what really is gravity?
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to date, the best description of gravity is given by general relativity.  general relativity was published in 1915.  however, physicists are trying to develop a more accurate quantum description of gravity because of the contradictions between general relativity and quantum physics.  both general relativity and quantum physics are supported by incredibly precise observations.\n\nhttp://en.wikipedia.org/wiki/General_relativity\n\nthis is really bizarre.  it is the holographic universe.  the name comes from the hologram, which is a two dimensional film that has information stored on it and will project a three dimensional image, if laser light is put thru it.  physicists can describe the universe with two sets of laws: one three dimensional set with gravity and one two dimensional set without gravity, and there is no way to tell them apart.  this second set essentially states that gravity is an illusion.  see "the illusion of gravity", scientific american, november 2005
939929
A gravimeter is a device designed to measure the local gravitational field. Also sometimes called a gravitometer, a gravimeter is a type of accelerometer. According to the equivalence principle of Albert Einstein, the effects of a gravitational field are rigorously equivalent to acceleration. Therefore, gravimeters are susceptible to vibration which causes small, oscillatory accelerations. This is counteracted by integral vibration isolation and signal processing.
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I think it is more accurate to say we can easily replicate the EFFECTS of gravity, rather than gravity itself.  Gravity relies on mass.  More mass, more gravity.  Any "replication" of real gravity is not replication it is the real thing.
42159
I'd love to know what your answer is. Its actually something physics seems very confused about.\n\nAccording to GR, its masses that cause the curvature of space. Gravity isn't a force, its just masses following the path of least resistence - straight lines in curved space time.\n\nThe problem is they then try to introduce gravitons to carry what isn't really a force. Very confusing.\n\nIf we assume Einstein is right, that gravity isn't a force, but masses following curves, the real question becomes - where does mass come from?\n\nMy guess - quantum entanglement create at time zero that keeps everything in the universe interacting. I don't like the higgs bogusons theory, since that introduces yet another force carries in the terms of a, erm, massive particle that gets mass from, erm, itself...
819820
Gravity is everwhere but less or more, depends on the matter.
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Universal Law of Gravity.\nALL objects attract each other with a force of gravitational attraction. This force of gravitational attraction is directly dependent upon the masses of both objects and inversely proportional to the square of the distance which separates their centers.\n\nWhere ever you are gravity has got you some way, however weak, something somewhere will be pulling you towards it.
1130053
As mentioned in other replies, physicists don't yet have all of the "how" questions answered. Einstein, in the General Theory of Relativity, pretty much nailed the underpinnings of the current theoretical understanding of gravity. Here is my attempt at the "nutshell." I'll start with an analogy. Let's say you are driving somewhere in the midwest or plains states--essentially flat ground, with a few rolling hills. Let's say you stop your car at the top of a slight rise. As you look around you, you see flat land in every direction. You're sitting on essentially a two-dimensional plane. Taking your foot off the brake, you notice the car starting to roll forward. Your initial observation about the 2-dimensional "space" you were sitting on isn't quite accurate. The 3rd dimension (altitude) has come into play, and gravity is pulling your car into the swale. What Einstein said (and how he came up with this back in the early 1900's is incredible) was that our THREE dimensions are really a slightly inaccurate description of the world (and universe) we inhabit. A fourth dimension, time, is part of the "fabric" of our surroundings. As in the case of that slight "warp" in the 2-dimensional farmland that led to a noticeable effect on your car, Einstein said that warps in the space-time continuum are experienced as gravity. As you know, Einstein was into the "energy = mass" thing big time, and you know that mass is tied up with gravity as well. If you want to get more cozy with these related concepts, I strongly recommend David Bodanis' book, "E=mc2: A Biography of the World's Most Famous Equation" -- available as a "BooksOnTape." It's exciting, full of cool anecdotes about the heroes of 20th century physics, and... NO MATH, just concepts. Best of luck!
