Reciprocity in Relativity

In an earlier writing, I laid out a summary of The Facts according to relativity. Here they are again for reference:

The following is a summation of how two observers in motion at near light speed relative to each other view the situation, according to relativity. I call these The Facts.

From Observer A’s viewpoint:

• Observer B is in motion.
• Observer B is experiencing time dilation.
• Everything in Observer B’s reference frame (stationary relative to B) is length-contracted, as measured against a yardstick in my reference frame.
• We both measure the same speed for light.

From Observer B’s viewpoint:

• Observer A is in motion.
• Observer A is experiencing time dilation.
• Everything in Observer A’s reference frame (stationary relative to A) is length-contracted, as measured against a yardstick in my reference frame.
• We both measure the same speed for light. 

In the past, The Facts have led me to berate relativity, since it makes the prediction that two biological twins will each age more slowly than the other.

But let me reconsider The Facts. Basically, The Facts have each observer saying, “Everything is normal from my viewpoint, but I believe that everything is not normal from viewpoint of the other observer.”

Each observer reports that physically, everything is normal within his reference frame. He also expresses his belief that everything is not normal for the other observer.

Do you see what’s wrong with this picture? Each observer gives a description of his current experience of the natural world, as well as a description of what he believes to be the other observer’s current experience of the world.

Do you see it yet?

It does not matter what one observer believes about the other observer’s experience of the world. All that matters is each observer’s own experience. Both observers report that everything is normal in their reference frame. It’s completely irrelevant what each observer believes about the other’s reference frame! Both observers have firsthand experience that their world is normal. They have no experience of the other observer’s reference frame.

In the case of science, reality must trump belief, whether that belief is based upon logic or upon mathematical calculations. In other words, it is indeed a fact that both observers believe that the other is experiencing time dilation and other effects of motion. But if it is a fact that I believe Santa Claus exists, the fact that I believe in Santa Claus does not make Santa Claus exist. There is thus actually no conflict generated by The Facts, since we are free to discount the beliefs of each observer as to what the other is experiencing. The seeming paradox that The Facts predict that each biological twin will age more slowly than the other is due to a mere conflict of beliefs, a conflict that is resolved by allowing physical reality to trump beliefs about physical reality.

Both observers report that everything is normal. Therefore, everything MUST BE NORMAL in both reference frames! This is why, despite The Facts, both observers in my muon thought experiment in a previous writing report that their muons have decayed, in conflict with each observer’s expectation that the other observer’s muons should still be alive when they exchange their reports, which led me to discount the existence of time dilation when two observers are in relative uniform motion.

However, despite the preceding, there is experimental evidence that time dilation exists in the case of cosmic-ray muons when compared to their Earth-bound counterparts.

Taking this experimental fact together with my demonstration that time dilation is logically ruled out in the case of relative motion at constant velocity, it would appear that time dilation only exists within a gravitational field, or when an object undergoes acceleration. In all other situations, time dilation ceases to be a consideration, as it does not exist.

In light of this, one must wonder how Einstein came to theorize the existence of time dilation, since acceleration was excluded from the special theory. After all, according to relativity, time dilation is a consequence of the constancy of the speed of light. But if it’s shown that time dilation does not exist in cases of uniform relative motion, then light speed should not be constant. It need only be constant for all observers undergoing acceleration or gravitation.

Of course, if light speed is not constant, then interferometer results once again become a problem. Unless you’re a Geocentrist.

But wait, you might object. If one of the observers, considering himself stationary, looks through a telescope at the other observer, he’ll see a clock on the other observer’s ship ticking more slowly. Therefore time dilation MUST exist.

My response: not really. Because depending on whether the other ship is approaching or receding when our observer looks through his telescope, he’ll see the other clock either ticking faster or slower. Do you really think the rate at which time passes depends upon the direction of the other ship’s travel? The Doppler Effect doesn’t tell us about time dilation. It tells us whether the ship is approaching or receding.

Yes, you object, but the time dilation is in addition to the Doppler Effect.

My response: Okay, fine. The rate at which time is passing depends upon which direction the ship is traveling. Throw a new complication into relativity if you want to. And then YOU try to explain why time dilation should depend upon direction of travel.

You could further protest that The Facts as I’ve formulated them presuppose my conclusion because The Facts are written from a subjective viewpoint. You protest that it’s not a subjective belief of one observer whether or not the other observer is experiencing time dilation. There is an objective fact that whichever frame is regarded as being at rest, the other is time dilated and length contracted. It’s not a matter of belief; it’s a matter of reality.

But isn’t “objective” another way of saying “absolute”? Isn’t bringing objectivity into relativity forbidden by relativity? Relativity involves being able to move from one subjective viewpoint to another and find that all viewpoints are equal. There is nothing objective about it. Relativity is inherently subjective.

Besides, by trying to rephrase The Facts objectively, you will basically be saying that it is an objective fact that whichever frame subjectively regards itself as being at rest…It’s redundant, because relativity requires that you assume the subjective viewpoint of one particular frame, but that you’re not bound to remain in that frame. But you are always viewing things subjectively from one particular frame. So The Facts are not framed in such a way that they presuppose my conclusion. They’re framed in the only way allowed by relativity.