Why is gravity a theory and not a law?
103297
Theories are more complex than laws, where laws describe only one action or phenomena, theories explain the mechanisms behind the phenomena and related phenomena. \n\nAn example of a law is the Second Law of Thermodynamics, which states:\nThe total entropy of any thermodynamically isolated system tends to increase over time, approaching a maximum value.  \n\nThe theory of gravity, on the other hand, governs everything from falling bodies, forces of attraction between bodies, and planetary motion.  It describes a wide range of phenomena, and is far more detailed than the Second Law of Thermodynamics.  \n\nTheories are also mutable and evolve as better information becomes available.  The Second Law of Thermodynamics will not and does not change, but gravity theory is evolving as discoveries are made in the field of quantum mechanics.\n\nI found this on a website; it may be helpful in describing the difference between theory and law:\nAn analogy can be made using a slingshot and an automobile. \n\nA scientific law is like a slingshot. A slingshot has but one moving part--the rubber band. If you put a rock in it and draw it back, the rock will fly out at a predictable speed, depending upon the distance the band is drawn back. \n\nAn automobile has many moving parts, all working in unison to perform the chore of transporting someone from one point to another point. An automobile is a complex piece of machinery. Sometimes, improvements are made to one or more component parts. A new set of spark plugs that are composed of a better alloy that can withstand heat better, for example, might replace the existing set. But the function of the automobile as a whole remains unchanged. \n\nA theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole. \n(Comes from the first site listed in Sources)\n\nHope this is helpful :-)
961254
No because when they do they become scientific LAWS\n\ne.g. the Law of Gravity
418600
That's a mystery that the physicists haven't figured out.  \n\nAristotle theorized that the objects "want" to go toward the middle of the earth.  We might laugh, but think he has a point.  A common theme throughout reality is that things want to go toward equilibrium, and if you keep wanting to go toward something, or have a pull toward something, then you aren't at equilibrium.\n\nPhysicists theorize about gravitons, particles that are gravity.  I think that's wrong.  I believe that gravity is working on the stuff that space is made of.  I believe that the natural state of the universe is probably a singularity.  And when it's not in this state, it tries to return to this state.
113961
Simple explanation:\n- - - - - - - - - - - -\n\nThere are four fundamental forces that act on objects:\n\nGravity\nElectromagnetism\nWeak (responsible for radioactive decay)\nStrong (holds the nucleus together)\n\nFrom Newton's 2nd law, a force F= m a where m is the mass of the object and a is its acceleration (acceleration describes how an object changes speed, so it has to do with movement of the object). \n\nGravity is one of the 4 possible choices for F. So when the force of gravity exists, things accelerate, according to Newton's 2nd law. \n\nDeeper Exploration:\n- - - - - - - - - - - - - \n\nOne can ask the question, but WHY does gravity create a force? Einstein described it in the general theory of relativity as a bending of the space we live in (called spacetime: 3 space dimensions and one time dimension), and then specified that objects are required to take the shortest path in this curved space. \n\nHowever, that still does not describe WHY gravity does this. Current belief (but not yet proved) is that two objects with mass exchange messenger particles called gravitons (not yet observed) that communicate the force of gravity between then (electromagnetism has photons, or light as messenger particles, weak and strong forces also have messenger particles, so people think that gravity should as well). \n\nAnother interesting thread of thought in physics is that all 4 of the four fundamental forces are aspects of the same thing (just like electricity and magnetism are aspects of the same thing). So far, weak forces and electromagnetism have been shown to have the same origin when looked at in the right way, and it is possible that the strong force has the same origin as well (called a Grand Unified Theory, or GUT). Physicists are trying to find a framework whereby all 4 forces are aspects of the same universal force (called a Theory of Everything, or TOE).\n\nHowever, one can still ask, why is it this way? Well, although we have a few theories here and there, very little is proven, and the basic bottom line is, we do not know WHY gravity makes things move. \n\nBut we have a lot of clues and equations and we can make very accurate predictions for how gravity works in many cases.
