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I don't get why no one ever throws out time travel as an explanation over extraterrestrial. Given the limit of the speed of information and the expansion of th

by kromem 3y ago

I don't get why no one ever throws out time travel as an explanation over extraterrestrial. Given the limit of the speed of information and the expansion of the universe, there's a VERY small area that would even be aware of the signals we've started sending out over the past century to come looking. But Earth would be an extremely interesting destination....for future Earth. Though personally the most likely answer is that it's our own tech that the people sighting it don't have clearance to even know about which is why USINT is so against more attention to reports of sightings. But if I had to put my money on outlandish claims, time traveling ships would get my best any day over extraterrestrial ones.

jareklupinski 3y ago
yea, given the progress we've made in harnessing physics over the past few hundred years, extrapolating for the lifetime of our species, as long as we're around for long enough to figure out time travel... we should be able to come back, which means we would already be doing so? as long as the preconditions remain true... either way we would probably have some sort of "butterfly effect/grandfather paradox" laws in place that said, the value of future earth visiting past earth would likely be 'kitsch' at best :P
DropInIn 3y ago
If you travel "back in time" you don't enter your own timeline but another universe where you were Always going to appear. Time travel (backwards) is not possible, only inter-universe travel. What has happened has always happened and will always have happened.
- MrYellowP 3y ago
  Finally I found an expert in time travel technology! Please tell us more about it!
  - DropInIn 3y ago
    Jfc... I see your hyperbole but I'll give you the "self evident" breakdown of why: If both events have occurred at the same time then that means they can't exist in the same timeliness. Pretty freaking simple ain't it?
krapp 3y ago
That aliens (specifically the "greys") are future versions of humanity who have traveled back in time for some reason (usually specified to be the recovery of "native" genetic material to re-engineer their ecosystem) is a well-worn narrative within UFO mythology. No one on HN "throws it out" because this is ostensibly a rational community and time travel is an even more absurd, less scientifically plausible solution than FTL or interdimensional travel. At that point we're just discussing comic book plots. If you believe we live in a universe that runs by comic book rules that's fine - it seems a depressing number of people here do, but there isn't much viable, intellectually grounded discussion to be had about that. You either agree with it or you don't. I mean hell, let's throw Jacques Valee onto the pile and say maybe UFOs/aliens are fae taking on a modern form in order to feed upon humanity's collective fear of the other. Makes about as much sense as time travel.
constantcrying 3y ago
Time travel backwards is causality breaking, which is a far, far more important physical principle than relativity. Time travel forwards is quite simple though, but less exciting.
- jpadkins 3y ago
  we can't rule out time travel forward on Earth. There is geological evidence of civilization destroying events 12k years ago, possibly more. I've often thought about why it took 300-400k years to go from fire to agricultural-civilization, then tech takes off in under 5k years from that point. What if the time from fire to civilization was faster, but those civilizations were wiped out (by geological, astrological or self-inflicted reasons)?
  - phyrex 3y ago
    There’s good evidence against that. All the easily mineable resources that a civilization needs to build more advanced technology will be used up by the first civilization. I’ve heard it said that if we destroy our current technology there will be no way to rebuild it because there’s no way to mine the resources to build it back up.
    - ryandvm 3y ago
      Today's landfills are tomorrow's mines.
    - jpadkins 3y ago
      Yes, I've read that without easily accessible surface level coal, there is no industrial revolution. Maybe the advanced past civilizations were based in what is now called Africa or Indonesia, and the UK was some remote frozen place where it wasn't worth it to mine the surface coal?
  - Shawnj2 3y ago
    From what I’ve heard it’s completely plausible for pre industrial human civilizations to have existed and been wiped out in the past but anything past that point would leave things like heavy metals we could detect in the geological record.
rdtsc 3y ago
Since the earth, and the whole solar system, along with the galaxy are moving through space, I can imagine some clever scientist discovering time travel, firing up they time machine, only to then find themselves in vacuum of space in a place the earth had long passed by already. Others try to calculate and predict the position. But they didn’t use enough floating point precision bits and ended up in the earth’s crust or somewhere in the ocean.
- StrictDabbler 3y ago
  There's an Isaac Asimov story from the 50's that I wonder if you've read. It's called "Blank!" In the story the scientist takes a friend forward 22 hours, but outside the time machine door there's nothing. Total darkness. The friend asks if the scientist forgot the movement of the Earth and the galaxy, but the scientist assures him that no, that motion has been accounted for. Instead it appears they've arrived between quantum periods, stuck forever out of phase with ordinary time like an elevator stuck between floors and frozen by the lack of momentum. I ask because that's the first story I read that drew attention to needing to travel in space to keep up with the planet.
  - rdtsc 3y ago
    Thanks for the suggestion, I was not aware of "Blank!". What inspired me to write the comment is was thinking about time travel and how people in movies and stories seems to always materialize on a nice level surface, somewhere in a building with the their feet exactly on the floor, in a nice meadow outside the city, on a sidewalk etc. Then, remembering how earth and galaxy move through space I thought how extremely hard would be to get a safe set of future spacetime coordinates to land on.

