What is the theory of relativity?  Explain it.?
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Relativity consists of two parts, namely Special and General Relativity.\n\nSpecial Relativity : Two postulates\n\nPostulate 1. The Principle of Relativity\nThe laws of physics are the same in all inertial frames of reference.\n\nNo coordinate system which is in absolute rest. All motion with constant speed is relative and any coordinate system moving with constant speed (relative to the "fixed stars") is called an inertial coordinate system (or inertial frame [of reference]). \nTwo inertial frames A and B are moving with constant speed  relative to each other. An observer at rest in A will say that objects at rest in B are moving with respect to A. On the other hand, an observer at rest in B will say that it is the objects at rest in A that are moving with respect to B. Motion is relative!\n\nPostulate 2. The Constancy of Speed of Light in Vacuum\nThe speed of light in vacuum has the same value c in all inertial frames of reference.\n\nSimultaneity \n    One of the most important concepts in special relativity is the one of simultaneity. Two physical events that occur simultaneously in one inertial frame are only simultaneous in any other inertial frame if they occur at the same time and at the same place. Time is relative!\n\n\nGeneral Relativity\n\nIn short, it is a theory in which gravity is described by saying that space and time are dynamics quantities that can curve in response to the effects of matter and can in turn alter the behavior of matter.
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It's called relativity because it shows that time and space are relative to the observer, and can be perceived differently from other reference frames. \n\nWhat's this about collisions?
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The general theory of relativity is much more complex and difficult to understand than the special theory. It proves the force of Gravitation, as proved by Sir Isaac Newton, wrong. According to Newton, gravity was a force between two bodies, which depends on their respective mass and the distance between them. \nThe basic idea of general relativity can be illustrated with the help of an imaginary experiment as performed by Einstein.  Suppose a lift is at rest in space.  If a ball is released within the lift, it will float in space and not fall.  If the lift accelerates upward, an observer within the lift will see the ball fall to the floor exactly as it would under the pull of gravity.  The ball appears to fall because the floor of the lift, as seen from outside the lift, it accelerates upward toward the ball.  All the effects we associate with gravity would be seen by the observer in the lift.  Einstein called the phenomenon shown in this experiment the Principle of Equivalence. This principle states that it makes no difference whether an object is acted on by a gravitational force or is in an accelerated frame of reference.  The result in both cases will be the same.  From this principle, Einstein reasoned that matter in space distorts or "curves" the frame of reference of space. The result of this curvature is what we experience as gravity. The Euclidian or flat geometry was unable to explain the curve, so Einstein used geometries called Riemannian geometry to explain the effect. \nAccording to Newton's theory, a planet moves around the sun because of the gravitational force exerted by the sun.  According to the theory of general relativity, the planet chooses the shortest possible path throughout the four-dimensional space- time, which is deformed by the presence of the sun. This shortest possible path is called a geodesic.  This may be compared to the fact that a ship or an aeroplane crossing the ocean follows the section of a circle, rather than a straight line, in order to travel the shortest route between two points.  In the same way, a planet or light ray moves along the "shortest" line in its four-dimensional world. \nSo far, three things have been discovered in which Einstein's theory of general relativity receives experimental proof as opposed to the theories of Newton.  These differences are not great, but are measurable.  In the first place, according to Newton's theory, the planet Mercury moves in an ellipse about the sun.  According to Einstein's theory, Mercury moves along an ellipse, but at the same time the ellipse rotates very slowly in the direction of the planet's motion.  The ellipse will turn about forty-three seconds of an arc per century (a complete rotation contains 360 degrees of an arc and 360 X 60 X 60 seconds of an arc).  This effect is rather small, but it has been observed.  Mercury is nearest to the sun and the relativistic effect would be still smaller for other planets.  \nIf we take a picture of part of the heavens during an eclipse of the sun and near the eclipsed sun, and then take another picture of the same part of the heavens a little later, the two photographs will not show identical positions for all the stars.  This is so because, according to general relativity, a light ray sent by a star and passing near the rim of the sun is deflected from its original path because the sun's gravity curves space.  The effect of gravity on light is also the reason why black holes are invisible.  The gravitation in a black hole is so strong that light cannot escape from it. \nPhysicists have known for more than a hundred years that when some elements are heated to incandescence they give off a pattern of spectral lines (coloured lines), which can be examined through a spectroscope.  According to the Einstein theory, the wavelength of light emitted from a massive object will become longer because of gravitation.  This results in a shift of the spectral lin
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No.  The theory of relativity states that an object moving at a high enough velocity will appear to shrink along the direction of motion and increase mass from the point of view of a non moving observer, so much so that, if a physical object would be to travel at the speed of light, its dimension will be zero and its mass infinite.
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The equation E=MC2 is the derivation from Einstein's relativity theory. this is not a case of the classic mechanics. this equation explains the value of energy of an atom. \n\nE-> Energy\nM-> mass of the atom\nC-> speed of the light.\n\nin this only speed of the light is constant. the mass differs by frame to frame in accordance to theory of relativity. so the energy of the atoms also differs with frame to frame. but this equation is not fully correct and Lorentz had made corrections to it. \n\nAnybody who can prove this equation as a total wrong thing with strong evidences will be announced as the greatest of the universe..
