If the 2045 initiative continues onwards as the founder intends, we're all going to be hearing more about what here is called "cybernetic immortality" - copying the data of the mind to run in machinery that is much more robust and longer-lasting than its biological equivalent. I consider the popularity of this goal (as put forward by Ray Kurzweil, for example) something of an existential threat, insofar as it may drain enthusiasm and allies from work on rejuvenation biotechnology now, and in future decades it may become cheaper to build mind-copies than to finalize the means to reverse and prevent aging in our biological bodies. You don't need to fully understand the brain to copy it given powerful enough computers and scanning tools, and you don't need to understand aging much better than we do today to create rejuvenation biotechnology.
There are more than enough people in the world who consider a copy of themselves a suitable continuation to support this sort of technology in preference over medicine for rejuvenation. Today a person can choose to support programs like SENS research on the rejuvenation side or the 2045 group on the mind copying side - it's not just talk, it's a rather important choice between aiming for continued survival of the self or aiming for death while a copy of you survives.
Cybernetic immortality - fantasy or scientific problem? I can answer that right away. It is a scientific problem - of approximately the same type as the problem of people going into outer space, which was proposed by Tsiolkovsky at the turn of the 20th century. Why, despite the support of important scientists (such as V. Turchin, C. Joslyn, R. Kurzweil, A. Bolonkin, B. Bainbridge and others), is this idea rejected by many, or at best treated with skepticism?
There are many reasons for this. Firstly: the scale of this super-project, which really does verge on fantasy, is too "overwhelming", for the "average" scientific mindset, which is mundane and cautious, and too dependent on the opinion of the scientific management. Anything is proposed nowadays if financing can be secured for it. I'm not even talking about the colossal growth of false science - charlatans, mages, "miracle-workers". All of this throws a shadow on the idea of cybernetic immortality.
Furthermore, we are now only at the approach stage of a solution to this problem, specific steps for its development are in many ways only at discussion level, and creative solutions are required. The eternal idea of immortality has been expressed in myths, legends and religious beliefs. Hence the prejudice that it is not compatible with science.
What is the basis for the conviction that the problem of cybernetic immortality is a real scientific problem? It does not contradict the principles of science. In fact, it finds a theoretical basis in them - above all, in the fundamental principle of the iso-functionalism of systems, which essentially heralded the beginning of the computer era. The idea of this principle is that the same complex of functions may be reproduced on substrates with different physical properties. Hence the fundamental possibility to reproduce the functions of a living system and the brain on non-biological substrates, which also fully applies to mental functions.