COLLABORATION IN BASIC SCIENCE AND ENGINEERING (COBASE)

Arthur Kosowsky and his Georgian colleague Tinatin Kahniashvili of the Abastumani Astrophysical Observatory in Tbilisi spent January to July 2000 pursuing their collaborative studies in theoretical cosmology with support from a COBASE Long-Term grant. During the visit to Rutgers, which was Kahniashvili’s first to the United States, the two researchers initially focused on the calculation of gravitational radiation derived from turbulence in the early universe. Working with Kosowsky’s graduate student, Andrew Mack, they produced a large number of calculations comprising the only systematic treatment of the primordial magnetic field and the cosmic background radiation, including all relevant effects and special cases. Their results are summarized in two lengthy papers soon to be submitted for publication, one describing the calculations for scalar perturbations and the second for vector and tensor perturbations.

Work on the primary topic of their research led to an interesting related insight, namely that the predominant source of gravitational radiation might not be from the turbulence itself, but rather from the magnetic fields generated by the turbulence through a dynamo mechanism. This led to a second area of work aimed at producing detailed analytical calculations of primordial magnetic field influence on Cosmic Microwave Background temperature and polarization anisotropies.

As a result of the visit, Mack had the opportunity to attend an astrophysics conference in Tbilisi in September 2000, and Kosowsky plans to present their research results at a workshop at Drexel University later in October. During her visit, Kahniashvili was also able to participate in a conference at the Harvard-Smithsonian Center for Astrophysics and present a seminar at Michigan State University. She has also made presentations at a conference in Switzerland and two workshops in Georgia, and she reports that she has incorporated her U.S. research experience into her lectures at the Tbilisi School of Cosmology. Plans are set for her to make a month-long return visit to Rutgers in early 2001 to finalize publications and discuss future collaborative projects.