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Life is a braid in spacetime

nautil.us

41–42 of 42 posts

Re: Life is a braid in spacetime

#41
post #10
post #5

Earlier quoted context omitted.

Actually there are parts of you that were parts of you in your twenties. Some of the brain cells, some of your heart cells, and if you are a woman, your eggs. Unless you are talking about how matter pops in and out of a apparent reality, in which case we're going too far down for me.

The cells persist, but the atoms that make up those cells are still replaced over time.

Source?

Re: Life is a braid in spacetime

#42
post #30
post #11

The idea of "spacetime" makes a fun narrative, fun thought experiments, and interesting ways to graph and visualize events. But many physicists wish that popularizing this concept would stop and go away, because it is misleading. There is both evidence and theoretical work demonstrating that time, unlike the spatial dimensions, is not a choice when it comes to direction of travel, and never will be. The definition of…

dahart: >> has been mistranslated in popular science culture as a thing that somehow opens up the option of time travel. Ah, time travel isn't science fiction. Clearly we have concrete experiments that show this is common place, easy and done all the time. The faster you go in the space dimension, the slow you move in the time dimension. Now certainly being able to go back in time is something of speculation, and mor…

You're right, and that's my understanding too. But I would say that relativistic perception of time does not classify as "time travel", unless mere existence classifies as time travel. Yes, time slows down or speeds up depending on velocity, but not in a way that you have any control over. Time is not a choice, its not an axis upon which you can choose your direction of travel, it is only something you are subjected to and can observe.

Now, I guess this is a very subjective discussion, but saying you can "jump into other people's future" feels like a way to make it sound sexy while glossing over the boring detail that you have to sit through all the intervening time along the way, the "jump" isn't instantaneous, and once you "jump", there's no going back. In this sense, we're always jumping into the future each and every second, and it would be equally correct to state as fact that we can wait into other people's future.

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