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Time's arrow

  1. Jul 16, 2010 #1
    does the various arrows of time correlated?
    or how many of them are correlated?
    1-arrow of time in radiation
    2-thermodynamics arrow of time
    3-cosmology arrow of time
    4-quantum mechanical arrow of time
    5-CP violation in weak interactions (!?)

    whats do you thinks?
  2. jcsd
  3. Jul 18, 2010 #2
    Could you re-phrase the question?
  4. Jul 18, 2010 #3
    what of this arrows are result of other?
    for example why the the thermodynamic is result of cosmology time arrow?
  5. Jul 19, 2010 #4
    Ah, you've been reading Wikipedia!

    The arrow of time is merely a reference to the fact that time (to us) appears to move in one direction only, from past to future or cause to effect.

    The fact that this process can be observed in different branches of the subject and in some cases correlated between them is merely an artefact of our arbitrary separation of those subjects.

    What you are asking is akin to the question 'Is the 2 in
    K.E = 1/2Mv^2 the same as the one in c=2Pi*r?'
  6. Jul 21, 2010 #5
    I like this time's arrow concept. It would seem to me that if the universe started out as a singularity, then time couldn't be the fourth dimension.

    How can the fourth dimension begin before a first?

    Why doesn't relative time dilation have an effect on mass with vectors perpendicular to a velocity?

    Isn't special relativity better explained by a variance in time through an angular perspective? Everything seems to strike an object at the speed of light, which would mean time couldn't be the fourth dimension. The issue would be vector based.

    Only one value is needed to reposition a video (move forward or backward in time). Time is single dimensional with regard to audio and video moments.

    Energy has no relative-time. Yet, it traverses a span. Velocity still exists. Couldn't time feed both velocity and relative time?

    Gravity creates acceleration but two objects can have the same radius to a body and different relative time dilation. One was simply released above the other. Velocity being the only cause of time dilation would lead one to believe that time is one-dimensional.

    If time were actually the fourth dimension, wouldn't this rise energy through time to infinity? Every Planck moment holding a universe would be costly.

    Now, if time is a current, a one-dimensional issue, doesn't gravity suddenly become understandable? If time is a current and there is potential, a resistive element must exist. And gravity exits any amount of mass.

    It seems to me, that all the forces in physics unifies, if we alter our perspective of time.
  7. Jul 21, 2010 #6


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    The time arrow resulting from statistical mechanics is the most relevant one. It determines how the information is stored, and therefore, how we, as humans, perceive the world.

    Second Law of Thermodynamics is the great example of this. It's not that th entropy is always increasing. It's that to store information, it needs to be increased. And that means, the direction in time which leads to increasing entropy is the future direction.

    Of course, since expansion of the universe is the reason for increasing entropy, all other kinds tie into it, and we have a persistent "time flow".

    It all makes a lot more sense in context of Many Worlds Interpretation. Under MWI, the global entropy is conserved, but entropy of each world is increasing.
  8. Jul 21, 2010 #7
    I'm of a mind that reality is based on a single value, 'c'. Things are only real when they meet the value of it---even the conduct of a static state. I would only be shocked if things, didn't, pop in and out of existence. I simply don't buy into MWI. In my mind, it would kill cause and effect, equal and opposite. Physics seems to work very well with its predictions.

    For every static state, there must be a conductive flow at 90 degrees. Inertia is supported by time and has velocity, the factor used to determine the static state. Inertia is a static state for a potential kinetic possibility and something is at 90 degrees from it. If time is the flow that holds the static state, then suddenly Lorentz’s equation makes perfect sense (still meaning time is the first dimension). There must be time flowing equal to the energy---this is profound.

    I think there are many alternate realities based off another value to the speed of energy. A dream has a lower value (concepts). We can't fit into them, we have too much energy.

    We have a universe and we seem to know where the origin is. This is a titanic understanding. It means beyond a doubt that universes can be created---we have one.
    Last edited: Jul 21, 2010
  9. Jul 21, 2010 #8


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  10. Jul 21, 2010 #9
    I apologize for concept of ‘c’ being the single value for realty. Though, I feel this offers nothing new, noting that Einstein first coined the phrase, relative-velocity. Special relativity has been under test for decades now. No one I know argues that energy doesn’t transfer at the speed of energy, and that this would be a future expectation as well.
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