Gravity has mass

[deltadrone]

Brian334,
   Look at the asteroid belt.  There is a lot of mass in the belt however not enough large bodies to cause the coalescing of a planet.  A case where there is lots of mass spread out preventing the forming of a planet. So even though these asteroids will not make a planet, they do have gravity. 
How each one has its one, each is different than another.  One may have a large mass but little gravity due to lack of density(a light rock of sandstone).  When another has less mass but greater density(a granite rock) giving it a greater gravity.

Delta

[onthecuttingedge2005]

does electricity or magnetism have mass?

solar sails are powered by light, which doesnt have mass but has the capacity to become mass


gravity is a storage device for potential energy.

so i guess gravity is merely a form of potential energy, and i dont necessarily consider energy to be mass

Simple rules here, anything that 'occupies space' will 'displace space' and therefor has a Gravitational influence, this includes Photons and the lot.

Gravity is a Tensor Field.

Jerry

[brian334]

Delta.
How do you know small objects have gravity?
Has it ever been measured or is it just a theory?

[ATT]

.
Since this is all 'half baked' and I really don't know the answer, here's some thoughts that come to mind as a 'layman':

We are told that at the atomic level, a particle's 'mass' is gauged by it's 'charge', so rather than atoms being actual material 'things' the way we think of 'things', they would seem to be made up of various foci of 'charge'.

At the macro-level, we get used to discriminating between matter and energy, mass and gravity, conductor and insulator but as we descend into the constituent makeup of elements at the atomic level, we find that the sub-atomic particles manifest properties as the result of 'observation' and blink in and out of existence more as a 'cloud' rather than the more popular depiction of a 'solar-system' with electrons orbiting a nucleus.

The popular description for gravity is a depression in space-time resulting from the presence of a mass, the more mass, the more gravity, but nobody knows for sure, it's all hypothetical.

If you had occasion to read through New Scientist for Jan-17 2009, you may have encountered the 'holographic' article, where it's surmised that the Geo600 project in Germany may have sensed the limits of space-time and it's further surmised that those limits may imply that the world we perceive may be nothing more than a 'projection', the question, if this proves to be the case, is 'who' is controlling the source-data that produces the projection?

I have a pdf of the original article available, but it's too large to upload to this server.

It'll be about a year before any final determination can be made since they have to eliminate any other possibility of transient 'noise' being the cause for there initial findings.

Does gravity have mass? As our present understanding goes, it would be just as correct to ask: Does gravity have 'charge'? We can measure it's effects but 'what' exactly it 'is' has yet to be discovered.
.

[brian334]

The important question to ask is can gravity transfer mass?
For example can gravity transfer mass from the earth to the sun?