Particle physicists in the United States, aiming to organize their thinking and make it easier to explain their views to each other and to the outside world, meet every few years in workshops to consider the future of the field. (Something like this is done in a number of other scientific fields as well.) Right now, particle physics is commonly described as pursuing three general research directions:
- The Energy Frontier: Try to make new heavy particles or other high-energy phenomena using very high-energy high-collision-rate accelerators (such as the Large Hadron Collider)
- The Cosmic Frontier: Let the Universe itself, through its natural particle production mechanisms, teach us something (through properties of “dark energy” or dark matter or through cosmic rays, etc.)
- The Intensity Frontier: Search for rare new phenomena or difficult-to-produce new particles using medium-energy ultra-high-collision-rate accelerators, or some other low-energy ultra-high-rate mechanism.
With the U.S. currently out of the business of the Energy Frontier (the Tevatron having closed and there being no plans for future accelerators here) the Department of Energy has recently asked the U.S. particle physics community to hold a large workshop on the Intensity Frontier, to bring its goals into focus.
A meeting associated with this effort is going on today through Friday, in Washington D.C. About 500 scientists from different subfields of particle physics (and also some from nuclear physics) are gathered together. The difference between a “conference” and a “workshop” is that at the latter, new work is supposed to get done, both during the meeting and back home after the meeting is over. In this case, the outcome of this effort is to include a large summary document that will serve to guide scientists, the Department of Energy, the National Science Foundation and Congress as it is decided how to spend tax-payer dollars in the best interest of the U.S. and its scientific program.
For the purpose of this workshop, the Intensity Frontier has been divided into 6 subjects:
- Heavy Quarks
- Charged Leptons
- Neutrinos
- New Particles that Interact Extremely Weakly With Known Particles
- Proton Decay
- Nucleons, Nuclei and Atoms
If time permits I’ll explain later what the main concerns are for each of these subjects.
This morning I was listening to a set of very nice overview talks, one for each subject, by some of my famous colleagues: Nima Arkani-Hamed of the Institute for Advanced Study, Kaustubh Agashe of the University of Maryland, Kate Scholberg of Duke University, Neal Weiner of New York University, Bill Marciano of Brookhaven National Laboratory, and Michael Ramsey-Musolf of the University of Wisconsin. This afternoon and tomorrow, the six corresponding “working groups” are meeting separately, exchanging and discussing ideas and results. I’ll be in the working group that I called “New Particles That Interact Extremely Weakly With Known Particles.” [The official title is “Hidden Sector Photons, Axions and Weakly-Interacting Scalar Particles” but I don’t like the title because I feel it is far too limited…] On Friday the status of the working groups will be summarized, and I may be able to provide an update at that point, time permitting.
8 Responses
What might the next generation of particle accelerators look like and when might we expect one? I have not heard about anything that will just be a more powerful version of the LHC; it seems like we might move to a different type of accelerator not to something more powerful like we have in the past. The LHC has just gotten started, but I’m already thinking about what’s next.
This question doesn’t have a simple answer. There are many types of accelerators now and there will be many types in future. And what we build may well depend on what the current set of machines discovers or does not discover.
I seem to remember that 5 to 6 years ago there was much interest in using high power lasers to accelerate particles with some sort of wake effect. Supposedly these systems could be built in much more compact configurations than large circular conventional colliders. Any thoughts and will this be addressed at the conference in any substantial way.
These ideas have been around since I was a graduate student and before that too. Needless to say, progress … has … been … disappointingly … slow.
Matt—I’ve just heard that there will be talks by atlas and cms, 30 minutes each, on the 5 inverse femtobarn Higgs results. Talks will be in two weeks, around the time of the CERN Council meeting. Have you heard about this?
There are rumors to this effect, yes. There are rumors as well that contradict some or all of these statements.
I recognize that this question leaves the realm of theoretical physics for engineering (or science fiction!) but how easy would it be to create very high intensity neutrino beams, if you built a specialized machine just for that? Could you build them with a bit more coherence in direction than the OPERA apparatus? I’m asking because it might be interesting to build a very high-speed communication system — there are new cables being laid across the country and the Atlantic to speed financial communication; but clearly they are bound by the speed of light around the curvature of the earth — if we could send signals in a straight line, potentially faster than light…think of the arbitrage possibilities!
Certainly neutrino beams of huge intensity [compared to today’s beams — already very intense from many points of view] are possible down the line. They would be very expensive (I don’t think they would pay for themselves via arbitrage!) and the technology isn’t mature, but there’s no obstruction in principle. Long before then, it will be interesting to learn about the earth’s geology using strong beams that cross the earth. Maybe oil companies, or countries looking for resources, will help fund them? I have no guesses about the time scale for that; you need experts for that, and I suspect they would tell you they have no idea either. It won’t be 10 years, and it probably won’t be 20, but that could depend on how much people want to spend on it and how technology develops.