Date: January 9-10 2020

Venue: Conference Room 6620 (1.10 afternoon session in 6420), Institute of Theoretical Physics, Chinese Academy of Sciences


We will have an informal workshop at ITP-CAS for Jan 9-10 on Quantum Field Theory and String Theory. The main topics include scattering amplitudes, CFT (bootstrap and related topics), and new mathematical structures therein.

We plan to have a loose schedule with plenty of time for free discussions. Any student who wish to give a short talk, please send an email to All are welcome to attend!


1st day 2nd day
10:00 Congkao Wen Ellis Yuan
13:00 Fei Teng Yu-tin Huang
14:30 Peng Zhao Ning Su
16:00 student talks (1-3) student talks (4-6)
Student talks:

1. Qinglin Yang 2. Zhenjie Li 3. Prashanth Raman 4. Chi Zhang 5. Wei Li 6. Yihui Zheng


Yu-tin Huang (NTU): Optimal Functionals of CFT and EFT

Ning Su (EPHL): Bootstrapping 3D N=1 SCFT

Abstract: Conformal bootstrap gives very precise determination of 3D Ising critical exponents. Despite the success in Ising model, there were many puzzles. A few of them were: Can we use bootstrap technique to determine generic higher dimension CFTs? If so, which correlator should we bootstrap in order to determine a specific theory? Which condition should we impose? In this talk, I will address some of those questions. I will discuss how to use bootstrap techniques to compute quantities for 3D super-Ising and N=1 Wess-Zumino models. Those quantities themselves already imply interesting physics for the models. But more generally, the correlators and conditions we use can be understood by analyzing the state recombination based on the equation of motion. Our bootstrap strategy is systematic and can be applied to other theories.

Fei Teng (Uppsala University): SUSY decomposition and BCJ numerators from forward limits

Abstract: In this talk, I will introduce an efficient algorithm to write down n-point BCJ numerators for a variety of theories at tree level. These numerators are manifestly crossing symmetric and are given in a form suitable for a direct forward-limit construction of one-loop BCJ numerators. By allowing different matter contents running in the loop, we can achieve a SUSY decomposition. The well-known results of loop momentum power counting can be understood through the interplay between Lorentz traces and Dirac traces. Finally, I will present explicit results for maximal SUSY up to six external gluons, and discuss some future directions, like a recursive construction for arbitrary points, converting back to standard propagators, etc.

Congkao Wen (Queen Mary, UoL): Superamplitudes in six dimensions

Abstract: In this talk, I will review recent progress of twistor-like formulations of tree-level scattering amplitudes in a variety of six-dimensional supersymmetric theories. The theories of interest include the world-volume theories of probe single M5 brane and D5 brane, six-dimensional maximal supersymmetric Yang-Mills theory and supergravity, as well as supergravity with (2,0) supersymmetry. I will also briefly discuss their applications on the holographic correlators in AdS3xS3. 

Ye Yuan (Zhejiang University): Celestial OPE in Scattering Amplitudes

Abstract: I will make some preliminary discussions on the potential CFT interpretation of the Mellin transformed scattering amplitudes for massless particles, with a focus on the OPE of celestial operators.

Peng Zhao (ITP): Y-system polytopes and stringy integrals

In addition, on Jan 2 we will have a seminar by Yu-tin Huang on “Double copy of Electric-Magnetic dualities”, and on Jan 14 we we will have a seminar by Yang Zhang (USTC) on “Frontiers in multi-loop dimensionally regulated amplitudes with high multiplicity”. We will update this page with more information later (which can also be found at ITP webpage).


Song He (ITP)