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Thread: What is Gravity

  1. #1 What is Gravity 
    Forum Professor Zwolver's Avatar
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    I know.. it's a huge mass attracting another mass, but can we block or simulate it in space?

    And what particles are causing gravity. Nutrino's, positrons, or even minor ultrahigh frequency light?

    Thanks anyway.. hope there is an answer.


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  3. #2  
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    Gravity depends on mass and/or force applied to that mass. For example if you apply a force to some object and accelerate it, it'll feel more gravity (gravity is also known as acceleration). If you get away enough from any mass (i.e. outer space) you'll feel very small gravity.

    As far as I know, we are far away from being able to manipulate gravity in any controllable way.

    Gravity is caused by hypothetical particles called gravitons (it isn't a real particle because it can't be detected). This particle was invented to explain and represent gravity in a standard model.


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    I did read a story once about simulating a huge mass by indeed rotating a small mass so fast that it generates a mattermagnetic field (or some kind of).

    Nobody is testing it yet.. but it might be that if a force can't get it's energy out by more kenetic or heat energy, it has to find another way to lose it's energy (by gravitons as you call it)

    but i hoped there was more known about it.
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    Isn't the existence of Gravitons in doubt? I mean, is gravity not an inherent characteristic of the universe? It is in-built into the fabric of space-time itself and is based purely on other energies such as electromagnetism. So why does there need to be particles such as Gravitons?
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  6. #5  
    Universal Mind John Galt's Avatar
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    I believe the majority of physicists accept the reality of gravitons, even though they have never been detected. There are alternative explanations available that are consistent with general theory. Perhaps MItchell can comment more eruditely.
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    ...But everything is electrical in nature and gravity is just a way to describe the normal attraction of one thing to another due to unlike charges. Is this not the case?


    Could someone explain what the hypothesised Graviton does?
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  8. #7  
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    No. There are four fundamental forces, and only four, known to exist in the Universe:

    The electomagnetic force, mediated by the photon
    The strong force, mediated by the gluon
    The weak force, mediated by W and Z bosons
    The gravitational force, thought to be mediated by the graviton. Gravity, as far as we know, is uni-polar, unlike the electromagnetic .

    In order for particles to influence each other particles from one must interact with another. The exchange of gravitons is postulated to explain the gravitational influence of one body on another. It has nothing to do with electric charge.
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    I read briefly about these four fundamental forces but they haven't even detected Gravitons - It's all hypothesis.


    I still cannot understand why Gravitons must exist: They are surely just something that are inherent to the universe. ie, Gravity is not caused by particles called Gravitons. rather, Gravity exists because of the actual structure of the universe.


    I do not mean to anger you my friend. I am trying to do what every other scientist does - Learn about the world around us.
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  10. #9  
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    I think no one knows what gravity is. We can create an exact equivalent by accelerating a lift in space. There is no known difference between being accellerated and standing in a gravity field. I think an objective view would simply say... gravity is accelleration. And then might ask the question "how are we being accellerated continually" and "is there a connection with the continual accellerated expansion of the universe".
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    Even though Isaac Newton formulated laws that gravity seemed to follow, it was only a discovery and it remains to be one of the many fundamental forces of nature. The hypothesis of the existence of gravitons is meant to be understood in the standard model. In fact, in Stephen Hawking's Brief History of Time, Hawking says that after Einstein's Theory of Relativity was published, it didn't seem to explain the concept of gravity. Einstein then modified it to give the General ToR.
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  12. #11  
    Forum Professor Zwolver's Avatar
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    what is this for a theory then

    If gravity is a constant stream of particles that bump onto molecules but don't have enough energy to change them. Then they are heading somewhere, the question is... where? maybe huge masses of matter generate some kind of subspace stream.. a rotation of small particles that only bump onto our molecules on the way to the matter, release their energy, go into subspace, and get back to where they came from to regather enough energy to be drawn again.

    this is just a theory though, but in the 10 minutes i thought of it ther was just 1 flaw. Who ever confirmed the existance of something like subspace?
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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    Who ever confirmed the existance of something like subspace? Nobody did and it might be some time before someone postulates a solid theory that incorporates 'sub-space'.


