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What is dark energy?

  1. Sep 11, 2003 #1


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    what is dark energy? i think that when dark energy was discovered
    science didnt know how profound the discovery was.
    i think that dark energy is the primal source of everything,
    i imagine an instability in the dark energy built to such
    an extent that it could no longer be contained, this eruption
    of energy formed our univers.
    this eruption "not a bang",more of a "phut",is what we perseve
    as the expanding metric.
    the CBR is the outer boundery of the "rift" in the dark energy
    as entropy has been disturbed by this perturbance the particulate
    matter will eventually be reabsorbed into the dark energy to
    correct the ballance.
    please tell me why im wrong.
    Last edited by a moderator: Feb 5, 2013
  2. jcsd
  3. Sep 11, 2003 #2


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    Re: theory

    I suppose anyone who takes cosmology seriously will feel the poetry of it from time to time. And although the professionals
    disappoint us by raising more questions than they answer---in fact by answering very little----a person will want to look ahead of firm knowledge and imagine what a solution might look like----to dream of a possible final version of the story. That is poetry and it is not bad---there is room for poetry.

    But at this point our knowledge is pathetic and even though the professional cosmologists actually AGREE at least temporarily on a basic picture of the makeup of the universe (flat, 70 percent dark energy, 25 percent dark matter, 4 percent the kind of matter we can see and more or less understand)

    They could be wrong.

    And even if they are right, what they agree on is only another name for an immense ignorance----because what is this 25 percent that is "dark matter"? and (as you say) what is this 70 percent "dark energy"?

    Each one of us has the freedom to completely disbelieve the picture of the universe presented by contemporary cosmology and to formulate, if we choose, our own worldview.

    (Personally I love the cosmologist's consensus view and am very happy with all the possibilities it offers and chances for future discovery! But ultimately each person is responsible for his own view. Personally I advise patience. Dont try to rush it. Trust them to come up with something even weirder next year!!! This is a good historical period for just waiting to see what the new satellite instruments find next.)

    And by the way, tho I am skeptical of every cosmic system it seems to me that yours----that goes "phut"----is no more unlikely than the rest. You are almost certainly right that when they found a dark energy term in the equation they didn't have the foggiest what they were taking on board. Whatever it is could indeed have participated in the very earliest inflationary era (if there was one) prior to Everything We Know.
  4. Sep 11, 2003 #3


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    MARCUS i "love", your double edged sword,but i asked for disproval
    you say "wait for for new discoveries," i say every new discovery
    brings about umpteen new theories, can you or anyone prove my
    theory wrong?
  5. Sep 11, 2003 #4


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    how do I disprove a poem?
    do I even want to disprove a poem?

    we do not know the story of creation, you do not know
    and charley lineweaver does not
    and ned wright does not
    and I do not
    skepticism and agnoticism and a kind of sober wonderment
    are all we have with which to face the big blank page
    the story of creation has not been written

    even though all the recognized authorities appear to agree
    that there is something called dark energy and it is
    73 percent of the average energy density in the universe
    yet it might not exist and they might be wrong
    ultimately the story of creation each tribe and civilization tells its children is just that: a story.

    I like yours: we emerged from the dark energy and in time we will be re-absorbed into it. I find some comfort, even, in that story.
    I will not try to disprove it even though you ask. Let someone else disprove it
  6. Sep 11, 2003 #5


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    Wolram, it suddenly dawned on me------you may be asking for someone to derive a testable prediction from your theory.

    You want someone to transform it into a scientific theory-----the kind of thing that makes predictions and that can be falsified (proven false by observation).

    A scientific theory is something that can be falsified. If it cant be falsified it is scientifically meaningless.

