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Why does Gravity occur?

  1. May 13, 2003 #1
    I finally broke down and looked at the the thread "Proof of the cause of Gravity" and thought that I might present a few ideas in that area myself.

    One of my philosophical remarks (perhaps one day I will tabulate them) is "There's a reason for everything, it just isn't always the one we want it to be". I don't think Gravity exists to hold our feet to the ground, or hold the atmosphere to our pleasant planet, though it does serve those functions admirably. I think Gravity exists to hold a certain quantity in Nature constant.

    In 1931 P.A.M. Dirac wrote a paper expounding on the fact that the quantities H, the Hubble Value, G, Newton's Constant, Ρ, the mean density of matter, and 1/T, the inverse age of the Universe were all approx. 10^−41 when expressed in Electron (or Proton) mass units. This is known as Dirac's Large Number hypothesis. A necessary implication is that these "contants" vary.

    An important model in Cosmology is the (somewhat misnamed) Big Bang Theory, the notion that the Universe started in a condensed state and expanded to it's current condition. Dirac's Hypothesis is consistent with it. More than a few authors have noted that Big Bang models are very sensitive to initial conditions, that small differences can lead to runaway expansion or immediate collapse. This is true even when we include the Dirac Hypothesis. However I refer to models which just combine the two as "naive models" for good reason, because they fail to take into account some very important and neccesary considerations. One is that all four of these quantiies must "track" approximately throughout the history of the Universe, and any initial mal-adjustment of conditions would cause them not to track. The naive models provided no mechanism to maintain such tracking.

    After many attempts to make the naive models work I realized that something else was neccessary. I worked with electronic equipment and was well aquainted with fed-back systems. I could not escape this simple conclusion:

    On the large scale the Universe acts as a fed-back system. And ordinary (Newtonian-Einsteinian) Gravity was part of the feedback mechanism.

    In a fed-back system there is generally an input quantity and the output "tracks" the input. If the input is a constant current or voltage the output may be a constant voltage, and it serve to regulate the output potential. In such a case the input is usually described as a reference quantity.

    Naturally we should want to know what the reference quantity is for our Universe. If we take G×T or H/Ρ we have a quantity with the approx. value of one in Dirac's units, with the dimensions of volume per unit mass per unit time, which represents the rate at which the Universe expands. R. Dicke has called this the Volumetric Rate of Expansion, and it seems to be the correct reference quantity.

    There are three implications in all of this:

    The Universe must operate on the large scale as a fed-back system.

    Gravitation needs more "parts" than 1/R^2 Gravity to maintain the proper rate of expansion.

    The third, not so easy to see, is that some of these mechanisms must operate faster than light. All these are neccesary to keep expansion or collapse at bay.

    It's well established that 1/R^2 gravity fails on the large scale, on the scale of galaxies by a factor of ten, of clusters of galaxies by a factor of a hundred, for clusters of clusters by a thousand. It would seem that the other parts of Gravity take over here. For our purposes Gravity is any interaction that maintains the proper rate of expansion.

    Your feedback is welcome.
    Last edited: Jun 6, 2003
  2. jcsd
  3. May 16, 2003 #2
    Why does gravity occur?

    For no other reason then that we observe apples falling to the ground, and planets orbiting the sun, and moons orbiting planets, according to the laws of gravity that have been discovered.

    There is no "why" question in Nature. Nature is what it is, we can only observe it and try to understand it.
  4. May 25, 2003 #3
    Well said - there is no why in nature. It just is.

    As far as saying gravity has anything to do with nature is wrong.

    Gravity is the distortion of space. Space is distorted by matter.
  5. May 25, 2003 #4
    If we can't draw logical connections

    between occurences in Nature, and say that this is so because this other fact is so, how would be able to have Physics. There are plenty of "whys" in Nature, and we use them all the time in Physics and in our everyday life too. Just look at all the deductions we can draw from the Principal of Relativity.

