Love is the net profit on life.

I like science fiction, I like fantasy, I like time travel, so I had this idea: What if you had a phone that could call into the past?

If time travel is possible, where are the tourists from the future?

Matter and energy are equivalent, according to the equation E=mc2, where E stand for energy, m for mass and c for the speed of light,' 'Merapa explained. 'Matter can't be transported at the speed of light but energy can. Therefore, during a time shift transformation, matter is converted to energy then condenses back. In other words all the molecules in your body have been changed from matter to energy then back again.'
'Wow. It's a wonder it's not fatal,' Dirck said.
'Sometimes it is. If any transcription errors occur between the DNA and RNA in your vital organs you're all but dead.

Perhaps you would have preferred it if I had not written you any letter. Perhaps you would have liked it better if I had let you meet your fate unprepared. After all, what awaits you is not all that bad and even contains moments of happiness, as you have seen. But if I wrote to you, it is because somehow I feel this is not the life you should live. Indeed, perhaps you should stay in the past, living happily with Jane and turning me into a successful writer who knows nothing about journeys through time, not real ones anyway. For me it is too late, of course, I cannot choose a different life, but you can. You can still choose between your life and the life I have just recounted to you, between going on being Bertie or becoming me. In the end, that is what time travel gives us, a second chance, the opportunity to go back and do things differently.

Science fiction is filled with Martians and space travel to other planets, and things like that.