    If it passes all the tests we come up with, so much the better, but it cant be so mooshy and amorphous that it makes no definite testable predictions at all.

    right now I cant think of any way to test your theory----dont see anything it predicts that I could measure or check against it.

    so I tend to think of it as a creation story

    but now I see that is not what you want at all, you want it made into a testable scientific theory.

    dont you have any respect for the human imagination?:wink:

    be happy with it as a creation story, that is worth something,
    while scientific theories are tuppance a dozen and only cause trouble.
  7. Sep 11, 2003 #6
    Dark Energy

    I am not so sure about disproving you, for you might be on to something. Maybe the energy, which can be mathematically broken up into components of momentum, and Planck's constant, can be shown to be an intrinsic part of a vacuum based on a mathematical law of consistency. Consider a space that is infinitely dividable, e.i. a perfect vacuum. For simplicity's sake, let us suppose, for a moment, that we are speaking of an infinite Euclidean 3-space that forms a sphere. One can construct a lattice out of an infinite number of parallel x, y, and z axis through every possible orientation of the sphere. Geometrically, this creates a multi-sphere where the intersection of all points in the lattice form centers of an infinite number of spheres formed by the lattice structure. There are an infinite number of infinitely close parallel lines in the lattice that represent a slopes of a given infinite number of spheres. Now we assume that the parallel lines extend to both negative infinity, and positive infinity. This forms an infinite universe that is similar to perceived universe of the late 1800's(Of course we know this does not describe our universe, but the mathematical conclusion I will be representing here applies both to a finite Universe of curve space, as well as to a Euclidean universe. So it doesn't matter, in this case.).

    In this universe, there are an infinite number of parallel spheres along all the given axis, which form a cube like structure. Let the three dimensions composing a sphere Q be represented by x, y and z, and the dimensions composing a sphere R be X, Y, and Z. You can draw a straight ray from the center of a given sphere Q through the North pole of another sphere R(assume that the x line that runs through the center of sphere R also runs through the center of sphere Q, so that spheres R and Q are parallel.) The angle between this ray and the x axis that runs through the center of spheres Q and R is between 0 degrees and 90 degrees depending on how far sphere R is away from sphere Q along the x axis. The actual equation that describes the distance from the North Pole of sphere is
    sec^2(theta) d(theta)dt. Where (theta) is the angle between the ray that runs from the center of sphere Q through the North Pole of sphere R and the y axis of sphere Q. Now suppose that theta approaches 90 degrees, then the distance between the North Poles of both spheres along the x' axis approaches infinity. Now, suppose that the angle theta continues to rotate on through 180 degrees, then the distance between both spheres along x' goes to zero, and yet x' remains positive on both sides of y because second is squared. If one looks at a graph representing this based on the equation, one will quickly ascertain that the graph of the X, Y, and Z axis of sphere R is reflected when theta is between 90 degrees, and 180 degrees, so that although sphere R's position along the x' axis continues to remain positive, it is traveling, in the opposite direction toward sphere Q. So we know that the distance from the North Pole of sphere Q and R, is always on the positive side of the the x' axis. Now suppose that sphere Q, and R remain separated from each other along the x' axis by an infinite distance, The angle between the sphere Q and Sphere R is 90 degrees, while the angle between sphere R and Q is 270 degrees, or 90 degrees counter-rotation. Let both spheres be rotating clock-wise on their z axes at the same angular velocity. One can draw an infinite number of rays from Q's center to every point on the x' axis from 0 to positive infinity which corresponds all possible angles of rotation of sphere Q can take between 0 and 90 degrees. Likewise One can draw an infinite number of rays from R's center to every point on the x' axis from positive infinity to a finite number which corresponds all possible angles of counter-rotation that sphere R can take between 360 degrees and 270 degrees, or between 0 and 90 degrees counter-rotation. Now the angle between sphere R's Y axis, and all points on the x' axis that are within a finite distance of sphere Q, is 270degree, or 90 degrees counter rotation. Inversely, the angle between sphere Q's y axis, and all points on the x' axis that are within a finite distance of sphere R, is 90 degrees, or 90 degrees rotation. Therefore, as sphere Q rotates from 0 to 91 degrees, a point p on x' goes from zero through positive infinity, and arrives at a coordinate that is within a finite distance of sphere R. But if point p is within a finite distance of sphere R, then the counter-angle between sphere R's Y axis and point p on x' must no longer be 90 degrees, but must be less then 90 degrees counter rotation. If sphere R is rigid, then that means that sphere R must have rotated by some given amount N. Well if sphere R rotated by a given amount N, then some point q that was some finite distance L away from sphere R on x' goes from L through positive infinity, and arrives at a coordinate that is within a finite distance of sphere Q. But if point q is within a finite distance of sphere Q, then the angle between sphere Q's y axis and point q on x' must no longer be 90 degrees, but must be less then 90 degrees rotation. If sphere Q is rigid, then that means that sphere Q must have rotated by some given amount M. So the rotation of spheres Q and R perpetuate each other if spheres Q and R exist within an infinitely dividable space, or a continuum. Furthermore, spheres Q and R must rotate, according to the math, if any finite angle can be measured on either spheres. This could account for the dynamics a vacuum. If one works out the equations, one will find that either clockwise or counterclockwise of the spheres will account for the position p and q on the x' axis. Therefore the change in position of p, and q with respect to x' is a scalar, the sum of two opposite possible rotations which reduces the change of p and q with respect to x' to a vibration. Let p be a given particle m1, and E the kinetic energy of particle m1 in one direction of particle m1's vibration. Then the energy of in 1 direction would be m1 would 1/2mv where m is the momentum of m1, and v is the velocity of particle m1 in one direction of it's vibration. Suppose that the motion of m1 creates a ripple within the fabric of the continuum, then this ripple will expand out at right angles to the motion of m1, and will have the total energy equal to that of m1 in one direction of m1's vibration, and is = to 1/2mv. In quantum physics, let m be Planck's constant h existing as the result of this mathematics describing the intrinsic dynamics of a vacuum. A similar argument can be formulated for non-Euclidean geometry, accept, in non-Euclidean geometry, spheres Q and R don't have to be an infinite distance from each other for there angles with respect to x' to be zero! This means that the dynamics of a vacuum of curved space can be mutually perpetuated by spheres within finite distances of each other.