    The fact that we may not now or ever have some ultimate reason for everything does not in any way prevent us from drawing many practical and logical conclusions.
    Last edited: Jun 9, 2003
  6. May 25, 2003 #5
    Re: If we can't draw logical connections

    We have physics since we can measure and analyze the material world, and extract 'laws' that govern the way how matter behaves.
    The 'laws' describe relative truths about properties of matter, I assume there are no fundamental laws of nature, we just can find better ways of describing objective truth.
  7. Jun 10, 2003 #6
    Hi tyger - thought I would read your post on the LNH after responding on the other thread - I too am totally convinced that Dirac's intuition is entirely correct on the variation of the constants - in particular G - of course this destroys one of physics' sacred presumtions regarding Planck units - the dimensions arrived at by combining G, h and c. I am always amazes that so much of modern physics is devoted to extolling Planck units (which are based not on experiment, but rather cosmic numerology). Anyway - that is another subject -

    With regard to the issue of "why" gravity - its a perfectly logical question - when answered, it will put the goal post back further, and the ultimate question will change - there will always be "one more question" But to arrive at an explanation of why G has the value we measure - based upon some relationship to other physical phenomena, is a worthy pursuit. Einstein didn't answer the question of how mass warps spacetime - nor did he have any suggestions as to why G has its present value - GR is notoriously incomplete - to say that "it is just the way the world is made" is contrary to the spirit of science -What we seek in physics are relationships - we don't know what "charge" is, but we know that two like charges repel - we may never have a vocubulary to describe actuality - but we will find out what causes gravity in terms of other physical relationships (if we are allowed to ask the question).
  8. Jun 10, 2003 #7
    Yogi, I too noticed that GR was incomplete

    and failed to address those aspects, and that most cosmological theories had little if any experimental basis, and that is what drove me to that line of reasoning.

    At the grocery store a while back I saw a Sci. American that was titled "Brave New Cosmology" and I read the blurbs and thought "these guys are breathing down my neck, they've figured out some of the things I've found". Well when I got home and read it I was a little depressed because they had only sort of figured it out. They found that Gravity had to push as well as pull, they called it quintessence, but to me it's just another part of Gravity. And they said that there may be some kind of feedback, no, on the large scale the Universe acts as a fedback system, period. If they had started with the LNH they could have found all that by reasoning out the consequences the way I did twenty or thirty years ago.

    And there's still more that they haven't got yet. Like Gravity having "more parts" that don't go as R−2, parts that do everything from giving the galaxies their forms to holding the Universe together.

    BTW I don't believe there is any so called "Dark Matter", I think these other parts of Gravity account for all that Dark Matter is supposed to do and more.
    Last edited: Jun 10, 2003
  9. Jun 10, 2003 #8

    Because iT HOLD'S iT ALL TogetHer"...thats why.

    (What does it hold together?, Mass!)
  10. Jun 10, 2003 #9


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    Under General Relativity, Gravity is essentially the same thing as Spacetime (or a behavior of Spacetime). I suppose if gravity = spacetime, then you might as well ask "why does the universe exist?". If gravity = the behavior of spacetime, then I'm not sure we can answer the existential "why", but instead just try to understand its fundamental elements/holistic characteristics in order to make useful predictions about it.
  11. Jun 11, 2003 #10
    Yes - under GR there is a unification of spacetime with matter - and to my way of thinking this gives a clue to what we experience as the gravitational force - namely there is a holistic relationship between the universe and gravity - we could say as Parsons has (I believe I am quoting correctly) that it is the gravity due to mass that holds everything together - so gravity, cosmic mass, and spacetime are relatable - or we could say that matter slows down the expansion - and that gravity is related to the slowing effect of expansion (as per Freidmann's model of an expanding universe) and as advanced on one of the other topics on these forums (Proof of the cause of gravity)... or we could say as I have proposed that gravity is a consequence of expansion... or we could invoke the spatial inflow theory and do away with the notion of gravity as a force as does GR. The only theories that don't take into account the holistic nature of gravity are those based upon gravitons.

