# Thread: How does the Tiny Cosmic Ray create a "Gravity Well" or warp

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## How does the Tiny Cosmic Ray create a "Gravity Well" or warp

Here is a slightly different version of how this is 'supposedly' working...

http://galileoandeinstein.physics.vi.../srelwhat.html

Experimental Evidence for Time Dilation: Dying Muons
The first clear example of time dilation was provided over fifty years ago by an experiment detecting muons. (David H. Frisch and James A. Smith, Measurement of the Relativistic Time Dilation Using Muons, American Journal of Physics, 31, 342, 1963). These particles are produced at the outer edge of our atmosphere by incoming cosmic rays hitting the first traces of air. They are unstable particles, with a “half-life” of 1.5 microseconds (1.5 millionths of a second), which means that if at a given time you have 100 of them, 1.5 microseconds later you will have about 50, 1.5 microseconds after that 25, and so on. Anyway, they are constantly being produced many miles up, and there is a constant rain of them towards the surface of the earth, moving at very close to the speed of light. In 1941, a detector placed near the top of Mount Washington (at 6000 feet above sea level) measured about 570 muons per hour coming in. Now these muons are raining down from above, but dying as they fall, so if we move the detector to a lower altitude we expect it to detect fewer muons because a fraction of those that came down past the 6000 foot level will die before they get to a lower altitude detector. Approximating their speed by that of light, they are raining down at 186,300 miles per second, which turns out to be, conveniently, about 1,000 feet per microsecond. Thus they should reach the 4500 foot level 1.5 microseconds after passing the 6000 foot level, so, if half of them die off in 1.5 microseconds, as claimed above, we should only expect to register about 570/2 = 285 per hour with the same detector at this level. Dropping another 1500 feet, to the 3000 foot level, we expect about 280/2 = 140 per hour, at 1500 feet about 70 per hour, and at ground level about 35 per hour. (We have rounded off some figures a bit, but this is reasonably close to the expected value.)

To summarize: given the known rate at which these raining-down unstable muons decay, and given that 570 per hour hit a detector near the top of Mount Washington, we only expect about 35 per hour to survive down to sea level. In fact, when the detector was brought down to sea level, it detected about 400 per hour! How did they survive? The reason they didn’t decay is that in their frame of reference, much less time had passed. Their actual speed is about 0.994c, corresponding to a time dilation factor of about 9, so in the 6 microsecond trip from the top of Mount Washington to sea level, their clocks register only 6/9 = 0.67 microseconds. In this period of time, only about one-quarter of them decay.

What does this look like from the muon’s point of view? How do they manage to get so far in so little time? To them, Mount Washington and the earth’s surface are approaching at 0.994c, or about 1,000 feet per microsecond. But in the 0.67 microseconds it takes them to get to sea level, it would seem that to them sea level could only get 670 feet closer, so how could they travel the whole 6000 feet from the top of Mount Washington? The answer is the Fitzgerald contraction. To them, Mount Washington is squashed in a vertical direction (the direction of motion) by a factor of the same as the time dilation factor, which for the muons is about 9. So, to the muons, Mount Washington is only 670 feet high—this is why they can get down it so fast!
Why they are referring to this The answer is the Fitzgerald contraction rather than LT, I will leave it up to the Pro's to suss out.

But, I think the part in Red is the real ? mark, and leads automatically to ATM, and begs the question...IF time dilation is not "Real", then what would be the alternative explanation for the Cosmic Rays hitting the atmosphere and what is happening in those collisions. Nereid? Trinitree88?

ETA: I can put this in there....But, I think the part in Red is the real ? mark because...

I can ask the question... How does the Tiny Cosmic Ray, having that collision, create a "Gravity Well" or warp spacetime OR [insert proper wording] for the earth/mountain to fall into or follow the geodesics of curved space?

2. This post has been split off from this thread "some kind of twin paradox (now with muons)" as the basic question that seems to be asked (and if I am not mistaken has been answered several times already in various questions by RussT:

How does the Tiny Cosmic Ray, having that collision, create a "Gravity Well" or warp spacetime OR [insert proper wording] for the earth/mountain to fall into or follow the geodesics of curved space?

3. Originally Posted by RussT
I can ask the question... How does the Tiny Cosmic Ray, having that collision, create a "Gravity Well" or warp spacetime OR [insert proper wording] for the earth/mountain to fall into or follow the geodesics of curved space?
It doesn't cause a physical change in the mountain, its velocity just affects a difference in how the particle interacts with spacetime.

4. Did you read the text you quoted?

From our frame of reference, we are stationary and the muon is travelling very fast. Therefore as predicted by SR it will be time dilated and will not decay before hitting the ground. [2nd paragraph of quote]

Alternatively (and equivalently) from the muon's frame of reference, it is stationary, and the earth is moving very fast. Therefore as predicted by SR it will perceive the earth, and distance to it, as contracted. So the distance it has to travel is less. [3rd paragraph of quote]

These are two views of the same thing from different points of view. Note that from the muons frame of reference, time on earth would be dilated but that isn't relevant to this explanation.

IF time dilation is not "Real", then ...
What evidence do you have that it is not real?

How does the Tiny Cosmic Ray, having that collision, create a "Gravity Well" or warp spacetime ...
I have no idea what you are talking about.

5. Originally Posted by RussT
Why they are referring to this The answer is the Fitzgerald contraction rather than LT, I will leave it up to the Pro's to suss out.
Isn't the Fitzgerald contraction the same as the Lorentz contraction, and that is why a lot of books write the "Lorentz-Fitzgerald contraction?" If I am not mistaken, they discovered this almost simultaneously.

(Although that would depend on your definition of simultaneity ...)

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Originally Posted by RussT
Here is a slightly different version of how this is 'supposedly' working...

http://galileoandeinstein.physics.vi.../srelwhat.html
Why they are referring to this The answer is the Fitzgerald contraction rather than LT, I will leave it up to the Pro's to suss out.
The Fitzgerald contraction was postulated in 1889 by George Fitzgerald, using calculation by Oliver Heaviside. It was also worked out by Hendrik Lorentz (first in 1892)in his theories of motion. It was proposed to explain the results of the Michelson Morley experiments. It is more popularly known as the Fitzgerald-Lorentz contraction or simply the Lorentz contraction because he gave it a more mathematical formalization. It's simply the length contraction and time dilation of relativity.

Originally Posted by RussT
But, I think the part in Red is the real ? mark, and leads automatically to ATM, and begs the question...IF time dilation is not "Real", then what would be the alternative explanation for the Cosmic Rays hitting the atmosphere and what is happening in those collisions. Nereid? Trinitree88?
There is not alternate explanation. At least that I'm aware of. What is happening is simply the cosmic rays are hitting the atmosphere with sufficient force to create the muons and impart enough energy to propel them to almost c.

Originally Posted by RussT
ETA: I can put this in there....But, I think the part in Red is the real ? mark because...

I can ask the question... How does the Tiny Cosmic Ray, having that collision, create a "Gravity Well" or warp spacetime OR [insert proper wording] for the earth/mountain to fall into or follow the geodesics of curved space?
It doesn't. The time dilation and length contraction are simply the effect of velocity and has nothing to do with gravity, in this case.

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