by kromem 3y ago

jareklupinski 3y ago

yea, given the progress we've made in harnessing physics over the past few hundred years, extrapolating for the lifetime of our species, as long as we're around for long enough to figure out time travel... we should be able to come back, which means we would already be doing so? as long as the preconditions remain true... either way we would probably have some sort of "butterfly effect/grandfather paradox" laws in place that said, the value of future earth visiting past earth would likely be 'kitsch' at best :P

DropInIn 3y ago

If you travel "back in time" you don't enter your own timeline but another universe where you were Always going to appear. Time travel (backwards) is not possible, only inter-universe travel. What has happened has always happened and will always have happened.

MrYellowP 3y ago
Finally I found an expert in time travel technology! Please tell us more about it!
- DropInIn 3y ago
  Jfc... I see your hyperbole but I'll give you the "self evident" breakdown of why: If both events have occurred at the same time then that means they can't exist in the same timeliness. Pretty freaking simple ain't it?

krapp 3y ago

That aliens (specifically the "greys") are future versions of humanity who have traveled back in time for some reason (usually specified to be the recovery of "native" genetic material to re-engineer their ecosystem) is a well-worn narrative within UFO mythology. No one on HN "throws it out" because this is ostensibly a rational community and time travel is an even more absurd, less scientifically plausible solution than FTL or interdimensional travel. At that point we're just discussing comic book plots. If you believe we live in a universe that runs by comic book rules that's fine - it seems a depressing number of people here do, but there isn't much viable, intellectually grounded discussion to be had about that. You either agree with it or you don't. I mean hell, let's throw Jacques Valee onto the pile and say maybe UFOs/aliens are fae taking on a modern form in order to feed upon humanity's collective fear of the other. Makes about as much sense as time travel.

constantcrying 3y ago

Time travel backwards is causality breaking, which is a far, far more important physical principle than relativity. Time travel forwards is quite simple though, but less exciting.

jpadkins 3y ago
we can't rule out time travel forward on Earth. There is geological evidence of civilization destroying events 12k years ago, possibly more. I've often thought about why it took 300-400k years to go from fire to agricultural-civilization, then tech takes off in under 5k years from that point. What if the time from fire to civilization was faster, but those civilizations were wiped out (by geological, astrological or self-inflicted reasons)?
- phyrex 3y ago
  There’s good evidence against that. All the easily mineable resources that a civilization needs to build more advanced technology will be used up by the first civilization. I’ve heard it said that if we destroy our current technology there will be no way to rebuild it because there’s no way to mine the resources to build it back up.
  - ryandvm 3y ago
    Today's landfills are tomorrow's mines.
  - jpadkins 3y ago
    Yes, I've read that without easily accessible surface level coal, there is no industrial revolution. Maybe the advanced past civilizations were based in what is now called Africa or Indonesia, and the UK was some remote frozen place where it wasn't worth it to mine the surface coal?
- Shawnj2 3y ago
  From what I’ve heard it’s completely plausible for pre industrial human civilizations to have existed and been wiped out in the past but anything past that point would leave things like heavy metals we could detect in the geological record.

rdtsc 3y ago

Since the earth, and the whole solar system, along with the galaxy are moving through space, I can imagine some clever scientist discovering time travel, firing up they time machine, only to then find themselves in vacuum of space in a place the earth had long passed by already. Others try to calculate and predict the position. But they didn’t use enough floating point precision bits and ended up in the earth’s crust or somewhere in the ocean.

StrictDabbler 3y ago
There's an Isaac Asimov story from the 50's that I wonder if you've read. It's called "Blank!" In the story the scientist takes a friend forward 22 hours, but outside the time machine door there's nothing. Total darkness. The friend asks if the scientist forgot the movement of the Earth and the galaxy, but the scientist assures him that no, that motion has been accounted for. Instead it appears they've arrived between quantum periods, stuck forever out of phase with ordinary time like an elevator stuck between floors and frozen by the lack of momentum. I ask because that's the first story I read that drew attention to needing to travel in space to keep up with the planet.
- rdtsc 3y ago
  Thanks for the suggestion, I was not aware of "Blank!". What inspired me to write the comment is was thinking about time travel and how people in movies and stories seems to always materialize on a nice level surface, somewhere in a building with the their feet exactly on the floor, in a nice meadow outside the city, on a sidewalk etc. Then, remembering how earth and galaxy move through space I thought how extremely hard would be to get a safe set of future spacetime coordinates to land on.