Particle Theory

The central theme of the theoretical physics research in Hawaii is the exploration of different ways in which the Standard Model (SM) of particle physics may be extended, and how these various extensions would manifest themselves in various experiments, either at high energy colliders or at non-accelerator facilities. The interests of the members of the Group span a wide range of topics in particle physics phenomenology including, neutrino physics, CP violation, heavy quark systems, precision calculations in quantum field theory, supersymmetry, grand unification, implications of extra spatial dimensions, and other ideas for physics beyond the Standard Model, and the implications of particle physics for cosmology and astrophysics. They interact vigorously with one another as well as with their experimental colleagues in Hawaii , and over the years have formed wide-ranging and long-term collaborations with scientists at other institutions, both in the USA as well as abroad. The visibility of the Theory research program may be judged by the fact that the Group members are regularly invited to describe their research results at international conferences as well as to lecture at particle physics summer schools world-wide.

Theory Faculty

• Kirill Melnikov
  Melnikov is one of the leading experts on the application of quantum field theory to particle physics phenomenology. He is a versatile researcher whose contributions encompass a wide range including: radiative corrections in quantum electrodynamics (with recent applications to positronium), three loop QCD corrections to quark masses, studies of the tt system near threshold at linear e+e- colliders, QCD corrections to Higgs boson production at hadron colliders, heavy quark physics, lattice perturbation theory, the anomalous magnetic moment of the muon. He is currently working on developing new techniques that will enable calculations of great importance for LHC physics that, despite ever-increasing computer power, are intractable by current methods.
  
• Sandip Pakvasa
  Pakvasa is a recognized expert on neutrino physics and astrophysics as well as the phenomenology of CP violation. Together with Hirotaka Sugawara, he co-authored what is probably the first paper on the examination of the phenomenology of the now text-book Kobayashi-Maskawa model. His many seminal suggestions for models of neutrino masses and mixing, which include the celebrated bimaximal neutrino-mixing matrix, have received much attention from both the theoretical and experimental communities.
  
• Xerxes Tata
  Tata has been a leader in the development of strategies for the detection and elucidation of different new physics scenarios at high energy colliders, with a strong emphasis on supersymmetry, a novel symmetry that, unlike any other symmetry, relates the properties of bosons and fermions, providing a new level of synthesis. Most recently, he has been exploring the implications of the hypothesis that the cosmological dark matter (whose density has now been determined to a few percent) is predominantly the lightest supersymmetric particles left over from the Big Bang, and is working on how this may be tested by combining accelerator data with information from various dark matter detection experiments.

Other faculty members:

• Walter Simmons, Affiliate Faculty
• San Fu Tuan, Emeritus Faculty

Post-doctoral researchers:

• Achilleas Lazopoulos, Post-Doc
• Rahul Malhotra, Junior Researcher

Graduate Students:

• Sandip Biswas
• Andrew Box
• Roger Kadala

Publications:

• Kirill Melnikov
• Sandip Pakvasa
• Xerxes Tata
• Walter Simmons
• San Fu Tuan