    Something worthy of consideration ... the dimensional units of the gravitational constant (cubic meters/per second squared/per kgm) that is, volumetric acceleration per unit mass. If we use a spherical model for spacetime of radius R that is distending at constant rate c (the velocity of light), we see that the volume of the universe is accelerating - this is simply a geometric relationship - having nothing to due with the 1a supernova data. Interestingly, if one carries out the calcs mathematically, you get a G value that conforms with its experimentally measured value ments (for a Hubble constant of 57). Moreover, the formulation is consistent with Diracs LNH in that G is shown to depend upon 1/R -- i.e., gravity decreases as the universe expands so the G force and the electric force are always ratioed at 10^42.
  12. Jun 12, 2003 #11
    Paerhaps a slight clarification, gravity arises from atoms, and those atoms bind into mass, and then the mass, (atoms) generate more gravity, to bind more mass.

    If it were not so, then the entire universe would be ruled by the two forces that are magnetism, and nothing would result, as none of it would bind itself into any kind/type/form of mass.
  13. Jun 19, 2003 #12
    If I'm not mistaken, mass is a manifestation of gravity, not the other way around.
  14. Jun 19, 2003 #13
    Try looking at it as, it is both ways, cause it is.

  15. Jun 19, 2003 #14
    I invented gravity! And the question mark...
  16. Jun 21, 2003 #15
    ......Yes! and no doubt, self deception too!

    (pardon my Humor, pleeeease?)
  17. Nov 2, 2003 #16
    Gravity and my theory

    Isn't the Mass of an object constant while its weight depends on the gravity applied to it?

    I have been reading a good deal about Gravity over the past weeks and have found that no one really knows how gravity works.

    The only thing that I have deduced so far is this.
    -The spinning of the earth (or any celestial body) most likely reduces the effect of gravity upon it.
    -Gravity is an unexplained occurrence that at itsf inner most core has a very strong pull force that reduces as you move further from it (much like metal to a magnet.

    I think that the main problem is that we have not encountered the primary point of attraction because this point is always surrounded by a mass of the materials that it has attracted. I believe that this could be a single atom (a Mass Magnet Atom) that is an everything magnet with incredible power. That would mean that there are one or many of these things at the center of all celestial bodies that have gravity.

    I will say that Mass Magnet Atoms (MMA's) exist; I think this would answer many of the holes in theories about gravity. Letfs also say that an MMA Gravity is a constant of G (Gravity). In addition I will also say that if you were to put to MMAfs together you would get something like this G2.
    On the other hand we could say that an MMAfs Gravity is the Variable G with an unknown property.

    This would lead to my point, if you were to put all of these MMAfs together you would, either way, wind up with this; G‡, absolute gravity which I think brings us to the Big Bang Theory with a modification. Imagine all of the MMAfs bound together with all matter in itfs primal form surrounding it and then Bang something sets it loose maybe the splitting of one of these MMAfs would cause an explosion unlike any other.

    If MMAfs exist then some questions would have to be answered
    -Is the gravitational force and Spin constant or does it deteriorate over time?
    - Do they attract or repel each other?

    I base this entire post on non scientific but rather what I have deduced from my own personal experience living with gravity.

  18. Nov 16, 2003 #17
    This is for all of you who dont believe?

    Subj: Post this on your website~
    Date: 11/16/03 4:01:05 PM Pacific Standard Time
    From: Amuzme36
    To: ghb@uwm.edu

    I cant believe a site such as yours? I have read your dis-beliefs about Jesus' Return...stating you all know nothing about the perpose of life? When you were born, and grew up with your parents nursing you, caring for you, loving you etc... did you really know that was your parent? Or were you just told and believed it from there on? Or maybe you need proof... DNA? Read the Bible? Try to understand its meaning, and what God has done for people in the early days of time... and why he sent a piece of himself down here on earth to be born into a man, named Jesus Christ to go through the trials and humiliation, torment, and betrail from whom he called a friend, Judas? Do you realize he died for you? For ME? For eveyone?? For your sins, and for the sins your going to committ? Not saying its ok to sin... cause its not... Just saying Ask Jesus into your heart and mean it and let him direct your path... no path is easy, and a narrow road is harder to stay on, than slipping off into every other direction other than??? You just have to know that we are all going to mess up,,, God knows that... Were human? But, we need to try our best to be like Christ... Ask Jesus to come into your heart and mean it, and than if you mess up, say your sorry and dont do it again... and than your truely forgiven... and from that moment on and it will take time but, ask God to show you the way and to help you understand the meaning of the word in the Bible.... and things will start making since...... Nothing good will enter Heavens Gates and stand in the presance of our Holy Father? NO ONE Evil in anyway? and what is on this web site is nothing good.. Yes I agree its hard to believe in something you dont see... but after you stop and think of how did we get here and why? LOL open your hearts and want to understand? Look out at the stars, the moon, sun, trees, birds.. YOURSELF IN A MIRROR>>> UH>>> who could make such a creation? IF NOT A GOD>>> and a GREAT GOD>>> Not the Evil one... He wants you to sin.. to think un-clear... Hes faught with God and always will..... Yes, some Christians wont make it to Heaven...Your right on that... because some arent doing whats right in the site of God.. But, thats not for us to judge.. Only God will and can judge his own creation.... You should NOT JUDGE THE JUDGE >>
    If you know what is right, and dont want to hurt someone, (AND YOU DONT) its a gift from God.. God is Only Love.... Nothing Bad.... I Pray for you all...

