M-Theory, dark matter, and gravity.

While I am a physicist, I worked in thermal physics and alloys, and this is about M-theory and particle physics, so I'm looking for some input of perhaps a PhD or at least a well read or math oriented science nut.

I know that M-theory sugest that gravitons are particles given off by mass particles (Higgs boson?) and that these graviton transmit gravity via extra dimension. So we have gravitons moving in and out of our brane, warping space-time, and centered around mass.

Now, this means that OUR universe, our brane, is effecting the topography of other branes, correct? So where earth exist in our brane, the coresponding location in other branes may have high gravity, even with a lack of mass.

Is it not possible then that there is no dark matter? But rather gravity leaking into our brane from masses in other dimensions? These seperate branes effecting eachother through a shared particle, the graviton?

In reading a laymens guide to M-theory it seemed very clear that it predict gravity to be just as strong as any other force but acting outside our brane as well as in it. I would think it would be a small step then to say that dark matter is actually not there, but rather matter in another dimension is causing gravity effects here.

Does anyone know to what extent this idea has been looked at?

Let me tack on a few bits of to this for the rest of the ATS community who isn't into the hard end of physics.

If M-theory is correct, gravity can pass between branes (sort of like parallel universes). This means that while light, matter, and energy will never be transmitted between us, gravity could be. A focused beam of gravitons could then in theory be used to communicate with other dimensions.

If a race figures out what proprties of the graviton allow it to move between brains, and duplicate those properties in other forms of particles, possibly even mass trasport between dimension could be possible.

The heavy gravity from "dark matter" could actually be mass gravity probes from other branes looking for intelligent life in our universe.

Just some fun, far out ideas for people to talk about while i wait for a PhD in theoretical physics to stumble on this post.

While I am only an A-level student in Physics, I do have a degree of knowledge, I think, in M-Theory, etc
M-Theory is an explanation for the weakness of the gravity force...

However, I think it is somewhat impossible for us to replicate the Graviton for the use of transportation of mass between branes because simply it just isnt compatiable, for example;
Two sheets of paper represent two different 'branes'. Anybody living on those branes are not aware of the other, but the other brane can be literally milimetres away from the first one... Now, to pass particles between branes, you would need some sort of interaction between branes to create a 'wormhole' between them, but then, you need to consider the fact that there is a theory that everytime branes interact, we have another big bang..

However, I dont think the graviton theory supplements dark matter. From my understanding, vacuum energy and dark matter are not really interacting on this level, especially if you consider the fact that gravitons escape our detection so quickly that they must basically be travelling trans-brane at very high speeds, but perhaps we will in the future be able to detect gravity 'wells' where 'earths' or black holes on other branes exist near to our branace..

I understand that there is the possibility however of using gravitons in some form of binary to begin basic communications trans-brane, but I'm not sure how this is going..

This is only my understanding, and not any form of solid theory! =)

browha

Thanks for the input.

One thing, I think the theory says a bog bang will happen when the brane collide at a point, not just share a particle like the graviton.

I doubt we are trying graviton binary yet, we still have to prove supersymetry (can't wait for CERN to come online). I doubt we have that level of conrol yet. But you never know with government science being so far ahead of the public.

The theory looks good so far, though it still has a few little things to work out here and there.

I meant that one way we could interact would be to open up the branes to each other, like a tunnel,
as in literally a tunnel between two branes, like imagine two puddles, next to each other, but unable to interact
then if you open up a tunnel/channel between them, they are able to flow freely into each other, almost acting as if one puddle/brane

the major break through was converting the various forms of string theory into one large M theory!

Hrmm i dont think it could work like that. For instance. If in another dmension there is a Sun the same size as ours. And somehow that sun got swung out of orbit and started heading in it's part of the universe, towards where our planet, Earth, Would be in it part of the universe...Get my drift...

hang...

o - Earth
------------ - Something seperating 2 dimensions? ;P
/\ - Arrow showing suns direction
|
O - Sun in a different universe

Now even though both objects stay in their dimensions, you are syaing that some gravitational pull from the Eartha nd from the Sun can be felt in both universes. Now if that were true, If that sun got to close to Earth and the gravity was strong enough (or even still weak but still tehre and still problematic), wouldn't that Suns gravity pull the Earth out of orbit, or change it's orbit enough so that it might slow down ,get flung out of orbit, cause massive Earth changes, be a pain in the butt?


Anyways i'm still trying to figure out how gravity works. A recent experiment said gravity moves at the speed of light. So if the Sun were to disappear, we would still follow around in orbit for 8 mins, then we would just head in a straight line into space....So if the Sun were suddenly put back, it would take 8 mins for us to feel it's gravity. It's like a sucking in motion that moves out at the speed of light.

Now even though both objects stay in their dimensions, you are syaing that some gravitational pull from the Eartha nd from the Sun can be felt in both universes. Now if that were true, If that sun got to close to Earth and the gravity was strong enough (or even still weak but still tehre and still problematic), wouldn't that Suns gravity pull the Earth out of orbit, or change it's orbit enough so that it might slow down ,get flung out of orbit, cause massive Earth changes, be a pain in the butt?

Yes, exactly. And that would the the explination behind dark matter. There are many observerd galaxies that seem to have much more mass then they have based on measures of gravity. These observations are of areas where other branes have mass centers as well.

This would probably mean that much of the milkyway also shares gravity with other dimensions. And yes, if a star or other large mass in another dimension swung near us, it would trow the earth off, EXCEPT we are stable now, which would sugest so is anythign we are connected to via gravity.

If indeed gravity can pass through to ther dimensions, this would mean we are and always have been tied to other masses.

The only way to verrify any of this is to first confirm M-theory, then to find a souce of gravity with no mass involved (dark matter).