Origin of Cosmic Rays

Recently I wrote a note "On the Origin of Ultra High Energy Cosmic Rays", here I present some ideas about this topic.

An important issue is, How they get their energies? Obviously the higher the energy the more difficult is to find a physical process to explain the data.

Many years ago Enrico Fermi proposed that random kicks by electromagnetic fields accelerate them. At first it seems unlikely that random processes could achieve such high energies as are observed. What will make the next kick come just in time to increase instead of decrease the energy? As it happens there is no need of hindsight by a designer to organize the coincidence. There is self-organization in non-linear systems. Even a simple kicked harmonic oscillator in one dimension shows a level of order difficult to see in our minds before these structures start to appear in the computer monitors for simulations. As if by magic one sees pentagons on the screen, if the period of the kicks is one fifth of a period. This is called random walk. Graphing position and momentum on the same screen a web appears taking the particles to higher and higher energies in a random way.

Nowadays for the highest energy particles observed by the Pierre Auger Observatory, the preferred models are Active Galactic Nuclei in the center of nearby galaxies. The concentrated masses of several hundred million times the solar mass available in those places, and magnetic fields of a hundred thousand Gauss or more. But what if on top of those huge energy concentrations, one appeals to the self organizing properties of matter? The synchronicity of the response in the stochastic process is an emergent property, it is not designed by the previous conditions. There is an element of disorder that produces order not existing before. Order out of chaos.

We have to put everything on the plate, this seems to be a hard problem.