    I do not see the need for Gravitons to exist though. We have never detected them and even Einstein (In his General Theory of Relativity) stated that gravity was not a form of energy. Instead, he stated that gravity existed as a consequence of the fabric of the universe itself (It being curved).


    If Gravitons were to exist then they would have to be particles that can travel at infinite speeds which just makes no sense. For instance, if the black hole at the center of our galaxy were to just vanish the gravitational effects on our solar system would be instant. In that sense if Gravitons were real they would have to be travelling at infinite speeds - That cannot be. It makes much more sense to say what Einstein said.
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  14. #13  
    Universal Mind John Galt's Avatar
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    Quote Originally Posted by Chucky
    I do not see the need for Gravitons to exist though.
    I repeat - the other three fundamental forces all act through the medium of particles. It is reasonable to believe gravity does as well. If it does physicists find that they can fit such particles into their theories of fundamental particles and the like quite neatly.
    As I also indicated, not all physicists agree with this. It is possible to described the workings of gravity without resorting to gravitons.

    I am not a physicists. Therefore I shall accept, as a working hypothesis, the view held by the majoroty of physicists. As I understand it, this view is that gravitons probably do exist. Although not a humble person, I am not able to reject that viewpoint simply because I don't like it, or think it does not make much sense. I lack the qualifications to arrive at such a conclusion.
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  15. #14  
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    Quote Originally Posted by Chucky
    Isn't the existence of Gravitons in doubt? I mean, is gravity not an inherent characteristic of the universe? It is in-built into the fabric of space-time itself and is based purely on other energies such as electromagnetism. So why does there need to be particles such as Gravitons?
    Of course it is in doubt. Scientists attempt to fill holes in their understanding with hypotehtical entities, such as gravitons, dark energy, dark matter, etc. Gravitons are a possibility, but their value is as placeholders, until a better understanding comes around.
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    isn't the existance of the entire model for a normal based atom at doubt?

    nobody has yet seen it visually.. just by looking at the spectra of light that come from them..

    anyway.. maybe the answer is closer than we think..

    actually there's always the rule that said that the smaller we go, the more simple things get... i hope that also counts for the tinyest of all.
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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    Our limit to how far we can see matter is based on the wavelength of light. I mean, if a particle is smaller in size than the wavelength of light then we will not be able to see it. We would have to use waves of shorter wavelengths to detect (see) them.


    I do not think there are any fundamental particles - Rather, we could theoretically divide matter continuously but as the particles become smaller so do the wavelengths of the waves we must use to detect them. Similarly, in order to continuously divide the matter we would need larger and larger Particle Accelerators.
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  18. #17  
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    not just that... but it has to be vieuwed at a total vacuum, and weighlessness.. plus it has to be kept in place by a magnetic field (of some kind)

    then it'll have to be vieuwed with a 1*10^10000 frames a second camera (or almost endless)... and it has to be vieuwed with more than 1 camera with increddible magnification and even a bigger computer to make all the images to a 3d model of the atom.

