If you look at the equations which are at the core of Einstein's theories of relativity, you find that as you approach the speed of light, your spatial dimension in the forward direction shrinks down to nothing and your clock slows to a stop.
A reference frame with zero width and with no progression in time is really a reference frame that does not exist. Therefore, this tells us that nothing can ever go faster than the speed of light, for the simple reason that space and time do not actually exist beyond this point.
Because the concept of "speed" requires measuring a certain amount of distance traveled in space during a certain period of time, the concept of speed does not even physically exist beyond the speed of light. In fact, the phrase "faster than light" is physically meaningless. It's like saying "darker than black. You might say that maybe Einstein's theories of relativity are wrong.
However, there is so much evidence now supporting relativity that, if it is wrong, it will have to be wrong in a small way that does not change these basic principles.
Learn more about untangling how Quantum Mechanics works. Spacetime is a crucial concept to answer why objects cannot move faster than light. Let us use co-ordinate geometry to mark an arrow for velocity with end of the arrow at the origin. If the arrow can be rotated, we get different projections on the x and y axis.
Hence, the object is always moving at a constant speed of v. It can move either entirely north or entirely east or toward north east at a speed that will never exceed v. The next step would be to replace the x and y axis of the algebra above with space and time respectively. Now, start rotating the velocity arrow under the assumption that all objects move at the speed of light in spacetime. Suppose the velocity arrow is pointing entirely in the time direction, it means that the object will move entirely through time and not through space.
Next, rotate the arrow toward the horizontal space direction and as the object is rotated closer and closer to the horizontal axis, the higher and higher is the velocity through space. At the same time, we have less and less velocity in time. When the arrow is pointing horizontally, the velocity is entirely through space.
All of the speed is through space. This analogy also illustrates that an object moving extremely fast through space moves very slowly through time. Hence, an object moving at the speed of light through space experiences no time at all or in other words is frozen in time.
And this is a more accurate reason than the reasoning of changing masses. On the train, meanwhile, the game-player will notice nothing different. Your two values for the speed of the ball will be different; both correct for your frames of reference. Replace the ball with light and this calculation goes awry. If the person on the train were shining a light at the opposite wall and measured the speed of the particles of light photons , you and the passenger would both find that the photons had the same speed at all times.
In all cases, the speed of the photons would stay at just under , kilometres per second, as Maxwell's equations say they should. Einstein took this idea — the invariance of the speed of light — as one of his two postulates for the special theory of relativity. The other postulate was that the laws of physics are the same wherever you are, whether on an plane or standing on a country road.
But to keep the speed of light constant at all times and for all observers, in special relativity, space and time become stretchy and variable. Time is not absolute, for example. A moving clock ticks more slowly than a stationary one.
Travel at the speed of light and, theoretically, the clock would stop altogether. How much the time dilates can be calculated by the two equations above. In our example above, this would be the person in the train. In this expression, c is a constant equal to the speed of light in a vacuum. The length of moving objects also shrink in the direction in which they move. Get to the speed of light not really possible, but imagine if you could for a moment and the object's length would shrink to zero.
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