140 decibels. I'm sure some applications exist but it won't be a 3D TV soon.
this post was submitted on 22 Oct 2023
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In an ultrasonic frequency we can’t hear. But your pets and any nearby bats or rodents etc may be upset by it..
Can't hear but still cause damage?
I didn’t know the answer to this so I looked it up - yes. Over 120 Db can cause damage even if it’s ultrasonic and you can’t hear it. Apparently at 155Db the heat created by the sound wave can be dangerous as well.
Just a small note, it's written dB, small "d", big "B".
"B" is the unit symbol for bel and "d" is the symbol for the SI prefix deci, a tenth.
Trust this guy, when it comes to the small d he knows everything about it.
Oops, thanks for the correction!
In that case can we use just B. MB, etc.
Oh yes, sure you can, 140 dB is 0.000014 MB. The confusing thing is just that the non-SI unit byte also uses the symbol "B" and uses the SI prefix "M" quite often.
Sometimes when I calculate optical power levels I actually use B in between. For example:
How much signal is 88 optical channels at 1.6 dBm of power each?
0 dBm = 1 mW by definition
1.6 dB = 0.16 B = log10 ( x ) --> x = 10 ^ 0.16 = 1.45
So 1.6 dBm is 1.45 * 1 mW = 1.45 mW
Then 88 channels is 88 * 1.45 mW = 127.60 mW = 127.60 * 1 mW
log10(127.60) = 2.11 B = 21.1 dB
So 127.20 mW is 21.1 dBm, just below the output specification of our amplifier, good, nothing should melt.
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Yes. Industrial grade ultrasonic sensors are harmful to your health. They can be used, for example, to measure the water level in a tank. If you need to enter a place like that, you should physically disconnect the sensor first. You might not hear much of the noise, but you may feel it in your teeth or some other places.
Weren't there some huge high power sonars that could melt people to goo?
Yep, and hurt whales from the pressure.
Oh, so not all bad then
Loud lightsabers?
Hard light dildos let's fucking goooo
Man, they're going to have remake all the Star Wars porn parodies all over again.
Code Bullet? That you?
Light saber what?
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Light sabers?
Yelling lightsabers at that loudness. All the better imho.
Fun fact, if sound travelled through space, the sun would be as loud as a jackhammer everywhere on earth. Second fun fact, due to the fact that we evolved on earth you wouldve evolved to not be able to hear that frequency.
Luke!
WHAT?
LUKE! I AM YOUR...
WHAAAT? TURN YOUR LIGHTSABER OFF IF YOU GOT SOMETHING TO SAY
HELL NO YOU TURN OFF YOUR LIGHTSABER BOY
Holograms or maybe molecular scale tractor beams?
Holodecks soon?
considering the lab experiment with just one laser required a sound level of about 140 decibels that consume 20 gigawatts, I don't think holodecks are going to be a practical device.
WHAT DID YOU SAY? I CAN'T HEAR YOU OVER MY HOLO-WAIFU
"NOTICE ME SENPAI!!1"
Great points, but you know how things go. Proof of concept is a bloated laboratory implementation, then the tech gets smaller and more efficient over time. Next thing you know the sound is outside of human hearing range and the laser projector is fitted to a drone.
More realisticly how things go, experimental research only works in lab conditions, clickbait article suggests it's coming next year, people make giant assumptions, people lose faith in science because the promised thing doesn't arrive
Lol probably, we are definitely more on track for cyberpunk or idiocracy than star trek post scarcity socialist utopia
So they can only do holodeck simulations of EDM shows.
It may be interesting to see how humidity and temperature influence the laser (or even other gases as mentioned in the article)
So like, ten years at most
It was the laser that's 20 gigawatts, according to the article, which is notable because such a laser is hard to redirect.
As for the viability of holodecks... Obviously the rest of your points are still valid, but one can only hope that someday we'll figure something out, the technology being impossible/unviable right now doesn't mean it'll stay that way. And this seems to show a theoretical possibility of manipulating light mid-air in the necessary way.
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Horseshit. Don't piss on my head and tell me it's raining.
Edit: this is more horseshit like the "room temperature superconductor" that was instantly debunked as a horseshit scheme recently.
Sound pressure waves cannot distort spacetime
Space battles would be so much cooler if every now and then the phaser gets split around the ship instead of hitting the shields.
Would also work even when shields are down.
But that needs air. There's no air in space.
There's an Air and Space Museum
Doesn't need to be air "in space", there just needs to be air somewhere between the laser weapon and whatever it is you don't want the weapon to destroy...
... although it'd probably be easier to use a mirror. Maybe one pointing directly at the person holding a laser weapon. ;-)
Corner reflector. Send it back where it came from, without knowing where they are ahead of time.
Damn... you're right.
Maybe they'll find another way now that they've found one.
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I mean, that's a 20GW laser, what about those handheld lasers? Would you still need 140db?
It would happen regardless of the power of the laser, but it would likely be undetectable at significantly lower power.
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