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originally posted by: BASSPLYR
I have another question.

can plasma be used to absorb kinetic energy to some degree? specifically. can it convert to any degree incoming sound waves like say a sonic shock wave to some other energy, like photons?

I wouldn't say photons as opposed to collective fluid-EM field waves. MHD is the coupling of electromagnetism with fluid mechanics.

i.e. could one theoretically use the exhaust stream to absorb sonic pressure wave energy enough to cause a reduction in decible via finessing the exhaust stream into some plasma sheath extending a distance behind say an aircraft engine.

in effect creating a virtual extension of the fuselage length to absorb more sonic shock pressure, which would have a side effect of converting some of that sound into light (in the form of further exciting exhaust particles, that tend to remain glowing longer than usual)

You really don't want more drag.

Better I think to soften the 'shock wave' --- which is a singularity in the continuum fluid mechanics. As in the speed of sound when you combine the fluid with EM modes which can propagate faster in this plasma is substantially higher (as in you can transfer momentum from particles in the fluid to others via the EM waves and not just by mechanical pressure), so that what was a supersonic 'shock' in neutral air is no longer supersonic and so you don't have a shock any more, just a wake & waves.

It's EXTREMELY complicated, and there are an enormous variety of very complex modes & stability considerations.

a reply to: mbkennel

i think your going to probably say nope i get yeah and no its still really complicated. but what i wanted to say is this.

say you have a aircraft flying at supersonic speeds could you in theory. ionize the exhaust and make it so that it basically created like a plasma fillimet behind the aircraft (or just introduce plasma to ionized exhaust stream) that absorbs the supersonic pressure waves to some degree lowering the decibles of the boom.

if the plasma is being ejected out the back like a flame how would it add drag to the aircraft?

if a sonic pressure wave is impacting with Said plasma filiment would some of the ionized particulates in the exhaust stream take on a little of that converted energy and cause the particulates that are already glowing to glow or be excited for a little longer?

could one theoretically use this as a way to help dampen a sonic boom?

also would the hypothetical absorption of the sound pressure help to confine the exhaust stream and keep it tidy, narrow and concise?

a reply to: BASSPLYR

ionize the exhaust and make it so that it basically created like a plasma fillimet behind the aircraft (or just introduce plasma to ionized exhaust stream) that absorbs the supersonic pressure waves to some degree lowering the decibles of the boom.

What happens in the exhaust of the aircraft has no effect on the production of pressure waves. Pressure waves originate when various components of the aircraft exceed the speed of sound.

if the plasma is being ejected out the back like a flame

It isn't.

could one theoretically use this as a way to help dampen a sonic boom?

It wouldn't seem so.

also would the hypothetical absorption of the sound pressure help to confine the exhaust stream and keep it tidy, narrow and concise?

Which has nothing to do with a sonic boom.

a reply to: Phage

I get why the pressure waves are formed. I want to know if you can absorb some of them with plasma to lessen the boom. like how they are using plasma discharges or something similar to absorb, convert or mitigate (whatever it does) to a small degree the shockwaves from exploded ordinance.

as for the tidy and concise question that ones not about the sonic boom but a reference to a certain characteristic of a certain aircraft.

a reply to: BASSPLYR

I want to know if you can absorb some of them with plasma to lessen the boom.

I don't see how it could since the sonic boom travels with the aircraft, not the exhaust which gets left behind.

a reply to: Phage

you may be right.

I know that really long skinny fuselages would lead to much reduced sonic booms and theoretically solve a boom problem. but having a thousand foot long skinny fuselage is impractical. I was figuring he why not use the exhaust somehow to generate a plasma filiment and basically create a virtual extension of the fuselage. in effect making a really slender thousand foot long fuselage.

I mean you already have the exhaust creating a filiment of super heated air for several thousands of feet behind the aircraft. seems like a waste to not convert it into some sorta plasma (I dunno further super heat the air by using pulsed lasers aimed into the exhaust or something) and create a virtual extension of sorts with the rear of tge aircraft.

know they can do it with plasma on the front of the aircraft. I know they can do it to create virtual cowlings infront of the air intakes. all using pulsed lasers. just seeing if there is a way to double down and do something similar on the rear. instead of just creating a simple plasma bloom like on the front end. maybe convert the exhaust into like a plasma contrail. not as effective as maybe the plasma blooms in front but still contributing to the good? get twice the sound reduction effects?

originally posted by: BASSPLYR
can plasma be used to absorb kinetic energy to some degree? specifically. can it convert to any degree incoming sound waves like say a sonic shock wave to some other energy, like photons?

