Primordial nucleosynthesis and particle physics: I have shown how the long-lived relics, charged under strong or electromagnetic gauge groups, catalyze nuclear by forming bound states with nuclei. In particular, I have shown the possibility for the reduction of 7Li and enhancement of 6Li abundances relative to standard prediction, an intriguing pattern supported by observations. My results have serious implications for the collider searches of supersymmetric particles, where the long-lived charged objects are commonplace occurrence in models with gravitino as the lowest mass SUSY state. I will continue working in this direction as I am motivated by a rather serious discrepancy between the observed and detected lithium abundances.
Secluded models of dark matter. In 2007 Ritz, Voloshin and I pointed out the whole class of WIMP dark matter models that may escape direct detection in underground experiments or at colliders, but have indirect astrophysical signatures. This class of models can accommodate recent &quot;anomalies&quot; in cosmic rays in the 100 GeV domain without fine tuning, as the secluded models often have enhanced annihilation cross sections relative to usual WIMPs. Currently this is one of the most active research areas in astroparticle physics. Possible collider implication of model that we proposed is the sub-GeV vector and scalar resonances that are going to be searched for in the data accumulated by high-luminosity colliders and fixed target experiments. In somewhat related development, my collaborators and I have shown how the B-decays can be used to set stringent constraints on the low mass WIMPs. Overall, the secluded dark matter models together with searches of &quot;dark force&quot; represent a semi-infinite direction in particle physics towards luminosity frontier and I expect to keep active in this field.
B-modes of CMB from new infrared physics. Next five years will be years of active experimental search for the &quot;curl&quot; or B-modes of polarized cosmic microwave background. In 2008, Ritz, Skordis and I have shown that B-mode polarization may result from the inflation-generated fluctuations of the massless pseudoscalar field(s), often predicted by e.g. string theory models. This brings up an important and under-researched question of how to separate the effects of tensor modes, pseudoscalar modes, primordial magnetic field and lensing background, given likely observation of B-modes in the near future. I will continue developing this direction and explore the impact of other IR degrees of freedom on the CMB physics.
Other research directions include new infrared physics models that predict change of masses and couplings it time and space. My idea of environmental dependence of couplings and masses on ambient density stimulated new observational tests within our galaxy. I also study flavor and CP violating effects in new physics models, including supersymmetry. So far my efforts in particle physics were mostly concentrated on searches of new phenomena related to non-SM physics. This is &quot;high-risk/high-gain&quot; program, and in the future I will try to develop some more balanced approach and add some &quot;standard physics&quot; directions in my research. What precisely it is going to be remains to be seen...