Research Interests

I am a researcher at the field of theoretical cosmology. My work so far has focused on the investigation of various research topics in cosmic microwave background (CMB) physics. I am interested in aspects of both the primary and secondary CMB signals and, more generally, in the field of particle cosmology; signatures that can be probed by observable properties of the CMB, in particular.

The CMB can be viewed as an experiment that has been in operation for the entire 14 billion years history of the expanding universe, and it is only here and now that we harvest and decode the data. The CMB, often supplemented by other cosmological probes, has already proved as a distinctively powerful probe of certain key cosmological parameters such as the energy composition and spatial curvature of the universe, and its reionization history. With the measurement recently announced by the BICEP2 team of B-mode polarization on horizon scales, the energy scale associated with cosmic inflation has been pinpointed at around the grand unification theory (GUT) scale. These exciting news came shortly after the first B-mode detection on sub-degree scales by the POLARBEAR (PB) team. The latter signal was induced via lensing of the dominant E-mode polarization by the intervening large scale structure and can potentionally inform us about, e.g. the sum of neutrino masses, dark energy, and curvature .

It also has the potential to address issues of more fundamental nature, such as the degree of lepton asymmetry in the early universe, validity of the CPT and parity symmetries (manifested as `cosmological birefringence' in the CMB), and potentially even put to test the cosmological principle.

It is an active field of research that draws together both theoreticians, experimentalists and phenomenologists, astrophysicists as well as particle physicists, in pursuing the valuable information encrypted in the feeble CMB temperature and polarization anisotropy at recombination, when the CMB photons decoupled from the plasma, approximately 400,000 years after the big bang (primary CMB), and later, a few billion years ago (secondary CMB) via lensing of the CMB by dark matter halos, and comptonization of the CMB by the hot intracluster (IC) gas in galaxy clusters, the Sunyaev-Zeldovich effect.

With the wealth of high-quality data we expect to have in the near future from CMB experiments (such as the PLANCK satellite as well as many powerful ground-based and baloon-borne CMB telescopes and data from other cosmological probes) we hope to perhaps unlock some of the deepest mysteries of the initial conditions of the universe and the laws of nature.

Meir Shimon

Contact

DEPARTMENT of ASTROPHYSICS
FACULTY OF EXACT SCIENCES
Tel Aviv University
Ramat Aviv, Tel Aviv
69978 Israel

Kaplun - Physics Building, room 517
Tel: (972)-3-6407414
Fax: (972)-3-6408179
Email: meirs[at]wise.tau.ac.il