Tag Archives: talk

Talk: Extragalactic B-fields from Gamma Rays

Speaker: Tom Weisgarber (Chicago)
  • Voids: <1nG; filaments: ~0.3 µG; galaxies: ~1 µG; clusters: 10 µG.  No detections of B-fields in voids.
  • Gamma rays interact with the extragalactic background light (EBL) and create electron-positron pairs, which then cascade down to create more gamma rays. This cascade is then observed with some opening angle.  Pair production and inverse Compton … Continue Reading ››

Talk: GRBs – Recent developments from Fermi

Peter Mészáros (PSU)
  • Are the photons from leptonic or hadronic origin?  X-ray to radio: leptonic, MeV: probably leptonic; GeV: debated.
  • GRBs are a possible origin for ultra-high energy cosmic rays.  For gravitational waves, theoretically but not detected yet.
  • GRB 080916c: Adbo+ (2009, Science, 323, 1688): GeV photons "lag" behind MeV photons.  Why?
  • (Jacob & Piran 2008): Quantum gravity?  Energy-dependent … Continue Reading ››

GPU Meeting (04 Oct 2011)

Lionel London (CRA) – GPU Computing in Matlab
  • Matlab Parallel Computing Toolbox (PCT) vs. Jacket
  • PCT allows for multi-cpu and GPU computing. Limited to 12 cores on the local machine. Very high level.
  • GPU computing with PCT requires an nVidia card with v1.3 compute capabilities. GPGPU with Jacket has relaxed requirements but is very expensive ($4k for 5 … Continue Reading ››

Discussion: Doing Science in the Open

Michael Nielsen Yesterday I attended a discussion with Michael Nielsen and the GT faculty, where open science was the subject.  We covered various venues for promoting collaborative science projects.  Some were completely new to me.  Let's cover a few examples that were discussed.


The ASSET India Foundation aims to educate and provide better opportunities for … Continue Reading ››