I am not sure how many of these ideas are new. I came to write a synthesis of them while writing a large novel. Two ideas are key: the first is that a person can exist in a virtual reality world hosted on a supercomputer. The second is that such a person does not have to be just a copy of its realworld predecessor, but can actually be that person. Creating a copy of yourself in a computer is not true immortality, because that person is only a copy, no matter how good a copy. But I claim that the person himself or herself can be transfered into the virtual reality world.
There are two metaphors which illustrate this point. One is the notion of putting two computers in parallel, having them work in parallel for a while, then shutting one down. Suppose a large neural network hosted on a supercomputer as a model for a person is synched to a person, using as much of the person’s own inputs and outputs as possible to maintain synchronization. Then a biological computer and an electronic one are working in parallel. At that point the biological computer can be shut down, leaving the syncronized electronic one to continue. That can be seen as a transfer of a person into the virtual reality world maintained on the electronic supercomputer. This may be at least a metaphor, possibly a practical method for achieving true immortality.
Another metaphor is related, but simpler and perhaps easier to understand. Imagine a two necked 12-string guitar, with each neck having the same pitch range. Let a chord be started on one neck, one set of strings, and sustained with the feedback based sustain lever. Now finger the same chord on the other neck, other set of strings, perhaps with the aid of another person. Even without anyone playing (striking) the second set of string, they will start to vibrate through sympathetic vibration. Then both sets of strings will be synchronously playing the same chord. Now if the first set of strings is completely damped to soundlessness, probably with the aid of another person wielding a felt damper, the original sound, unchanged in any way, will continue on the second set of strings. Think of this as a transfer of personality and identity from one medium to another.
Through consideration of both metaphors and especially the first, which may be a practical method, I have come to the conclusion that real immortality in a virtual world is possible. Computers powerful enough to host such a virtual reality world and some number of inhabitants probably already exist and will certainly be widespread in the future.
I have another way of thinking about this, based on wave mechanics and integral transforms, but that is a bit much for now. I’ll post it on request.
I hope anyone who reads this will also look at the Finding Compatibles blog on this site. It may seem to be on an entirely different topic, but I claim that to accomplish anything, even making immortality practical for everyone, one must start by finding people who can work together.