I can tell you right now that short of some metaphysical existence promised by religions that lies outside the plane of the mortal coil, it is not possible to live forever. I'm not saying we can't copy a conscience some day and through an overlay AI create something like eternal life. But even then, that can't last forever. Everything in the universe is finite, eventually energy will cease to exist to allow the AI to thrive. Hell, we can't even get a long term archiving process down, imagine an AI personality sitting in some dusty storage locker for thousands of years because 50 years after it was created, there weren't any terminals left to plug it jnto and allow it run, a la beta tapes.

We could transfer the AI between mediums, but then we are just making back up to the original, at what point do we say the original person who has been copied and transfered thousands of times over a million or so years is no longer the same person?

Also you need to clnsidder this, the AI would be replicated on a person who once lived for maybe 85 years, but the AI exists for thousands if not a million years, did the original person ever exist? Especially when the experiences and memories of the AI out number the progenitor 100:1, 1,000:1 or 10,000:1

Finnally who's going to keep the AI updated? The AI? Probably, it's funny, 100 million years from now, all that may remain of humanity would be the decendants of our AI overlays who for eons diligently copied and transfered the personalities of an extinct species from a planted that long since burnt to a crisp, and through that time those personalities too faded sending new AI overlays, shadows of themselves and hardly recognizable to the progenitors.

And like I said in the beginning, even if your AI decendants could make it to the end of the universe, eventually there won't be enough energy left to keep their circuits or whatever passes as information devices operational. Yes 10s of billions of years down the line in the darkness of space, of our decendants can even recall a time there were stars in the night skies, maybe somewhere in the recesses of their memory banks a floating sensation that can be remembered as warmth once felt by the progenitors will be their last conscious understanding as they too find their demise as everything else had done before and will do until the universe itself fades away.

So.... no its not possible to live forever