Does the mass have to be transported at the same speed as the sound or like electron drift in a conductor is the mechanistic speed of movement/translation far far slower?
Sound waves transport a small amount of mass, according to theory
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Re: Sound waves transport a small amount of mass, according to theory
#22I was on a plane today thinking about recent research that uses vibrational/waves to interact with objects. Researchers can suspend and manipulate objects with these waves. I was thinking, why isn’t it possible to use this technology to create levitating objects or vehicles??? Like UFO type flight. Just attach powerful emitters around the craft. This article makes me think this might be possible. F= m*a If waves poss…
Sound waves can move matter [1], and to a lesser degree light can too [2].
[1] Acoustophoretic contactless transport and handling of matter in air https://www.pnas.org/content/110/31/12549
https://en.wikipedia.org/wiki/Sound
https://en.wikipedia.org/wiki/Longitudinal_wave
http://www.people.fas.harvard.edu/~djmorin/waves/longitudina... [pdf]
Re: Sound waves transport a small amount of mass, according to theory
#23In fact, sound waves literally means moving matter! Transporting mass along the wave propagation is a whole different thing. It depends on the matter that is moving/vibrating. While the propagation of kinetic energy through a medium cannot have mass, the mean mass transport through a closed surface should equal zero. However, if they've discovered that it, in fact, isn't - then it's a big deal.
Re: Sound waves transport a small amount of mass, according to theory
#24Earlier quoted context omitted.
Here's one for ya ~> Which came first: Sound or light? https://en.wikipedia.org/wiki/Baryon_acoustic_oscillations
does light make sound?
Gravitational waves resonate at audio frequencies [1], but I am not aware of any findings on that wrt light.
However, you can convert light into sound through the photoacoustic effect [2], and curiously enough, you can recover sound from images through light [3].
[1] Listen to the sound of the kilonova -- the Gravitational Waves Announcement Chirp https://www.ligo.org/science/GW-Inspiral.php
https://theconversation.com/explainer-why-you-can-hear-gravi...
[2] Converting sunlight into audible sound by means of the photoacoustic effect: The Heliophone [pdf] https://core.ac.uk/download/pdf/80794107.pdf
https://en.wikipedia.org/wiki/Photoacoustic_spectroscopy
[3] Veritasium: Can You Recover Sound From Images? [video] https://www.youtube.com/watch?v=eUzB0L0mSCI
See the research Abe Davis is doing on visual vibration analysis: http://abedavis.com
Re: Sound waves transport a small amount of mass, according to theory
#25If you have a nonlinear interaction of a wave with a media, you might have a quadratic term A^2 cos^2(wt). If you remember your trig identities, you'll remember that two sinusoidal functions multiplied together decomposes into the sum of signals at the sum and difference frequencies: cos(w_1 t)cos(w_2 t) = 1/2*(cos((w_1 + w_2)t) + cos((w_1 - w_2)t)). In this case the sum wave is at twice the frequency of the original…
Agree. It's standard quadratic medium rectification, and they've dressed it up so much they can't see it. The rectification will be associated with a uniform translation of the sample the sound wave travels through.
Re: Sound waves transport a small amount of mass, according to theory
#26If this negative mass measurement turns out correct, does it mean that a powerful enough sound wave at a frequency outside hearing range could be the answer to the anti-gravity belt?
Disclaimer: I have no idea what I’m talking about.
Re: Sound waves transport a small amount of mass, according to theory
#27If you have a nonlinear interaction of a wave with a media, you might have a quadratic term A^2 cos^2(wt). If you remember your trig identities, you'll remember that two sinusoidal functions multiplied together decomposes into the sum of signals at the sum and difference frequencies: cos(w_1 t)cos(w_2 t) = 1/2*(cos((w_1 + w_2)t) + cos((w_1 - w_2)t)). In this case the sum wave is at twice the frequency of the original…
Agree. It's standard quadratic medium rectification, and they've dressed it up so much they can't see it. The rectification will be associated with a uniform translation of the sample the sound wave travels through.
The article said that it involved interaction with gravity and wasn't from GR, so that doesn't sound like a complete explanation. Nonlinear phonon interaction has already been demonstrated experimentally, but that doesn't seem to include the additional complexity of the interaction with gravity.
Re: Sound waves transport a small amount of mass, according to theory
#28If you have a nonlinear interaction of a wave with a media, you might have a quadratic term A^2 cos^2(wt). If you remember your trig identities, you'll remember that two sinusoidal functions multiplied together decomposes into the sum of signals at the sum and difference frequencies: cos(w_1 t)cos(w_2 t) = 1/2*(cos((w_1 + w_2)t) + cos((w_1 - w_2)t)). In this case the sum wave is at twice the frequency of the original…
>you might have a quadratic term A^2 cos^2(wt). If you remember your trig identities, you'll remember that two sinusoidal functions multiplied together decomposes into the sum of signals at the sum and difference frequencies: cos(w_1 t)cos(w_2 t) = 1/2(cos((w_1 + w_2)t) + cos((w_1 - w_2)t)).*
The DC component isn't the same as mass transport, because the system still returns to its original state every period of cos(wt). The amplitude of the DC (A^2/2) is also much higher than the one part in a thousand the article was describing.
Re: Sound waves transport a small amount of mass, according to theory
#29In fact, sound waves literally means moving matter ! Transporting mass along the wave propagation is a whole different thing. It depends on the matter that is moving/vibrating. While the propagation of kinetic energy through a medium cannot have mass, the mean mass transport through a closed surface should equal zero. However, if they've discovered that it, in fact, isn't - then it's a big deal.
Sound waves are often compared to water waves in this way. The water just moves up and down, and the horizontal movement is (mostly) an illusion.
But everyone knows intuitively that the water is moving horizontally at least a little bit. Some ocean water gets left on the beach or the boardwalk, or perhaps your toy or ball gets swept out to sea on the waves.
Is this the right analogy, or are they talking about something different?
Re: Sound waves transport a small amount of mass, according to theory
#30If this negative mass measurement turns out correct, does it mean that a powerful enough sound wave at a frequency outside hearing range could be the answer to the anti-gravity belt? Disclaimer: I have no idea what I’m talking about.
The soundwaves float, not the thing producing them.