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Energy conservation ?

  1. May 27, 2008 #1
    Considering UNIVERSE as a system , then are the black holes the elements that are present in the system so that the energy of the system remains conserved ?

    Is there any information on how black holes came into existence ( is it a balancing act of nature ) ?

    Can (energy conservation) principle be applied at the time of BIG BANG because the only way i think universe could have started if there was extra energy which couldn't balance itself ?
  2. jcsd
  3. May 27, 2008 #2
    1- Yes
    2- A relatively well understood process.
    3- Unknown as to the specific causation, but it could be accepted that energy was present, which supposes that energy was pre-existant with respect to the "event"
  4. May 27, 2008 #3
    Then as my imagination goes The question should be What came first, Black Hole or Universe ? as considering Black Hole as a system and to balance the system , Universe formed .

    Is energy conservation valid for a black hole ?
  5. May 28, 2008 #4
    I have limited personal professional knowledge to draw upon but I seem to recall that of those who study this, the nature of the universe at it's beginning is a subject of considerable debate, so I would suspect that the answer to your questions could be speculated yes or no depending on who you talk to.
    There just doesn't seem to be enough evidence to draw a majority concensus regarding the creation of the universe; thus different theories abound, each with their own merits and each with their own many unknowns.
    It is, however, generally agreed that regardless of which theory one ascribes to regarding the "early" universe, the actual physics were both very extreme and do not exist today in that same sense. Most professional agree on that.

    With a "classical" black-hole, the requirements of formation demands a situation that likely could exist only after the universe was "created", so the universe comes first, then the black-hole.
    On the flip-side, one could just as easily suggest the the gravitational force was so concentrated at universe creation, that the "mother" of all black-holes was created and is somehow responsible for everything else.

    In short, it is easy to see there are many unaswerable questions since the "how" of the formation of the universe itself is not known and thus far has been very illusive in understanding or emprical evidence.
  6. May 28, 2008 #5
    Can someone enlight me? I heard something about the "vacuum energy" causing the Casimirs effect or Hawkings Radiation. New particles are popping out into existence, but doesn't that contradict the conservation of energy?
  7. May 28, 2008 #6
    Think on this... if a particle "pops into and out of existance" does it not balance itself. It is, in a sense, self-conserved.
    In my mind, virtual particles represent a certain "magic"
    That is, virtual particles do influence what we call "reality" The influence potential is very small, as virtual particles exist for such a short period of time to have very limited consequence on what "really happens" but the influence is there nonetheless.

    For example, a virtual electron might appear, but has no inherent ability to sustain itself long enough to to "bind" to a proton; thus making an atom impossible.
    This ultra short-lived nature of virtual particles might be manipulated through special physics techniques such as "frame-dragging", so we will see what might haqppen.
  8. May 28, 2008 #7
    what youre saying is that it pops in and out of existence so fast that it causes no hassle? That it basically borrows energy from the future and repays it later when it disappears again?

    But then what about Hawkings radiation? And Casimirs effect, the plates move. That means the particle exerted force on the plate no? Giving it some of its energy, but if the energy was to be conserved, the plate would have to somehow lose that energy and perhaps *teleport* back into its previous position.
  9. May 28, 2008 #8
    In the Casamir effect you don't have a true vacuum because the plates are imposing boundary conditions on the field. I'm really fuzzy on this but I think there are non-zero eigenvalues of the Hamiltonian if the field is not in a true vacuum state-- so the energy does come from somewhere, it comes from the field itself. Putting a ??? here though because I'm unsure.
  10. May 29, 2008 #9
    Perhaps this can be of some help:

    There are many observable physical phenomena resulting from interactions involving virtual particles. All tend to be characterized by the relatively short range of the force interaction producing them. Some of them are:

    The Coulomb force between electric charges. It is caused by exchange of virtual photons. In symmetric 3-dimensional space this exchange results in inverse square law for force.
    The so-called near field of radio antennas, where the magnetic effects of the current in the antenna wire and the charge effects of the wire's capacitive charge are detectable, but both of which effects disappear with increasing distance from the antenna much more quickly than do the influence of conventional electromagnetic waves, for which E is always equal to cB, and which are composed of real photons.
    The strong nuclear force between quarks - it is the result of interaction of virtual gluons. The residual of this force outside of quark triplets (neutron and proton) holds neutrons and protons together in nuclei, and is due to virtual mesons such as the pi meson and rho meson.
    The weak nuclear force - it is the result of exchange by virtual W bosons.
    The spontaneous emission of a photon during the decay of an excited atom or excited nucleus; such a decay is prohibited by ordinary quantum mechanics and requires the quantization of the electromagnetic field for its explanation.
    The Casimir effect, where the ground state of the quantized electromagnetic field causes attraction between a pair of electrically neutral metal plates.
    The van der Waals force, which is partly due to the Casimir effect between two atoms,
    Vacuum polarization, which involves pair production or the decay of the vacuum, which is the spontaneous production of particle-antiparticle pairs (such as electron-positron).
    Lamb shift of positions of atomic levels.
    Hawking radiation, where the gravitational field is so strong that it causes the spontaneous production of photon pairs (with black body energy distribution) and even of particle pairs.
    Most of these have analogous effects in solid-state physics; indeed, one can often gain a better intuitive understanding by examining these cases. In semiconductors, the roles of electrons, positrons and photons in field theory are replaced by electrons in the conduction band, holes in the valence band, and phonons or vibrations of the crystal lattice. A Virtual_particle is in a virtual state where the probability amplitude is not conserved.

    From: http://en.wikipedia.org/wiki/Virtual_particle
  11. May 31, 2008 #10
    By my imagination we will never be able to know how universe got created even if we get something out of LHC because we will be still asking how did the particles formed, how did Higgs boson formed, where did that come from , we will be always looking for answers & we will go deep in that but still we will be asking "HOW did that particular thing came into existence" , we will never know how deep the hole goes coz if we say everything came from nothing then how did that nothing came . I think its better to manipulate what we have got rather than searching for GOD
  12. Mar 2, 2009 #11
    I think i might understand your problem. You are right that energy is conserved.
    That means that the total energy of an independent system is constant. It doesn't mean that it is zero.

    There is a greater than zero, constant amount of energy in the universe.

    Why this is true is another question...

    Some people think that there are other universes that have "anti-energy" and that the total energy of all universes is zero.

    Personally, I think that I'm going to worry about how to feed everyone on Earth before moving on to the more trivial stuff...
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