Einstein worked this out in 1915 but did not say what property of space allows this
203795
What Einstein developed in his General Theory of Relativity (published in 1915) was a totally new, mathematical description of gravity—one that linked space to time and mass to energy in a fundamentally geometrical fashion.  In other words, mass(-energy) shapes space(-time) instead of acting like a “force” in the traditional Newtownian sense.\n\nThus, in Newton’s description of gravity, one would say that all bodies exert an attractive gravitational force on one another.  In Einstein’s conception, one would say that all bodies change the underlying geometry of space (and time) in a way that causes them to be attracted to one another.\n\nWhat’s a little odd about this is that it’s a fundamental property of space(-time) in Einstein’s General Theory of Relativity that it is “warped” by the presence of mass(-energy).  So the answer to your question sounds a bit like an answer by fiat:  a gravitating body warps space because that’s what gravitating bodies do.\n\nThe caveat is that curvature or warping really only provides an analogy to what the equations tell us.  If you want to imagine the effects of an object on its surrouning space(-time), then you can think of it as changing the shape of space(-time) in its vicinity.  The distortion is real—we can measure its effects—but the images that are often presented (of flexible sheets of space-time with bowling balls or marbles rolling around on them) simply present analogous situations.\n\n\nRyan Wyatt\nRose Center for Earth & Space\nNew York, New York
252571
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.
9361
There isn't an easy explanation, though it isn't that hard either.  \n\nThe whole idea of special relativity is that all motion is relative to the speed of light and that nothing with mass can travel that speed.  So, in answer to your first two questions, the speed of the light in both directions is still the same as it would be if you were standining still.  \n\nWhat Einstein proved was that there are no fixed points in space, but that space and time are constantly streching and contracting to accomodate the fixed speed of light.  The important thing to understand is that distances of space and lengths of time are different depending upon your relative motion.  I hope that begins to answer your question.
642337
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!
157679
Simple..\n\nU know why Einstein is so-called the most genius man in the world.\nEveryone who didn't study modern physic would say. the famous equation E=mc^2 bought his fame. No Einstein is genius becoz of his work on relativity.\nOne of the postulates made by the Einstein is that gravitational force is the curvature of space-time. U probably don't realize the importance of that statement. \n\nBut here i want to stress on the word space-time. Before Einstein, every scientists treat space and time as 2 separate distinct. But Einstein is genius enough to find that space and time as single entity. \n\nthe universe is all about energy and gravitational force.\nPeople says the universe start when a dense material exploded. Thus the universe was born. Remember to treat space-time as single thing. So, when universe was born, so the space and time was expanded and run. when there is no time, there is no space. so when the universe perish, the time also disappears and so the space...\nBcoz there is no mass, lead to no gravitational force and lead to no space and time.\n\n\nSo, God is really Almighty. there is no start and there is no end to Him
590909
GOOD QUESTION: well done! There is not really any such thing as time, it is merely our way of describing a particular abstract concept. If it was a solid physical reality it surely couldn't be relative. Lets all go and read Einstein and try to figure it out!
247571
Einsteins theory was that space turned back on itself, like a figure eight.
17792
Well\nrelativity \n\nPhysical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference. One consequence of the theory is that space and time are no longer viewed as separate, independent entities but rather are seen to form a four-dimensional continuum called space-time. Full comprehension of the mathematical formulation of the theory can be attained only through a study of certain branches of mathematics, e.g., tensor calculus. Both the special and general theories have been established and accepted into the structure of physics. Einstein also sought unsuccessfully for many years to incorporate the theory into a unified field theory valid also for subatomic and electromagnetic phenomena.\n\nEvolution from Classical Theory\n\nThe modern theory is an extension of the simpler Galilean or Newtonian concept of relativity, which holds that the laws of mechanics are the same in one system as in another system in uniform motion relative to it. Thus, it is impossible to detect the motion of a system by measurements made within the system, and such motion can be observed only in relation to other systems in uniform motion. The older concept of relativity assumes that space and time are correctly measured separately and regards them as absolute and independent realities. The system of relativity and mechanics of Galileo and Newton is perfectly self-consistent, but the addition of Maxwell's theory of electricity and magnetism to the system leads to fundamental theoretical difficulties related to the problem of absolute motion.
260357
What Einstein developed in his General Theory of Relativity (published in 1916) was a totally new, mathematical description of gravity—one that linked space to time and mass to energy in a fundamentally geometrical fashion. In other words, mass(-energy) shapes space(-time) instead of acting like a “force” in the traditional Newtownian sense.  The equations are sometimes collectively referred to as “Einstein’s Field Equations.”\n\nSo…  In Newton’s description of gravity, one would say that all bodies exert an attractive gravitational force on one another. In Einstein’s conception, one would say that all bodies change the underlying geometry of space (and time) in a way that causes them to be attracted to one another.\n\nThus, a gravitational “field” in that sense is the manner in which gravity affects the shape of space.  One often hears that space is “warped” by the presence of mass(-energy). \n\nThe caveat is that curvature or warping really only provides an analogy to what the equations tell us. If you want to imagine the effects of an object on its surrouning space(-time), then you can think of it as changing the shape of space(-time) in its vicinity. The distortion is real—we can measure its effects—but the images that are often presented (of flexible sheets of space-time with bowling balls or marbles rolling around on them) simply present analogous situations.\n\nWhew!  With all that said, I’d also point out that other fields—notably electric and magnetic fields—can also exist in space.  These have very different properties from a gravitational field, but they are affected by gravity in that gravity affects the underlying geometry of space(-time).\n\n\nRyan Wyatt\nRose Center for Earth & Space\nNew York, New York
521944
Doesn't that have something to do with Einstein's e=mc^2?  It sure looks like it.  The rest of seems to be an example of an explanation of the inefficiency of practical mass to energy conversions.  I could be wrong.\n\nOh, by the way:  what are you asking?
