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The paradox of Gravitation

  1. May 24, 2003 #1
    More years ago then I care to think about I discovered a contradiction in the way we think about Gravity. I called it the Paradox of Gravitation, and I decided that if it could be unraveled we could gain insight into the nature of Gravity.

    The paradox is this, people think of Gravity as being caused by a field, or space-time curvature produced by a gravitating body. To produce such a field, analogous to an electric field the gravitating body would have to "send something out" in the manner that an charged body sends out virtual photons. But what does a gravitating body do? It takes things in, it attracts other objects. So how can it produce such curvature or a field?

    And this is my resolution to the paradox, that every gravitating body simply swallows up the space around it, and anything in that space. There is no "field", and any curvature is an accidental result of the "swallowing up" process.
  2. jcsd
  3. May 24, 2003 #2
    It's pretty simple

    to write the equations for the "swallowing up process", anyone with moderate math skills can do them on the back of an envelope. Just as they can for many other ideas. It's the concept that is important.

    There are too many papers now with ten pages of equations in search of an idea. What is needed in Astrophysics is some original thinking. There is a large and growing body of experimental data in need of interpretation, instead people work on purely abstract theories with little if any experimental support. It's the "fashionable" thing to do, I suppose. Yet I can't think of any major developement in theory that wasn't achieved by staying close to the experimental picture. Nor can I think of any that didn't involve some new insight, which meant that someone had to throw out or modify the old view.

    My personal view is that Astrophysics is the next growth area, if only because Particle Physics has run the experimental gamut. There are many things on the Astropysical scale which are inexplicable by today's theories but they will require "Feynman like imaginations" to solve them, and I haven't seen any in action yet.
  4. May 24, 2003 #3


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    Re: It's pretty simple

    Oh it's easy? Well, then perhaps you should do it for us.
    Physicists do not deal in concepts -- they deal in the quantitative explanation of experiments. You'll never meet a physicist -- not a single one -- who will tell you that concepts are more important than rigorous models. It's simply your (apparently uneducated) opinion.
    In.... astrophysics? Astrophysics, like particle physics, is actually one of the more grounded areas of physical research. Perhaps you're using the word 'astrophysics,' when you really mean cosmology. I can't remember the last time anyone accused the astrophysicists of being too abstract! Maybe you just don't know any astrophysicists.....
    Yes, that seals it -- you really don't know a single astrophysicist.
    How about, oh, relativity... or gauge theory...
    Of course one must modify an old idea to make progress. This seems like a trivial statement to me.
    In fact, the number of experiments needed in HEP grows faster than the number of planned machines to perform those experiments. You really seem to have no connection to reality.
    Oh? Which things are these? And are you attempting to characterize Feynman as a man who dealt in 'concepts,' not mathematically sound theory?

    - Warren
  5. May 24, 2003 #4
    Chroot's welcome to his opinion.

    And yes I did write the equations on the back of an envelope, but concepts are still important, even Feynman said that.

    Something that is inexplicable by todays's theories, how about the rings of sn1987a, and did you know that the Puppis-α remnant, which is several thousand years old has rings? So the rings won't be destroyed by the blast wave after all. Sorry guys, wrong theory! Bad concepts.

    Yes, there are fashions in Physics and many follow them.

    Einstein knew a lot about experimental evidence, he was a patent clerk by trade.

    As for gauge theory, the concept was invented by Hermann Weyl who was a pure theorist trying to develope a combined model of gravity and electromagnetism.

    The HEP experiments planned are taking longer and longer, the LEP experiment for the Higgs would have taken a year and that is why the LEP director canceled it. And taxpayers aren't as willing to shell out big bucks for equipment now.

    You forgot to comment about the ten pages of equations in search of an idea.

    It may seem trivial to you that people have to modify their thinking but it sure seems difficult for a lot of people.
  6. May 27, 2003 #5
    Here is a link to another weird physics theory, called "Space genetics" by some russian physiscts (Dr. Dark Energy), who also has a theory in which mass "consumes" space, and radiation by stars "creates" back the space consumed by mass...

