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Dark energy could be gravitons

  1. Jun 27, 2004 #1
    Dark energy could be the energy of a huge number of gravitons.
    As photons travelling from one galaxy to another redshift they could emit gravitons that adds to the dark energy total and so keep the density of dark energy constant.Also if the gravitons carry the colour force , like gluons,
    then they would be inhibited by other gravitons as they travel from one mass to another-they would lose energy to other gravitons and the force of gravity would be very weak by the time they reached a distant mass.
     
  2. jcsd
  3. Jun 28, 2004 #2
    Dark energy is defined as a hypothetical energy evenly filling the universe where there is no ordinary matter or dark matter. It is a more general idea of energy than the cosmological constant (energy balancing parameter in general relativity). The time derivative of dark energy is not zero. But unfortunately, cosmologists do not presently believe that photon can emit graviton. They are distinct types of force quanta. Photon is the quantum of the electromagnetic force and graviton is the quantum of the gravitational force. These two forces are not related although Einstein used to think so and he did try to unify gravity and electromagnetism but he never succeeded in this attempt. The Kaluza-Klein theory of 5th dimension is also another attempt to unify gravity and EM. This was forgotten but revived by the superstring theory to 10th dimension and M-theory to 11th dimension. Still graviton is not found by experiment. The reason why it is very difficult to detect graviton is that gravitons are the quantized waves of spacetime itself while photons are waves travelling through spacetime. To give an analogy using surfing, the photons are the surfers and graviton are the breakers.
     
  4. Jun 28, 2004 #3
    ANTONIO LAO:

    The reason why it is very difficult to detect graviton is that gravitons are the quantized waves of spacetime itself while photons are waves travelling through spacetime. To give an analogy using surfing, the photons are the surfers and graviton are the breakers.

    KURIOUS:

    I agree with this.But I still believe photons impart energy to dark energy.
    Dark energy has to come from somewhere!
    Since space-time as a whole is constant, if it imparts energy to matter then it must
    get some back too.
     
  5. Jun 28, 2004 #4
    The origin of dark energy is still a mystery. It is used to explain the forces of antigravity in an inflationary universe. An inflationary universe is a step more advanced timewise than the big bang singularity. There still no theory that can explain the singularity of the standard model of the big bang.
     
  6. Jun 28, 2004 #5
    In terms of theoretical developement, what views would have supported cyclical universes? If Singuarities are a not a end feature anymore from the possibiltiy of the action of Fission/fusion being detailled in blackhole creation?

    The collapse fo the balckhole signals other considerations, and needed to be geometrically consistent in the model explanations topological considered?

    How would you do that? :smile:

    We develope theorectical models in place of actual physics, in the hopes of being pointed in complete visualized summations one might have understood how the geometry of bubble inversion might comeout of expansitory modes, while entrophy understanding of those blackholes become geometrical defined.
     
    Last edited: Jun 28, 2004
  7. Jun 28, 2004 #6
    No need for a singularity at all.
    If the universe never got smaller than about 10^24 metres in radius then (using energy density is proportional to 1/ R ^ 4 for photons) the temperature of the cosmic microwave background would have been about 10^10K after 1 second -which current big bang theory says it was at a radius of 10^-35 metres.The pressure generated by this temperature could have enabled the universe to reach its current radius in 10^18 seconds - the current age of the universe.
     
  8. Jun 28, 2004 #7
    You have to understand the gravitational perspective is also being developed along side of critical density. That has to be done geometrically?
     
  9. Jun 28, 2004 #8
    Maybe we are back to dimensional problem of space? In a 1D universe, how many closest points does each point of this universe has? My answer is 2. In a 2D universe the number of nearest points is 4. For 3D, it's 6. For 4D, it's 8. For 5D, it's is 10. For 6D, it's 12. For 7D, it's 14. For 8D, it's 16, For 9D, it's 18. For 10D, it's 20.

    My idea is that the complete universe is like a figure 8 or [itex] \infty[/itex]. One loop contains all the antimatter and the other contains matter. If one loop decreases in radius the other increases in radius and vice versa. The figure never becomes a figure of "O."
     
  10. Jun 28, 2004 #9
    I don't understand this. You claim that for x dimensions, the number of immediate neighbors of a point is 2x. Please explain this.
     
  11. Jun 28, 2004 #10

    jcsd

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    There's no such ting as 'closest points' in space as there is always required to be one point inbetween any two points.

    If you are going for some sort of quanitiztion in which (3-D) space becomes a countable set of ordered triplets, it's actually quite easy to show that your scheme cannot as your space has a taxi-cab-like metric.

