Although I am a fan of scifi I feel that any discussion on time travel is missing a vital flaw, not that film producers have anything to complain about, but as science itself knows of the grandfather paradox then along with scientific knowledge and scientific confirmation that time does not exist then science fails to understand why it percieves time to go by , something that bothered einstein so he stated that the past present and the future are just an illusion , a good answer and ending to his inquisitive nature yet it still does not explain why we today still see time passing us by .