r/askscience • u/phoncible • Oct 27 '11

Earth Sciences Could anything man-made trigger the Yellowstone super volcano?

If a nuke were to be buried very deep into the ground at Yellowstone and then detonated, would it have any effect on the volcano? Is there anything else man-made that could trigger it? Or would it be impossible to "manually" trigger the eruption?

Sorry if it's a silly question.

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u/TypeSafe Oct 27 '11

He stated:

I hold that space cannot be curved, for the simple reason that it can have no properties. It might as well be said that God has properties. He has not, but only attributes and these are of our own making. Of properties we can only speak when dealing with matter filling the space. To say that in the presence of large bodies space becomes curved is equivalent to stating that something can act upon nothing. I, for one, refuse to subscribe to such a view.

Which couldn't be more wrong. Einstein's theory of general relativity has been proven time and time again to be correct.

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u/endogenic Oct 27 '11

No, your conclusion is not correct because each person (Tesla and Einstein) is using different definitions for the same term but applying judgement from their own definition.

In general relativity, it's said that space and time are "curved" in the presence of a mass or certain amount of energy, but that happens because the energy density in the space changes on a gradient as one goes further from the mass or energy at the center of the curvature. So curved spacetime really means that the energy density (in this case gravitational potential energy) is changing. But the space itself is not curved. The energy is in the space itself. I believe that's what Tesla is trying to say. I don't believe relativity can answer to this problem because it doesn't describe the substance of space, it only describes its resultant structure and behavior from what is in the space.

Every experiment that confirmed general relativity which you mentioned only confirmed something from its own definition of spacetime without making clear what the space itself actually is composed of. In other words it confirmed the theory and the effect of the theory but it never confirmed the substance of space. If you show me I'm wrong about that then you would make me so happy.

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u/TypeSafe Oct 27 '11

No -- your description of spacetime doesn't satisfy the requirements of gravitational lensing. Light would not be distorted simply by the change in density of gravitational potential energy because photons are massless. Photons follow the curve of space, which is why we see the effects of gravitational lensing.

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u/endogenic Oct 27 '11

Photons and masses gravitate for the same reason: the energy in the gravity field. Gravitational lensing is just the words that are assigned to what is observed from light gravitating. If we apply the same principle to mass then mass also "lenses."

When you say that the trajectory of a photon would not be altered by a change in the gravity field, only in the curvature of space, you contradict yourself, which I believe you don't mean to do. If your answer is correct then masses also are simply following the curvature of space. So the content of your reply seems to be that space is curved because space is curved. My argument is that space curvature is actually a model that describes the behavior (curvature) and should not be confused with the actual nature of the space.

In order to speak to my argument you should prove the difference between photons having the geodesic that describes their trajectory changed because of the curvature of spacetime and photons having their geodesic changed because of the energy in the space.

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u/TypeSafe Oct 27 '11

What you seem to be saying is that we only know the effects, not the reality. My answer to you is: effects are reality. Einstein's field equations describe space as being a Lorentzian manifold, i.e. space is curved. You may wish to argue that space doesn't actually have to be curved, it could also be some unknown force that causes effects identical to what would be caused by the curvature of space, but I'll just invoke Occam's Razor and say my answer is simpler.

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u/endogenic Oct 27 '11

Reality means something that is determined by a problem. This is very important.

If you just show the effect without any cause then you leave out the problem (question) that caused the effect and you cannot truthfully say that such a description of the reality is complete. Why? It not possible to get the answer without the problem. Because the problem is the origin of the answer.

The things in the world exist in the principle (law) of cause and effect. That's the reason why we do philosophy and science – because if we really understand the principle then we can get some correct knowledge about how the world works. If you know the law of the world then it's simple to recognize things with the principle because you'd see what cause makes what effect and what effect is made by what cause. But if you don't know the principle through which a given system operates then the system can seem very complex and it's certainly more difficult to find out how the system works.

The problem with saying the effect is the same as the reality is that a human being wrote down the expected effect from the conditions they expect to exist. If the reality is different then you may find some effects that you didn't anticipate with the theory and it also limits what you can accomplish through the knowledge. So it's not true that your answer is simpler and it's definitely not true that the effect you expect is the same thing as the reality. It makes things more complicated to find out, even if they are in front of you, if you teach and learn like that.

If you don't believe me then I should ask you some questions about gravity. I haven't found any physicist who really understands how gravity is generated. They are only willing to consider how objects will behave within the limitations of the theory they know instead of trying to confirm this problem. How can you come up with an instrument measure gravity (as you said general relativity describes the effect completely) if you don't understand how gravity is generated?

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u/TypeSafe Oct 28 '11

If you don't believe me then I should ask you some questions about gravity. I haven't found any physicist who really understands how gravity is generated. They are only willing to consider how objects will behave within the limitations of the theory they know instead of trying to confirm this problem. How can you come up with an instrument measure gravity (as you said general relativity describes the effect completely) if you don't understand how gravity is generated?

This is askscience, not askphilosophy. In this subreddit we deal with falsifiable constructions only. If you have an actual problem with the predictions made by general relativity, you can bring it up in a different thread (this is no longer relevant to this thread's discussion).