We revisit Minkowski's lost legacy on relativistic electromagnetism in order to resolve long-standing puzzles over the charge distribution of systems like hadrons. Hadrons are unique electromagnetic characterized by their comparable size and Compton wavelength rh∼λC. As such, it was recently realized that traditional Sachs definition based a non-relativistic formula is invalid. explain this sam...

IFFERENCES between reciprocal hybrids of strains of various animals D are not uncommon. In the house mouse an example is the incidence of spontaneous mammary cancer in crosses between “ high incidence ” and ‘* low incidence” strains (MURRAY and LITTLE 1935). When it may be assumed that the cause of the differences between the reciprocal hybrids is not genetic, as in matings between inbred strai...

In this paper, we examine the Dirac monopole in the framework of Off-Shell Electromagnetism, the five dimensional U(1) gauge theory associated with StueckelbergSchrodinger relativistic quantum theory. After reviewing the Dirac model in four dimensions, we show that the structure of the five dimensional theory prevents a natural generalization of the Dirac monopole, since the theory is not symme...

The extensions of GR for description of fermions on a curved space, for supergravity, and for the loop quantum gravity ordinary use a set of 16 independent variables instead of 10 components of metric. These variables can be assembled in a coframe field, i.e., a set of four linearly independent 1-forms. In this presentation we review a geometrical structure based on the coframe field. We constr...

Richard Feynman has claimed that anti-particles are nothing but particles ‘propagating backwards in time’; that time reversing a particle state always turns it into the corresponding anti-particle state. According to standard quantum field theory textbooks this is not so: time reversal does not turn particles into anti-particles. Feynman’s view is interesting because, in particular, it suggests...

We present a sequence of activities designed to stimulate students reflect on the nature light and different models (ray, wave, classical quantum particles) used in teaching learning optics. These are also aimed help evaluating profound meaning "correspondence principle" develop their own views about some aspects science even if it is not taught explicitly. In fact, optics paradigmatic case whe...