    What do you think? Does this prove or disprove your hypothesis?


    Last edited: Sep 11, 2003
  8. Sep 12, 2003 #7


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    as usual i could be wrong but, if the speed of light is constant
    in the vacuum, then the permeability and permittivity must stay
    constant, how is that possible if the metric is expanding?
    the only way this can be so is that these properties exsisted
    befor expantion.
  9. Sep 12, 2003 #8


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    Wolram, compliments on this question.
    I think it is about writing maxwell's equation describing the propagation of electromagnetic waves----but writing them in
    a space which is expanding ever so gradually, instead of remaining static

    Unless I am missing something this question might appropriately start a thread on its own. I dont see it having any hard-and-fast connection to your universe-picture, or my responses, or to Edwin's discussion (which I have not yet had time to read in detail).

    In the prevailing model of space that cosmologists use, the speed of light is locally constant.

    There are no global coordinates in GR, only local coordinates. So one can study the propagation of light in local coordinates----in a particular locale around some particular time.

    The expansion of space is so gradual that it does not make any perceptible or practical difference to local physics.

    And the equations that govern wave-propagation are local affairs
    relating what happens only a few feet and a few nanoseconds away.

    Locally, the world described by GR looks like the world of SR (special or flat, unexpanding relativity) and hardly diffeerent from the world of Maxwell or Newton or Euclid.

    The trouble comes when you look at light traveling very long distances

    In a period of one billion years, light may actually cover a distance which, at the present moment, measures MORE than a billion lightyears. And because of the slow insidious stretching out of space, it also arrive with its wavelengths a bit stretched.

    So in GR the speed of light, although it is *locally* constant, is not a constant globally or long range or at large scale. To emphasize the paradox, we are currently receiving light, in fact, which was emitted by objects which were receding from us at faster than c when they emitted the light and which continue to recede faster than c up to this very day. How can that poor light have ever have managed to reach us? But it did and is being observed right now----light from any quasar with redshift greater than 3 for example. Lineweaver has some good diagrams of this.

    I suppose one can think of this as a correction to Maxwell's equations that is just too tiny to put into the equation. But each time the light goes thru one cycle of undulation it is effected by expansion by this unmeasurably small amount and after a billion years of travel and quadrillions of undulations the combined effect adds up to something.

