Ashtekar and re-understanding the Bang

[Martin]

Ashtekar (born 1949 in Maharashtra) is a key person in the current process of re-understanding the Big Bang. We should know about both the person and the ongoing research progress, involving many others as well, in which he plays an important role. So here are some links and random details.

 

Here's a 1999 profile by a NYU journalism grad student (human detail: childhood, family, career-start, mentors, friends,...)

 

http://us.rediff.com/news/1999/may/15us2.htm

http://us.rediff.com/news/1999/may/15us3.htm

http://us.rediff.com/news/1999/may/15us4.htm

http://us.rediff.com/news/1999/may/15us5.htm

 

Here's the CV at his website:

http://www.gravity.psu.edu/people/Ashtekar/cv.html

 

In 1992 Penn State wanted to get him to come there so they established a special institute for him to be director of, the Institute for Gravitational Physics and Geometry. Last year the institute was upgraded and broadened to the Institute for Gravitation and the Cosmos (IGC) which he leads. The guy has a tribe of intellectual offspring---people he has mentored: who got their PhDs under his guidance or worked for him as postdocs---who have spread out to other institutions.

 

The basic point is that vintage 1915 Gen Rel dies a gory death at the putative Big Bang. Everybody was unhappy with that so in the late 1960s Wheeler and DeWitt (WDW) came up with Quantum Cosmology Version 1.0 in hopes that it would not blow up and would extend understanding back past the failure-point. But the WDW model also blew up, Version 1.0 failed. People tried various things, but the field stalled in the 1980s. Then somewhere around 1999-2001 it took off again. Ashtekar was part of that---another pivotal figure, Martin Bojowald, was an Ashtekar postdoc at Penn State at the time. Ashtekar gradually took over a guiding role in Quantum Cosmology Version 2.0. Since 2005 there has been a flood of new papers and a rush of researchers into the field. There must be 50 people now doing Ashtekar-style quantum cosmo. A key issue is testability. A fair amount of recent work, just looking at papers that have appeared since June 2008, is about finding ways to test nonsingular (bounce) QC by observing early universe structure formation and the detailed temperature fluctuation in the microwave background----also about possible signature in gravitational wave background, were this to be detected. Testability is an important issue, so if you want links to recent papers please ask!

 

Ashtekar is the secondgeneration descendant of John Archibald Wheeler (of Version 1.0). Ashtekar's PhD (1974) advisor was Robert Geroch at Chicago and Geroch's PhD (1967) advisor was Wheeler at Princeton. Geneology , bloodlines. As his most important mentors, Ashtekar lists Nobel astrophysicist Chandrasekhar (who was at Chicago when A. was a grad student there), Geroch, and Roger Penrose (with whom he became friends as a postdoc at Oxford).

 

I've got more to say e.g. regarding the putative Bang and the elimination of the singularity in modern QC, but I'd prefer not to make individual posts too long---they get hard to read. So please comment. It breaks up the posts and helps the flow of ideas. Otherwise I have to wait 3 days or so before the system allows a post-break.

Edited November 3, 2008 by Martin

[npts2020]

Unfortunately, I moved from State College in 1989 and only got to hear second hand about the events you describe surrounding Mr. Ashtekar. Isn't it amazing with all of the advancements and good news in the world, how little of it you actually find out about without searching for it?