    Space Genetics.
  7. Jun 3, 2003 #6
    Tyger - your concept of spatial inflow leads to empirical results consistent with GR - there are a number of well reasoned articles on the net based upon the idea that matter consumes space - the first time I encounted this notion was in Ted Harrisons text book "Cosmology" in connection with black holes - the idea being that space flows in toward black holes at a speed c at the event horizon ergo, light cannot escape since it cannot travel upstream at greater than c. Tom Martin has developed the mathematical theory for a number of experiments that can be used to distinguish between the spatial inflow theory and GR.
  8. Jun 3, 2003 #7


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    Yogi--you say there are a number of well-reasoned articles on the net based on spatial inflow ideas. Please give some links for those, like myself, who might be curious to know more.

    Tyger--one of the PF metors, Damgo, presented a picture of a black hole event horizon which is similar to the spatial inflow
    picture. This was in the thread "Black holes and singularities"
    and he said it was as if the event horizon was rushing at you at speed c. You couldnt get away because, as we know from the Minkowski space of SR, you can not go faster than c. This seems at least superficially similar to the idea that space is flowing into the black hole and is flowing at speed c as it crosses the EH.

    I cannot comment because I'm not sure I see how the model would work, but if you have some equations for a spatial inflow model that reproduce GR effects then you could email them to the authors of the the articles on the internet which yogi talks about. If there is a body of spatial inflow literature on the internet, it is an automatic audience of people to review and respond to your equations.

    Yogi--Personally I cannot picture it, but you say spatial inflow "leads to empirical results consistent with GR". Are there empirical results, such as light-bending, which are exactly duplicated? Would be interesting to see this discussed by knowledgeable people.
  9. Jun 3, 2003 #8
  10. Jun 3, 2003 #9


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    [moderator hat]
    note: I've deleted all the chroot-logicalatheist argument drek from this topic. Maybe the discussion can be salvaged now.

    I'm also moving this to the T.D. forum.
    [/mod hat]
  11. Jun 3, 2003 #10
    hi marcus - The most analytical approach to the subject of spatial inflow that I have come across are the articles by Tom Martin ...
    martin@gravityresearch.org cited above

    There are also a number of qualitative approaches put forth in connection with ether theories - e.g. Caroline Thompson and others

    Martin has conducted a number of experiments on hollow spheres (Cavendish type measurements) to attempt to detect differences that would occur between GR and the spatial inflow theory. He has also proposed some experiments that would validate or invalidate the spatial flow theory based upon the difference in time dilation that will occur at the sadle point of zero gravity between the earth and Sun.


  12. Jun 5, 2003 #11
    Instead of using the term "gravitating body", why not use the term "false vacumn"? Or, gravitation is the false vacumn trying to swallow up stuff outside it and return it to the false vacumn. That is, the Universe originated there (??where it belongs??)and the false vacumn is just trying to return it.

    That makes it (IMO) not necessary for us to formulate any particles, like gravitons, for gravitation to work. And so Einstein's description can remain geometrical and is easier to reconcile to quantum mechanics -- i.e., it is a description of happenings above the Planck length. There would still be quantum action in gravity, in that only discrete bits of stuff could return to the false vacumn. Singularities would also be out, and not needed to be worried about -- they would just be a consequence of trying to use GR in an area that it lost any meaning, or predictive power.

    It would make it to where we didn't have to find a cause of gravity in a relative Universe. I can't fathom what inertia would be then, I mean, how a cause for it could be connected to this.

    I think it was the poster "marcus" that has a topic about what has happened to the energy of the CMBR as it has cooled down over time. I've read articles that indicate it has been converted to gravitational potential energy. Why not believe that energy has been returned to the false vacumn VIA this description? To me that should mean though that there is no quantum of action in returning stuff to the false vacumn.

