دانلود کتاب کشف بوزون هیگز در برخورد دهنده بزرگ هادرون

The theory to describe all fundamental constituents ofmatter and their interactions is the StandardModel of Particle Physics (SM) [1–3]. It is a Lorentz covariant quantum field theory and as such a multi-particle theory, with operators for particle creation and destruction. It is capable not only of explaining the dynamics of elementary particles but also transitions from one particle into another, particle decays, particle annihilation or the production of new particles out of the quantum vacuum, which corresponds to the energy ground state of the theory. In quantum mechanics particles are categorized into bosons (with integer spin) and fermions (with half integer spin). In multi-particle environments both groups of particles have a distinct behavior:while bosons share the same phasespace, which allows for a description of their dynamics in a single, space-symmetric wave function, fermions always occupy a unique element in a multi-particle phasespace, which can never be shared with any other fermion at the same time. This fact is expressed by the exclusion principle of Wolfgang Pauli [4]. Fermions, in contrast to bosons, are described by wave functions which are anti-symmetric in their space coordinates. The behavior of multi-particle systems made of fermions or bosons follows the Fermi or Bose-Einstein statistics, which hold for all fundamental, non-divisible particles that we know so far, as well as for more complex composite objects that still need to be treated on a quantum mechanical basis, like atoms or molecules. Nowadays, the particle physics experiments have the ability to analyze structures at distances as small as 10−19 cm, corresponding to a sub-per mill of the size of the proton. To our understanding, all matter that we know is made up of quarks and leptons, which both are fermions, with spin 1/2. Both kinds of particles have been found to lack further structure (i.e. they are not made up of even more fundamental particles), to be non-divisible and point-like up to the current level of accuracy. To our current knowledge we can assign four fundamental forces to govern all interactions between them which are mediated by the exchange of bosonic particles: gravitation, the electromagnetic, weak and strong force. Each of these forces will be briefly discussed in the following paragraphs.