Generalized Uncertainty Principle, Black Hole Remnants, and Dark Matter


Date Thursday August 5th 2004
Time 4:00-5:00pm
Venue George E. Pake Auditorium

PARC Forum

It is by now widely accepted that dark matter (DM) constitutes a substantial fraction of the present critical energy density in the universe. However, the nature of DM remains an open problem. One interesting candidate is the Planck-size black hole remnants generated in the early universe. I’ll first give a pedagogical and elementary introduction of modern cosmology, general relativity and quantum mechanics. I’ll then introduce the generalized uncertainty principle, and based on that the augement for the existence of black hole remnants. Basic notions of cosmic inflation is then introduced and, taking hybrid inflation model as an example, the required abundance of BHRs as DM is demonstrated. Possible experimental signatures for the detection of BHR are discussed.


Dr. Pisin Chen received his Ph.D. in theoretical particle physics at UCLA. Since 1986 to present, he has been associated with the Stanford Linear Accelerator Center at Stanford University, where he is currently the leader of a particle astrophysics and cosmology group. He is internationally recognized for his co-invention of the "plasma wakefield accelerator" concept (1985) and the invention of the "plasma lens" concept (1987). In the late 1980s and early 1990s, he focused his research on "beamstrahlung", a novel nonlinear quantum electrodynamic (QED) phenomenon, in linear colliders. He was recognized for his discovery of the "beamstrahlung coherent pair creation" effect in 1989. For these contributions, he was elected as a Fellow of the American Physical Society in 1993. Since 1992, his research interest shifted to particle astrophysics and cosmology. He is a two-time recipient of the Gravity Research Foundation Essay Competition Awards (1995 and 2001). He is one of the original proponents of "laboratory astrophysics" using high intensity laser and particle beams. His current research interests on the theoretical side are the nature of dark matter and dark energy, and on the experimental side, laboratory astrophysics and particle astrophysics. He was the spokesperson of the international Plasma Lens Collaboration (1995-2000) and is currently a co-spokesperson of the "Fluorescence in Air from Showers (FLASH)" experiment at SLAC, which aims at resolving an important existing discrepancy in ultra high energy cosmic ray detections.

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