(a) Possible overproduction of primordial black holes is examined in the context of the original Higgs inflationary scenario, with the inclusion of renormalisation group effects.

(b) The speaker investigates multi-field signatures of the nonminimally coupled supersymmetric Higgs inflation-type cosmological scenario, focusing on the two-field Higgs-lepton inflation model as a concrete example. This type of inflationary model is realised in a theory beyond the Standard Model embedded in supergravity with a noncanonical K\"{a}hler potential. He analyses the bispectrum of the primordial fluctuations when the inflaton trajectory deviates from a straight line, and obtains constraints on the noncanonical terms of the K\"{a}hler potential using the Planck satellite data.

(c) The speaker examines the Higgs inflation in the presence of higher-dimensional operators. In particular he introduces Ricci scalar squared term in addition to the ordinary nonminimal coupling term and test the viability of the model.