Conveners
Parallel Session A: Kakeru Sugiura, Ryota Watanabe, Junichi Haruna, Pratik Nandy, Tomoki Nosaka, Yuuta Saito
- Takeshi Morita (Shizuoka University)
Parallel Session A: Yuji Ando, Mohammad Akhond, Shuichi Murayama, Takafumi Kai, Yuki Yokokura, Takeshi Morita
- Hajime Otsuka (Kyusyu University)
Parallel Session A: Motokazu Abe, Okuto Morikawa, Soma Onoda, Naoto Kan, Kazutoshi Ohta, Maki Takeuchi
- Hidenori Fukaya (Osaka University)
Parallel Session A: Gregory Loges, Yoshinori Matsuo, Cheng-Tsung Wang, Nikolo Zenoni, Hajime Otsuka, Keiichi Nagao
- Yuki Yokokura (RIKEN iTHEMS)
Photon spheres are the characteristic of general black holes, thus are a suitable touchstone for the emergence of gravitational spacetime in the AdS/CFT correspondence. We provide a spectral analysis of an AdS Schwarzschild black hole near its photon sphere. We find that quasinormal modes near the photon sphere reflect the AdS boundary, resulting in a peculiar spectral pattern. Our large...
Recently, Krylov complexity was proposed as a measure of complexity and chaoticity of quantum systems. We consider the stadium billiard as a typical example of the quantum mechanical system obtained by quantizing a classically chaotic system, and numerically evaluate Krylov complexity for operators and states. Despite no exponential growth of the Krylov complexity, we find a clear correlation...
We apply the gradient flow exact renormalisation group (GFERG) for scalar quantum electrodynamics. The flow equations for the Wilsonian effective action is derived by means of perturbative expansion in the gauge coupling. In this work, we deal with quantum corrections to the correlation functions up to second order of the gauge coupling. We demonstrate especially that the GFERG formalism...
Under the Hamiltonian evolution, a simple operator turns into a complicated operator. The growth of such an operator is drastically different when the system is connected to a dissipative environment than in a typical closed system. We probe such growth via a recently explored measure of scrambling known as Krylov complexity and aim to propose an operator growth hypothesis in open quantum...
We find new bilinear relations for the partition functions of $U (N)_k × U(N+M)_{−k}$ ABJ theory with two parameter mass deformation (m1,m2), which generalize the q-Toda-like equation found previously for m1=m2. By combining the bilinear relations with the Seiberg-like dualities and the duality cascade relations, we can determine the closed form expressions of the partition functions...
We talk about Page curves for 2d black holes with multiple injections. The feature is that a decreasing entanglement entropy related to time is replaced with a increasing one when a energy is injected. After each energy injection, we find a sudden increase in the entropy, and also subsequent increasing period. Then, after a "Page time", there comes a decreasing period untill the next energy...
In perturbative string theory, there have mainly been two ways to quantize the string. Either one quantizes in lightcone gauge, or one quantizes covariantly. The difference between them is only gauge condition, and the equivalence of on-shell amplitudes had been already shown. String field theory is a candidate for a non-perturbative formulation of string theory. There have mainly been two...
The giant graviton expansion of the superconformal index gives the finite rank corrections to the calculation of the index of the superconformal field theory via AdS/CFT correspondence. We study the giant graviton expansions focusing on the 4-dimensional N=2 superconformal field theories realized on D3-branes in 7-brane backgrounds with constant axiodilaton. For some theories including them,...
We examine symmetries of chiral four-dimensional vacua of Type IIB flux compactifications with vanishing superpotential W=0. We find that the N=1 supersymmetric MSSM-like and Pati-Salam vacua possess enhanced discrete symmetries in the effective action below the mass scale of stabilized complex structure moduli and dilaton. Furthermore, a generation number of quarks/leptons is small on these...
We consider a 4D spherically-symmetric static spacetime region as a collection of quanta in the semi-classical Einstein equation and study the entropy including the self-gravity. For sufficiently excited states, we estimate the entropy in a WKB-like method considering the non-locality of entropy and local consistency with thermodynamics and find its upper bound. The saturation condition...
In this talk, I demonstrate that scale invariance and electromagnetic duality are strong enough to restrict the spacetime dimension. 10 and 11 dimensional spacetimes are obtained as solutions of these constraints. In this derivation, supersymmetry and general relativity are not assumed.
We extend the definition of Lüscher's lattice topological charge to the case of 4d SU(N) gauge fields coupled with Z_N 2-form gauge fields. This result is achieved while maintaining the locality, the SU(N) gauge invariance, and Z_N 1-form gauge invariance, and we find that the manifest 1-form gauge invariance plays the central role in our construction. This result gives the lattice regularized...
We present the lattice simulation of the renormalization group flow in the 3-dimensional O(N) linear sigma model. This model possesses a nontrivial infrared fixed point, called Wilson-Fisher fixed point. Arguing that the parameter space of running coupling constants can be spanned by expectation values of operators evolved by the gradient flow, we exemplify a scaling behavior analysis based on...
The admissibility conditions are essential for obtaining a well-defined topological charge in lattice gauge theory. However, these conditions may naively seem to prohibit the existence of magnetic operators, as they automatically enforce the Bianchi identity. In this presentation, we will explain how this issue is addressed in the context of 2-dimensional compact scalar theories on a lattice....
The Witten effect predicts that a magnetic monopole acquires a fractional electric charge inside topological insulators. In this work, we give a microscopic description of this phenomenon as well as an analogous two-dimensional system with a vortex. We solve the Dirac equation of electron field both analytically in a continuum and numerically on a lattice by adding the Wilson term and smearing...
We discuss the phase structure of the fundamental Kazakov-Migdal (FKM) model, which is defined on graphs and a generalization of the Kazakov-Migdal model by replacing the scalar fields in the adjoint representation with the fundamental representation. We first show that the partition function of the FKM model can be represented by the unitary matrix valued graph zeta functions, which...
In this talk, we discuss the black hole/string transition in the black hole evaporation. Susskind proposed that a black hole turns into a highly excited string as one adiabatically decreases the string coupling. Horowitz and Polchinski constructed a model of string bound state which describes the string phase of the black hole/string transition. In the previous work, we extended the...
We revisit the connection between Hawking radiation and high-frequency dispersions for a Schwarzschild black hole following the work of Brout et al.. After confirming the robustness of Hawking radiation for monotonic dispersion relations, we consider non-monotonic dispersion relations that deviate from the standard relation only in the trans-Planckian domain. Contrary to the common belief that...
Holographic complexity is conjectured to probe the evolution of spacetime. For black holes in anti-de Sitter (AdS) spacetime the growth rate of complexity approaches a constant value at late times, while in de Sitter (dS) spacetime it diverges at a finite critical time. In this talk, we consider geometries interpolating between AdS and dS. In particular, we discuss the evolution of volume...
Sequestering is a promising mechanism in 4D string models to reconcile high scale inflation with low-energy supersymmetry. In this scenario the MSSM lives on branes at singularities and it is sequestered from the sources of supersymmetry breaking in the bulk. The soft-terms are suppressed with respect to the gravitino mass so that all moduli are heavy enough to avoid any cosmological moduli...
We previously proposed a mechanism to effectively obtain, after a long time development, a Hamiltonian being Hermitian with regard to a modified inner product $I_Q$ that makes a given non-normal Hamiltonian normal by using an appropriately chosen Hermitian operator $Q$. We studied it for pure states. In this talk we show that a similar mechanism also works for mixed states by introducing...
