The Reverend Doctor Bob's Home Page

Bob McElrath
435 Physics/Geology
University of California, Davis
Davis, CA 95616
office phone: 530-752-0820
email: my first name @ my last name . org
Jabber, AIM, MSN, Yahoo Messenger, IRC: bsm117532

I am a Post-Doctoral Researcher (aka PGR) at the University of California, Davis Physics Department. I am an avid user and contributor to open-source software especially Linux and the Debian Project. I keep a LaTeX-enabled Wiki, my Notes that contains notes and ramblings of a physics nature. The SPIRES database is the best place to find an up-to-date list of my professional publications. I maintain and for my own use and the use of members of my family (and any other poor sod with the last name "McElrath"). I am an avid space nut and hope to someday get my butt on Mars.
Other pages of interest:

Research Interests


I believe that first and foremost, physics exists because of experiment. Theory is only useful so long as it can explain or predict phenomena. As such, all my work has been, and will continue to be directly related to experiments that can be performed in the near future. Any way I can assist experimentalists is in my mind the most important contribution I can make. For example, I have been actively communicating with experimentalists at BaBar regarding my recent light dark matter papers, and experimentalists at Davis on CMS and CDF regarding Higgs searches. I have extensive experience with high-energy experiments, having worked on D0 (under Heidi Schellman), ALEPH, and BaBar (under Sau Lan Wu) early in my career. This makes me an effective go-between for theory and experiment, and I will use this to my advantage in the LHC era.

Higgs and electroweak symmetry breaking

With the planned startup date of the LHC being 2007, the LHC will most likely begin taking data while I am a post-doc at your institution. As the highest energy collider operating, it will have a window into the mechanism of electroweak symmetry breaking and mass. It is of the utmost importance that we are prepared to find whatever the LHC presents to us. I will continue to pursue detailed collider studies that can reveal the nature of electroweak symmetry breaking and the origin of mass. I am actively participating in the CP-Violating and Non-Standard Higgs (CPNSH) working group, to help chart the landscape of things that might be seen at the LHC. An important upcoming contribution in this area is Higgs-to-Higgs decays, which have been largely overlooked by existing studies, and will require clever techniques to discover. These decays exist in almost every extended model, and should be pursued both theoretically and experimentally.

Dark Matter

As a field, the experimental study of dark matter has been plagued by model-dependence. The community expects the MSSM to be correct, and is not expending very much effort trying to discover alternatives. Any new physical phenomena must be approached from a model-independent perspective, in order to assure discovery. All regions of parameter space that are experimentally accessible should be investigated. With my two recent papers about dark matter I have suggested new and overlooked measurements that cover ignored parts of the parameter space, that can be done at existing B-factories.

Hierarchy Problems

Quantum Field Theory and String Theory have both been spectacular failures at explaining the apparent discrepancy between the Planck scale and the electroweak scale. What's worse is that if the solution does lie in high energy phenomena (e.g. String Theory), we might {\it never} discover it. I believe that the answer does not lie in the high energy theory at all, and solutions should be sought in low-energy dynamics. A possible solution is that field theory is renormalizable to arbitrarily high energies (e.g. gravity does not provide a cutoff to field theory), and gravity arises as an effective theory. The amazing numeric coincidence between the MOND scale, Hubble expansion rate, and Pioneer Anomaly are too suspicious to ignore, and all seem to point to the same scale as the source of the necessary dynamics to explain them. This naturally makes contact with neutrinos, as the cosmological constant is at the same scale as the neutrino mass. The means by which this may occur was first suggested by Unruh, that the vacuum may actually be a condensate.


When I'm not doing geeky things I also like to run, hike, bike, backpack, and generally be outdoors.