Sinha specialised in nuclear physics, high energy physics, quark–gluon plasma and early universe cosmology. He is credited with helping India achieve recognition in the global science community. He contributed to making India join the search for the Higgs boson at CERN, helping the search that lasted from 2008 to 2012, which eventually culminated with the discovery of the Higgs boson. At CERN he also worked in creating and researching quark–gluon plasma alongside searching for the Higgs Boson. Sinha additionally led his team to do experiments at the Relativistic Heavy Ion Collider at the Brookhaven National Laboratory in the US and the Facility for Antiproton and Ion Research in Germany.