    Heres a Start: A: Admitt = Admitting you are a Sinner! (And dont be afraid to show it)
    Cause we all are!
    B: Believe = Believe in Jesus Christ, and believe he is Gods Son, and that he died for you and rose again.....

    C: Confess = Confess with your mouth, that you are a sinner and that you believe that Jesus Christ died for you, and that hes Gods Son, and that he rose again... (You must confess with your mouth, cause God wants us to tell it... it shows you believe it enough to tell it....( Shows God your willing to express your love for him Publicly) Means you ment it..........
    Jesus will return, in 2000 yrs.. If you knew anything about history, and the Bible at all,,,, maybe even scientist may of told you somewhere, but our Calendar isnt correct? No one really knows for sure even the true date of Jesus' Birth to even know for sure
    when to speculate when 2000 yrs are up for us? God isnt going to tell US when he will return, thats where trusting him comes invalved... Do really think that hes going to tell you? What are you thinking? I wouldnt tell my creation when Im coming back either? Why? So they can have a date and go? OH????? well, I still have this much time to goof off in life and sin... and then right before the time he returns, Than except Jesus? UH>>> WAKE UP>>>Use the brain God GAVE YOU! Open your eyes.... Someday your going to see.... I hope its not too late..

    You think about God, really and look deep into yourselves about what your saying about him and about the Bible... and do some asking for forgivness.....
    Watch a tv show called Jack Van Impe on sunday nites... and Sat... go to the www. site.. he will let you know whats going on in the world today... and no, we dont have alot of time left...

    Im a new christian, and A ferm believer in The Lord Jesus Christ I believe in good and evil... but, I want to be on the good side...


    One who is learning to walk in Faith
  19. Nov 16, 2003 #18
    Maybe you can find confirmation or some extra ideas in my idea about a multi-layered spacetime concept: https://www.physicsforums.com/showthread.php?s=&threadid=8203 ,
    post starting with: "Summary:
    Gravity is the first force, and all other forces are just emanations from this first.
    Our various 'realities' and 'dimensions' are restructured spacetime. Spacetime can be visualized as a giant totality of an unbreakable but almost infinite elastic membrane in constant movement (oscillating waves: the ripples of spacetime).
    Due a mechanism of 'pelastrations' the original membrane can create locally zones of multi-sheeted spacetime, called holons (cfr. quantum packages). They look like multi-layered tubes (cfr. Strings). ".

    Watch out ... these ideas may 'attract' you!
  20. Nov 27, 2003 #19
    gravity is caused by the fluctuationof space as the matter is moving. think of putting a few balls on a pillow the heaviest one sinks more and the lightest the least now just think of that in the complete thrree dimensions and think of the pillow as space and the weights of the balls to be the masses of cellestial bodies and that is gravity. The bend of space due to matter. :wink:
  21. Nov 27, 2003 #20
    So gravity is not LINKED to matter, right? First there must be matter ... and then that matter will cause gravity!
    This is totally illogic. That's like saying: the boats create the waves of the sea.

    My alternative: make in the middle of that pillow a large knot ... and see what happens then. That knot is your matter. The pillow is spacetime. Matter is just restructured spacetime in a unique combination.

    And: Sure boats create some local waves but not the essential ones.
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