The kinetic energy of the pistol shrimp's claw snapping results in the creation of plasma. These folks captured it on high speed camera and you can see the snap, the expanding bubble, then the collapsing bubble and plasma inside the bubble, it's fascinating:

Slow motion pistol shrimp attack hits 4000⁰C! - Slo Mo #14 - Earth Unplugged

originally posted by: ATSAlex
For the physics experts here, I have a question:

Can a ship using warp drive create a wake, ripples or waves in the space time fabric? I mean something similar to a speed boat traveling fast in a lake creates a wake that is visible and measurable in the water.

I don't consider myself an expert in warp drive physics, and I'm not sure if there really is one but if there is, it would be Sonny White at NASA. He gave an hour long talk about Eagleworks labs in which he talks about warp drive and other technologies his lab is researching like the Q-thruster. It's well worth the hour to watch it for anybody interested in this topic.



At 18 minutes he says his analysis has moved the warp drive idea from completely impossible to maybe plausible, but this doesn't mean it's feasible (which he said sometimes gets overlooked), so one possibility is that the warp drive isn't feasible, rendering any questions about the side effects such as wakes irrelevant.

At 55 minutes he talks about measuring the wake of the Q-thruster which is a less speculative but still controversial technology because some people have claimed it violates conservation of momentum. He doesn't talk about measuring the wake of a warp drive, as he's probably more concerned about whether it's possible to even make a warp drive.

originally posted by: BASSPLYR
a reply to: Phage


know they can do it with plasma on the front of the aircraft. I know they can do it to create virtual cowlings infront of the air intakes. all using pulsed lasers. just seeing if there is a way to double down and do something similar on the rear. instead of just creating a simple plasma bloom like on the front end. maybe convert the exhaust into like a plasma contrail. not as effective as maybe the plasma blooms in front but still contributing to the good? get twice the sound reduction effects?

I had a good dig around along the lines of super refined "Sasers" (i.e Sound Lasers) and phonon conversions but couldn't find anything you would hang your hat on.

If someone invented some sort of swiss army knife EM emitter (like in Star Trek) I wonder if it would be possible to either alter the manifesting components of the boom or alternatively......re-direct or disperse the effects?

Cancelling out a boom completely seems overkill when you could just ensure its effects don't reach the ground by disrupting the conventional mechanics at play.

a reply to: Jukiodone

juki. I agree cancelling a boom altogether is not realistic. dampening it would be great though. people often argue. why mitigate the boom of something flying so high up that you wouldn't realky hear it anyways. but what if wanted that same thing to fly lower. low enough for a boom to be a problem..

arbi,

excellent video. knew about mantis shrimp but the pistol shrimp might be even cooler. loved the slow motion where you could see the plasma generate. very cool.

I love this thread. I always learn really neat things. this thread has a lot of value. thanks to all the folks contributing.

originally posted by: BASSPLYR
a reply to: Jukiodone

juki. I agree cancelling a boom altogether is not realistic. dampening it would be great though. people often argue. why mitigate the boom of something flying so high up that you wouldn't realky hear it anyways. but what if wanted that same thing to fly lower. low enough for a boom to be a problem..

I dont fully understand the physics but altering the sonic boom propagation point theory seems to have merit as well.

If something could/is required to operate at low levels with zero "engine noise" would it ever need to travel faster then 700 MPH/whatever it's sonic boom threshold is ???

Stood under some Tornadoes doing low level practice and they would have been very difficult to spot at sub mach speeds if it werent for the accompanying earthquake and skyquake as they roared overhead.

originally posted by: BASSPLYR
excellent video. knew about mantis shrimp but the pistol shrimp might be even cooler. loved the slow motion where you could see the plasma generate. very cool.

