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Thank you Docscience for helping me adjust my question in a better direction.

My interest has been sparked by getting Into the chapter of waves in physics class and of course the new discovery of gravitational waves. Can a system be engineered to cause a standing wave resonance with gravitational waves? What can we theoretically accomplish by creating a standing wave? What kind of system would we need to be created? How much energy would it take to create a gravitational wave never the less a standing wave resonance from gravitational waves?

Qmechanic
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user26409
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    You're taking "everything" too literally there. Objects or rather systems (can) have resonance frequencies, not forces or general physical phenomena. – ACuriousMind Feb 18 '16 at 00:53
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    Given that your physics professor seems to be making pretty outlandish claims about medicine, there is either a communication problem between the two of you or you would be well advised to change your physics professor. – CuriousOne Feb 18 '16 at 01:02
  • Certain systems are able to trap energy from waves or forces and behave with resonance, but waves, forces by themselves do not resonate, including gravity (waves). Perhaps a better question would be: "Can a system be engineered to cause a standing wave resonance with gravity waves?" From what I've learned recently gravity waves are not easily scattered or reflected, so it would probably be a difficult task. – docscience Feb 18 '16 at 01:36
  • CuriousOne i think he was referring to oscillating pulsed electric field tests on cancer cells. Docscience thank you for the comment. Im going to do more research on the topic and change my answer. In the mean time i will change my question to reflect this new direction. – user26409 Feb 18 '16 at 02:32
  • @user26409 Do you mean something like Weber bars? – Sebastian Riese Feb 18 '16 at 22:03

2 Answers2

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The Wikipedia page has a lot of cool information, and some pretty pictures, though a lot of it's over my head.

What kind of system would we need to be created?

Gravity waves are created by anything with mass moving. A sinusoidal gravity wave would naturally form from a mass moving in a circular pattern, such as a star or planet orbiting something else. On a smaller scale, you can put a bucket on a rope and swing it around your head. Note that the motion can't be spherically or cylindrically symmetric, so a disc or sphere spinning in place won't work. See this answer for more details.

To make a standing wave, you need to create a second wave with the same period somewhere else. (I think one period just has to be an integer multiple of the other period, but I'm a bit rusty.) Note that this will only give you a standing wave in a straight line between the two systems in 3D space. In other directions, you won't have such a neat symmetry.

Here is a cool applet that shows you interference in 2D waves. Note the standing wave between the nodes, and the moving waves everywhere else. 3D waves are more complicated, but similar.

Creating a region (volume) of space filled with standing waves is hypothetical possible, but I have no idea how you'd even start with gravity waves. You can't reflect them, and any giant space-shell made of orbiting planets would collapse onto itself.

Can a system be engineered to cause a standing wave resonance with gravity waves?

Basically you need to do one of two things. First, you can measure the resonance of your third system, then make the standing gravity waves oscillate at the same frequency (or a harmonic frequency). Second, you can measure the frequency of your gravity waves and engineer a system to have the same resonant frequency.

What can we theoretically accomplish by creating a standing wave?

I'm sure there's something out there, but the only thing I know of where you want resonance is a musical instrument. In other cases, you use resonant theories to avoid your system resonating with any high-amplitude local waves, so it doesn't blow up or fall apart.

How much energy would it take to create a gravity wave never the less a standing wave resonance from gravity waves?

Any finite amount of energy can produce a gravity wave or standing wave. However, swinging a bucket over your head produces a gravity wave of practically zero strength. For your gravity wave to produce a non-negligible effect, you need a lot of energy. I don't know that much about the subject, but we're talking really dangerous things like binary neutron stars or black holes. Things you aren't likely to just set up real quick for an impromptu jam session with the band.

This is why it took so long to get any real evidence of them. Almost nothing in the nearby galaxy can produce strong enough gravity waves to detect, and the ones we detected were still tiny.

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MichaelS
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  • Could the gravity waves be reflected off a area of high gravity such as a black hole? Im thinking of it like this. Gravity travels along the medium of space-time. Such as in a ripple tank the waves generated reflect off the walls or interferences in the water that dont move as easily as the water does. So maybe a extremely dense and large black hole can create enough of a "dent" in space-time for the waves to reflect off of? – user26409 Feb 18 '16 at 04:39
  • @user26409 You have to accept the super extreme weakness of the gravitational wave, a black hole is practically a point, there will be diffraction as explained here http://physics.stackexchange.com/questions/237919/is-gravitational-wave-affected-by-gravitational-field/237922#237922 . – anna v Feb 18 '16 at 04:45
  • Please note that for gravitational waves it is not enough to have a changing field ( as for electric and magnetic fields) but also, because of the tensor algebra it obeys, an asymmetry should exist in the system. see my answer and links here http://physics.stackexchange.com/questions/229213/how-are-gravitational-waves-exactly-produced/235756#235756 – anna v Feb 18 '16 at 04:47
  • @annav: In my head, that's what I wrote, but I guess it didn't come out that way. Re-worded it and linked to your answer. – MichaelS Feb 18 '16 at 05:24
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I don't know why people are downvoting this. It's a perfectly good question.

I don't know anything about gravity waves, but I know you detect electromagnetic waves by creating a resonant system that's tuned to the frequency of the source. The biggest problem with detecting gravity waves that way...at least so far as we're talking about the super-powerful waves created by these binary black hole events...is that the SOURCE of the waves is not operating at a constant frequency. The stars orbit faster and faster about each other as they collapse.

You can't design a resonant system to pick up a constantly changing frequency source.

Marty Green
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