    We measure the distance between any two points in (Euclidean) space as:

    ds^2 = dx^2 + dy^2 + dz^2


    But in this system:

    ds = |dx| + |dy| + |dz| ==>

    ds^2 = dx^2 + dy^2 + dz^2 + (|2dydx| + |2dzdx| + |2dydz|)

    So for any measuremnt we made between two points there would be a noticeable difference between the distance given by the Euclidean metric and the distance given by the taxi-cab metric due to the triangle inequality (at whatever level the quantiztion took place).
     
  12. Jun 28, 2004 #11
    Using QM language, I would think of Dark energy as anti-gravitons. In other words, the destiny of a photon depends on converging vs. merging with other photons from other sources.
     
  13. Jun 29, 2004 #12
    Prometheus and jcsd,

    If the distance between two points approaches zero can be defined. The limit exists.

    [tex] lim_{d\rightarrow 0} f(d) \neq 0 [/tex]
     
  14. Jun 29, 2004 #13
    Prometheus,

    If we imagine a dimension as an infinitely extended line in both directions then each point on the line has two immediate neighbors.

    Two dimensions would have two infinitely extended lines intersect at a point and this point of origin would have 4 closest neighbors.

    Three dimensions would have three infinitely extended lines intersect at a point and this point of origin would have 6 closes neighbors.
     
  15. Jun 29, 2004 #14

    jcsd

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    Which function of d though?. As I said before there is always another point between any two points and your scheme assumes a taxi-cab metric.
     
  16. Jun 29, 2004 #15

    jcsd

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    I have already explained to you why this is not and cannot be the case. I mean fior a start ask yourself, how many different lines can intersect a point?
     
  17. Jun 29, 2004 #16
    I feel safe in coordinated systems, but the reality is, that dimension is very different then we have all assumed?

    Can you imagine everyones face when Reimann gave his speech and Gauss was sitting in the audience as a proud father?


    I hope I am not confusing the historical here, but if I am, can someone please correct.

    So indeed it got pretty mystical for a while, but we now understand not just the physics behind the search for dimensions , but of how "colorful," this search has been.
     
    Last edited: Jun 29, 2004
  18. Jun 29, 2004 #17
    The function of the metric (d) will not be always zero. When d=0, then space is continuous. In special relativity, when the spacetime interval is zero, this defined a constant velocity of light.

    In my research, when the metric and not the force is exactly zero, force and spacetime are equivalent.

    For nonorthogonal system, many lines (infinite) can intersect at a point. For mutually orthogonal lines, only three. Orthogonality is very important in my theory. In projective geometry, orthogonality is not preserved since distances are not preserved.
    In a sense, orthogonality predefines the meaning of distance or the geodesic (which can be curvelinear in other geometries).
     
  19. Jun 29, 2004 #18
    If we assume at the outset that the fundamental dimension of space is one dimensional then the search for the reality of higher dimension is now not necessary. But still we must not stop searching the mathematics behind the illusions of two, three and higher dimensions then after all the logical mathematical thinkings, we could come back to the realization that higher dimensions are merely the motion of lower dimensions. The motion of 0-dim creates 1-dim, motion of 1-dim creates 2-dim, motion of 2-dim creates 3-dim, motion of 3-dim creates 4-dim, etc. Once we talk of motion of something, we are entering the realm of physics. but the mathematics of motion is really the differential calculus invented by Newton mainly for the purpose of describing motion of the moons, the planets, the comets, etc. The existence of time derivative of a function. The subtle point to make is that the function was also depended on the space and the motion of space was never questioned except by del operator, [itex] \nabla[/itex]. But is this operator the motion of space? To me this operator is describing the change in size and shape of space and not its change in time.
     
    Last edited: Jun 29, 2004
  20. Jun 29, 2004 #19

    jcsd

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    Which function of which metric? you have to be clearer.

    I see, what you're getting at your talking about pseudo-Riemannian manifolds, or specifically Lorentzian manifolds. The numebr of events with an invariant interval of zero (e.g. events with a lightlike seperation) from a partciualr event is infinite.


    [quite]For nonorthogonal system, many lines (infinite) can intersect at a point. For mutually orthogonal lines, only three. Orthogonality is very important in my theory. In projective geometry, orthogonality is not preserved since distances are not preserved.
    In a sense, orthogonality predefines the meaning of distance or the geodesic (which can be curvelinear in other geometries).[/QUOTE]

    But as I said before you've go to be careful as it looks to me that your going for something simlair to the taxi-cab metric.
     
  21. Jun 29, 2004 #20
    Can we say that the change in size and shape of space can happen in no time at all? It is a fact that the change in size of space as depicted by the universal expansion can go beyond superluminal speed. This seems to indicated that change in space can be instantaneous. But both matter and energy can change only in time. But what about spacetime? Spacetime as what is implied in general relativity could only have a meaning if it is equivalent to a force. This equivalence happens at infinite curvature of spacetime which is really the quantum domain of the Planck scale.
     
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