[4][5] He currently holds a professor position at the Simons Center for Geometry and Physics[6] at Stony Brook University in New York.
[8] Cardy's conjecture was a generalization of the c-theorem by Alexander Zamolodchikov (1986)[9] for two-dimensional quantum field theories on higher dimensions.
The c-theorem ensures the existence of a function that decreases monotonically with the flow of the renormalization group (RG) (a function of the coupling constants and energy scale), which assumes constant values independent of the energy scale at the fixed points of the RG.
The theorem also makes statements about the number of degrees of freedom in quantum field theory depending on the energy scale.
In 1988 Cardy[10] proposed the existence of an analog function (a-function, as an integral of the expected value of the trace of the energy-momentum tensor over the four-dimensional sphere) in four dimensions.