Walt Cuirle's Challenge

"Good science simply explained." If you're willing to give it a try, here's a pretty little piece of balderdash to practice on:

Warning! In what follows, I am speaking in the typical voice of the pseudoscientist, complete with exaggerations, half-truths, confabulations and outright lies. I know that. You don't have to write and tell me so.

Gravity waves and graviton particles are a fundamental and necessary postulate of general relativity. But they have never been detected. And they never will be detected for a simple reason: the theory requires that gravity's mediator -- be it gravity waves or graviton particles -- must propagate at light speed. Simple experiments can demonstrate that gravity cannot be limited by light speed. General relativity has become hopelessly complex because it is fundamentally flawed: gravity either has no mediator or, if it does, that mediator travels at many millions of times light speed.

Forget theory and just try thinking of it in concrete terms. Suppose that the Sun disappeared, just went poof, ten seconds from (snap your fingers on my mark) now. How long would it take the Earth to feel the effect?

You might think the answer is about eight minutes since that's how long it takes light to travel to Earth from the Sun and these hypothetical gravitons travel at the speed of light. But that can't be right. Look at the equation for Newton's law of gravitation. It simply says that the force of gravitational attraction between two bodies is proportional to the product of their masses, inversely proportional to the square of the distance between them and along the line connecting their centers of mass. There is no mention of time in there at all.

Newton's law of gravitation is pretty well demonstrated: we've used it for three hundred years to time falling apples, compute ballistics, fly spaceships and find planets. Works every time. General relativity, on the other hand, has no experimental evidence dealing with its predictions of the mechanism of gravitational propagation. When Laplace, in his Celestial Mechanics, tried to introduce an explicit propagation term he found that all those wonderful Newtonian predictions went out the window. The Solar System just fell apart. To make it come back together again, he had to give gravity a propagation speed many millions of times the speed of light.

But you don't need to read Laplace, or even Newton, to grasp the idea. Just think about it for a minute. The Sun is not, as we all know, the center of the Universe. It's moving. If it's also spitting out these finite-speed gravitons while it's moving, the effect ought to be like a lawn sprinkler on roller skates: the line of the gravitational force between the moving Sun and Earth ought to be offset a little bit, pointing at where the Sun was when the gravitons or whatever were emitted and not at where the Sun is when the gravitons hit. But if we go out and measure it, we find that the line of gravitational force is not offset. It's right along the centers between the two bodies, just like Newton said it would be.

Well, okay, the angle is small and eight minutes might not be significant. Maybe, to be fair, we should try something else.

This effect, if it exists, must get more noticeable as we get farther from the Sun. So picture Pluto, almost six billion kilometers -- that's around six light hours -- away. That's a lot longer than just eight minutes so you can't argue that the time is insignificant. If gravity really traveled at the speed of light, then in order for Pluto to stay in its orbit the way it does the Sun would somehow have to know where Pluto will be almost six hours from now and adjust the direction of its graviton emissions accordingly. Common sense says that can't be so and it isn't -- go out and measure it and the vectors still line up as Newton predicted.

It doesn't help to invoke Einstein's curved space either; that just changes the terminology. The Sun is still moving, curved space or not. If you buy into Einstein, then somehow the moving Sun is telling the bit of space six hours ahead of Pluto how to curve so that all the vectors line up correctly by the time the Sun gets into position. Einstein was right about a lot of things; for example, the speed of light really is a constant for all observers and special relativity really does work the way he said it does, with slowing clocks and shrinking meter sticks and all that. There's experimental evidence for it all. But he never did say that the speed of light is a universal speed limit and he's not the guy that made up gravitons.

No matter how you cut it, if you assume light-speed propagation time for gravity you get ridiculous conclusions.

So Occam's razor is still sharp and the old-timers were right. If the Sun went poof, Earth would fly off immediately because gravity is not limited to light speed. And if gravity can travel faster than light, well, then, who is to say that something else can't?

There you have it in a nutshell. I've left out the sly asides about the Establishment, the deification of Galileo and the genuflections toward his prophet Tesla that are inevitably sprinkled throughout such writings. The memories of Galileo and Tesla don't deserve further distortion; besides, you've seen all that before.

Now here's the game. Explain what's wrong with the above argument. To make it interesting, let's follow one common condition imposed by the pseudoscientists: cite experimental evidence or at least reasonable gedanken experiments and try to stay within the context of the real scientists that the pseudoscientist cites. In this case, those would be Galileo, Newton, and Einstein, although in Einstein's case we are only allowed to use special relativity as accepted fact.

The audience for the explanation is Galileo's Simplicio: an honestly open-minded, non-credulous but relatively uninformed listener. The goal is to explain the truth of the matter so transparently that Simplicio feels "Ah ha!" and "Oh, wow!" at the same time. Don't just take away the mystery: bring back the wonder, too.

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