...and it is negative?
Some sounds might possess a tiny but measurable amount of negative gravitational mass, Scientific American
Phys. Rev. B 97, 134516 (2018) - Mutual interactions of phonons, rotons, and gravity (paywall)
Some sounds might possess a tiny but measurable amount of negative gravitational mass, Scientific American
Phys. Rev. B 97, 134516 (2018) - Mutual interactions of phonons, rotons, and gravity (paywall)
They seem to have built a theoretical model to model sound as particles. No wonder math works.
The sound changes the energy content of a considered volume: no wonder that this has gravitational effects.
Negative mass? This leads to quantum physics and vacuum energy: I can't follow.
The sound changes the energy content of a considered volume: no wonder that this has gravitational effects.
Negative mass? This leads to quantum physics and vacuum energy: I can't follow.
Negative mass? This leads to quantum physics and vacuum energy: I can't follow.
It is not negative mass, it is negative gravity.
“Because their gravitational mass is negative, phonons fall upwards.”
Not sure what the difference between conventional mass and gravitational mass is...guess I need to brush up on my quantum physics..
I think it's not too far off this: A gas with negative gravity still has mass, only it floats away from the gravitational centre in our specific gravity. Orsomethinglikethat.
Edit:
But probably behaves more like a magnetic particle than a gas, only replace "magnetic" with "gravity" sort of.
Edit:
But probably behaves more like a magnetic particle than a gas, only replace "magnetic" with "gravity" sort of.
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I'm reassured that, even though they have negative gravitational mass, I won't have to scrape phonons off the ceiling of my listening room!Quote from the Scientific American article >
"Sound waves having mass are unlikely to have a major impact on day-to-day life"
For interested parties, here's some more on the physics of 'sonic sandblasting'!
Physics - Focus: Sound Waves Carry Mass
This and more information can be found in the following link:The traditional view of sound is that it is a wave motion which transfers energy without transporting mass.
The new theory suggests that sound is a particle motion. The particles of sound are called phonons and they interact with a gravitational field in a way that requires them to transport mass as they move.
For a 1-second-long, 1-watt sound wave in water, the amount of mass would be about 0.1 milligrams. “It’s honest-to-God gravitational mass, the type we experience every day.”
Physics - Focus: Sound Waves Carry Mass
This new theory assumes Newtonian mechanics, so the mass transported by the phonons is unrelated to the equivalence of mass and energy as described by relativistic mechanics.Well sound has energy, energy and mass are related by E=MC^2
Sound is not simply a 'notion', but is classed as one of the main forms of energy along with heat, light, electrical etc. Classically, it is considered that energy is transferred via sound waves without transporting mass and, in that respect, you could say sound is 'massless'.Sound is a human perception/notion - it is massless.
The new theory is a contentious one as the energy transfer is claimed to occur via a particle motion (phonons) which does involve the transport of mass. Still we can rest easy because, at the moment, this is merely a theory and has still to be proved by experiment.
I think we'll hear soon that a speaker converts electrons directly into phonons thus posing another question - are we in danger of running out of electrons?When the speaker runs out of phonons does it stop working?
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