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There are two way to look at it.\nIn Relativity, gravity isn't thing itself just a bending of space. Just like a bend in the road is only a way to describe something about a road.\nIn Quantum Mechanics, gravity is actually made up of Bosons (particle carriers of force) called Gravitons. To date gravitons are purely theoretical since no one has manages to observe a graviton yet.\nWhile this may sounds weird, both are correct.
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Gravity is defined in a new term.  That is the latest report\n    of the atomic relativities of the quasar versus the quantum\n    in an isolated directive.  Defined by the mineral interactions.\n    What?  Gravity has the interactive quantities added to the\n    average force of one planet attracts to another Plus the ionic\n     pentanmeters(depends on the substance with conditions).\n    So gravity is present in all materials if left in free space, or put\n     into orbits, or put on a plane.  This last set is the theoretic\n     gravity of space infinitives to the nth degree, showing that all\n     materials have the origin of gravity values as established at\n     the desk of the elements chart, and its properties.  The flight\n     of planets is a true measure of gravities, showing such things\n     as anti-gravity points like in a space capsule.  The interaction\n      really never out drives the elements chart standard.
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The scientific definiton of "theory" is not what your average person on the street would think it is.  It is NOT a hypothesis, it is NOT just a clever idea that sounds right.  It is something that has been supported over and over again, in all aspects of biology.  \nEvolution is a theory, and so it gravity.  Gee, better start arguing against that, too...
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and gravity does what?\n\nand why don't you fall off?
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Gravity is the force of attraction between massive particles. Weight is determined by the mass of an object and its location in a gravitational field. While a great deal is known about the properties of gravity, the ultimate cause of the gravitational force remains an open question. General relativity is the most successful theory of gravitation to date. It postulates that mass and energy curve space-time, resulting in the phenomenon known as gravity.\n\nGravity is acceleration.  means that (if the mass is unvarying) there must be a force that causes a mass to accelerate. For a rocket ship, that is the rocket engine. For the earth, it is the compression of the mass between something on the surface of the earth and the earth's center of mass. The acceleration is in relation to spacetime in that the weight one feels is one's resistance to deviating from one's path in spacetime. The same holds true in the rocket ship except that a rocket engine supplies the force to accelerate an occupant from his spacetime path. There is no difference between the weight he feels because of gravity or the rocket.
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Hi, its not gravity but a force opposite to gravity that prevents a boat from sinking and keeps an airplane in the air. Sorry, but I forgot the name of the force, I think it begins with a B. O, the second person said it- Buoyancy.
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What is this gravity that you mention?  :P\n\nGood point tho, funny how it didn't exist until very recently in our history.  *hugs*
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How do we believe in Gravity yet we do not see it?\n\nRomans 1:20\n20For since the creation of the world God's invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that men are without excuse.
1114043
Gravity is the force that holds everything down. Gravity also affects different people depending on their body mass. It you are taller, you have a greater gravitational pull on you which makes you weigh more.  The force of gravity is strongest when it is closest to the core of the Earth. The closest that we can get to the core of the Earth is sea level. So you would weigh more at sea level than you would on a top of the mountain. You would still have the same body mass, but just a different body weight. Mass is how much matter is in something, and weight is the measure of the gravitational pull on you. So that is how you can weigh a lot if you are taller. You're not fat, you just have a strong gravitational pull.
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Gravity is one of the universal forces of nature. It is an attractive force between all things. The gravitational force between two objects depends on their masses, which is why we can really only see gravity in action when at least one of the objects is very large (like the Earth).\n\nIsaac Newton was the first scientist to define gravity using math. There will be a larger pull due to gravity if the objects' masses are larger and if the objects are closer together.\n\nOne thing we can do with Newton’s law is calculate an escape velocity for the Earth. That is the speed something has to go for it to escape the gravity of Earth. This number for Earth is about 11 km/s. This means that if you could throw a baseball at 11 km/s, it would never come down!