Not exactly an “afterlife” per se. But stay with me on this.
Space is most likely infinite in extent. The amount of information in the part we can see (our “Hubble Volume” – the part of space where light has had a chance to reach us) is finite. Given an infinite number of trials, every possible outcome will happen an infinite number of times. (Given infinite D20 rolls, you’ll get an infinite number of natural 20s. Not only that, but an infinite number of 1,000,000-roll natrual 20 streaks.) So, there’s a good case to be made that there’s an infinite number of exact of copies of our Hubble Volume out there.
But also, something interesting about Quantum Mechcanics is that it predicts that the goings on in spacetime (hand wave, qualifier) aren’t deterministic. Sometimes the exact same same initial conditions and the exact same laws of physics can have different outcomes. So if you could check the state of two Hubble Volumes that are exactly identical now, there’s a likelihood that after some time has passed, the two will no longer be identical.
So how likely is it that you’ll live to be 100? Probably a little under 1%. What about 110? I don’t know off the top of my head, but let’s say it’s around 0.1%. 120? Maybe 0.01%. (Yes I’m making these numbers up, but what the numbers actually are doesn’t matter that much for this thought experiment.) How likely is it that you’ll live to be 200? Pretty unlikely, but it’s definitely not zero.
Given infinite exact copies of you and a non-zero chance that each one will live to be 200, you can expect an infinite number of copies of you to live to be 200. And why stop there? 300? Still an infinite number. 400? Still infinite. Is there any ceiling? Only if there’s an age at which there is a truly 100% chance that you won’t survive to. So, maybe the heat death of the universe, then? Asserting that the chance of living that long is zero assumes we won’t find a “loophole” in the Second Law of Thermodynamics. (In fact, the Second Law of Thermodynamics is a statistical law, not an absolute one. It’s not true that entropy always increases in a system. Only that it does the incalculably vast majority of the time. There’s always technically a chance that all the air molecules in the room you’re in will happen to meander to one half of the room, which would be an example of entropy spontaneously decreasing. It’s only a technicality, but we don’t need more than a technicality for this thought experiment.)
All that to say, there’s a case to be made that there’s a possibility that at least one version of your consciousness will “live” forever.
I say “there’s a case to be made” because indeed what I’ve said above depends on a few assumptions. (For instance, it is possible that for any one particular person, there might be some unknown reason why there’s a truly 100% chance that they’ll die before a certain age.)
This whole train of thought is related to the concept of “Quantum Immortality.” And if it intrigues you, I highly recommend Max Tegmark’s book “Our Mathematical Universe.”
And again, it’s not an “afterlife” per se. But might go at least a little bit in the direction of the question you’re asking.