A while back, a reader of my blog asked me to respond to the following video in which Sean Carroll discusses why he doesn't believe in the afterlife:
[Please note that, as a matter of policy I will not review or respond to ideas that are encapsulated in videos, unless there is a text transcript. I made an exception for this particular person, as a very special favor which is not to be repeated...]
I replied more or less as follows:
I'm familiar with Sean Carroll's arguments and while I understand that they may be intimidating, he's leaving out something pretty important here. Namely God.
Of course Carroll is an atheist and so he doesn't believe in God. But we Christians do think there is evidence for God and miracles from e.g. the Resurrection of Jesus. Even Carroll admits that sufficiently powerful evidence could change the conclusion that QFT is a complete description of nature. He just hasn't yet understood that that this evidence does in fact exist, in the form of the historical documentary evidence for miracles. This of course requires us to believe that, contrary to what Carroll said, sometimes things outside of our current understanding of physics do affect the human world. But that's not as implausible as he makes out, since it often happens in Science that a theory is very accurate in certain circumstances, except in rare situations where it completely fails due to interaction with new kinds of things. If the new thing was just new kinds of QFT particles, then it couldn't really work (for all the reasons Carroll mentioned), but if it is something like God, that would not fall under the purview of QFT!
Now while Carroll has defended his Atheism elsewhere, this particular debate was about life after death, not Atheism. For the purposes of this debate, he's basically just assuming that Materialism is true, and that therefore the only way there could be life after death is if the information in our brain was preserved by some physical mechanism.
Now I actually agree with him that it is very implausible, if Materialism is true, for there to be any physical mechanism which preserves our mind after death! So nothing he said bothers me. Because I don't think that the reason we will live forever is because we have some magical soul-particles in our brain (not yet discovered in the laboratory) which happen to have the property of being immortal.
Instead I think the reason we will live forever is that God loves us and that he's promised to do it. So at the end of time, when Jesus comes back, God will raise us from the dead in new physical bodies, and if that violates the current laws of physics that's okay by him. (If he wants to copy our information into some other format to keep us self-aware in between the time of our death and Resurrection, he can do that too! The New Testament suggests that probably something like this is the case, but it puts a lot more emphasis on the Resurrection of our bodies when Jesus returns.)
I also think that Carroll is more confident than he should be that the Laws of Physics can explain why physical systems are conscious. The so called "Hard Problem of Consciousness" is an extremely deep philosophical puzzle, and even many atheistic philosophers (like David Chalmers or Thomas Nagel) think that there is a mystery here which is very hard to explain on a purely reductionistic materialistic worldview. While this is a very interesting topic (which suggests that, at some level, Materialism is wrong about some deeply important things), I think it is hard to really prove for sure that this would imply anything about life after death. Traditionally, many theistic philosophers have tried to prove the Immortality of the Soul through philosophical reasoning, based on facts about the supposed immateriality of the mind, but the Philosophy of Mind is sufficiently confusing I don't think this is the best way forward.
I would instead focus on the fact that God has promised, in the Bible, to raise human beings from the dead and made an advance demonstration of this with Jesus. Our confidence that he keeps his promises (a.k.a. "faith") is based primarily on our relationship with him and not based on the kinds of pro and con arguments which were made in this debate. I think our confidence that we will live forever is going to be proportional to our love and knowledge of God, so if you find yourself having difficulty believing in Heaven, the solution is not to directly try to believe in that harder (in isolation from other things) but rather to meditate further on your relationship with Jesus, and then the afterlife issue will straighten itself out automatically. That's not to say that what we believe about the afterlife isn't important, but only that it follows from a correct understanding of who God is.