Introduction

Astronomy & Astrophysics

• Daily Picture
• American Astronomical Society

Atomic, Molecular
& Optical Physics

• Atoms, Molecules,&Light
  National Academy Press

Condensed Matter &
Materials Physics

Particle Physics

Nuclear Physics

Space Physics

Facilities

• High Performance Computing
• Electron Microscopy

Elementary Particle Physics

Elementary particle physics is the field that attempts to discover the most fundamental consituents of matter, the forces by which they interact, and the laws that govern those forces. At present there is a theory of particles and their interactions which well describes physics down to distances less than a thousandth the size of a proton. However, this "Standard Model" leaves many questions unanswered.

Among these questions are why gravity is so much weaker than the other forces, why there are three families of every type of quark and lepton, why the weak interactions violate CP symmetry but the strong interactions conserve it, why the elementary particles have the intricate pattern of masses and mixing angles they do, how the particle-antiparticle asymmetry of the universe came about, and what kind of particles make up the universe's "dark matter". Recent discoveries such as neutrino oscillations and the existence of "dark energy" in the universe have raised new theoretical puzzles.

Much of the work carried out by the particle physics group involves the effort to go "beyond the Standard Model" to deeper theories that can answer these questions, such as supersymmetry, grand unified theories, and theories with "extra" dimensions of space.

Cosmology and astrophysics provide a window on high energy interactions and rare processes not yet accessible to particle accelerators. Delaware has a strong experimental and theoretical program in particle cosmology, high energy astrophyics, and cosmic ray physics.