Conveners
Parallel Session B: CHOU CHIEN-YU, Kohta Hatakeyama, Naoki Fukushima, Yui Hayashi, Hiromasa Watanabe, Akira Matsumoto
- Kohtaroh Miura (KEK-IPNS)
Parallel Session B: Worapat Piensuk, Naoyuki Yamamori, Ashutosh Tripathi, Yuhma Asano, Ken Kikuchi, Keisuke Konosu
- Matsuo Sato (Hirosaki University)
Parallel Session B: Soichiro Shimamori, Hiroki Wada, Ryo Yokokura, Sinya Aoki, Matsuo Sato, Ryota Nasu
- Junichi Haruna (Osaka University)
Parallel Session B: Hidenori Fukaya, Atis Yosprakob, Gota Tanaka, Jingjing Yang, Mingshuo Zhu
- Kazutoshi Ohta (Meiji Gakuin University)
Quantum cosmology investigates the origins of our Universe, including the concept of "tunneling from nothing" proposed by Vilenkin and Hartle-Hawking. Recent advancements have renewed interest in this field, employing the Picard-Lefschetz theory in Lorentzian quantum gravity. In this study, we address crucial challenges using the generalized Lefschetz thimble method, overcoming the sign...
The Lorentzian type IIB matrix model is a promising candidate for a non-perturbative formulation of superstring theory. Recently, we have performed complex Langevin simulations adding a Lorentz invariant mass term as an IR regulator. In this talk, we will show that the (3+1)-dimensional expanding space-time emerges due to the effect of fermions.
The local gauge symmetry remaining even after imposing a gauge fixing condition is called the residual local gauge symmetry, which is spontaneously broken in the perturbative vacuum, and is expected to be restored in the true confining vacuum. Indeed, the criterion for restoring a special choice of the residual gauge symmetry was shown to be equivalent to the Kugo-Ojima color confinement...
Bifundamental QCD, an $SU(N) \times SU(N)$ gauge theory with a bifundamental fermion, has received substantial attention due to its rich phase structure and its notable relevance to the large-$N$ orbifold equivalence. To investigate the vacuum structure and phase diagrams of this model, we employ a semiclassical center-vortex description of the confining vacuum, enabled through...
Motivated by the picture of partial deconfinement developed in recent years for large-N gauge theories, we propose a new way of analyzing and understanding thermal phase transition in QCD. We find nontrivial support for our proposal by analyzing the lattice configuration for 4d SU(3) QCD with dynamical quarks, produced by WHOT-QCD collaboration. In the discussion, the Polyakov line plays a...
We propose three distinct methods to compute the mass of composite particles (hadrons) of gauge theories in the Hamiltonian formalism. Determination of the mass spectrum of hadrons is one of the key issues in QCD, which has been precisely calculated by the Monte Carlo simulation based on the Lagrangian formalism. We newly show how to compute the mass spectra in the Hamiltonian formalism, which...
The IKKT matrix model was proposed in 1996 as a non-perturbative description of superstring theory. One of its appealing features is the fact that spacetime emerges naturally from first principles as the eigenvalue distribution of the bosonic matrix degrees of freedom. For the past few decades, there has been extensive number of numerical attempts to study the model. In this work, we...
The IKKT matrix model is the most promising candidate of a non-perturbative formulation of superstring theory. Recently it has been proposed to introduce the Lorentz invariant mass term as a regularization. This model has SO(9,1) Lorentz symmetry, and a partition function diverges due to the non-compactness of the volume of the Lorentz group. In this study, we have done the analytical...
The type IIB matrix model is a promising candidate for a nonperturbative definition of superstring theory. The Lorentzian version, however, is not well defined as it is, and it was recently proposed to introduce a Lorentz invariant mass term in the action as an IR regulator. Depending on the sign of this term, we either have a model that is truly Lorentzian or one that is comparable to the...
In this talk, we revisit the "derivation" of the IKKT matrix model from perturbative string theory and discuss how we should define the path integral of the matrix model. In course of the "derivation," we will see that kappa symmetry is formally enhanced and that there is a subalgebra of the gauge symmetry closed off-shell, in sharp contrast to the fact that the kappa symmetry in the...
One of the goals in quantum field theory is to identify long distance behaviors of a theory defined at a short distance. One criterion to distinguish long distance behaviors is the precense of gap. When it is gapped, in two-dimensional space(time), the phases stand in bijection with module categories. In particular, ground state degeneracies (GSDs) of gapped phases are given by ranks of module...
Homotopy algebras algebras have been contributed to describe string field theory effectively. Recently, it has been recognized that these algebras can also be used to express quantum field theory, and its formulas are believed to be universal. In the recent research, it is presented that correlation functions of scalar field theories can be written in terms of homotopy algebras. In this talk,...
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...
We consider non-invertible symmetries in Maxwell theories on a non-spin manifolds. Since line operators can be either bosonic or fermionic on such manifolds, three slightly different Maxwell theories without an anomaly can be formulated. We investigate the behaviors of these theories under gauging one-form symmetries, and construct non-invertible symmetries on these theories from half gauging.
We demonstrate a universal mechanism of a class of instabilities in infrared regions for massless Abelian p-form gauge theories with topological interactions, which we call generalized chiral instabilities. Such instabilities occur in the presence of initial electric fields for the p-form gauge fields. We show that the dynamically generated magnetic fields tend to decrease the initial electric...
We summarize our recent attempt to construct a bulk spacetime from a scalar CFT such as an O(N) vector model by a conformal flow, which generates bulk fields from boundary scalar fields by smearing them. In this approach, bulk correlation functions are completely determined by the boundary theory, while bulk geometry is unspecified. We propose a method to determine the bulk geometry depending...
String geometry theory is one of the candidates of the non-perturbative formulation of string theory. In this theory, strings constitute not only particles but also the space-time. In this talk, in string geometry theory, we identify perturbative vacua in string theory, which include general string backgrounds. From fluctuations around these vacua, we derive the path-integrals of perturbative...
It has been suggested that quantum error correction plays a significant role in the AdS/CFT correspondence. It has also been pointed out that a tensor network given by MERA can be viewed as bulk space emerging from a boundary theory through the structure of the renormalization group. Motivated by these insights, we demonstrate that the renormalization group serves as an approximate quantum...
We propose a mathematical formulation of the Atiyah-Singer index on a lattice. Employing a one-parameter family of the massive Wilson Dirac operator, our lattice definition of the index does not rely on chiral symmetry or Ginsparg-Wilson relation. We give a mathematical proof that at fine but finite lattice spacing, our definition converges to the index in the continuum theory. This talk is...
Dealing with multiple flavors of Wilson fermions with Grassmann TRG is known to be difficult due to the exponential growth of the tensor size. Here, we propose a way to overcome this problem by separating the initial tensor into layers, each corresponding to different flavor. A compression scheme for the initial tensor is also proposed to further reduce the size. We test our method by studying...
The tensor renormalization group (TRG) method was originally proposed in condensed matter physics and has recently been drawing attention in particle physics. We investigated the shape dependence of entanglement entropy in the two-dimensional Ising model using the TRG method and obtained the central charge of the theory from the scaling property of entanglement entropy. We also developed a...
In this talk, I will discuss the application of the exact WKB analysis to a couple of one-dimensional Schrödinger-type equations reduced from the Stark effect of hydrogen. By introducing Langer’s modification, we prove the exactness of the Bohr-Sommerfeld quantization conditions for the Borel-resummed quantum WKB periods at the weak electric field intensities and also find these quantization...
