[Stephen Collins]

Stephen Collins  asked the Naked Scientists:
   
Is it possible that the gravity we experience is not an attracting force but rather a repelling one? 

I postulate a physics where a universal constant exists that repells matter. a VERY weak force in all likelyhood the 'fabric' of space itself acts against mass.  given the shape of the universe would this help explain its expansion and solve the missing mass problem.
 
I would love to get a proper oppinion on this and know if it is a previously rejected avenue or is something new.
 
Yours,

Stephen Collins of Brighton England.

What do you think?

[CliffordK]

Gravity is often described the 3-D equivalent of a 2-D "rubber sheet" in which each mass warps the sheet, and thus causing a tendency to flow towards that mass.

I'm trying to envision whether there is a real difference between an attraction vs a lack of repulsion from the background space vs a "warpage" of space.

[arobertson1]

Suppose objects with mass are not attracted to one another and are actually neutral to each other. Suppose they are actually repelled from an unknown force (call it whatever you like) and end up being pushed together. Wouldn't that appear to have the same effect as objects with mass attracting each other, especially if you couldn't work out what the unknown force was?

[imatfaal]

Suppose objects with mass are not attracted to one another and are actually neutral to each other. Suppose they are actually repelled from an unknown force (call it whatever you like) and end up being pushed together. Wouldn't that appear to have the same effect as objects with mass attracting each other, especially if you couldn't work out what the unknown force was?

But why make that supposition?  We have a very good theory of gravity (in fact we have more than one) that work and make testable predictions.  For a different theory we need a failures in current theories that are explained in new theory.

[arobertson1]

A good point. However it has been known for some time that the universe is actually accelerating with expansion. Something that gravity as we know it today should have actually slowed down, but it hasn't. So in many respects I would say that the theory of gravity has actually broken down.

[imatfaal]

There is definitely much still to discover - but we do not need to "throw the baby out with the bathwater".  Whilst we need to explain the universal expansion - a repulsive gravity needs to explain planetary motion, behaviour on earth, etc first. 

[arobertson1]

I quite agree that the existing theory should be kept until a more accurate theory is developed but it is clearly broken. Perhaps we are at the "phlogiston" stage of development with gravity as some of the theory works but ultimately it is wrong.

[imatfaal]

I can see your point - but the phlogiston theory failed at the earliest experimental hurdle and ws only supported due to its agreement with proponents' preconceptions.  The combination of newtonian gravity and einsteinian g relativity fits very well indeed with experiment

[RD]

Suppose objects with mass are not attracted to one another and are actually neutral to each other. Suppose they are actually repelled from an unknown force (call it whatever you like) and end up being pushed together. Wouldn't that appear to have the same effect as objects with mass attracting each other, especially if you couldn't work out what the unknown force was?

http://en.wikipedia.org/wiki/Le_Sage%27s_[failed]theory_of_gravitation

[Geezer]

I postulate a physics where a universal constant exists that repells matter. a VERY weak force in all likelyhood the 'fabric' of space itself acts against mass. 

You could be right. All you have to do is to come up with a mathematical expression that accurately describes the phenomena we observe in terms of the forces you are predicting.

When you do that, I'm pretty sure a lot of people will pay very close attention.