“Is the title an oxymoron?” Harold Shapiro asked rhetorically at the beginning of his talk, The Responsible Use of Public Resources in Elementary Particle Physics. He wanted to show how one goes about prioritizing funding within the US science budget for high-energy physics. Later in his talk he posed another rhetorical question: “Are we in the US silently executing an exit strategy?”
Shapiro is professor of economics and public affairs at Princeton University and also chairs the US elementary particle physics committee. The committee is composed of nine particle physicists among five non-particle physicists and six non-physicists, and recently submitted a report recommending research priorities to the US National Academy.
The report begins by summarizing, for the uninitiated, the main unresolved issues in physics: the nature of space and time; the origin of mass; and the beginning and fate of the universe. Then it notes that the most likely way for significant progress to be made will be to resolve Einstein’s theory of general relativity, which describes how gravity arises from the curvature of space–time, with the Standard Model of particle physics. A theory known as supersymmetry might be able to do this, but to be tested it really needs the help of particle accelerators that operate at tera-eV (1012 eV) energy scales.
One such accelerator is the Large Hadron Collider (LHC) at CERN, due to start-up this June. However, it ought to be complemented by the International Linear Collider (ILC), a non-hadron accelerator that is still in the R&D stage. The US would like to submit a credible bid to host the ILC, and that requires making significant R&D contributions. Hence firmly recommending it as a priority to the National Academy.
Trouble is, particle accelerators are expensive pieces of kit. The LHC will clock-in at around $9.2bn, while the ILC could easily be double or triple that. Playing the devil’s advocate, I asked why funds allocated for particle-physics facilities would not be better spent on research into more useful physics — alternative energy, for instance. Shapiro said there is no way of quantifying which is more important, adding that, for him, understanding the ways of the universe “is an extraordinarily important issue.”
Lawrence Krauss of Case Western Reserve University, the symposium organizer, also chipped in. “There is no other way of answering these big questions,” he said. “And it’s worth remembering that the entire cost of the LHC is the same as nine days in Iraq.”