7 ms·

Or, about 60 million years after it happened...

by nicwolff 5y ago

rootlocus 5y ago
It really is mindblowing when you think it actually happened 60 million years ago.
- Keyframe 5y ago
  What we're doing now might be visible as 'now' to someone 60 million years into the future, albeit a bit down the road from us.
simonh 5y ago
There is a frame of reference in which the event and the observation are simultaneous.
- jb1991 5y ago
  I'm rather confused by this statement. Can you elaborate?
  - eru 5y ago
    If you move fast enough, weird things happen in special (or general) relativity. Similarly, if you somehow managed to send something even slightly faster than the speed of light, there's a frame of reference in which you have send it backwards in time.
  - AgentME 5y ago
    The photons we observed from the death of the star experienced no time between coming from the star and arriving to us.
    - jb1991 5y ago
      Are you saying that if I’m in a spaceship, and I travel at the speed of light as I leave that star at that moment, and then I arrive here at earth, with my fellow photons traveling next to me, that I will have arrived at earth instantly without observing any time spent in transit?
      - coremoff 5y ago
        That is correct. Obviously, given that, you would have no way of stopping, so your arrival would be abrupt (ignoring whatever magical affects would be necessary to accelerate a massive object to light speed).
        jb1991 5y ago
        So in other words, if you can travel at the speed of light, you can be anywhere in the universe instantly, and never have to wait to get anywhere? I will say, that certainly makes no sense to me.
        coremoff 5y ago
        it's a big "if"; it's not possible for objects with mass to accelerate to light speed. If you were able to do so, yes you could "get" anywhere in zero subjective time - as mentioned earlier, since no time passes for you, there would be no way for you to decide that you wanted to stop travelling at light speed - you would end your existence by impacting something. > that certainly makes no sense to me Humans, as a species, aren't experienced with relavitistic effects; we have no useful inherent intuition as to how things behave at these sorts of speeds. Most of us have to accept the maths and the experiements that demonstrate that our understanding of this behaviour is accurate.
      - dav_Oz 5y ago
        This the reason why photons have no rest mass. And you having a rest mass cannot ever reach the actual speed of light, only a factor of <1. If you were to travel with 95% of the speed of light your rest mass would increase by 3.2x ... at 99% by 7.1x at 99.9% by 22.4x and at 99.99999% by 2240x and so on. The Lorentz factor is infinite for the speed of light. Time "stops" and the object contracts to "zero" at c. https://www.1728.org/reltivty.htm https://www.1728.org/reltivty.htm
  - amelius 5y ago
    https://www.youtube.com/watch?v=wteiuxyqtoM https://www.youtube.com/watch?v=wteiuxyqtoM
- junon 5y ago
  Yes - when you're the star itself, I suppose. That's not what GP is suggesting at all...
  - simonh 5y ago
    I don't think GP is really suggesting anything, just trying to make a clever comment with no substance.
- lostmsu 5y ago
  This is definitely false according to SR, because the event is on the past light cone of the observation.
tsimionescu 5y ago
Well, from the perspective of the photons, the explosion happened just an instant before they hit the telescope, and they barely even travelled a single Planck length to get from the exploding star to the telescope. Events that are so far apart in space and time don't have fixed periods (or distances). To observers in other galaxies that are moving fast relative to both us and the star, the time between the explosion and our detection of it (were they able to perceive both) would also vary.
LinuxBender 5y ago
Perhaps one of their planets released a probe that will attach to a future intelligent life form and tell their story. [1] How many years until we potentially find it? [1] - https://memory-alpha.fandom.com/wiki/The_Inner_Light_(episode) https://memory-alpha.fandom.com/wiki/The_Inner_Light_(episod...
- ASalazarMX 5y ago
  That episode is great, but manipulating an unknown and unwilling alien brain always struck me as too dangerous. Maybe their Voyager equivalent reached the wrong aliens in the dark forest.
  - LinuxBender 5y ago
    The Enterprise crew agreed with you. They tried twice to sever the connection, nearly killing Captain Picard in the process.

