Two photons colliding with each other can form a particle and an antiparticle. But what happens to the original “light information” that these two photons originally “possessed”. Conversely, the particles and antiparticles formed can re-form photons upon anihilation.
Answer
Dear Stefan,
That depends on what exactly you mean by ‘light information’. By your question do you mean: from the observation of the individual angular momentum and energy of a produced pair of ‘particle’ – ‘anti-particle’ can you infer the individual angular momentum and energies of the original photons?
The answer is that the total impulse moment and energy is conserved. The energies of the individual photons can be calculated. The angular momentum of the individual photons cannot be calculated if you assume point particles or use a quantum mechanical model. The angle between the relative angular momentum of the photons and the pair of particles follows a random distribution that is uniform when the photons collide straight against each other with opposite velocities.
Answered by
ir. bruno Bauwens
Computer Sciences
http://www.ugent.be
.