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Cosmological constant

  1. Sep 26, 2010 #1
    The cosmological constant has been a debated issue for a century... What if the constant is a ratio of the Force of dark energy to the force of gravity just like in a spring where the resistivity is the ratio of the force of gravity and the spring.
  2. jcsd
  3. Sep 27, 2010 #2
    Don't believe that will work as the cosmological constant is called that because it's one of the few quantities that is frame independent...light light, it has the same value in all observer frames....Whatever goes on in the vacuum seems pretty much a mystery....
  4. Sep 27, 2010 #3
    You are right.. it is a very elusive idea that no one has been able to answer. Until we understand how the expansion of the universe takes place and by what medium, einstein's equation wil not have a deeper meaning just a mathematically one.
  5. Sep 27, 2010 #4
    Hi Ikoro,
    The question is: could Einstein have been correct when he speculated of the existence of a Cosmological constant? In nature there exists two kinds of energies which are equivalent and opposite, the gravitational and the kinetical energies. These two energies or forces always try to find an equilibrium eg. the movement of the moon around the earth. The basic quantity of energy is a quantum particle E = h f, where h stands for a Plank constant and f stands for the frequency of a photon. Since the quantum particle is the basic form of energy, it cannot loose any energy and since it both moves at the speed of light and it is affected by gravity, it must consist of both gravitational and kinetic energies. Thus the basic form of energy consists of two equal but opposite forces, one gravitational and the other kinetical. Could it be that the kinetical force contained in the quantum particle is the Einstein's Cosmological constant?
    Yours Cosvis.
  6. Sep 28, 2010 #5

    Weinburg recently was quoted as saying " Einstein's biggest mistake was in thinking the Cosmological constant to be a mistake
  7. Sep 29, 2010 #6
    Hi Yogi,
    Thank you for your supportive reply. I think Einstein had the basic principles for solving the problem between gravity and the quantum but was distracted by the other scientific investigations of his time that misled him to accept the idea that he had made a mistake by postulating the "Cosmological constant". At the time Hubble rightly discovered that the redshift of the light coming from distance galaxies varied according the distances of the galaxies from earth. This redshift was interpreted to be a Doppler redshift and thus the idea was firmly fixed that the universe was expanding. If Einstein had refused to negate his cosmological constant, he could have interpreted the redshift to be due to a gravitational redshift and thus his believe in a constant universe could still have been true.
    Yours cosvis.
  8. Oct 1, 2010 #7
    The idea of an unchanging universe actually creeps in the back door of an accelerating universe - much recent data indicates the present universe is in a c^2/R
    de Sitter expansion - so at the Hubble limit things don't change - the Hubble constant is really constant - the recessional velocity is c which is the same rate at which the Hubble sphere would be growing in a static universe - so photons emitted at the Hubble limit in our direction are never seen - to all appearances the universe looks frozen
  9. Oct 2, 2010 #8
    so is there or is there not a constant?
    does observational data agreed with the mathematical equations?
  10. Oct 2, 2010 #9


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    Observations tell us that the universe is accelerating in its expansion at the present day, so there must be some sort of 'dark energy'. Whether this is a cosmological constant, some dynamical energy content, or some modification of gravity is still under debate.
  11. Oct 4, 2010 #10
    It's more likely to be some sort of energy that does not relflect or emit light than some sort ether or cosmological constant postulated by people such as einstein or newton.
  12. Oct 4, 2010 #11
    Perhaps at some fundamental level, space is quantized - and the relationship between space and time is such that for each new second of cosmic age, there is a new dx, dy and dz - a sort of cosmological Minkowski dynamic unification which results in an intrinsically accelerating volume - this corresponds to the units of G (volumetric acceleration per unit mass). Ergo, no dark matter is required -

    But - if thats the case why were there periods when the Hubble sphere did not appear to follow the present expansion trajectory - to that, there is no good answer - one might note however, that current estimates of the Hubble limit are now generally interpreted as a small volume of a larger universe which may approach infinite extent - If the Hubble sphere with its condensed matter content had an origin some 13+ billion years past - perhaps it behaved differently from the rest of space during its early development due to its matter density.

    I guess I am always skeptical of ad hoc fields such as dark matter - so I make up my own ad hoc solutions
  13. Oct 4, 2010 #12
    Hi to all,

    The universe must be full of light travelling in all direction. It is only observable to us when it directly hits us. When one observes photons or light travelling perpendicular to our sight, we do not observe them. They are virtual particles or photons not directly observable but can be explained by quantum mechanics. Since all photons have equal and opposite gravitational and kinetic elements or energies, they could be regarded as a possible candidate to be the constitutional element of the dark matter, a possible universal ether that constitute the cosmological constant. May be it is the quantum particle, the particle with the least quantity of energy, that is also the Higgs Boson particle, not yet discovered?
    Yours cosvis.
  14. Oct 4, 2010 #13
    I always encourage new solutions, provided they make either logical/mathmatical sense. I'm glad we love in an age where scientific theories can be put forth without the threat of being labelled a heretic, and possibly killed for your ideas.
  15. Oct 7, 2010 #14
    ditto - perhaps one of the joys of sciece is to realize how lucky we are to have so many unsolved problems to amuse us - how boring it would be if we already knew all the answers.
    That is not to say we should condemn the standard theory. If something better fits the facts, then one speculation must give way to another. Much work and thought has gone into finding a rational explanation of the universe.
  16. Oct 11, 2010 #15
    Speculating, I think that the higgs field is the same as dark energy.
    1) we speculate particles gain masses from the interaction with the higgs field. According to einstein gravity is due to stress-energy tensor. We can assume that this field reacts to larger objects differently. So we can assume that the curvature in space is basically the tensor coupling with the tensors of the higgs field( having in mind the basics of stress and energy).
    2) dark energy is nothing more than a misnomer because if the higgs field is responsible for mass in certain particles( dependent on their interaction) then,as galaxies are born and die ,energy has to be transformed so it could be transferred to the vaccum. And the expansion we see is just the higgs field gaining energy and since E=mc^2 the universe will have to expand. SO in short we mistook and energy gaining higgs field for dark energy.
  17. Oct 11, 2010 #16
    it is just like energy, If we expanding the lorentz constant using taylor's expansion, we will get mc^2 and 1/2mv^2. They re all of the same energy just at different speeds ,so dark energy might just be the higgs field under pressure or force or even energy transfer.
  18. Oct 11, 2010 #17
    Making speculations is OK, but then there comes the part in which the galaxies are "born" and then "die". We don't see any kind of process that can be described in this way. The process should look like matter/energy appearing from or disappearing to nowhere.
  19. Oct 11, 2010 #18
    I wasn't not clear enough... stars and neutron stars collapsing into black holes and emitting radiation and we know that the transformation of energy is never 100percent. I guess the question remains..what supplies the energy of the expanding universe?
    We can take example that the birth of galaxies do add energy to the vacuum resulting in a transfer of energy(unknown). Resulting in the gaining of energy and momentum of the higgs filed resulting in the constant expansion. Now this speculation will depend on if the birth of galaxies and stars would have to occur at the same magnitude over time to maintain the linearized expansion of the universe. Since we do not have data or theories explaining where the higgs field energy comes from or the energy responsible for the expansion comes from. SO it is an open ended question left for speculation.
  20. Oct 11, 2010 #19
    I have posted this before - seems fitting here also.

    The Late John Wheeler once offered a lovely but chilling paradox: “At the heart of everything is a question, not an answer. When we peer down into the deepest recesses of matter or at the farthest edge of the universe, we see, finally, our own puzzled faces looking back at us.”
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