5 ms·

im a big fan of the idea that anyone who uses FTL with the intent of sending messages back in time has it not work

doliveira 5y ago
Fermi paradox: advanced civilizations discover time travel and generate paradoxes that erase the timelines that led to their creation
- GolfPopper 5y ago
  This is explicitly the background for SF author C.J. Cherry's Morgaine Cycle, although the destruction isn't complete and leaves fragments scattered across space and time. (The reaction of a interstellar human civilization to discovering the fragmented network of space-time gates is "shut it all down and bury it".)
  - EarthLaunch 5y ago
    That sounds fascinating, I'll read that. C.J. Cherryh is one of the authors I somehow didn't pick up as a child, even though I was reading C.S. Friedman and the like. Maybe it was the covers.
  - doliveira 5y ago
    Wow, here's to me thinking I had had an original idea... But that book sounds fascinating, I'll be sure to check it out
    - BizarroLand 5y ago
      I think it was Stephen Baxter who said that if we live in a universe where time travel is possible, then we live in a universe where time travel is not possible, as if it will have happened then everything that can will have happened has already happened.
mrfusion 5y ago
I think you’re describing this? https://en.m.wikipedia.org/wiki/Novikov_self-consistency_principle https://en.m.wikipedia.org/wiki/Novikov_self-consistency_pri...
- AnIdiotOnTheNet 5y ago
  I've actually thought a lot about this, in particular because I had a dream involving Novikov self-consistency principle. I think the base idea behind self-consistency principle is that it prevents grandfather paradoxes but allows bootstrap paradoxes. In other words, stable time loops are allowed but unstable ones aren't. I submit that it is possible to have meta-stable time loops such that all grandfather paradoxes are ultimately meta-bootstrap paradoxes. Assume that if time travel is possible, then changing the course of events must be also be possible just as directing future events by our decisions in the present is. If one goes back in time and kills their own grandfather, they have altered the future such that they are never born in order to time travel in the first place, a grandfather paradox. However, since time travel must have existed in order for this situation to occur, then undoubtedly someone else at some future date within this timeline will seek to change history as well. To keep this scenario simple, imagine that this person travels back in order to kill you before you are able to kill your own grandfather, thus restoring your original timeline in which you travel back to kill your own grandfather. This is a meta-stable time loop employing a meta-bootstrap paradox. Each timeline exists and is dependant on time travel from the other. Arbitrarily complex structures are possible involving arbitrarily many timelines, which in an infinite meta-time universe suggests the possibility that all time travel must resolve in this way. I came up with this years ago, but have only ever seen something like it explored once: in the TV show 'Dark'.
  - mrfusion 5y ago
    That’s a great way to think about it. It reminds me of the Temporal integrity division in the 29th century in Star Trek.
  - godot 5y ago
    > I came up with this years ago, but have only ever seen something like it explored once: in the TV show 'Dark'. Doraemon, a Japanese children's cartoon (1970s to 1990s), created by Fujiko F Fujio, who is actually very well-versed in physics and science, has used something like this as a plot point in several different chapters/episodes and some movies. It doesn't actively call them "meta-stable time loops", since its target audience is children, but the idea and concept is there. Growing up watching and reading this series, I've learned more and more from it as I rewatch/reread old chapters/episodes, every time. I absolutely love it.
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Jenk 5y ago
Doesn't FTL make time slow for the travelling party? Or does it flip when you velocity is greater than C?
- roywiggins 5y ago
  You'd end up returning to your own past if you took a round trip to Alpha Centauri faster than light, so more or less, yeah.

Fermi paradox: advanced civilizations discover time travel and generate paradoxes that erase the timelines that led to their creation

GolfPopper 5y ago
This is explicitly the background for SF author C.J. Cherry's Morgaine Cycle, although the destruction isn't complete and leaves fragments scattered across space and time. (The reaction of a interstellar human civilization to discovering the fragmented network of space-time gates is "shut it all down and bury it".)
- EarthLaunch 5y ago
  That sounds fascinating, I'll read that. C.J. Cherryh is one of the authors I somehow didn't pick up as a child, even though I was reading C.S. Friedman and the like. Maybe it was the covers.
- doliveira 5y ago
  Wow, here's to me thinking I had had an original idea... But that book sounds fascinating, I'll be sure to check it out
  - BizarroLand 5y ago
    I think it was Stephen Baxter who said that if we live in a universe where time travel is possible, then we live in a universe where time travel is not possible, as if it will have happened then everything that can will have happened has already happened.

mrfusion 5y ago

I think you’re describing this? https://en.m.wikipedia.org/wiki/Novikov_self-consistency_principle https://en.m.wikipedia.org/wiki/Novikov_self-consistency_pri...

AnIdiotOnTheNet 5y ago
I've actually thought a lot about this, in particular because I had a dream involving Novikov self-consistency principle. I think the base idea behind self-consistency principle is that it prevents grandfather paradoxes but allows bootstrap paradoxes. In other words, stable time loops are allowed but unstable ones aren't. I submit that it is possible to have meta-stable time loops such that all grandfather paradoxes are ultimately meta-bootstrap paradoxes. Assume that if time travel is possible, then changing the course of events must be also be possible just as directing future events by our decisions in the present is. If one goes back in time and kills their own grandfather, they have altered the future such that they are never born in order to time travel in the first place, a grandfather paradox. However, since time travel must have existed in order for this situation to occur, then undoubtedly someone else at some future date within this timeline will seek to change history as well. To keep this scenario simple, imagine that this person travels back in order to kill you before you are able to kill your own grandfather, thus restoring your original timeline in which you travel back to kill your own grandfather. This is a meta-stable time loop employing a meta-bootstrap paradox. Each timeline exists and is dependant on time travel from the other. Arbitrarily complex structures are possible involving arbitrarily many timelines, which in an infinite meta-time universe suggests the possibility that all time travel must resolve in this way. I came up with this years ago, but have only ever seen something like it explored once: in the TV show 'Dark'.
- mrfusion 5y ago
  That’s a great way to think about it. It reminds me of the Temporal integrity division in the 29th century in Star Trek.
- godot 5y ago
  > I came up with this years ago, but have only ever seen something like it explored once: in the TV show 'Dark'. Doraemon, a Japanese children's cartoon (1970s to 1990s), created by Fujiko F Fujio, who is actually very well-versed in physics and science, has used something like this as a plot point in several different chapters/episodes and some movies. It doesn't actively call them "meta-stable time loops", since its target audience is children, but the idea and concept is there. Growing up watching and reading this series, I've learned more and more from it as I rewatch/reread old chapters/episodes, every time. I absolutely love it.

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Jenk 5y ago

Doesn't FTL make time slow for the travelling party? Or does it flip when you velocity is greater than C?

roywiggins 5y ago
You'd end up returning to your own past if you took a round trip to Alpha Centauri faster than light, so more or less, yeah.