Monday, December 13, 2010

In relativity, light moves along with the rocket

Let’s take a standard illustration from relativity. We have two mirrors stationed on opposite walls of the interior cabin of a spaceship, and a light pulse bounces back and forth between these two mirrors, constituting as it were a light clock. The standard schpiel is that an observer on the rocket sees the light beam traveling straight up and down, since he is not in motion relative to the mirrors, while an observer on the ground sees the light beam traveling in a diagonal path between the mirrors, slanted in the direction of the ship’s motion, due to the mirrors being in motion relative to the ground observer. From this, we are supposed to conclude that, from the viewpoint of the ground observer, time for the observer on the rocket is passing at a slower rate than for the observer on the ground, or vice versa, depending on which viewpoint you assume. This supposed difference in time measurements is due to the light taking a shorter path in one frame and a longer path in the other.
But the conclusions drawn from the above illustration are incorrect. The Doppler shift is hard evidence of this. If light actually behaved as in this standard illustration, traveling in a diagonal path from the viewpoint of a reference frame that is stationary relative to the source of the light, then there would be no Doppler shifting of light. In the above illustration, from the viewpoint of one reference frame, light is being carried forward with the motion of the ship. In other words, in the illustration, the behavior of the light is dependent on the motion of the source. But the Doppler shift shows us, and even relativity claims, that light is independent of its source. In the correct mirror illustration, the light, once emitted or reflected, would travel straight across the intervening space to the opposing mirror, independent of the ship. In fact, due to the forward motion of the ship, the light would hit the opposing mirror at a point slightly behind the emission or reflection point of the mirror it had just left, and just how far behind would of course depend upon the velocity of the ship. In fact, relativity recognizes this point in the general theory, using this fact to draw the connection between acceleration and gravity. Why does relativity correctly describe the behavior of light for the general theory, while incorrectly describing it for the special theory? The difference is acceleration, obviously. But acceleration does not alter the behavior of light. The general theory has it correct. In the illustration of the light clock: for a ship not undergoing acceleration, the light bouncing between the mirrors will simply drift rearward at a constant, steady rate, while in a ship undergoing acceleration, the light will drift backward at an ever-increasing rate. In other words, in uniform motion, the point at which the light is reflected from each mirror will drift backward, with an equal spacing between the points on the wall where the reflection occurs; while in acceleration, the point at which the light is reflected from each mirror will drift backward, with a spacing between the reflection points that increases with each reflection. I am of course using a single pulse of light that, once emitted, continues bouncing indefinitely between the mirrors, rather than a steady stream of light pouring from an emitter. In the case of a steady stream of light, each successive pulse will hit the opposite wall at the same point, still slightly rearward of the emission point. Ether we use a single photon or a steady stream doesn’t alter my point or the physics of it. This “rearward drift” is just more visible if you confine the illustration to a single photon.
Relativity is riddled with these types of inconsistencies, such as the one above, between the special theory and the general.
If you believe this is not inconsistent, and I’m just a nutty crackpot, think about the Doppler effect. Visually, when light is emitted from a moving source, the light waves look like a v-shaped funnel—a series of concentric circles, starting with a huge circle, with each interior circle slighter smaller and to the side of the larger, until at the apex of the v we have a tiny circle, which is the pulse just emitted from the source. If I’m not describing it well enough, look in any physics textbook on the Doppler Effect, or better yet, watch an animation. You’ll see that each circle expands in place where it was emitted while the source moves onward. The Doppler effect looks like this because each pulse, each circle, stays in place in space and grows larger, while the source moves away from it. A flash of light, a pulse, is represented by a single circle, expanding in place from where it was emitted. Need I say it a few more times? The light wave, or the sound wave, is stationary, while the source moves onward. Or, if you insist on relativity, the source is stationary and the pulse moves away. So the pulse, the flash, would hit the opposite wall of the spaceship at a point slightly behind the spot opposite its point of emission. There is no way around this conclusion. It is a hard physical fact. But in relativity’s view, the flash is carried along with the motion of the ship, so that it is stationary relative to the ship. You cannot dispute anything I’ve said here, about the Doppler effect or about relativity. If you do, you’re the crackpot who doesn’t truly understand physics, not me. Relativity claims the light is moving along with the ship, stationary relative to it. The assertion that a stationary observer will observe the light in the rocket as taking a diagonal path across the cabin, while an observer in the rocket will see the light going straight across the cabin, is a fallacious assertion! This is the method by which Einstein claims time dilation, but it’s a faulty claim. An observer in the rocket will see the light pulse drift slightly rearward inside his cabin, while an outside observer at rest relative to the light will see it travel a straight path. The observer at rest relative to the rocket will see the light at rest relative to himself, while the rocket’s observer will see the light moving away, relative to himself.
The generation of a light wave is like a rock dropped into the water behind a speeding boat. The rock is dropped, and boom, the wave spreads out from the point of impact. The point of impact and the spreading wave does not follow along behind the boat, picking up the momentum of the boat. The impact point stays in place, receding behind the boat, even as the wave’s edge expands outward toward the boat. If relativity’s interpretation is true, then the point of impact would move along behind the boat, remaining stationary relative to the boat. 

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