Particles, Fields, Pomerons and Beyond
  This paper is a set of musings on what particles really are -- something one all too often as a particle physicist assumes is pretty well-established. The initial motivation for these thoughts comes from a question that I always ask Alberto Santoro whenever I see him which is "What exactly is a pomeron?". I argue that the concept of a particle that we normally have is really quite far from reality and that there could be deep physics in reconsidering very carefully exactly what we mean by particles. Perhaps one of the great coming challenges is not simply to "find more particles and measure their couplings" but to revisit the very concept itself of a particle, and that a good place to do this may well be very strongly interacting theories like QCD and in very forward scattering and the study of objects like pomerons. 
John Swain
hep-ph hep-th