Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Question regarding the arrow of time

  1. Jun 1, 2007 #1
    How about this idea...
    With regards to this thing called, the arrow of time!

    Could the universe have different arrows of time for different regions of the universe?
    This regions of the universe where the Earth is, the arrow of time is going say forward.

    Could there be other far off regions of the universe that have the arrow of time going backwards?

    Imagine if the universe was composed of a forward arrow of time sub-universe and a backward arrow of time sub-universe superimposed upon eachother!

    If there were galaxies in regions of the universe that have the arrow of time going backwards,
    from our perspective instead of the stars in those galaxies emitting light, they would be absorbing light,
    and therefore their light would not be visible to us here in this forward arrow of time region of the universe.
     
  2. jcsd
  3. Jun 4, 2007 #2

    Chronos

    User Avatar
    Science Advisor
    Gold Member
    2015 Award

    What would be the observational consequences [to us] of these different 'arrows of time'?
     
  4. Jun 4, 2007 #3
    The observational consequence would be if we went somewhere and found clouds of random looking debris and gas coalescing into unlikely arrangements, light bizarrely focusing itself onto dwarf stars until they bloat and evaporate into uniform gas clouds, planets with dirt that suddenly arranges itself into big living organisms that shrink and then are taken into even newer organisms..

    Nothing stopping this happening, it's just incredibly improbable.

    What I can't explain is why it seems our universe was far, far more improbable than that when it began (more so even than the anthropic principle justifies).
     
    Last edited: Jun 4, 2007
  5. Jun 4, 2007 #4
    What way does the arrow of time point in a vacuum?

    Could it be that there is no arrow of time in a vacuum?

    Could the universe have different arrows of time for different regions of the universe depending on the type of matter there?

    This regions of the universe where the Earth is, the arrow of time is going say forward, and lets call the type of matter here, forward matter.

    Could there be other far off regions of the universe that have the arrow of time going backwards?
    And the type of matter in those regions could be known as reverse matter.

    Imagine if the universe was composed of a forward arrow of time sub-universe and a backward arrow of time sub-universe superimposed upon eachother!

    If there were galaxies in regions of the universe that have the arrow of time going backwards, from our perspective instead of the stars in those galaxies emitting light, they would be absorbing light, and therefore their light would not be visible to us here in this forward arrow of time region of the universe.
     
  6. Jun 4, 2007 #5
    I reckon that they would be difficult to observe because from our perspective, they would be absorbing light.

    Maybe, the effects of their gravitational field could be observed.

    Maybe, if theoretical physicists were to work through the mathematics, the might expect to find certain results that would be complementary to the observed structure of the universe.
     
  7. Jun 4, 2007 #6
  8. Jun 6, 2007 #7

    Chronos

    User Avatar
    Science Advisor
    Gold Member
    2015 Award

    As, it seems, do I [dismiss the idea].
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Question regarding the arrow of time
Loading...