The known elementary particles range in mass from about 0.0004eV for the lightest neutrino to around 170 billion eV = 1.7 x 10^11 for the heaviest quark, the top. This is a ratio of about 400,000,000,000,000 to 1.
On the other hand, the energy scale available from Einstein’s theory of gravitation (which relates mass to energy) [...]
Entries from May 2008
May 27, 2008
Planck Energy and Perturbation Theory
May 22, 2008
Mandelstam Variables and Veneziano Amplitudes
Quantum mechanics is a probabilistic theory. The probabilities are the squared magnitudes of (probability) amplitudes. Amplitudes are computed through perturbation theory, or whatever method one can find. The state of the art method is to use Feynman diagrams to find the amplitudes.
When one considers interactions between two particles, there are two Feynman diagrams that are [...]
May 12, 2008
Review: ‘t Hooft’s The Conceptual Basis of Quantum Field Theory
I should be preparing for my 10 minute lecture on classification of hadrons at the American Physical Society’s Northwest meeting on Saturday, but instead I am reading Gerard ‘t Hooft’s beautiful introduction to quantum field theory, The Conceptual Basis of Quantum Field Theory. I like the approach of this book because it concentrates on what [...]
