5 ms·

Didn't read the article, but it's always fun following these lines of thought. We have no evidence of life outside earth, but darn it...we can't be the only one

Didn't read the article, but it's always fun following these lines of thought. We have no evidence of life outside earth, but darn it...we can't be the only ones here...I mean we can, but that just doesn't sit well with me. I wonder if almost any civilization would end up using lightsails powered by beams or if many skip it in favor of some other technology.

adrianN 10y ago
I like to think that black hole propulsion is the way to go https://arxiv.org/abs/0908.1803 https://arxiv.org/abs/0908.1803
- saalweachter 10y ago
  Fusion candles. https://www.schlockmercenary.com/2003-08-03 https://www.schlockmercenary.com/2003-08-03
felipemnoa 10y ago
It will probably be something similar to this [1] that allows humans/aliens to travel to distant worlds. As per my limited understanding, nothing can move faster than light in space-time, but it seems that it may be possible for a space-time wave to move faster than light. We would just ride that wave. [1] https://en.wikipedia.org/wiki/Alcubierre_drive https://en.wikipedia.org/wiki/Alcubierre_drive
- AnkhMorporkian 10y ago
  That requires the existence of exotic matter, something that really isn't known to exist at all, and it'd be pretty surprising if it did. Pretty much all FTL schemes require some exotic thing that's unlikely to actually be feasible in our universe.
  - felipemnoa 10y ago
    The bending of space is possible though. We could figure out how to bend space in a different way. Think about it, alchemists were trying to figure out how to turn lead into gold. We now know how to transmute an element into gold, although not economically. Science is till pretty young. I wouldn't rule out something similar to the Alcubierre Drive for space travel.
- M_Grey 10y ago
  Remember that any such device allows you to travel backwards in time. Does it still seem so plausible to you when you realize that 'c' isn't some kind of cosmic speed limit, but the speed of causality in the universe?
  - pavel_lishin 10y ago
    Other than the fact that it seems mind-boggling, is there any reason to believe that time travel is forbidden by the laws of physics, or that causality is an absolute?
    - M_Grey 10y ago
      You've heard of the progress of entropy and the "thermodynamic arrow of time" right? Time travel into the past, violating causality... it breaks the math used to formulate the most basic physics at a very fundamental level.
      - pavel_lishin 10y ago
        Does that mean that it's impossible, or that our current model of physics simply doesn't account for causality violations? We got along okay with Newton until Einstein came along and upgraded the model.
        M_Grey 10y ago
        Definitely the latter, there's no way to say it's impossible, just incredibly unlikely. It's easy to imagine a universe in which it is possible, and that universe could be consistent with the math. The big "but" however is that our universe has none of the features we'd expect from one with the necessary curvature or exotic matter/energy. Does that make sense? I mean, if we discover that there are multiple universes, or that Block Universe is true.... who knows? Even then however, I suspect we'd run into something like Novikov Self-Consistency Principle, or we'd have noticed time travel by now.
    - openasocket 10y ago
okket 10y ago
Still unlikely, see the Fermi Paradox and The Great Filter http://waitbutwhy.com/2014/05/fermi-paradox.html http://waitbutwhy.com/2014/05/fermi-paradox.html
- throwaway7645 10y ago
  Favorite of mine. The author did a tremendous job.
openasocket 10y ago
I've always wondered if we're already observing evidence of extraterrestrial civilizations, we just think it's some natural phenomenon. All of astronomy is based on observation, if we mistake alien activity for a natural process it could completely screw up our understanding of what's going on. For instance, maybe Quasars are artificial super-structures, created as a power source, or a beacon to signal other civilizations (similar to the signals SETI broadcast) or something else. NOTE: I don't know nearly enough about astronomy to speculate which phenomena could be potentially artificial, but I do think it is a distinct possibility.

adrianN 10y ago

I like to think that black hole propulsion is the way to go https://arxiv.org/abs/0908.1803 https://arxiv.org/abs/0908.1803

saalweachter 10y ago
Fusion candles. https://www.schlockmercenary.com/2003-08-03 https://www.schlockmercenary.com/2003-08-03

felipemnoa 10y ago

It will probably be something similar to this [1] that allows humans/aliens to travel to distant worlds. As per my limited understanding, nothing can move faster than light in space-time, but it seems that it may be possible for a space-time wave to move faster than light. We would just ride that wave. [1] https://en.wikipedia.org/wiki/Alcubierre_drive https://en.wikipedia.org/wiki/Alcubierre_drive

AnkhMorporkian 10y ago
That requires the existence of exotic matter, something that really isn't known to exist at all, and it'd be pretty surprising if it did. Pretty much all FTL schemes require some exotic thing that's unlikely to actually be feasible in our universe.
- felipemnoa 10y ago
  The bending of space is possible though. We could figure out how to bend space in a different way. Think about it, alchemists were trying to figure out how to turn lead into gold. We now know how to transmute an element into gold, although not economically. Science is till pretty young. I wouldn't rule out something similar to the Alcubierre Drive for space travel.
M_Grey 10y ago
Remember that any such device allows you to travel backwards in time. Does it still seem so plausible to you when you realize that 'c' isn't some kind of cosmic speed limit, but the speed of causality in the universe?
- pavel_lishin 10y ago
  Other than the fact that it seems mind-boggling, is there any reason to believe that time travel is forbidden by the laws of physics, or that causality is an absolute?
  - M_Grey 10y ago
    You've heard of the progress of entropy and the "thermodynamic arrow of time" right? Time travel into the past, violating causality... it breaks the math used to formulate the most basic physics at a very fundamental level.
    - pavel_lishin 10y ago
      Does that mean that it's impossible, or that our current model of physics simply doesn't account for causality violations? We got along okay with Newton until Einstein came along and upgraded the model.
      - M_Grey 10y ago
        Definitely the latter, there's no way to say it's impossible, just incredibly unlikely. It's easy to imagine a universe in which it is possible, and that universe could be consistent with the math. The big "but" however is that our universe has none of the features we'd expect from one with the necessary curvature or exotic matter/energy. Does that make sense? I mean, if we discover that there are multiple universes, or that Block Universe is true.... who knows? Even then however, I suspect we'd run into something like Novikov Self-Consistency Principle, or we'd have noticed time travel by now.
  - openasocket 10y ago

okket 10y ago

Still unlikely, see the Fermi Paradox and The Great Filter http://waitbutwhy.com/2014/05/fermi-paradox.html http://waitbutwhy.com/2014/05/fermi-paradox.html

throwaway7645 10y ago
Favorite of mine. The author did a tremendous job.

openasocket 10y ago

I've always wondered if we're already observing evidence of extraterrestrial civilizations, we just think it's some natural phenomenon. All of astronomy is based on observation, if we mistake alien activity for a natural process it could completely screw up our understanding of what's going on. For instance, maybe Quasars are artificial super-structures, created as a power source, or a beacon to signal other civilizations (similar to the signals SETI broadcast) or something else. NOTE: I don't know nearly enough about astronomy to speculate which phenomena could be potentially artificial, but I do think it is a distinct possibility.