what is gravity?

Question

specifically what causes this force, no answers like mass or the like i mean details, inter atomic forces is not a valid answer either unless you explain what that is (to my knowledge noone knows but i could be wrong)

my god why are people answering with god answers, this is a science section isnt it?

why are loads of people saying gravity is the force that keeps us to the ground or some variation... i mean think about it, if i didnt know that do you really think id know how to create a yahoo account and ask a question on this thing?

Answer 1

Ok, you seem quite bright so I'll try and explain. First of all I'll have to explain what a geodesic is. A geodesic is the shortest possible line between two points. i.e. so on a flat surface it is a straight line, on the surface of a sphere it is a great circle. Geodesics also exist in higher dimensional space. According to general relativity objects which aren't accelerating (other than by gravity) follow these geodesics through 4-D spacetime. In other words they are taking the shortest route between two points in spacetime. (note this is NOT the same as the shortest route between two points in space.)
Away from any large masses, where there is no gravitational field, spacetime is 'flat'. Here the geodesics mean that the object either does not move or moves with constant velocity. Near large bodies spacetime is curved. Here the geodesics take a different form this means that the object accelerates rather than staying at the same velocity. This acceleration is what we see as gravity.

Hope this makes some sense. To understand it in more detail you need to study general relativity.

Answer 2

To be totally honest, nobody really knows.

The standard explanation is Einstein's concept of a universe which is like a rubber mat, and that matter acts like a heavy weight placed on the mat. If you then put something small on the part of the mat which is curved downwards by the weight, it will roll towards the heavy weight.

Unfortunately this still leaves a lot to be explained. The small object only rolls towards the large object because of gravity acting downwards through the mat. So all it does is explain gravity in terms of gravity!

Also we have no idea why it is that matter 'warps' space in the first place.

Scientists are currently using particle accelerators to try and detect the Higgs boson, which is supposed to be the source of mass, and the Graviton which is supposed to be the particle which produces the force of gravity. If they ever find them (which I personally doubt) we may have a better idea of what actually causes the force of gravity.

Answer 3

The force of gravity performs work. In order for work to be performed an energy source is required. What needs to be determined is: (a) the source of gravitational energy, and (b) what relationship exists between to two in order to form this forced.

First, This force is always related to mass. What is a feature of our planet that would indicate what the energy source might be? A feature common to our planet, as all large solar bodies, is that of their shape. They are all spherical. Were a mass the size of our planet to be the shape of a cube, it would remain that way. But, were a large amount of heat energy added to the mass, it would assume the shape of a sphere. What does heat energy have to do with the force of gravity?

There is a physics trilogy that explains why this relationship exists. The trilogy is: E = mc2, m = E/c2, and c2 = E/m. It is the last equation we are interested in. It describes how a gravitational field forms. It is a relationship between mass and energy, and where one of the two values change, the result of the two will also change.

Gravitational waves below the "Moho" discontinuity all focus through the center of our planet and exit out the other side of it. It is for this reason our planet is the shape of a sphere (oblate sphereoid to picky people). The energy of gravity also attracts the heat energy of our planet toward its center. Were this beneficial fact not true, then our planet would be almost the same temperature throughout.

http://timebones.blogspot.com the last half of "The Problem and Repair of Relativity" describes how the above may emperically be proven. This same two page work is also on my blog here at Yahoo. It is entitled "An Experiment You Can Help With."

Answer 4

Gravity is one of the strongest forces in the universe, Yes we will need to mention mass, All objects with mass emit a very small amount of gravitational pull, but you don't feel it. This gravitational pull may be as strong as 100th of a gram, depending on the source. To my little brother, the GameCube emits the strongest attraction known to man :P. The greater mass something has, lets say trillions of tons and growing millions each day like the Earth, the greater magnetic attraction it exerts. You are right, we DO NOT know EVERYTHING about gravity, but we know alot. If you even want a Wikipedia search on gravity, here it is.

http://en.wikipedia.org/wiki/Gravity

I hope that I was able to help, contact me with any more comments, questions, etc.

Answer 5

this may be completely wrong but here goes. i believe i have seen gravity demonstrated like a sheet stretched out with objects placed onto it. where the object is placed onto it the sheet sinks down and the higher the mass the lower it sinks. this is similar to the way gravity behaves in that the higher the mass the stronger an objects gravitational attraction is. i believe the point that this demonstration was trying to make is that mass disrupts the space around it and when two of these fields overlap there is a gravitational force of attraction between the two. I'm not sure if this helps but you never know

Answer 6

According to a theory, gravity is supposed to be formed by the warping of the space-time fabric. An object with significant mass causes the warping of the space-time fabric, which inturn causes all the less significant objects to follow the warping effect. The gravitational force was thought of as very weak, and insignificant compared to electromagnetic force, but theories now exist that state that the force appears to be weak because of the leaking effect in the multi-dimensional parallel universes.

Answer 7

If you think of matter in a different way it makes sense, but it looks like physicists are creating a new theory to account for the anomalies of gravity. If you think that all matter is made of atoms, which are made of subatomic particles that have either a positive or negative charge (ignoring the neutrons), then, knowing that these attract eachother, it is easier to think that they would pull together. I know that this is not the 'correct' way to look at it, but it can make it easier to accept.

I personally like the idea that when matter comes together, it pulls together in an effort to fight the evil force of chaos - wonder twin powers activate. LOL

Answer 8

In physics, gravitation or gravity is the tendency of objects with mass to accelerate toward each other. Gravitation is one of the four fundamental interactions in nature, the other three being the electromagnetic force, the weak nuclear force, and the strong nuclear force. Gravitation is the weakest of these interactions, but acts over great distances and is always attractive. In classical mechanics, gravitation arises out of the force of gravity (which is often used as a synonym for gravitation). In general relativity, gravitation arises out of spacetime being curved by the presence of mass, and is not a force. In quantum gravity theories, either the graviton is the postulated carrier of the gravitational force[1], or time-space itself is envisioned as discrete in nature, or both.

The gravitational attraction of the earth endows objects with weight and causes them to fall to the ground when dropped (the earth also moves toward the object, but only by an infinitesimal amount). Moreover, gravitation is the reason for the very existence of the earth, the sun and other celestial bodies; without it matter would not have coalesced into these bodies and life as we know it would not exist. Gravitation is also responsible for keeping the earth and the other planets in their orbits around the sun, the moon in its orbit around the earth, for the formation of tides, and for various other natural phenomena that we observe.

Answer 9

Gravity is the tendency of particles floating about in space to group together and form clouds. These clouds eventually form stars and planets. The more particles in a group, the more that group tends to attract other particles. The attraction all adds up.

So two particles (or two clouds of particles or two planets) will tend to drift towards each other. They are attracted by the force we call gravity. It's a very weak force that acts over very large distances.

Answer 10

With all those restrictions, you ain't gonna get any answers dude. I could have a stab at answering, but it would take a couple of days, so could I instead direct you to Amazon where you will find some very interesting books on the subject.

Gravity is what keeps your beer in your glass till you tip it down your gullet!