    we can only achieve vacuum and weightlessness... just a small way left to go i guess... like 400 years
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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  19. #18  
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    im not scientist im just student of electrotehnical university but here my opinion if u think its dumb u
    can show it as example how man can be wrong :P, gravity itself must be observed on atom and molecular level
    cause in end that is what create mass, 1st there is 1 mine thery "no emission atom", atom that have no tendency
    to interact with other atoms in any kind of molecular connection iz gravity zerro atom, that is atom that have
    all electron orbit filed up, what make molecules to form it depend on i canot put it in englesh word cause
    my native language is not english but i think u understand it, there "Kovalentna" coneection i think it maybe
    "Covalent" and "jonska" maybe "ionic" connection, that is 2 forces that are in fact wery small in power, base
    forming of molecular connection is done by tendency of atom to make all his orbit full in reality molecular theory
    in chemystry work nice cause it say what atom can conect to other and what molecules can be created, but electrons
    have tendency to "excape" by adding some external force source (heat, temperature, magnetic feald, electrostatic feald)
    that will increase thir kinetic energy, well what happen then if we know that electron all time jump around like insane
    inside of any matery, there 2 scenarios, almoust all field strenght drop proporcional due lenght*lenght distance,
    and no matter how feald is small it exist and in theory can be detected, 1st scenario is colaps of a molecule sometime happen,
    second is that he owertake another electron from other atom or molecule, but what happen in interwal WHEN HE IS WITHOUT ELECTRON
    there is a field that activly atract electron but on other part athom ormolecyle that have that electron allso atract that electron
    due of stronger field and unconsistency of number of protons that atom or molecule have that electron is owertaken but what about
    atom molecule that had that electron it had been atracted to other atom molecule, as i remeber closer the orbit is
    it harder to owertake electron but if it around some lover number of proton athom he will be atracted bu energy conversion in
    orbit of that atom cause electron constantly change his potential and kinetic enrgy on depence of distance of core of athom
    in lovest kinetic and strongest potentional state other atom have most chance to steal it and atract it,
    but allso other atom atract it if u use this small field and multiply it with all numbers of athoms on earth and
    calculate field on distance from surface of earth i wonder what number ull get.
    there one question that my frend asked me, by this he say any field electrostatic magnetic .. wil make antygravity drive
    answer is no cause there alot electron thaty jump arond and asked to be atracted to something cause electrons always
    run around and new sorce of it is not ag drive.
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  20. #19  
    Forum Professor Zwolver's Avatar
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    if electrons make the mass... how can they have a mass? :wink:
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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  21. #20  
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    i didn generaly use term mass as system of generating force of atraction i saided that just simple lack of electrical balance in athom and tendency to fulfill it, cause that 2 atmos form molecular level if they are coresponding, or to atract each other due to lack of elctron from one side and tendency to owertake it from ALL ATHOMS IN UNIVERSE no matter how far it is, and tendency that other athom keep that elctron ill try to put this on paper, and if u know how much last in periods or time excaping and fullfiling excaped elctron, this will make this true or falce. cause i can only get + or - sign with constant, i canot get in final formula 0 or +infinity or -infinity due to extremimum of function.
    next u know formula for kinetic energy it simple it easy but if u make a mass of electron a zerro how much is kinetic energy :P, it in uper divider not in lower if u can put it in lower divider u could get infinity but cuase in upper u must get zerro for mass zerro, next thing energy continium or conwersion of energy where that what happen when electron head toward a athom what energy rise and what energy fall and same atraction of this ones that say all athoms around that electron wish to posses it and only one that have strongest field or its closest wil it have and allso in order to move u must have 2 thing REFERENT SYSTEM and mass, and bigest ilusion we have is that we maked referent system always good, cause i solved some realy hard things on just making referent system to be movable and u will be suprised how much things change and what solution on some problems u get that so inovative, i canot make examples im bounded by contract but u can try always to have referent system that reposiotion in behavior on some function that will make a bihaivor a linear or exponential function regarding moving ref system. then u recenter this function due to new still ref system and u get NICE THINGS.
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  22. #21  
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    The idea of gravitons comes from the fact that gravity reacts to changes with a finite speed. Relativity says that light is the speed limit of the universe, so in this way we on earth see the sun as it appeared 8 minutes ago due to the light traveling to our eyes having a finite speed. in this way, when a mass is moved on earth it is not immediately felt everywhere in the universe. There has to be some sort of carrier of this information to tell the rest of the universe that the mass has moved (analagous to light carrying the information of how the sun looks). as for proving the existence of the graviton, I'm not sure of that.
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