Gradient Flow and Its Applications Kengo Kikuchi Riken iTHEMS QFT-core seminar � Riken 2020/05/15
Introduce myself Kengo Kikuchi ������ : PhD in Osaka Univ. (Onogi-san and Higashijima-san) Reseach Theoretical physics, elementary particle physics, quantum field theory (Especially renormalization, non-perturbative methods, exact renormalization group, and gradient flow)
Concept of iTHEMS QFT-core The core group of research under the theme of the Quantum Field Theory including elementary particle theory, nuclear theory and Condensed Matter physics. They consists of two parts. iTHEMS QFT-core group 1. Basic and Pedagogical part 2. Advanced and Frontier part � Explore a systematic educational method � Research under the theme of the for undergraduate or graduate students, quantum field theory lecture series, intensive course � Seminar and journal club for theoretical � Introduction to other various field physicist This seminar researcher � Conference � In the tradition and sprit of Yoshio Nishina, the founder of Riken � “Quantum Field Theory is the ultimate dynamics human beings have ever achieved.”
� . Introduction
Let’s start from the very “elementary” story. What we made of? It is quark. “Sounds of Quarks” Can you hear the sounds of the quarks? Low energy High energy Everything is constructed by the huge number of quarks and each quarks ∞ have the information. There is a procedure to obtain the finite information form infinite In high energy scale, one information may be overflow. But we can listen the sound just only as Our brain cannot process information “PRESSURE”. too complicate and excess!! The procedure to take a meaningful finite quantity from infinite information � Renormalization
∞ “What makes the desert beautiful is that somewhere it hides a well.” � Le Petit Prince � Antoine de Saint-Exupéry
However, to eliminate divergence is not so easy… we need to renormalize the theories appropriately. To keep symmetry in the theories Sometimes, Renormalization and Symmetry are basically incompatible like oil and water, . Symmetry Renormalization � We talk about the new methods to eliminates the divergence to keep the symmetry, Gradient Flow
II. What is Gradient Flow?
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