Gravity repels

[gblaze42]

you would basically see a clump of dense +g matter and -g matter moving away from each other. Why this doesn't seem to be is that the cosmic background noise should show this disparity and it doesn't.

Cool. I was hoping for something definitive to close down this line of thinking. I get a lot of intuitive ideas and sometimes, if I don't let out, they keep coming back and distracting me. Thanks for your time.

Well don't let it discourage you from trying, ever. We need people who are at least willing to push the boundaries.

[krenshala]

you would basically see a clump of dense +g matter and -g matter moving away from each other. Why this doesn't seem to be is that the cosmic background noise should show this disparity and it doesn't.

Cool. I was hoping for something definitive to close down this line of thinking. I get a lot of intuitive ideas and sometimes, if I don't let out, they keep coming back and distracting me. Thanks for your time.

Well don't let it discourage you from trying, ever. We need people who are at least willing to push the boundaries.

And sometimes it takes refuting a really crazy out-there idea to firm up our understanding of how things actually work.

[chrismb]

Maybe its just that opposite charges electrostatically attract each other slightly more than like charges repel.

[MSimon]

Maybe its just that opposite charges electrostatically attract each other slightly more than like charges repel.

You would think that would have been noticed by now.

[chrismb]

You would think that would have been noticed by now.

They did. Newton noticed 400 years ago, but seeing as no one new about electrostatics then, so he got us all confused.....

[MSimon]

You would think that would have been noticed by now.

They did. Newton noticed 400 years ago, but seeing as no one new about electrostatics then, so he got us all confused..... :)

Wise guy.

[Tom Ligon]

Hmmm, if an assymetry in electrostatic forces like that exists, it is probably as significant as finding antigravity.

Read that Cramer piece (yes, the article linked above seems to be the same as the Analog "Alternate View" column) and see if it is likely the apparatus described could discern the difference between an electrostatic charge assymentry and an actual gravitational force. I think it should. They excite the particles with microwaves, and shield them electrostatically. The goal is to generate gravity waves by vibrating one particle, and look for an effect in a second particle, transmitted solely by gravity waves.

Of course, they haven't actually done this yet, so a negative result may argue for Chris's explanation.

[kttopdad]

A 'force' is the integral of rate of change of energy wrt distance.

I would suggest the following change in wording: "A measure of 'force' is the entegral of rate of change of enerty wrt distance." We don't actualy know what "force" *is* - we just know how to describe it in terms of work, etc.

[chrismb]

I would suggest the following change in wording: "A measure of 'force' is the entegral of rate of change of enerty wrt distance." We don't actualy know what "force" *is* - we just know how to describe it in terms of work, etc.

This is *my* definition.

The point I am highlighting is that we don't actually have any reason to suppose forces exist, only that they fit our perception. We measure forces *by* measuring how they affect the energy state of a closed, given, well-defined system (e.g. a spring or a balance). A force *is* the integral..&c...

[zenakuten]

You've conjured up some ideas, but just because you can imagine them, it doesn't make it right or possible. I think there are many such ideas on gravity. Here's mine:

In my humble analysis; gravity is often mistaken for a force that has mediating particles (thus the 'confusion' over the Higgs boson).

Firstly, I need to say (again) that forces do not, literally, exist. They are figurative representations of change of energy, which in turn are changes of state. A 'force' is the integral of rate of change of energy wrt distance.

Gravity is experienced as a force not because it is a mediated exchange of energy, as per the *other* forces, but because it is the rate of change of configuration of matter that would *otherwise* occur were those lumps of matter to diverge at the expansion rate of the Universe. That is to say, the earth and you are being pushed apart by the expansion of the Universe. But to be pushed away from such a large mass requires energy, because that would be a change of state, as each elementary particle that makes up your body forms its own 'microstate' with each and every other elementary particle of the earth. Hence, this effect is proportionate to the product of the two bodies' masses.

That energy cannot simply pop into existence, so instead you experience an incipient resistance to that expansion in the form of what appears to you to be a force. No energy is expended whilst you remain 'in geometrical stasis' with the Earth, only when you move radially to it. Thus, I say gravity is the same force as if you were to push (accelerate) an object away from you as you change its, and your, state of momentum. But you've got energy in your arms to do that, whereas the expanding geometry of the Universe doesn't have such energy built into it, so instead it appears the exact opposite of that scenario - that those two object are actually attracting each other. It is a consequence of incipient change of state, not as a force acted by a source of energy.

