No, I don't think that at all! I just query whether the fluid dynamics of the intergalactic medium is moderated by photons.
There are published works on the fluid dynamics of the interstellar and intergalactic medium e.g. 35. Fluid Dynamics
https://hal.archives-ouvertes.fr/hal-02900844/document
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Very well.
I was just wondering about it, since even quite basic things can have an impact on ocean currents or winds and weather systems for that mattet.
This is the backdrop of my question, if space can be compared to a vast ocean using fluid dynamics, with eddies and currents, weather phenomena and the like.
Since space has inherently less resistance than air, would it not require less energy to influence what is there?
I was just wondering about it, since even quite basic things can have an impact on ocean currents or winds and weather systems for that mattet.
This is the backdrop of my question, if space can be compared to a vast ocean using fluid dynamics, with eddies and currents, weather phenomena and the like.
Since space has inherently less resistance than air, would it not require less energy to influence what is there?
I am not an expert on the fluid dynamics of the IGM or ISM, but the influence will come from gravitational and electromagnetic fields.
Just imagine how complicated the fluid dynamics is in the matter accretion disk which swirls around some black holes!
Accretion disk - Wikipedia
I think near vaccum does not follow usual fluid dynamics. Pressure becomes odd.
To create vaccum, one must pump air out of some enclosure. The first down PSI, Bar, Pa, hPa whatever pressure units, are easy to get.
Then comes very low pressure where air molecules do not act in a Brownian way, they speed their way straight ahead, little bumping each other. Then they move back and forth bumping on the enclosure walls. Then one needs very large pipes to get a chance to have them go out to reach the pump.
BTW, the pump is a secondary one type, trapping air by moving oil.
Going at better vaccum, one need traps for residual stuff incrusted in materials.
Finally, it is not possible to make vaccum as good as in outerspace.
So there is definitely two different behavior: Usual pressures where fluids are described by Brownian movements, and below where it is more like playing Pong.
To create vaccum, one must pump air out of some enclosure. The first down PSI, Bar, Pa, hPa whatever pressure units, are easy to get.
Then comes very low pressure where air molecules do not act in a Brownian way, they speed their way straight ahead, little bumping each other. Then they move back and forth bumping on the enclosure walls. Then one needs very large pipes to get a chance to have them go out to reach the pump.
BTW, the pump is a secondary one type, trapping air by moving oil.
Going at better vaccum, one need traps for residual stuff incrusted in materials.
Finally, it is not possible to make vaccum as good as in outerspace.
So there is definitely two different behavior: Usual pressures where fluids are described by Brownian movements, and below where it is more like playing Pong.
What we need is more reference material on 'astrophysical fluid dynamics'! 😉
Astrophysical fluid dynamics - Wikipedia
Magnetohydrodynamics - Wikipedia
Astrophysical fluid dynamics - Wikipedia
Magnetohydrodynamics! 😱
Magnetohydrodynamics - Wikipedia
You can’t use fluid dynamics in a vacuum because there is no kinetic energy transfer between objects - excluding here of course throwing a ball for example against a metal plate. There the ball has kinetic energy. In a vacuum, there’s to enough atoms of molecules to bump into each other as there is on earth for example.
As to the question ‘how does an EM wave propagate thru a vacuum?’ We know how to predict it (Maxwell) but precisely what it is we don’t know. Daniel Fleisch warns students that it is a ‘deeply philosophical’ question.
Personally, I venture that it propagated via the ‘time field’.
Now Galu has every right laugh at me but that’s my guess. 🙂
As to the question ‘how does an EM wave propagate thru a vacuum?’ We know how to predict it (Maxwell) but precisely what it is we don’t know. Daniel Fleisch warns students that it is a ‘deeply philosophical’ question.
Personally, I venture that it propagated via the ‘time field’.
Now Galu has every right laugh at me but that’s my guess. 🙂
I have no problem understanding that the "matters of the void" (great name for a tune!) are few and far between.
But the volume of space itself is so incredibly vast, that even if the particles are so few per unit of volume the sheer amount of volume might account for something.
But the volume of space itself is so incredibly vast, that even if the particles are so few per unit of volume the sheer amount of volume might account for something.
Absolutely spot on. Although the particle density may be low, the humongous volume of space means there is an unimaginably large number of matter particles floating around out there!
Speaking of fluids, not sure if you guys have seen this classic on superfluid helium.
Superfluid helium - YouTube
Superfluid helium - YouTube
Kaffiman, you have described one of my Physics disasters! 😀
The brief from Doctor Mansfield to the student and Lab technician was simple enough.
Immerse a bit of Indium antimonode in Liquid Helium, with a magnetic Field, and we might see the Quantum Hall Effect.
All went horribly wrong. Liquid Helium is not cheap. About £4,000 a Kilo bottle.
We poured about 4 bottles on the semi-conductor. I could see nothing through the microscope. 😕
We gave up and hit the College Bar. Ah well, what's a Nobel Prize? 😱
The brief from Doctor Mansfield to the student and Lab technician was simple enough.
Immerse a bit of Indium antimonode in Liquid Helium, with a magnetic Field, and we might see the Quantum Hall Effect.
All went horribly wrong. Liquid Helium is not cheap. About £4,000 a Kilo bottle.
We poured about 4 bottles on the semi-conductor. I could see nothing through the microscope. 😕
We gave up and hit the College Bar. Ah well, what's a Nobel Prize? 😱
The universe actually used to be the size of our galaxy.
Perhaps we should look back in time!
The observable universe had the same size as our galaxy when it was approximately 3 years old, when it was much hotter and denser than it is now.
Right, but if it didn't get any bigger, would particle/photon interaction be any different even if current particle density was condensed down to that size?
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