We will have a Journal Club at 7pm, Tuesday, Oct 15 in the 19th-floor Observatory Hall. This Journal Club will be given by Ye Xuan (叶翾). The title of the talk will be "Adiabatic regularization and Green’s function of a scalar field in de Sitter space: Positive energy spectrum and no trace anomaly".

Xuan will present their recent paper, arXiv:1903.10115. In this talk, he will illustrate how the gravitational field combine with spin-0,1/2,1,2 field and give the basic formulas involving them. Four regularization methods will be also introduced, mainly on adiabatic regularization and point-splitting regularization. Finally, Xuan will talk about their recent work about how to regularize a scalar field in the de-Sitter space without ambiguity.

You are welcome to join the discussion. We will provide snacks and drinks.