: I should also mention that I'm about 7 years behind in any physics
: reading.
Let's not forget that the original Marathon was released 7 years ago, so your physics is not all that far behind Bungie's in the Marathon universe. I've tried to keep up with recent developments in physics, but the amount of new information in astrophysics is overwhelming for those not primarily in that field of science. The issue of the closure of the universe has been a very hot topic of debate for decades. Einstein proposed 3 possibilities - a closed (spherical) universe, a flat universe and a "saddle" shaped universe (in 5-D space-time). Although most scientists I think feel most comfortable with the idea of a closed universe (we all like closure), all evidence to date has suggested a flat universe that will expand indefinitely, with all matter eventually decaying into nothingness. This is an interesting point, for even if we presumed a closed universe, Durnadal would not only have to figure out how to prevent closure, but he would need to find a way to prevent particle decay - otherwise there would be nothing left to comprise his circuits. There is also the much more urgent matter of information decay - random mutations in his database will ultimately lead to his senility, no matter how much redundancy he might build into his construct.
One of the reasons that I think most of us like the idea of a closed universe is that we find it hard to accept a finite beginning without a finite end. The philosophical argument is that we must return to a quantum singularity in order for the universe to be recycled - i.e. to be reborn as a new universe. This of course is rather egocentric view, as it presumes that the universe we know is the sole reality. Our universe apparently came out of nothingness and it can decay into nothingness just as easily as it can collapse into nothingness. Many have suggested the idea of multiple spatial demensions beyond our own space-time and the possibility of other universes that are perpendicular and thus invisible to our own. But this is also an egocentric view. Our own space-time was born at the instant of the Big Bang and if there are other universes in other dimensions, they would have also have needed to originate at the time of our own Big Bang. This is possible, but I think unlikely, as the reason I believe that there are 3 spatial dimensions is that this is the simplest and, hence, most probable form consistent with atomic structure. 1 and 2-D universes may well be even more likely, but they could not result in the formation of matter as we know it. This is all going out on a limb and I have nothing to back it up, but to me this is the most intuitive explanation of why we are what we are, not that modern physics is in any way intuitive. Are there other universes? I think that there almost certainly are, some of which may have formed by a process of budding from our own. The possibilities are well beyond human comprehension and just slightly off-topic for this forum. Hence Durandal's concerns about the closure of the universe can stand as they are within the realm of our imagination.