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I think u could visit this website for the general relativity:\n\nhttp://archive.ncsa.uiuc.edu/Cyberia/NumRel/GenRelativity.html
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Well I would use examples and predictions. \n\nFirst I would say, there are TWO theories of relativity: the special theory, and the general theory. \n\nSpecial Theory\n--------------\n\nRather than go into an explanation of the why the speed of light is constant in all inertial frames, I would mention the predictions of the special theory. \n\n1. Nothing can go faster than the speed of light, which is like a speed limit for the universe. I think most children have seen speed limits, so this might seem familiar to them.  \n\n2. If you are in a space ship going very fast, close to the speed of light, time will slow down and you will age more slowly.\n\n3. If you are in a space ship going very fast, close to the speed of light, you will get shorter from front to back. You will become flattened like a pancake.\n\n4. If you are in a space ship going very fast, close to the speed of light, your mass will increase, so that if you were weighed you would be heavier. \n\nGeneral Theory\n---------------\n\nRather than talking about the curvature of space-time, I would again use the predictions of the general theory. \n\n1. When something is very heavy, it has a lot of gravity, and it can even pull on light. In this way, light can be bent. \n\n2. If the object is very heavy, the light is unable to get away at all, so we call the object a black hole. \n\nThis is good enough to start and whet their appetites. If they want more detail, there is a HUGE amount of material out there.
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Einstein's theories (never mind that they have checked out in reality) are incredible: space is curved; the shortest distance between two points is not a straight line; the universe is finite but unbounded; \n\nparallel lines eventually meet;
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Gravity is a term to explain a phenomenon. The theory of gravity is a theory to explain a fact. The pull between bodies(known as gravity) is a fact.\n\nWe can measure this pull with a good degree of accuricy since the days of newton. Yet untill this moment we don't have a complete explanation as to why gravity occurs!\n\nNewton didn't really explain gravity, he just offered methods to measure its effect. Modern physics describe gravity as a result of the bend in the fabric of space-time.More theories will develop later.\nThat's what science is about, offering explanations, then making them better with time, then even better and so on. There is no best of final explanation ever, but there are always better ones that could be used to make life easier.
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This has been answered many times. Use the search function to find out more information. \n\nThere are two relativities:\n1. special theory\n2. general theory\n\nThe special theory makes many predictions about things that move very fast:\n\n1. They get shorter, front to back.\n2. They gain mass\n3. Time slows down for them\n\nInformation cannot be transferred at a speed greater than the speed of light. \n\nGeneral relativity describes gravity as a bending of space. So gravity can bend light. And it also predicts something called a black hole, which light cannot escape, and is a place where the equations of physics break down.
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"Short Words to Explain Relativity"\n\nAlbert Einstein's Theory of Relativity\n\nIn Words of Four Letters or Less\n\nhttp://www.muppetlabs.com/~breadbox/txt/al.html
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String theory is just a theory.  It was made up to try to explain physical phenomena.  Scientists are still trying to prove or disprove it.\n\nThe infamous Einstein theory of relativity, is still that:  a theory.  It did not explain everything in the universe, either.
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it is a conception of Space, made not only of 3 dimension, but 4. The fourth is Time. The relativity equations are made in this 4 dimension Space-time "Space".\nThe idea was not from Einstein, but he was the one who hd spread it.
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Ask around if any of your friends have a GPS system.  There is your example of a daily-life example of the theory of relativity.  The Global Positioning System would not be able to give you very accurate locations if it did not take the corrections to time and distance from both special, and general reletivity into account.  I am pretty sure that it is the first piece of public consumer-grade equiptment that relies on our understanding of General Relativity.
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Direct translation is:\n"Energy released equals the mass lot times the speed of light squared."\n\nIt's a theoretical bridge that shows a way for energy to become matter and vice versa.\n\nIt means as objects approach the speed of light (theoretically the speed limit of the universe), they gain mass in a form of sublimated accretion.\n\nIt means that time should slow down as speed approaches the speed of light (approaching in terms of the mathematical concept of the limit).\n\nThere's a LOT of open possibilities. But it's still mostly a theory.\n\nOther theories have stemmed from it that sometimes support and sometimes rebuke the Special Theory of Relativity, as this is known. For instance, the Superstring Theory of Everything, Gravitational Mechanics, and the Unified Theory of Gravity, all borrow from Einstein.
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That would be Einstein's Special Theory of Relativity.\n\nhttp://science.howstuffworks.com/relativity3.htm
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You have the old Newtonian physics, which is called classical physics.  It is built on the premise that space and time are absolute fixed entities, and cannot change.  This is the physics that you learn in High School, and is true and works for our everyday life.\n\nHowever, when one begins to approach the speed of light, and apply the classical physics to that situation, we see violations of physical law: such as an object can go faster than the speed of light.  For example, let's say a car is traveling at half the speed of light, and you shoot a bullet that is traveling at .6 times the speed of light (all hypothetical of course).  An observer would see the bullet traveling at 1.1 times the speed of light, which is obtained by adding the speed of the car and the bullet together.  That is the classical method of finding the bullet's speed.\n\nEinstein correctly surmised that nothing can travel faster than the speed of light, or even be seen traveling faster than light, such as our bullet.  Therefore, he considered how classical physics would look if space and time were not fixed entities.  In doing so, he developed a more comprehensive physics, called relativistic physics, which fixes our bullet problem.  \n\nThe cool thing is, the relativistic equations are almost exactly the same as the classical equations, with one exception: the have what I call a relativistic adjustment.\n\nFor example, to find the bullet's speed as seen by an observer, requires the following equation:\n\nV = Vc + Vb\n\nWhich in our problem would be:\n\nV = .5c + .6c = 1.1c\n\nThe relativistic equation is almost the same:\n\nV = (Vc + Vb)/(1+Vc*Vb/c^2)\n\nThe numerator is the same as the classical equation.  The denominator is the relativistic adjustment.  So, the equation becomes with our example:\n\nV = (.5c + .6c)/(1 + .5c*.6c/c^2) = .846c\n\nThe bullet would be seen traveling at almost 85% the speed of light.  \n\nThe cool thing here is that when you use speeds that are very small, like everyday speeds, the relativistic adjustment bascially equals one, so it reduces to the classical equation.