It's not just cool to see it in slow motion (which it is), but you could never even see what's happening with a regular camera shooting at 25 frames per second, where a single frame is 0.04 seconds long. The action was all over in 8 frames at 10,000 frames a second, or 0.0008 seconds.

It's not related to airplanes but it's still a fascinating phenomenon, sonoluminescence. The same photographers who videoed the pistol shrimp also videoed the mantis shrimp but they weren't able to capture the sonoluminescence, which occurs sometimes when it strikes its prey as opposed to snapping its claw like the pistol shrimp:

originally posted by: BASSPLYR
a reply to: mbkennel

i think your going to probably say nope i get yeah and no its still really complicated. but what i wanted to say is this.

say you have a aircraft flying at supersonic speeds could you in theory. ionize the exhaust and make it so that it basically created like a plasma fillimet behind the aircraft (or just introduce plasma to ionized exhaust stream) that absorbs the supersonic pressure waves to some degree lowering the decibles of the boom.

The shock waves are created at the nose of the aircraft. I think it's the front you have to worry about and that's hard since the air is coming at you pretty fast.

if the plasma is being ejected out the back like a flame how would it add drag to the aircraft?

It wouldn't but it wouldn't help either. I think I was talking about something else in reply to you.

could one theoretically use this as a way to help dampen a sonic boom?

Sonic booms don't come out the engines. At least naively, if you need to modify the sonic boom, you have to modify it where it forms. My picture was microwaves or something trying to form/squirt plasma in front of the nose, so that in the area where the boom would form the speed of sound is much higher, so that you don't really have a shockwave any more (regular subsonic compressible flow, as if you were in helium or something) and you have a smoother transition to regular air so you don't get as strong an impulse shock wave.

It also seems that any plasma out in front technology could really degrade forward radar, both incoming and outgoing, so it wouldn't be so hot for electronic surveillance or search & detection.

Lol. these characters need a shave b4 coming in a video. yuck
a reply to: Arbitrageur

Hey Arbitrageur, don't know what you physics training is, maybe science PhD or something. Also maybe there are other people on this forum that have physics/science graduate or higher diplomas...
Maybe you and anyone else that can read/make/do real science in a real lab just have a look and skim read at least some papers posted by this guy on vixra archive and the info on this PhD guy called Stoyan Sargoytchev. I've linked all the info in this topic.
www.abovetopsecret.com...
Basically he's got this theory of his and also his own model of electron/protons/neutron trajectories/orbits and stuff...
I understand that out of 3 or 4 book published, apparently he works at York uni in toronto ?!?, out of his 3-4 book, 1, the ''Bsm- supergravity unified theory'' is 400 pages of jampacked science thats unreadable my mere mortals without a science background.
Can you have a look ? He's got this ''heterodyne resonance mechanism'' which interacts with som eplasma which interacts with space/vacuum itself..can't quite figure it out, but the guy seems legit.

a reply to: BASSPLYR

I'm not trying to challenge your assertion about the virtual cowlings, but do you have a link or something to this tech? I have never heard of this. I'd like to take a look at the information.

a reply to: Arbitrageur

THAT is an awesome video. Thanks, Arbitrageur. I had heard of the pistol shrimp, but didn't really know any of the specifics of the claw speed. And I thought previously that the sound it produces was just from the concussive force of the claw closing. But no, it had to go all 'plasma physics crustacean' and be an amazingly cool animal. Fantastic.

a reply to: Choice777

Red flags:

Research posted exclusively on the "World Institute for Science Exploration" (a pseudoscience vanity press) and YouTube, thus avoiding serious engagement and criticism from the scientific community.

Real scientists write scientific papers to be peer reviewed and published in credible journals, welcome criticism. Pseudoscientists appeal directly to the layperson, attempting to capitalize on their scientific illiteracy and avoid scientific scrutiny.

a reply to: GetHyped

That reminds me of the 'Electric Universe' proponents. I'm not knocking them, mind you. But that seems to be the main way their research is presented.

.

a reply to: Choice777

You would rather accept the findings of:

a) science

b) pseudoscience

Pick 1. You don't get to mix and match as it suits you.

If you cannot see blatant red flags for what they are then that is your problem. Feels do not trump reals.