The production and study of particles through deep inelastic scattering is one of the main tools in high energy physics and has led to a comprehensive understanding of the fundamental particles and interactions up to the electroweak energy scale. Successful running of the HERA ep collider, √ s = 319 GeV, has recently come to an end, and selected results are already available from the complete 1...

The “Standard Model” of elementary particle physics encompasses the progress that has been made in the past half-century in understanding the weak, electromagnetic, and strong interactions. The name was apparently bestowed by my Ph. D. thesis advisor, Sam B. Treiman, whose dedication to particle physics kindled the light for so many of his students during those times of experimental and theoret...

In these lectures on the early Universe I will discuss some recent developments in particle cosmology, taking particular care to highlight the r^ ole of particle physics in our understanding of cosmology. I will assume that the reader is familiar with basic particle physics, but not necessarily basic astronomy. Before starting, I would like to discuss the motivation for particle physicists to b...

Contact interactions offer a general framework for describing a new interaction with a scale above the energy scale probed. These interactions can occur if the StandardModel particles are composite or if new heavy particles are exchanged. The discovery potential of contact interactions at the LHC in dimuon and dijet final states at startup and the asymptotic reach are presented. PACS. 12.60.Rc ...

The Yang-Mills theory lies at the heart of our understanding of elementary particle interactions. For the strong nuclear forces, we must understand this theory in the strong coupling regime. The primary technique for this is the lattice. While basically an ultraviolet regulator, the lattice avoids the use of a perturbative expansion. I discuss some of the historical circumstances that drove us ...

In general, a physical system consists of a finite or infinite number of degrees of freedom which may or may not interact. The dynamics is prescribed by a set of evolution equations which follow from varying the action with respect to the different degrees of freedom. A symmetry then corresponds to a group of transformations on the space time coordinates and/or the degrees of freedom that leave...

The results presented at the 28th International Cosmic Ray Conference on neutrino and muon physics are summarized. Neutrinos and muons provide a huge amount of information on particle interactions up to very high energies and on fundamental particle properties. Results on neutrino oscillations in the atmospheric and solar ν sectors are summarized. Oscillations are well established in both secto...

The study of two spin asymmetries in hadron-hadron collisions probes the details of fundamental particle interactions in ways infeasible to machines with unpolarized collisions. Within reach is how the proton spin is distributed among its constituents through ∆G and ∆q̄. Measuring couplings, furthering our understanding jet structure and uncovering new physics are all among the possibilities ava...

INTRODUCTION This work is the overview of experimental results on the investigation of photon interactions obtained at LEP. The generalized diagram of the reaction (e + e – e + e – + X) is shown in Fig. 1 [1]. Incident electrons 1 emit virtual photons which due to the uncertainty principle fluctuate to some intermediate state: / pair or quark–gluon system. The two-photon interaction can be repr...

String theory is a physical model that represents elementary particles by vibrating strings with the aim of unifying the four forces of nature (gravitational, electromagnetic, strong nuclear, and weak nuclear). As a closed string (i.e a loop) moves through space, it may split into two (corresponding to fission), which may later recombine into one (corresponding to fusion). The path traced by a ...