    Just my musings ... I'm sure there are all kinds of holes in it.
  13. Jun 5, 2003 #12
    Probably the best and simplest responce I can tell you is from line spectrography.

    The spectral absorption lines that are observed, and used to adjudicate Doppler shift of light, PROVE conclusivly that matter absorbs EMS, and the next simple step is to find the place in the universe that has NO EMR, well, it is the inside of the event horizon of a Black Hole. (The rest of the universe is FULL of EMR)

    Matter absorbs EMR, space is full of EMR, gravity is simply the absorption of EMR, at low wavelength levels, long low wavelength levels.

    From there you need to figure out what the planet does with the Absorbed EMR (after all, the planet is made up of the same kind of stuff, atoms, and we KNOW they absorb EMR) which would be to bring it to it's center, wave shift it, and re-emit it as heat.

    It is pretty simple, just to get some people to believe it, OYE!
  14. Jun 5, 2003 #13


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    The correct explanation of this is unfortunately not intuitive because of it's quantum theoretic origin. Briefly, elementary particles are classified in terms of spin, mass and charge, and only massless even-spin particles can mediate attractive forces between like charged bodies: suffice it to say that gravitons are spin-2 and, like photons (which are spin-1, consistent with electromagnetic repulsion between like charged bodies), are massless.
  15. Jun 5, 2003 #14
    Re: Re: The paradox of Gravitation

    The only problem with this picture is that Gravity doesn't act between two bodies the way that other forces do. It acts on the space around a massive body. So the picture of the spin-2 graviton may not even apply in Nature. I think we're still looking for a competent quantum theory of Gravity and it would be unwise to close our minds to any viable possibilities.
  16. Jun 6, 2003 #15


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    Re: Re: Re: The paradox of Gravitation

    First you need a mind open enough to want to understand the current state of theory and be honest about how it reflects on your own ideas.

    Full QG isn't needed to understand gravity's behaviour at lower energies where GR, and hence it's linearization describing a self-interacting massless spin-2 field - the graviton- applies. This means that whatever gravity's true nature, the graviton will remain an indispensible concept.

    More generally, the modern concept of particle itself holds up only as a group theoretic approximation: Briefly, particles are defined in terms of their mass and spin which label - and this is their real significance - the representations of the poincare group under which their states must transform to preserve invariances related to the local geometry of spacetime. However, it is only in minkowski space that poincare symmetry holds globally. Since curved spacetimes are only locally flat, the particle concept only holds as an approximation in regions over which curvature varies sufficiently slowly.

    Let me describe in schematic terms how the gravitational field is viewed in terms of spacetime curvature and it's relation to the particle viewpoint at lower energies where GR holds.

    Begin by representing the connection between spacetime curvature and energy density in general relativity schematically by the relation

    (spacetime curvature) = G x (mass-energy density)

    where G is the gravitational constant which thus characterizes how much spacetime curvature would be created in the presence of some given mass-energy density. We can understand why mass-energy density, rather than just mass-energy, appears in the above relation by noting the basic inverse square law (curvature has units of inverse distance squared) behaviour of gravitational force it implies, and then observing that if a planet's density were increased by gradually shrinking it, it's inhabitants would feel themselves growing heavier as they approached the planet's centre of mass.

    Can this be taken further to build a more operational view of gravity? No, not directly, because quantum theory is needed to understand the current picture of fundamental interactions. But the main idea - and I think you've seen this before - can be understood by observing that two people on roller skates throwing a ball back and forth will roll away from each other (as a result of momentum conservation). Somewhat similarly, electrons are mutually repelled as a result of exchanging photons, and likewise, gravity is the result of graviton exchange.

    However - as you already know - the analogy doesn't work as well in this latter case because gravity is attractive, the explanation of which is - as I mentioned - not intuitive because of it's quantum theoretic origin. Repeating it, elementary particles are classified in terms of spin, mass and charge, and only massless even-spin particles can mediate long-range attractive forces between like charged bodies: suffice it to say that gravitons are spin-2 and, like photons (which are spin-1, consistent with electromagnetic repulsion between like charged bodies), are massless (Actually, since theories with bosonic gauge fields like EM and GR exist as classical theories, this can be seen from looking at the interaction potentials in the corresponding classical lagrangians, it's just that spin itself is a purely quantum theoretic concept which confuses this intuitive classical aspect of the picture).