Because of this, gravity is not 'dipolar', as are electricity or magnetism, it merely applies to all matter whilst the Universe is expanding. Eventually the Universe will stop expanding and gravity will drop to zero. It will finally begin to collapse, and gravity will reverse and then become repulsive to all matter.

I am therefore predicting two things a) no mediating particle for gravity will ever be found and b) the gravitational constant will change over time, as a function of the rate of expansion of the Universe.

[The expansion of the Universe may not be fully uniform either, as the Universe itself is like a 'front' of higher density material propagating through another (in this case, another dimension) so that expansion rate, and gravity, may not be easily measurable to a highly accuracy value at a given moment in time and location in space.]

I have a very similar view. Researching this view has lead me to heim theory. I do not understand it. A translation of his original introduction can be found here. In his introduction he makes a similar claim, but also ties in the flow of time with the expansion of the universe and the gravitational force. According to heim, all three are related. Also, he claims that gravity between two particles is repulsive at distances > 20 light years. It's not really repulsive, more that that matter attracts matter, but matter repels space, so that the expansion of space between them at 20 light years is greater than the attraction from gravity.

Even if he's wrong I like his approach. He's very careful about what are defined as fundamental, e.g. speed of light is not fundamental, but rather composite of permittivity and permeability fundamentals (C = sqrt(1/e0m0).

I knid of like the hypothesis that gravitation only repels. Each particle is repeled by gravitons from every direction continuously except where other mass has shaded that particle from one direction. In that case, the shaded particle is pushed preferentially in the direction of the shading particle.

Correct me if I'm wrong but I believe this is a description of the higgs mechanism.

[hanelyp]

Maybe its just that opposite charges electrostatically attract each other slightly more than like charges repel.

If that were the case, you'd expect the ratio between inertial and gravitational mass to vary with nuclear binding energy. I recall an experiment several years ago looking for that. As far as I know it came up with the expected null result of no difference.

[hanelyp]

...Also, he claims that gravity between two particles is repulsive at distances > 20 light years. It's not really repulsive, more that that matter attracts matter, but matter repels space, so that the expansion of space between them at 20 light years is greater than the attraction from gravity. ...

That sounds like gravity falling off faster over galactic distances. Galactic motion data, on the other hand, suggests gravity from visible matter as described by accepted theory is too weak to hold galaxies together.

[krenshala]

...Also, he claims that gravity between two particles is repulsive at distances > 20 light years. It's not really repulsive, more that that matter attracts matter, but matter repels space, so that the expansion of space between them at 20 light years is greater than the attraction from gravity. ...

That sounds like gravity falling off faster over galactic distances. Galactic motion data, on the other hand, suggests gravity from visible matter as described by accepted theory is too weak to hold galaxies together.

Is that taking into account the carbon "ash" (I don't remember the exact name, but I think that was it) that was found to exist in the interstellar medium?

That carbon dust/ash is also believed to red-shift light from stars, thus leading to incorrect distance figures, among other things. From the article I read on it last year, it was estimated that this dust could, by itself, account for the perceived "expansion" of the universe as shown by red-shift.

[hanelyp]

Is that taking into account the carbon "ash" (I don't remember the exact name, but I think that was it) that was found to exist in the interstellar medium?

As I recall, the dark matter required to account for the difference between the mass we can see and the mass the should be there based on theory is several times the mass of what we can see in most galaxies. That would be a lot of carbon ash between the stars.

That carbon dust/ash is also believed to red-shift light from stars, thus leading to incorrect distance figures, among other things. From the article I read on it last year, it was estimated that this dust could, by itself, account for the perceived "expansion" of the universe as shown by red-shift.

How is this red shift supposed to work without imposing a telltale spectral imprint?

[KitemanSA]

There was an Indian fellow who's name escapes me who hypothesized (if memory serves) that matter is being created all the time and the new matter takes a while to become fully quantum entangled (?) with the rest of the matter in the universe. Until it does, it has less mass than old matter and thus will put out radiation with less energy, i.e. well red shifted. This matter is created by mechanisms I didn't catch in galactic centers and ejected in big lumps. Because the lumps are brand new, they are very red shifted, and folks think they are very far away. Thus they seem HUGELY brighter than they really are. We call them quasars.

This may be somehow entangled with other thoughts in this thread or others. Just thought I'd bring it up again cuz it is so mind-numbingly interesting.