This will be from memory.. read with a grain of salt.
I read a physicist that once explained this but said that his example wasn't exactly 'true', or rather, the full explanation. It was faulty BUT... it was a step one could use in getting "TO" an understanding of what was going on.
you're familiar with the law that you can never know where an electron is at any given time, and that the electron could be anywhere, and anywhere simultaneously. Same principle here. Since you can't 'know' where the photon is it can and could be "ANY" location - and any position in the universe is as 'possible' as any other.
Now if you can absorb that more power to you... because after typing that I need a shot of Grey Goose. - JamesJM