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Einstein’s Special Theory of Relativity started with two postulates: 1) that the laws of physics are observed to be the same in any non-accelerated reference frame and 2) that the speed of light (c) is observed to be the same for all observers.\n\nThe first assumption isn’t too worrisome, but the second seems trickier.  It’s certaonly not intuitively obvious, but it makes sense from both a theoretical and an observational perspective.  Observational because the Michelson-Morley experiment (and others) detected no change in the velocity of light when measured from a moving frame of reference; theoretical because Maxwell’s Equations yield a specific value for the velocity of light.\n\nWhen Einstein considered Maxwell’s Equations, he realized that they don’t allow for a “standing wave” solution, which is what a light wave would look like if you were travelling at the speed of light.  So he already sensed there would be a problem with travelling at very high speeds.  Indeed, when you re-work the addition of velocities, it comes out to be not simple addition, but a fraction that never gets larger than c.  \n\nThus, in the photon-photon collision you describe, each photon would “see” the other one travelling toward it with a velocity c.  (Although measuring velocities from a photon’s perspective is a little non-intuitive; you have to take the limit of the aforementioned addition formula, which causes some trepidation.)\n\nOh, and the ten-dimensional idea is just one among many…  No way yet to prove (or disprove) that one.\n\n\nRyan Wyatt\nRose Center for Earth & Space\nNew York, New York
325443
Yeah a doctor could answer that Einstein!
126699
Simple Relativity\n\nAlbert Einstein's 1905 paper "On the Electrodynamics of Moving Bodies" introduced the special theory of relativity. Special relativity considers that observers in inertial reference frames, which are in uniform motion relative to one another, cannot perform any experiment to determine which one of them is "stationary". This is known as the principle of relativity. While this principle was not new to Albert Einstein's work, he found that including electromagnetism in this principle required a new formalism with many surprising consequences. In particular, it required the speed of light in a vacuum to be the same for all these observers, regardless of their motion or the motion of the source of the light.\n\nOne of the strengths of special relativity is that it can be derived from only two premises (although Albert Einstein did not derive it this way):\n\nThe speed of light in a vacuum is constant (specifically, 299,792,458 meters per second). \nThe laws of physics are the same in any inertial frame of reference. This means that the laws of physics observed by a hypothetical observer traveling with a relativistic particle must be the same as those observed by an observer who is stationary in the laboratory. \n\nGeneral relativity\n\nGeneral relativity was developed by Einstein in the years 1911 - 1915. General relativity is a geometrical theory which postulates that the presence of mass and energy "curves" spacetime, and this curvature affects the path of free particles (and even the path of light). It uses the mathematics of differential geometry and tensors in order to describe gravitation without the use of the force of gravity. This theory considers all observers to be equivalent, not only those moving with uniform speed.
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Not sure if this is the answer your looking for but this is the answer to the twin paradox.  \n\nThere is really no paradox.  The crucial factor overlooked is that in order for the two twins to get back together and discuss their beliefs, one of them must accelerate.  In so doing, the accelerating twin does not remain in the same inertial frame, but rather ends up in a frame heading back toward Earth.  An observer always in an inertial frame will observe relativistic effects in the usual way--moving objects contracted and moving clocks running slowly-- even if the object or clock he observes accelerates.  In order for the twins to ever get back together one much TURN.  By definition when you turn you accelerat even if your speed remains constant.  Its the acceleration that prevents a paradox.\n\nAs to why Einstein only got one nobel prize, short answer none of the established physisist liked him.  He was just a patent clerk who was messing up their nice neat notions of the universe.
396662
Nobody really knows.  Einstein's special theory of relativity posits gravity as a warp of space-time caused by the object's mass, but that only pushes the question one layer further down.  All we know for sure is that gravity exists, is pervasive, and can be important.
9180
There are many ways to approach this problem. First, a quick and easy way:\n\nLet's agree that Alice is in frame A and Bob is in frame B.\n\nIf they both go on a trip and come back at the same time, as measured by Chuck who stayed home, then based on special relativity we can all agree that whomever was traveling closer to the speed of light on their trip will have a clock that's behind everyone else's (ignore accelerations for simplicity). So, if Alice traveled faster then her clock would be behind even Bob's clock. Based on this you must logically conclude that Alice would have observed Bob's clock ticking FASTER, not slower THAN HER OWN if she somehow viewed him in transit. Of course, Chuck would have seen both their clocks running slowly, but Alice's more slowly than Bob's.\n\nSome things are relative but you have some invariants, namely spacetime and the speed of light. Even if observers don't agree when things happened, the events are still fixed, in one position in spacetime. Einstein said that individually space and time are relative but you still have an absolute from which to measure, and that's spacetime. All entities are moving through spacetime at the speed of light (c). That's right, even you, but most of that velocity is directed through time. If an object were to have a zero velocity in space then its speed through time (the 4th dimension) is c. As you increase your speed through space some of your speed through time is diverted (but the vector total is always c) and thus time appears to slow down for you as observed by someone at rest in space.\nThe point being that there IS an absolute from which to measure so if Bob were traveling slower than Alice then Alice would see Bob's clock ticking faster than hers but slower than the stationary clock.\n\nI didn't quote any sources but most of my current conception of relativity came from an excellent book: "The Fabric of the Cosmos" by Brian Greene.
246450
It does contradict Einstein's notions of locality. Yet laboratory experiments have demonstrated the non-locality of particle entanglement. The philosophical implication is that another dimension, call it hyperspace, transcends ordinary space. The universe is a single hyperparticle.