How do you have four doctors in the same place at the same time?
It has something to do with Temporal Fission. At the end of the Five Doctors, Docs 1, 2, and 3 enter the TARDIS and each one flies off individually. The Death Zone on Gallifrey was created by the primordial Time Lords for amusement and entertainment, and thus one can surmise that it exists out of space, out of time. One could also propose that it is an ablilty inherent in the timescoop - being able to lift anyone from any time, thus enabling the doctor in different stages of his life to exist at the same time.
And let us not forget we have seen it happen already in this series...Rose went back to a time when she was a baby in "Father's Day".
How do you have four doctors in the same place at the same time?
It has something to do with Temporal Fission. At the end of the Five Doctors, Docs 1, 2, and 3 enter the TARDIS and each one flies off individually. The Death Zone on Gallifrey was created by the primordial Time Lords for amusement and entertainment, and thus one can surmise that it exists out of space, out of time. One could also propose that it is an ablilty inherent in the timescoop - being able to lift anyone from any time, thus enabling the doctor in different stages of his life to exist at the same time.
So in fact, if what the Sun says is true, the new doctor (ie. David Tennant) could in fact be a previous encarnation of the doctor from centuries ago? Interesting...