What causes gravity?

Question

Please dont answer "mass". This doesn't cause gravity. There must be a property of mass that causes the effect of gravity. I'm open to ideas and speculation here but please - keep it intelligent.

Answer 1

There is a quantum theory explaining the four fundamental forces from weakest to strongest:
Gravitational force
electromaganetic force
weak nuclear force
strong nuclear force

It states that all of these forces can become one under the proper conditions, but it also names four particles responsible for them. They are (respectively):
Gravitrons
Bosons
Gluons
Quarks

Scientists beleive that these partices are responsible for gravity, but it is the only particle of the four that has not been found yet. There is some debate on such a particle, its existence an d location. Until then, scientists can stick to Keppler's law on Universal Gravitation. I believe it has already been mentioned, so I won't be redundant.

But in the law, the main deciding factor of the law is mass. Radius affects the reulting value, but mass is the key to gravity.
We are drawn to the earth because we are less massive, and we are close, but that is with all objects, not just enormous ones. For instance, if one was to float in space with an ant, the ant would begin to orbit the person because of the masses and the distance between them.

Hope that helps

Answer 2

It would be good to define gravity. I think a good definition is this: gravity is the tendancy for objects of positive mass to appear to accelerate towards each other.

Einstein suggested that the more massive an object, the more it will bend the space around it. This would mean that objects do not necessarily feel a force, but that objects instead move through a curved space and, therefore, seem to be affected by a force.

As for a deeper answer, there really is none at this time. To reconcile the description of the universe given by quantum theory with that given by general relativity is a task not yet accomplished.

I would be interested to hear why you are sure that mass does not cause gravity. What is your definition of mass, or of gravity for that matter?

Answer 3

Ok... Back from my A-level days, the answer is Mass.

If you want a more "particular" answer (excuse the pun)... I direct you towards Particle Physics. Every thing that happens is a result of an interaction. There are four types of interactions, Strong, Weak, Electromagnetic, and GRAVITATIONAL. These are fundamental, just like fundamental particles or fundamental units... these interactions explain EVERYTHING.

Now in every interaction, there are exchange particles that jump from one substance to another... causing the attraction, repulsion or transfer of energy (mass=energy... from theory of relativity). There are many excahnge particles from electrons to Z0, Z-, Z+ and so on. But in the case of Gravitiational interactions... the particle involved is the GRAVITON. The exchange of Gravitons from matter to matter is the fundamental cause of attraction between them... thus the energy change is in the form of the attraction.

I should also say that Gravitons can't actually be detected and are a theoretical particle. I hope this helps!

Answer 4

Gravity... it is defined as a force with which the earth tries to bound everything towards itself. As since every force has its strength over a distance so as you go farther from earth the force decreases and hence gravity. Gravity is basically due to the earths magnetic field. It is assumed that there is a large magnet inside the earth and is constantly rotating in conical motion.

Answer 5

well there is this law that stats that all matter in the universe attract each other mutually.(newtons law i think)
So according to this forces of attraction will be greater for larger objects as they have more atoms and can attract more.
this causes gravity and also mass is another reason why gravity is greater
actually you are also producing gravity on another person

to fid this out you have to use this eqn
GMeM
----------
Re^2

where G -= 6.67 * 10 ^ -11
Me = Your mass or the planets mass
M = Other objects mass
Re = distance between two objects.
This is one of NEWTON's Laws.
it has also been proved in quantum physics.

Answer 6

if you believe the String Theory, there are little loops of "string" that can travel between the different planes, they are the cause of gravity, wouldnt it be neat to have a gravity phone to talk to the other dimensions

Answer 7

Early history

Since the time of the Greek philosopher Aristotle in the 4th century BC, there have been many attempts to understand and explain gravity. Aristotle believed that there was no effect without a cause, and therefore no motion without a force. He hypothesized that everything tried to move towards its proper place in the crystalline spheres of the heavens, and that physical bodies fell toward the center of the Earth in proportion to their weight.

Another early explanation was that of the Indian astronomer Brahmagupta who, in his Brahmasphuta Siddhanta (628), responded to critics of the heliocentric system of Aryabhata (476-550) stating that "all heavy things are attracted towards the center of the earth" and that "all heavy things fall down to the earth by a law of nature, for it is the nature of the earth to attract and to keep things, as it is the nature of water to flow, that of fire to burn, and that of wind to set in motion... The earth is the only low thing, and seeds always return to it, in whatever direction you may throw them away, and never rise upwards from the earth."[1][2]

Modern work on gravitational theory began with the work of Galileo Galilei in the late 16th century and early 17th century. In his famous experiment dropping balls at the Tower of Pisa and later with careful measurements of balls rolling down inclines, Galileo showed that gravitation accelerates all objects at the same rate. This was a major departure from Aristotle's belief that heavier objects are accelerated faster. (Galileo correctly postulated air resistance as the reason that lighter objects fall more slowly.) Galileo's work set the stage for the formulation of Newton's theory of gravity.

Newton's theory of gravitation

In 1687, English mathematician Sir Isaac Newton published the famous Principia, which hypothesizes the inverse-square law of universal gravitation. In his own words, “I deduced that the forces which keep the planets in their orbs must be reciprocally as the squares of their distances from the centers about which they revolve; and thereby compared the force requisite to keep the Moon in her orb with the force of gravity at the surface of the Earth; and found them answer pretty nearly.”

Newton's theory enjoyed its greatest success when it was used to predict the existence of Neptune based on motions of Uranus that could not be accounted by the actions of the other planets. Calculations by John Couch Adams and Urbain Le Verrier both predicted the general position of the planet, and Le Verrier's calculations are what led Johann Gottfried Galle to the discovery of Neptune.

Ironically, it was another discrepancy in a planet's orbit that helped to doom Newton's theory. By the end of the 19th century, it was known that the orbit of Mercury could not be accounted for entirely under Newton's theory, and all searches for another perturbing body (such as a planet orbiting the Sun even closer than Mercury) have been fruitless. This issue was resolved in 1915 by Albert Einstein's new general relativity theory. This theory accounted for the discrepancy in Mercury's orbit.

Although Newton's theory has been superseded, most modern non-relativistic gravitational calculations are based on Newton's work because it is a much easier theory to work with and sufficient for most applications.

Answer 8

just like every thing has their own gravital attraction

gravity is made just for the sake of being

Answer 9

the rotation of the earth

Answer 10

the earth's magnetic field.