    The reason that gravitational and electromagnetic fields - whose quanta as you know are the graviton and photon respectively - grow stronger as their sources are approached is also quantum theoretic. Again, briefly, because of the time-energy uncertainty principle, the distance from a source that field quanta can travel decreases with their energy. So, for example, the strength of the gravitational field grows stronger as a gravitating body - like a planet say - is approached because gravitons of progressively higher energies are encountered (analogous statements hold for the electromagnetic field).

    So what's the connection between the classical notion of spacetime curvature, and the quantum view of the gravitational field as a continuum of gravitons? The answer is that because gravitons - unlike photons - interact with each other, they assemble themselves in a way that's in fact governed at lower energies by general relativity, so spacetime curvature is merely a large-scale structural quality of the resulting gravitational matrix.

    Although this picture must - as you know - break down at very high energies, it provides no real foundation for your view of gravitational attraction as paradox.
    Last edited: Jun 9, 2003
  17. Jun 6, 2003 #16
    steinitz, I have another post

    on the board called "Why does Gravity occur?" which better states my views on the subject. Something I've always (since I can remember) disliked about GR and many of it's offshoots is the arbitrary way in which certain elements are introduced. As you can see by the post I've tried to eliminate the arbitrariness and bring all the elements together into a single picture.
  18. Jun 6, 2003 #17
    Most attempts to explain forces that are communicated through space are based entirely upon conjecture - no one has ever seen a virtual photon and by definition - never will - nor will they see a graviton - these are at present useful metaphores - for some types of calculations - but more likely not representative of reality - the notion of spatial inflow and the false vacuum analogy are to my way of thinking more likely to lead to a true picture of gravity - modern physics depends upon many ad hoc insertions to get the desired results
  19. Jun 7, 2003 #18
    Spatial Inflow?

    Ok, I have heard on a number of accounts that throughout the universe matter is coalescing. If this were true and if your statement that matter is consuming space were also true, then would not the increasing densities of matter necessitate the shrinking of space--and thereby not explain the fact that the universe is expanding?

    Perhaps inflow of matter creates an outflow of space...could this not bring about proportional degrees of pressure and cause further inflow of matter?

    On the level of the universe, if there were a very large black hole in the center...the inflow of matter would result in a converse outflow of space, in which the whole of our galaxies reside--and in which other matter is also coalescing...

    Keep in mind that I don't understand why there should be differences in pressure, or if there is such a phenomenon, what sort of pressure exists. Plus, I'm using the term pressure very loosely. I'm just trying to make sense of something that seems very counter-intuitive, the facts of which elude me since I'm not experienced in the complexities of mathematics required for a firm understanding.
  20. Jun 7, 2003 #19
    It is not inconsistent to have expansion on a cosmic scale and have space being absorbed on a local scale - one consequence of this model would be a false vacuum - that is, a universe under tension rather than pressure - my personal bias is that the universe is in a state of nagative pressure (false vacuum) and as it expands it creates energy just as does a spring when it is stretched - so energy is being generated at a rate that exactly counterbalances the loss of negative potential energy i.e., the totality of energy is always zero - this satisfies a lot of physical-philosphical problems in that we don't need an outside force (creator) to explain its origin. Along the same line - we don't have to hypothesize that space is falling into matter (black holes) ... rather we can consider that matter is acted upon in all directions as an inertial impediment to the isoptropic expansion - this creates a gradient that appears as a spatial inflow - but there need be no real influx -
  21. Jun 8, 2003 #20


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    Then how do you, tyger, interpret the existence of curved space vacuum solutions of einstein's gravitational field equations?
    Last edited: Jun 8, 2003
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