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Mater and energy creation?

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  1. Jan 27, 2015 #1
    how can it be that mater can never be created nor destroyed. I just don't understand
    I was taught that both energy and mater can never be created nor destroyed yet they are interchangeable.
    to me this sounds like a direct contradiction of its self
    am I missing a major fundamental.
    Evenus1
     
  2. jcsd
  3. Jan 27, 2015 #2
    Matter and energy aren't interchangeable. Rather, matter is a form of energy, but there are other kinds of energy than matter. Matter can be converted to other forms of energy, so it can be created and destroyed. Energy cannot be created or destroyed. The big bang is a possible exception--but we don't understand enough to really say.
     
  4. Jan 27, 2015 #3
    is the big bang not beloved to be a dip in an multiverse plane of energy that caused an expediential reels of energy in a un comprehendible time span
     
  5. Jan 27, 2015 #4

    Drakkith

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    Staff: Mentor

    Matter can be created and destroyed. Mass and energy cannot, however. And it's not that mass and energy are interchangeable, it's that a quantity of energy has a certain amount of mass associated with it, with the equation e=mc2 serving to figure out how much. For example, if I add 1 joule of energy to a system, the system gains 1.1126500560536 x 10-17 Kg's of mass.

    Chemical and nuclear reactions are often given as examples of mass turning into energy, but this is not true. For example, if an atom decays and emits radiation, it is typically said that some of the mass of the atom has 'turned into energy'. But if we look at the atom prior to decay as a single system, and the atom plus the light after the decay as another single system, then BOTH systems have exactly the same mass.
     
  6. Jan 27, 2015 #5
    a lot of people believe a lot of strange things about the big bang, but nothing is proven
     
  7. Jan 27, 2015 #6

    Drakkith

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    No, that is absolutely not what the big bang is believed to be. It's also a little off topic to talk about the big bang. Let's stick to the original topic please.
     
  8. Jan 27, 2015 #7
    but (I am still in secondary school) does qm not explane this
     
  9. Jan 27, 2015 #8
    sorry I am just really interested in all of these kinds of theories and do a lot of research in to them but I sometimes come up a bit short
     
  10. Jan 27, 2015 #9

    Drakkith

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    Staff: Mentor

    The big bang? No, QM doen't explain it. Mass-energy equivalence? I'm not sure how QM touches on that.
     
  11. Jan 27, 2015 #10
    One source of confusion is that some texts give an incorrect definition of mass as the quantity of matter.
     
  12. Jan 27, 2015 #11
    This law does not apply to the creation of the Universe. That is the beauty of cosmology.
     
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