- #1
Alfredo Tifi
- 68
- 4
A monochromatic gamma light source S emits photons with spherical symmetry. These photons have a little less energy than necessary to permit formation of particle - antiparticle couples (electron-positron couple) or “EPCs”. An inertial observer O moves towards S with a small fraction of light speed. O carries an experimental apparatus to detect EPCs. Due to relativistic Doppler effect his velocity is high enough to experiment blue-shifted photons arriving from the source, with a significant probability to create EPCs, which are eventually detected. Once O passes beyond S, getting farther and farther from it, he just sees red shifted gamma rays without any EPC creation event detected.
So, how can a phenomenon-event occur relatively to O for half trip while not occurring for the second half trip and from S’s POV? The photons don’t “know” who are watching at them!
PS the experimental apparatus does not interact with the photons, but only with electrons and/or positrons.
So, how can a phenomenon-event occur relatively to O for half trip while not occurring for the second half trip and from S’s POV? The photons don’t “know” who are watching at them!
PS the experimental apparatus does not interact with the photons, but only with electrons and/or positrons.