Now that the ship had phased, shifted again in time, he still had no real idea what their position was on the continuum. Was it still May of 1941, or had they moved to some other time? Did they shift forward, or slip deeper into the past? If the disappearance of these men was the result of Paradox, then he was inclined to think the ship might have moved forward again, to a point in time where they were now suffering the consequences of their many interventions. They had changed the course of events to a point where the life lines of Tasarov and the others were fatally compromised. This was all he could deduce at that moment.
The only thing he was relatively certain of was that Paradox was somehow involved. As the ship had sailed closer and closer to a moment in time where it already existed, these effects became more pronounced. The hand of fate was on them now, and he could see no way they could avoid it. His fear now was that the process was still underway, and other things could change—go missing, just like Kamenski and the others.
Yet just a moment, he thought. The ship doesn’t simply exist in time. It also occupies space, and the combination of its spatial position and its temporal position would define it as an event in spacetime… Then something struck him with thunderclap surprise. Two discrete objects could easily exist at the same time, but they could not exist in the same space. Therefore they could also not exist together in the same spacetime, which was a unified expression of both space and time.
Physicists and theoreticians were always trying to nail things down on a chart, just as he plotted the position of the ship for navigation. He was often asked to set an intercept course that depended on many variables, and this was always a chancy prediction. He could know an enemy ship’s last reported position, course, and speed, and then compare that with similar information on his own ship. This enabled him to set a course and speed that would potentially bring the two ships together in the same future moment of spacetime. And when this was happening with two opposing warships, battle would result, with one ship ruling the moment and prevailing, and the other either driven off or destroyed.
Just like two chess pieces trying to occupy the same space on a board, one or the other had to prevail. But we are not on an intercept course in spacetime, only in time. Our last reported position was just a few hundred nautical miles west of Lisbon, but that other ship, the one we arrived on, will appear in the Norwegian Sea. Two discrete objects can easily co-exist in the same time, but not the same spacetime. If this were so, then it suddenly occurred to him that it was not simply a collision in time that he should fear, but a collision in spacetime.
Was this the source of my confusion? I believed we were on an intercept course with that other ship, with our own selves as we appeared on July 28th of 1941. They are approaching that event in spacetime from the future, while we are approaching it from the past. I have been obsessed with the timing of the event, and I was ignoring the spatial element. We’ll reach July 28th, 1941 if we continue to move forward here, but that will be a separate event, from that defined by the other ship. We won’t be in the same spatial location, and therefore we won’t be in the same spacetime as the ship arriving from the future!
Now he remembered that terrifying moment when Kirov was in the Pacific. The ship had begun to pulse, its position in spacetime wavering and undefined. They had used Rod-25 to try and remove themselves from danger, then there came that strange event, where the cruiser Tone had appeared and seemed to plow right through the ship. He could still see it in his mind’s eye, and feel the terror of that experience. It was as if a ship of ghosts had sailed right through them on a collision course, spectral phantoms from another reality.
At that moment we were fortunately not in the same spacetime as the Tone. Otherwise the two ships would have had a fatal collision. He had been thinking about this all wrong, believing he had to be in a different temporal location when Kirov