    "as usual" we could all be wrong, as your post reminds me

    does this explanation help at all?
    Last edited: Sep 12, 2003
  10. Sep 12, 2003 #9


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    IIRC the speed of light in Maxwell is the ratio of the two quantities. So they could both change - double, say - while the ratio stays constant.
  11. Sep 12, 2003 #10


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    This raises an interesting prospect, even a bit difficult to contemplate

    ε0 is nailed down by the fine structure constant (unless things like planck's constant, electron charge, local speed of light in vacuum, i.e. c, are supposed to double or get reduced by half etc., or unless the fine structure constant is supposed to change radically)

    α = e2/4piε0hbar c

    Cant change epsilon naught (in local space) radically without changing 1/137, or hbar, or c. With stunning effects on the way things look locally.

    Not sure what it would mean to change epsilon and mu naught in some global way---as opposed to locally. If you can clarify or be more concrete I would be interested to think about what this could mean.

    I tend to imagine light traveling its usual speed in the surrounding space, with its usual epsilon and mu naught, and then later because of the overall geometry we see that it has covered some unexpectedly large distance (because the space it already traveled thru then subsequently stretched out and suchlike global considerations) so that the day-to-day microscopic life of the light in the local space it happens to be in is really rather unremarkable.
  12. Sep 12, 2003 #11


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    And, IIRC, μ0 is a geometric constant, not an empirical constant, so it can't change at all.
  13. Sep 12, 2003 #12


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    thanks MARCUS,
    my origonal thought was if c is constant in the vacuum
    then the two Ps should also be constant, but that dosent
    work if space is expanding, the two Ps should be getting
    then i thought that if the two Ps were in existence
    as a part of a "scafold", befor expantion then everything would be
    all neat and cosy again, hence my theory.
    must go my mercury is boiling.
  14. Sep 12, 2003 #13
    Last time I tried get discussion on these matters, I was murdered by Occams razor. I tried to understand, would we really notice stunning effects locally? Or would changes be so drastic, that everything we know would change along, leaving us blissfully detecting all being as if the same. And only in relation to some other 'local space' could we determine something funny is going on. 'local spaces' might be separated by nanometers or billions of lightyears.
  15. Sep 12, 2003 #14


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    many thanks to EDWIN,
    i am sorry that i can not follow your formulation, my
    education finished when i was 15.
    i can visulise part of your theory but that dont
    excuse my ignorance.
  16. Sep 12, 2003 #15


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    at first sight, at least, your questions seem to hard for me to reply to so I must pass and let some more confident individual have a go at them

    BTW did you ever take a look at an introductory textbook
    about differential geometry----it would help me explain what I mean by local and global

    it is a very plain unglamorous business----like the earth has an atlas of flat maps that approximately fit it, locale by locale, but it has no global worldwide flat map

    well the universe is NOT shaped like a sphere in any sense as far as we know, but it is analogous in the sense that there is not
    one global system of coordinates (as far as we know)
    but there are coordinate patches that work pretty well that apply
    to pretty decent approximation to limited regions of space and intervals of time

    this is vintage 1915 stuff
    there is nothing jazzy about it

    Andrei Linde for example is talking about other universes with other lists of fundamental constants and laws of physics----vintage 1990 stuff and very different.

    We expect fundamental contants to be the same all over the earth even tho there is no global flat map----it is a familiar routine thing---and we expect the constants and laws to be the same all over the observable universe even tho IT does not have a global set of coordinates.

    Linde and others are talking about places way beyond the observable universe realm where the physical laws and constants are even radically different (not just by a fraction of a percent or something, like people talk about in our own universe) so it is kind of "here be dragons!"---a bit mythical but one never knows.

    Of course you realize the hidden agenda in all of cosmology is to stretch human credulousness to the very limit:wink:
  17. Sep 12, 2003 #16

    I found the following website yesterday, and it has some very interesting findings regarding the theories being discussed here. These findings should clear up some of the questions regarding the variability of the speed of light c in a vaccuum, and the Maxwell's equations. These findings were uncovered by experimental devices as detailed in the paper on the website. Happy Reading!



  18. Sep 13, 2003 #17


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    thanks EDWIN,
    if only part of what he is saying is correct, our
    preasent day view of almost everything is wrong.
    some would say parts are crackpot, but im not sure.
  19. Sep 13, 2003 #18


    You know what they say about genious: There's a fine line between genious and insanity. I personally think that line happens to be success. But who know's? Ha, ha.


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