(Thanks to Steve O. for the loan of the collection Perchance to Dream)
"Father, Dear Father," Charles Beaumont
Time is the only thing that really interests Mr. Pollet and not so much what happened in the past or what will happen in the future but how alteration of time will affect him. He builds a time machine and after many attempts gets it to work and he travels back in time to the days before his conception. His father died when he was four and he is curious to see what would happen if he'd never been born. So he walks the streets of the town of his birth, finds the house he grew up in, and murders his father and nothing changes. Can you guess why?
This is a bit of a gimmick, but at its short length and nice writing, I think it worked reasonably well. It's all too familiar though to read about a guy whose only interest is in how time affects him. He could travel to any time and witness historic events but he is satisfied with only traveling to a small town in Ohio and murdering a man whose only sin (supposedly) lay in conceiving a son who is a narcissist and a murderer.
I will be tied up most of the day with various appointments so forgive me if I don't get to look at your choices until tomorrow.