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Can matter/energy be eternal?

  1. May 27, 2015 #1
    I was listening to Lawrence Krauss. I quote roughly what he said,

    'Our universe had a beginning. But it is not required, though. It could well have been eternal.'

    My question is,

    Can matter/energy be eternal? If yes, has any mechanism been proposed for such an existence?
  2. jcsd
  3. May 27, 2015 #2


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    I am not sure what you mean by eternal, but matter and energy are conserved. This means that although they may change forms and states, the total energy and the total mass in the universe taking into accounts all forms and states of energy and matter, remains the same.

    If by eternal you mean not to change form and states, for example if we have the human body, how can we make it not to change form and state and remain always young, then i simply dont know the answer.
  4. May 27, 2015 #3
    When time goes to infinity, it is possible that matter and energy will turn into something which we do not define as energy nor matter anymore. For example what if another universe collided with ours, created a big crunch and changed all the laws of physics somehow? Just a random idea.

    Matter is definitely not eternal since it can exit whatever state it has within the particle resulting into an increase of what we define as energy.
  5. May 27, 2015 #4
    By eternal, i mean,

    Something that does not require a beginning ( see lawrence's quote).
    Something that always exists.
  6. May 27, 2015 #5
    As far as I know the laws of physics were different in the beginning of the big bang. Thus it has a beginning. Correct me if I'm wrong.
  7. May 27, 2015 #6


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    As Delta2 has eluded to, you need to first figure out what "conservation laws" means. And then figure out if your idea of something being "eternal" matches the concept of these conserved qualities/quantities.

    I strongly suggest, unless people want this thread to run into trouble with the Mentors, that we do not make speculation of what might happen on the outer edges of time.

  8. May 27, 2015 #7
    I am not asking for speculations. I just want to know if there is a well developed scientific model for eternal material existence?
  9. May 27, 2015 #8


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    And you seemed to be ignoring the REST of my post regarding conservation rules. Can you explain why?

  10. May 27, 2015 #9
    It should be noted that "time" is currently understood to have started with the Big Bang. As such, the matter and energy in this universe is indeed eternal in that sense.
  11. May 27, 2015 #10

    Actually, i didnt want to argue with a person who has such a huge number of posts to his credit....

    Since u have asked...

    I think, conservation laws are 'relations' between already existing entities. So, they come somewhat later in the explanation of eternal existence.
  12. May 27, 2015 #11
    So, does it mean there was really 'Absolutely Nothing' prior to Big Bang....
  13. May 27, 2015 #12
    "Prior" is a something that presumes a time line. If you assume the correctness that time originated at the Big Bang (which might or might not be actually true), then the question "what was before Big Bang" is a nonsensical question.
  14. May 27, 2015 #13


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    What does that mean? What is this point that they come in "later"? Later than what? Later in what?

    Are you saying that conservation of mass/energy didn't exist at some point in our universe, and then it appeared suddenly? The same with conservation of charge and momentum, etc?

  15. May 27, 2015 #14
    I have read (may be wrongly) that mass, charge etc. originated some time after the big bang happened. If they can originate at a later time, it is possible that the laws that govern inter-relations between mass, charge etc. emerged even later.
  16. May 27, 2015 #15
    Matter indeed wasn't immediately there after the Big Bang, it came shortly after. But the energy that those particles came from (since particles can be created from energy, and vice versa) existed right from the beginning.
  17. May 27, 2015 #16
    But.....we know only of our time. What if some other kind of time existed prior to bigbang.

    If such is the case, i think, indeed 'eternal material existence' has some kind of different meaning to it.
  18. May 27, 2015 #17
    But that is pure speculation, there is no evidence for something like that. Keep in mind, Physics works off empirical evidence. The rest is metaphysics.
  19. May 27, 2015 #18
    Is it known for sure that the energy that existed at the very first instant of big bang is the same energy we witness today?
  20. May 27, 2015 #19
    The energy conservation has never been seen to be violated.
  21. May 27, 2015 #20
    While time is how we relate to movement of space, saying that time began at the big bang means that the structure of space came to be at that point. That does not mean that whatever existed before the big bang could not change. Nor do I believe that energy can be defined without time or space. Thus according to OP's definition of eternal, energy is not eternal since it requires the beginning of space and time to fit its definition.
    Last edited: May 27, 2015
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