510535
Yes gravity is a theory. So it should be taught to children along side the other legitamate theory of Human Flight Ability or HFA. You should test this theory of Human flight from your nearest building. Teaching that gravity is a theory and Human Flight Ability is an equal theory has the same effect on our children as teaching Evolution and Intelligent Design. It confuses them into not understanding the difference between reality and fantasy. It's very dangerous. And also explains why the U.S. is trailing 7 other countries in Science Education despite being the most well financed country in the world.
998030
i think it is a theory of physics that doesn't exist yet but is the ultimate goal of physicists. the problem is that rules of physics don't apply to all things.. like there is the regular everyday physics like Newton's gravity, cause & effect, etc. then Einstein figured out relativity and added time as a factor to the picture. so physical properties of a thing in the universe depends on the perspective of the observer. if something (thing 'a') is moving it changes the way it acts in relation to thing 'b', which isn't moving, or is moving faster or slower... 'relative' rules. even einstein got upset though, when people were able to look at tiny things, subatomic particles, and found they didn't act according to the rules of the big world. they had their own rules of interaction. rules of science should apply to all things, or they aren't really very good at explaining the world, so einstein and every scientist since has been looking for a theory of physics that 'unifies' the universe; both big and small. a set of rules of physics that you can say, yes that's what will happen if  this happens, either to a person or a subatomic particle. this all gets mushed up in the idea that understanding the universal rules will give us an idea of how the universe began..like the first seconds of the universe which is another obsession for scientists. so that's why it's called the grand unification theory. it would unify all the theories into one that applies all the time to all things. but it doesn't exist yet. look up stuff on stephen hawkings theories and maybe string theory for some neat ideas
299832
gravity aint got nothing to do with it
79989
Still more theory than fact.\nIt is responsible for the force of gravity.
1068102
Gravity may only be a theory, but we have a good idea that it is real. We may not know the exact workings of gravity, but we know it is there.\n\nGravity affects everything. It affects all the planets, it's what makes us revolve around the sun. I'm sure the 'devil' has nothing to do with making sure all the planets get around the sun. It's trivial, and you're theory is even worse than the theory of gravity because it has absolutely no backing. We can see gravity and it's effects everyday. Scientists don't know all about it, but for the most part, we know it's real. Your theory on the other hand, there is no proof of the devil. He's a made up character, fake. Then to say he pulls us down, you forgot to take into consideration everything else effected by gravity, not just humans. \n\nIf the devil is pulling us down so effectively, he must be extremely strong. Where is your God to pull us up? Shouldn't He be able to pull us up, if He is so great? Nope, still not happening.\n\nTheory disproved. Face it, religion plays no part in science. Religion's purpose is to make people feel good about themselves, and provide answers to the answerless (such as creation). Science is out to prove what happened, and religion serves as a temporary explanation for most.
937989
Gravitons are theoretical "virtual particles"...it is an attempt that quantum mechanics makes to explain gravity...but general relativity with its curve in spacetime explains it much better.
904548
A law has been proven and can never be broken. It can be bent but not broken. A theory is an idea that suphices for the phenomena at hand. it would be the most logical of explanations to date until another theory which may be more precise is thought up. Theories cannot normally be tested because they sometimes have to do with concepts that cannot be tested without super enhanced technology.
409964
All (good) science is based on theoretical notions thought up by someone carefully observing the universe around them, proposing an explanation, and then testing to see if it can be used to predict a likely outcome.  If it predicts the likely outcome all the time, it becomes a Law.  In physics, Gravity is already a Law, but String Theory is still a theory.  A theory is not pseudoscience unless most thoughtful people can see holes in it.  Theoretical thought, even "on the margins of science" is essential for progress.\n\nDoubtless there were many sensible folk who thought the Wright brothers were lunatics, but they had the math & mechanical skills to prove their theoretical notion that a machine could make a man able to fly.\n\nNow go to your workshop and think!
