There are two workshops going on this week that you can follow on video, getting a good idea of the latest discussions going on at two different ends of the spectrum of particle theory in the US today.
At the KITP in Santa Barbara there’s Black Holes: Complementarity, Fuzz or Fire?. As far as I can tell, what’s being discussed is the black hole information paradox reborn. It all started with Joe Polchinski and others last year arguing that the consensus that AdS/CFT had solved this problem was wrong. See Polchinski’s talk for more of this argument from him.
If thinking about and discussing deep conceptual issues in physics without much in the way of mathematics is your cup of tea, this is for you (and so, I fear, not really for me). As a side benefit you get to argue about science-fiction scenarios of whether or not you’d get incinerated falling into a black hole, while throwing around the latest buzz-words: holography, entanglement, and quantum information. If you like trendy, and you don’t like either deep mathematics or the nuts and bolts of the experimental side of science, it doesn’t get much better than this. One place you can follow along the latest is John Preskill’s Twitter feed.
Over on the other coast, at the opposite intellectual extreme of the field, LHC phenomenologists are meeting at the Simons Center this week at a SUSY, Exotics and Reaction to Confronting Higgs workshop. They’re discussing very much those nuts and bolts, those of the current state of attempts to analyze LHC data for any signs of something other than the Standard Model. Matt Strassler is there, and he is providing summaries of the talks at his blog (see here and here) At this workshop, still no deep mathematics, but extremely serious engagement with experiment. One thing that’s apparent is that this field of phenomenology has become a much more sober business than a few years ago, pre-LHC, and pre-no evidence for SUSY. Back then workshops like this featured enthusiastic presentations about all the wonderful new particles, forces and dimensions the LHC was likely to find, with one of the big problems being discussed the “LHC inverse problem” of how people were going to disentangle all the complex new physics the LHC would discover. Things have definitely changed.
One anomaly at the SEARCH workshop was Arkani-Hamed’s talk on naturalness, which started off in a promising way as he said he would give a different talk than his recent ones, discussing various ideas about solving the naturalness problem (though they didn’t work, but might be inspirational). An hour later he was deep into the same generalities and historical analogies about naturalness as in other talks, headed into 15 minutes of promotion of anthropics and the multiverse. He ended his trademark 90 minute one-hour talk with a 15 minute or so discussion of a couple failed ideas about naturalness, and for these I’ll refer you to Matt here.
Arkani-Hamed and others then went into a panel discussion, with Patrick Meade introducing the panelists as having “different specialties, ranging from what we just heard to actually doing calculations and things like this.”
Update: Scott Aaronson now has a blog posting about the KITP workshop here.
Update: A summary of the situation from John Preskill is here.