There are times when, while doing mundane chores – like changing the bed linen and making the bed – that the mind wanders to silly things. In my case, it wandered to the concept of TIME TRAVEL.
How nice to go back an kill Hitler before he became the corporal who wrote Mien Kampf. Just think of all the lives that would have been saved.
Or should I say – created, never created, never born, or born though they never were. There would have been no mobilization – and the Japanese expansion – the possibility of a Pearl Harbor - would have played out in a considerably different manner. Without Hitler, the Depression would not have had the war related military expenditures to bring it to an end.
Without Hitler, the baby-boom would not have occurred – couples who delayed marriage or children because of the war would have married and had a few children … the timing of the ones they had would have shifted; none of us, or our parents, would have come into existence. This is especially true for children associated with troops and the movements of men due to military assignment.
There would have been no European refugees – especially the Jewish refugees who made the nuclear age possible. No German Jews in America or Russia – probably not Cold War. The Socialist movement in America would not have been brought to an end, and we might well have gone into a phase where we were Communist rather than Capitalist.
The real point here? Those who traveled in time would not have existed – so could not have traveled in time to change things. Or they would end their reality, and create a new one … one in which they magically appear, do their thing, probably get captured, arrested, and tried for murder … maybe tell their story, and get locked away in some nut house … but the world they knew, the world which created them, would not exist – it would have ceased to exist the moment they did anything that altered history.
On the other hand. Time could be sped up … one could go into the future and see what it was like. To change a future event, or alter an event that will happen tomorrow, would only alter the future and have no real effect on today. One could bet on the outcome of an event which is already happening – place an order at the opening of the stock market, or one a ball game which is in progress, or even on the turn of a card that is about to be dealt. The effect of winning where a win was not before? It would only change the lives of those who have yet to live the events which have been altered. You change a future which has not yet occurred and so shift history… in the example of Hitler, it is the Hitler who will emerge thirty of fifty years AFTER the time machine is made operational – it is his world, and his effect on it, which will be altered. Those alive today will simply have a different world to deal with … one that has not yet to come into existence and so has no effect on them today.
A time machine could alter events tomorrow, and so shape events the day after – with nobody the wiser. (except the time travelers themselves) An H. G. WELLS could look into the future and describe it. One could alter the future by writing a “1984” in which the visualized world is described, and so the people are warned, and small alterations in their behavior prevent it from happening.
But you cannot go back in time … at least not more than a few minutes, maybe a few hours, or, at most a few days. Any significant travel into the past would bring about the end of the present from which the traveler began their journey.
But .. We already know that.