64226
Whoa!  These are very different questions, but here is Joule's law is a physical law expressing the relationship between the heat generated by, and the current flowing in, a conductor. It is named for James Prescott Joule who studied the phenomenon in the 1840s.  As for The Theory of Everything, it is a hypothetical theory which would unify all known phenomenon and make them explainable. The Grand Unified Theory.  In the universe, there are 4 fundamental forces. The Weak, the Strong, the Electro-Magnetic and the Gravitational.  However, gravity does not 'fit in' with the other forces (in that it does not appear to exist at very small scales).  If this is the case, then why?  We believe that there is a theory so complete that it can do everything from explain the aparent randomness of quantum phenomenon (for example an apparent lack of causality) all the way up to the orderings of filaments and other grand structures.  String Theory is one of many 'Theories of Everything' which is being explored.  There are many different flavors of string theory, but most of them agree on the fact the our universe has more than 4 dimensions and some suggest as many as 10 or more.  Further, the theory suggests that all matter and energy is composed of tiny 'strings', which vibrate.  The type of vibration determines what type of fundamental particle the string is.  In theory there would be a 'vibration' representing a gravity particle (the graviton), but as of yet no particles resembling gravitons have been seen to exist.  On a less scientific note, many Theories of Everything have the fall back that they do not allow for testable, quantifiable and observable results - the core of modern science - and thus fall within the realm of philosophy in that they attempt to explain the way things are, yet leave specific details lacking.
97749
There is no such thing as LAW OF SUPPLY AND DEMAND -- comparably to the LAW OF GRAVITATION (or Newton's Law) ... it is all being intercepted by governments and political parties.\n\nThese institutions are always thinking of their own "self-interest".
540592
Gravity is not caused by magnets. It is caused by matter itself, but it only happens noticably when theres a LOT of matter together (the earth is a LOT of matter).\n\nWe dont really know why matter causes gravity. We cant even measure gravity waves, but we're trying.\n\nString theory is a mathematical system which tries to explain gravity. I dont understand any of it, but thats what people who want to understand gravity are studying.
834129
You are confusing energy and gravitational force. The two are\nnot equivalent. The property of gravity is based upon the mass of an object, the more mass an object has, the more gravity it posesses. The amount of gravity an object has does not increase or decrease with time.
456434
look at Newton for example.  He may not have had a complete theory, but a lot of it is still valid.  \n\nNewton has been modified by einstein. but this is only in the case of very very massive objects (the size of the sun) and very fast moving objects (.7 c and up or 10^8 m/s, very very very fast).  \n\nBut we do not encouter those things in day to day life... infact you will only encounter that limit in stellar physics and particle physics.  \n\nWhen you build a rocket and launch it you are using purely newtonian mechanics.  \n\nThere have been methodes discoverd that make the calculations easier in many situaitions, but for most situations you will use newtons force laws instead of, say, the lagragian equations of motion.  \n\nThis is the same is all well developed feilds.  \n\n\nAlso a bunch of these non symplified theorys that are technecly correct are just too difficlut for just any one to understand.  If you wish to use lagrages or hamoltons equations of motions you need to know differntial calculus.  and you need to be rather good at it.  on the other hand you can do newton with elementry calculus, or even just algebra.  \n\nAlso just the concepts are difficlult to understand.  We can all imagine electrons traveling around the neucleus like planents around the sun, but it is much more difficlt to explain that electrons are not particals but they are waves and they tend to exist in a reigion of space moving around, but because they exist every where they have no change in momentum, and for this reason they exist with out giving off radiation.  \nBut once you understand the first theory, then you can start to modify the picture and try to understand the way things really are.  Which is actualy impossible because the particals exist in a dimention that we can not see, and act in a way that we can not understand.