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Does decay of particles give evidence of time being real?

  1. Feb 15, 2014 #1
    Consider our universe but with only two particles, say two protons. Inevitably they would orbit mutually about one another. As such, the time evolution of this trivial system would be cyclic, forever repeating their monotonous movement. This suggests that time is not absolute. It may not even be relevant.

    Oh, but wait. Don't protons have the potential for decay? So, the action of decay confounds the otherwise cyclic nature of even complex systems. It acts to introduce a stochastic non-reversible characteristic to the system - leading to time being absolute.

    Regardless of how long this may take, doesn't decay give evidence of the real existence of absolute time?
  2. jcsd
  3. Feb 15, 2014 #2


    Staff: Mentor

    Well since they are the only two particles, and nothing can observe them, how would you know they would do anything at all?

    And since protons are charged then we would have photons as well.

  4. Feb 15, 2014 #3


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    Why would they oscillate around each other? supposing there was EM interaction, they would repulse each other.... Also what do you mean by time not being absolute or relevant? absolute time is the idea that transforming the coordinate system will not affect time..the relevant is that time is affected. So you could still affect time.

    Also how do you imagine oscillations in that system?

    Also protons don't decay (unfortunately). maybe a bound system of p-p would "decay" because it's unstable (if they were interacting via strong force).
  5. Feb 15, 2014 #4


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    I don't know, because I don't know what you mean by "absolute time". But if you aren't familiar with the cosmic ray muon lifetime measurements, you may find them interesting. Google, and search the relativity forum here.
  6. Feb 15, 2014 #5
    I need to clarify:

    I casually choose two protons because I wanted a physical system that would have a cycling behavior, on a classical realm. I thought their mutual electric field would repel each other, while their masses would compel them to be mutually attractive albeit at a greater distance. I imagined they might eventually settle into a common orbital state.

    As I understand, "relative time" is occurring when a system is evolving but its parametric value is dependent upon the chosen observer. As such, systems that are reversible or cyclic are manifesting relative time.

    In contrast, "absolute time " is manifesting when it is invariant to any arbitrary observer. Time is absolute when a system is evolving in a fashion that is not cyclic or non -reversible.

    I wanted particles that could decay because that stochastic mechanism is truly random, so it is not cyclic nor reversible.

    It seems to me that decay introduces a mechanism that is non-reversible. The heart of my thesis is that decay mechanism may attest to time being real and absolute.

    Perhaps may choice of protons is poor. Instead consider particles that decay.
    Last edited: Feb 15, 2014
  7. Feb 15, 2014 #6
    You are imagining too much. It's a wonder this thread has made it thus far considering your premises and conclusions.
  8. Feb 15, 2014 #7


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    So you are talking of t-transformation invariance in the lagrangian under transformation to [itex]t \rightarrow t+t_{0}[/itex]?
    I still don't get your point, even if I think of something different than a particle. For example, the earth going around the sun, and suddenly due to a mechanism, the earth explodes into thousands of pieces. What's the problem there?

    The interactions of the particles have the T-symmetry (at least when you don't have CP-violation). So?
  9. Feb 15, 2014 #8


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    No. Time is not absolute, it is relative. Even particle decay obeys this. For example, muons created in the upper atmosphere shouldn't have a long enough lifetime to be detected at sea level. However, after they are created they are moving at relativistic velocities and due to time dilation they live long enough to make it to our detectors here on the ground before decaying.
  10. Feb 16, 2014 #9


    Staff: Mentor

    I apologize for my inattention.
  11. Feb 16, 2014 #10


    Staff: Mentor

    The repulsive electromagnetic interaction is always orders of magnitude greater than the gravitational attraction for two protons. They don't orbit each other.

    No, reversible or cyclic systems have no clear arrow of time. This has nothing to do with the chosen reference frame and relativity.

    No. Time is absolute if there is a reference frame in which the laws of physics are different from all other reverence frames. The arrow of time (reversibility) is a separate concept.

    Protons don't decay. There are plenty of other particles that do.

    The heart of your thesis is wrong. Particle decay is completely compatible with relativity. Relativity in no way implies reversibility.

    Yes, it was a poor choice, but far from the biggest problem. You need master the basics before jumping in with this kind of thesis. You are trying to do gymnastics before learning to walk.
    Last edited: Feb 16, 2014
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