5 papers
Anomaly inflow and -form gauge theories
Chang-Tse Hsieh, Yuji Tachikawa, Kazuya Yonekura
Chiral and non-chiral -form gauge fields have gravitational anomalies and anomalies of Green-Schwarz type. This means that they are most naturally realized as the boundary modes…
Anderson duality of topological modular forms and its differential-geometric manifestations
Yuji Tachikawa, Mayuko Yamashita
We construct and study a morphism of spectra implementing the Anderson duality of topological modular forms (). Its differential version will then be introduced, allo…
N=2 supersymmetric dynamics for pedestrians
Yuji Tachikawa
We give a pedagogical introduction to the dynamics of N=2 supersymmetric systems in four dimensions. The topic ranges from the Lagrangian and the Seiberg-Witten solutions of SU(2)…
Undecidable problems in quantum field theory
Yuji Tachikawa
We point out that some questions in quantum field theory are undecidable in a precise mathematical sense. More concretely, it will be demonstrated that there is no algorithm answer…
Remarks on mod-2 elliptic genus
Yuji Tachikawa, Mayuko Yamashita, Kazuya Yonekura
For physicists: For supersymmetric quantum mechanics, there are cases when a mod-2 Witten index can be defined, even when a more ordinary -valued Witten index vanishes.…