Or, about 60 million years after it happened...

rootlocus 5y ago

It really is mindblowing when you think it actually happened 60 million years ago.

Keyframe 5y ago
What we're doing now might be visible as 'now' to someone 60 million years into the future, albeit a bit down the road from us.

simonh 5y ago

There is a frame of reference in which the event and the observation are simultaneous.

jb1991 5y ago
I'm rather confused by this statement. Can you elaborate?
- eru 5y ago
  If you move fast enough, weird things happen in special (or general) relativity. Similarly, if you somehow managed to send something even slightly faster than the speed of light, there's a frame of reference in which you have send it backwards in time.
- AgentME 5y ago
  The photons we observed from the death of the star experienced no time between coming from the star and arriving to us.
  - jb1991 5y ago
    Are you saying that if I’m in a spaceship, and I travel at the speed of light as I leave that star at that moment, and then I arrive here at earth, with my fellow photons traveling next to me, that I will have arrived at earth instantly without observing any time spent in transit?
    - coremoff 5y ago
      That is correct. Obviously, given that, you would have no way of stopping, so your arrival would be abrupt (ignoring whatever magical affects would be necessary to accelerate a massive object to light speed).
      - jb1991 5y ago
        So in other words, if you can travel at the speed of light, you can be anywhere in the universe instantly, and never have to wait to get anywhere? I will say, that certainly makes no sense to me.
        coremoff 5y ago
        it's a big "if"; it's not possible for objects with mass to accelerate to light speed. If you were able to do so, yes you could "get" anywhere in zero subjective time - as mentioned earlier, since no time passes for you, there would be no way for you to decide that you wanted to stop travelling at light speed - you would end your existence by impacting something. > that certainly makes no sense to me Humans, as a species, aren't experienced with relavitistic effects; we have no useful inherent intuition as to how things behave at these sorts of speeds. Most of us have to accept the maths and the experiements that demonstrate that our understanding of this behaviour is accurate.
    - dav_Oz 5y ago
      This the reason why photons have no rest mass. And you having a rest mass cannot ever reach the actual speed of light, only a factor of <1. If you were to travel with 95% of the speed of light your rest mass would increase by 3.2x ... at 99% by 7.1x at 99.9% by 22.4x and at 99.99999% by 2240x and so on. The Lorentz factor is infinite for the speed of light. Time "stops" and the object contracts to "zero" at c. https://www.1728.org/reltivty.htm https://www.1728.org/reltivty.htm
- amelius 5y ago
  https://www.youtube.com/watch?v=wteiuxyqtoM https://www.youtube.com/watch?v=wteiuxyqtoM
junon 5y ago
Yes - when you're the star itself, I suppose. That's not what GP is suggesting at all...
- simonh 5y ago
  I don't think GP is really suggesting anything, just trying to make a clever comment with no substance.
lostmsu 5y ago
This is definitely false according to SR, because the event is on the past light cone of the observation.

tsimionescu 5y ago

Well, from the perspective of the photons, the explosion happened just an instant before they hit the telescope, and they barely even travelled a single Planck length to get from the exploding star to the telescope. Events that are so far apart in space and time don't have fixed periods (or distances). To observers in other galaxies that are moving fast relative to both us and the star, the time between the explosion and our detection of it (were they able to perceive both) would also vary.

LinuxBender 5y ago

Perhaps one of their planets released a probe that will attach to a future intelligent life form and tell their story. [1] How many years until we potentially find it? [1] - https://memory-alpha.fandom.com/wiki/The_Inner_Light_(episode) https://memory-alpha.fandom.com/wiki/The_Inner_Light_(episod...

ASalazarMX 5y ago
That episode is great, but manipulating an unknown and unwilling alien brain always struck me as too dangerous. Maybe their Voyager equivalent reached the wrong aliens in the dark forest.
- LinuxBender 5y ago
  The Enterprise crew agreed with you. They tried twice to sever the connection, nearly killing Captain Picard in the process.