Think of it this way
When people dream their dreams may only be 24 hours but they feel longer(or shorter)
this is why people in comas may think they only were out for a night
Death is like eternal sleep so if a person falls asleep before death their conciseness may last to them even after they die
why?
Because time in dreams is relative
think of it this way
bob has a dream for one second in our time before he dies
in bobs time though it lasts forever
[spoiler]and also with quantum physics anything is possible tbh[/spoiler]
Also found this http://www.learning-mind.com/quantum-theory-proves-that-consciousness-moves-to-another-universe-after-death/
Edit2.0 No one likes my pun in the tag? LightningPhilosiphynix? anyone? *grabs Knife* Yall better start laughing real soon or your consciousness will be in another universe