行われている。本講演では、このレーザー駆動イオン加速研究に関し、歴史、背景、世界的な動向、最先端研究についてご紹介する。
Sean Hartnoll, Cambridge University
The polarised IKKT model
Online (Zoom)
The IKKT matrix model provides a holographic framework in which all spacetime dimensions are emergent. It remains poorly understood, not least because the ’timeless’ nature of the model means that the standard renormalisation group interpretation of the emergent ‘ radial’ dimension is not immediately applicable. I will discuss a supersymmetric deformation of the IKKT integral that gives a practical handle on the model. I will show how well-established phenomena, including brane polarisation in the presence of background fluxes, arise in this context and thereby allow the rudiments of a holographic dictionary to be established.
J. Richard Bond, Canadian Institute for Theoretical Astrophysics, University of Toronto
[KEK-Cosmo special colloquium] Entropy in a Coherent Universe: Quantum Information in the Action of the Cosmic SuperWeb
Seminar room, 3 go-kan
von Neumann of (thermal) quantum entropy fame purportedly responded to Shannon asking what his novel classical information content measure should be called: paraphrasing, entropy, nobody understands it anyway. Nowadays information entropy and thermal entropy have merged as ideas, and expanded to encompass phase info as well as counting info, aka quantum information. Its development and transport through all of the great cosmic epochs of instability accompanying transitions of phase is a unifying story of the Universe. This is a big topic which I will meander through, from the speculative emergence of coherence, through an inflation era, its preheating end in the matter-entropy burst, with attention on the cosmic neutrino background decoupling, cosmic photon thermal decoupling and its Compton scattering decoupling, and entropy development and transport in the gravitationally-unstable nonlinear cosmic web. With applications to observable entropic relics and the cosmic parameters we derive from them, such as the CnuB, CMB, the cosmic infrared background, line intensity mapping, and the thermal state of clusters, groups and the IGM. Whew, and that’s not all: one quest is for information-laden Planck-epoch non- Gaussianities, scalar and tensor, beyond Planck the satellite, and towards LiteBird.
Tomoya Kinugawa, Shinshu University
Gravitational waves from first star remnants
Hybrid On-site: Seminar room, Kenkyu honkan 3F Online: Zoom
We calculated binary evolutions of first stars (Pop III) and showed that the typical chirp mass of Pop III binary black holes is ∼30Msun with a total mass of ∼60Msun and the maximum mass of Pop III BBH is more massive than the limit mass of the pair instability supernovae. Our result, which predicted gravitational wave events like GW150914 and GW190521, can explain the origin of massive stellar binary black hole mergers. In this talk, I will explain Pop III binary evolutions and the properties of Pop III binary black hole mergers. There is a good chance to check indirectly the existence of Pop III massive stars by gravitational waves.
Yu Hamada, DESY
Gravitational wave from current-carrying domain walls
Hybrid On-site: Seminar room, Kenkyu honkan 3F Online: Zoom
Domain walls (DWs) are very common objects that appear in many BSM models with spontaneous breaking of discrete symmetries and have been widely studied in the context of gravitational wave observation. Depending on models, DWs can contain internal degrees of freedom such as fermionic zeromodes (like DW fermion in lattice QCD) or bosonic zeromodes. Such an object is called current-carrying DW as it can carry (dark) electric charge/current. In this talk, we will show gravitational wave spectrum radiated from current-carrying DWs can be quite different from conventional DWs. Particularly they can enhance UV regime of spectrum, increasing the detectability by future gravitational wave instruments.
宮原正也, KEK素核研・QUP
[金茶会] 半導体の技術トレンドと物理実験用ASIC開発
つくば：4号館セミナーホール リモート会場：AQBRC２階会議室、仁科記念棟106室 https://www-conf.kek.jp/kincha/
https://www-conf.kek.jp/kincha/
集積回路を中心とした半導体デバイスは現代の電子機器や情報化社会の根幹を支えており、物理実験においてもセンサの微細化、多チャンネル化に伴い高機能・高集積を実現する集積回路技術の重要度は日々増しています。
集積回路技術は今日まで約60年にわたりムーアの法則とも呼ばれるトランジスタの微細化と共に発展して来ました。しかしながら単純な微細化は物理的制約により終わりを迎え、今後の開発競争の見通しは困難なものとなっています。
日本国内では改めて半導体が国家の今後を左右する戦略物資として見直され、先端集積回路製造工場の誘致及び建設、並びにそれを支える人材育成の教育体制の構築と様々な動きが生じています。
本講演ではCMOS集積回路技術を中心とした半導体技術トレンドを俯瞰し、今後の物理実験に用いられるASICの開発のあり方について主観多めに論じます。
Chong-Sun Chu, National Tsing Hua University
A proposal for quantum gravity and quantum mechanics of black hole
Online (Zoom)
We propose a quantum mechanical theory of quantum spaces described by large $N$ noncommutative geometry as a model for quantum gravity. The theory admits fuzzy sphere and fuzzy ellipsoid as solution. We show that these solutions reproduces precisely the horizon radius of a Schwarzschild black hole and a Kerr black hole. Moreover our quantum mechanical description gives rise to a set of microstates over these geometries, which reproduces precisely the Bekenstein-Hawking entropy of black hole. These results provide strong support that our proposed theory of quantum spaces is a plausible candidate for the theory of quantum gravity.
References:
[1] 2406.01466 [hep-th]
A Matrix Model Proposal for Quantum Gravity and the Quantum Mechanics of Black Holes
[2] 2406.12704 [hep-th]
Quantum Kerr Black Hole from Matrix Theory of Quantum Gravity
[3] Recent unpublished results.
Giacomo Landini, Valencia U
Dark Matter from strongly coupled theories dark baryons and dark pions
Hybrid On-site: Seminar room 321, 322 Online: Zoom Understanding the nature of Dark Matter is one of the most significant open problems in particle physics and cosmology. In this talk, I will explore how Dark Matter candidates can naturally arise as composite bound states in new strongly coupled gauge sectors. I will focus on two specific realizations.
