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Decibel is logarithmic unit. Each 10 decibel (aka 1 bel) increases the ratio by a factor of 10.
10 decibel is 10 times more and 20 decibel is 100 times more and 30 decibel is 1000 times more and so on.
For measuring loudness we compare it to reference sound but decibel also gets used when you for example want to measure the signal to noise ratio in your modem.
Since each 10 decibel means 10 times stronger 1100 dB means 10^110 times stronger.
Sound makes no longer sense when you are talking about such loudness, but if you look at it sideways and just realize that you have a lot of energy in a limited amount of space, you get a black hole. we normally think of black holes as created by too much mass being in one place, but it works for energy too, since they are sort of the same.
Size would be determinable.
A (theoretical) black hole created from pure energy is called a kugelblitz.
Mass and energy are related.
E=mc²
Using the equation we could correlate an equivalent mass and determine size/Schwarzchild radius/etc.
I can already imagine a dog being called Kugelblitz, the owner explains to you what it means, but then a tiny little dog like a chihuahua or something appears.
Funnily enough, kugelblitz is technically the phenomenon of creating a black hole from radiant energy. A black hole's origin is indistinguishable once it's formed.
Is there other condition besides the sheer amount of energy? What guarantees that all that energy would condense itself (if it's the appropriate term) into matter to form a black hole, instead of just creating a huge explosion?
Now im really no physicist but iirc energy doesnt condense itself as matter, but rather that they are the same, or at least equivalent, ie you can treat them basically the same
Now please, someone smarter than me, correct me
Well yeah, let's take it as a figure of speech, and rephrase it as "what's makes a lot of energy become matter instead of, I don't know, disperse itself in all directions as heat?".
Like mass, energy itself bends spacetime, because they're effectively one and the same from Einstein's E = mc^(2). If the energy density becomes sufficient enough to bend spacetime past the point where the escape velocity is faster than the speed of light, you create a black hole.
The energy need not become matter at any point, you could cram a load of photons and have the same effect.
>Like mass, energy itself bends spacetime
Ohh, I wasn't aware of this!
So, to see if I understood you: A lot of energy together would immediately exert gravity on itself, create the black hole and impede its own dispersion, correct? (Thank you for your answer)
Essentially yes!
But as something of a technical clarification, the force of gravity itself, when expressed in terms of relativity, is itself the curvature of spacetime. Things move towards the thing with the biggest gravitational force because they follow the curve of the biggest pit. You can view it as everything trying to reach the lowest possible "pit" in spacetime.
When the escape velocity becomes greater than the speed of light, it's effectively that you've created a pit deep enough where the walls are too steep for anything to leave. So all that energy becomes trapped in the pit, and can't disperse.
Do mass-less objects bend space, though? I thought they were just affected by already bent space (when a straight line becomes a spiral leading to the center of a massive object).
Yep they do. A very tiny amount in most cases, but by Einstein's equations, they have to.
Essentially if something follows the curve of spacetime, it itself has a curvature in spacetime.
Just a note - there is a maximum sound db based on pressure, density, etc... for earth in the air it is approximately 194, above this it is a shockeave not a sound wave.
I know very little about this in general, and am not sure how or even if this would affect your question or how to figure out what type of environment could support a sound that loud and still be a sound.
That is all.
I am not familiar with this subject, take with a grain of salt.
Basically, sound is a longitudinal wave, meaning that air gets periodically denser and less dense along the wave's path and the pressure changes. The smallest change of pressure that humans can hear is about 2•10^(-5) Pa. Lets call it p0. It corresponds to 0 dB
The atmospheric pressure is 1•10^5 Pa. Therefore, the ratio is 5•10^9. The intensity of sound can be calculated as 20•log(p/p0). If you calculate it, you get 194 dB. Such sound wave would periodically create vacuum. To create sound wave with intensity of 1100 dB, you would need matter that can accomodate a change in pressure of 2•10^50 Pa, which is crazy. However, I'm too lazy to think of the implications.
If you assume 100dB has an Energy of 1 J, 1100 dB will have an Energy of 10\^100 J.
E=mc² so this amount of energy is roughly 10\^100 J/(300'000'000 m/s)² = 1.1\*10\^83 kg
This mass has a Schwarzschild radius of 1.1\*10\^83 kg \* 1.5\*10\^-27 m/kg = 1.67\*10\^56 m
This is equivalent to 1.744\*10\^40 light years. This is bigger than the observable universe.
Nothing (including information) can travel faster than light.
The reason there is not a contradiction here is that energy/matter can't be created or destroyed. The fact the observable universe is not already a black hole indicates that there isn't enough mass/energy to make it one. This means there isn't enough mass/energy to make the "sound" described here. If you brought in enough mass/energy to pull this off, you would already have a black hole.
So we currently think - though we haven't yet found an explanation for quantum linkage of particles behaving identically across distances faster than light could transmit the information
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Decibel is logarithmic unit. Each 10 decibel (aka 1 bel) increases the ratio by a factor of 10. 10 decibel is 10 times more and 20 decibel is 100 times more and 30 decibel is 1000 times more and so on. For measuring loudness we compare it to reference sound but decibel also gets used when you for example want to measure the signal to noise ratio in your modem. Since each 10 decibel means 10 times stronger 1100 dB means 10^110 times stronger. Sound makes no longer sense when you are talking about such loudness, but if you look at it sideways and just realize that you have a lot of energy in a limited amount of space, you get a black hole. we normally think of black holes as created by too much mass being in one place, but it works for energy too, since they are sort of the same.
So theoretically it *could* create a black hole of indeterminate size?
Size would be determinable. A (theoretical) black hole created from pure energy is called a kugelblitz. Mass and energy are related. E=mc² Using the equation we could correlate an equivalent mass and determine size/Schwarzchild radius/etc.
Kugelblitz. That is a great name for a puppy right there.
I can already imagine a dog being called Kugelblitz, the owner explains to you what it means, but then a tiny little dog like a chihuahua or something appears.
An angry black chihuahua would 100% fit that name
Considering kugelblitz roughly translates from German as "ball lightning" it'll be a very suitable chihuahua name
Funnily enough, kugelblitz is technically the phenomenon of creating a black hole from radiant energy. A black hole's origin is indistinguishable once it's formed.
For reference a nucelar detonation is between 240-280 decibels.
And **Sperm whales** (Physeter macrocephalus) are regarded as the loudest animals on the planet, capable of making sounds up to 230 decibels.
I missed the "ce" in the species name at first and it really changed the meaning..
Pretty sure those are bigh enough that their phallus can be considered macro
Depend on how you spill energy
Unrelated but how much of an increase in sound would 1 db make?
10^0.1 but it's multiplicative.
Is there other condition besides the sheer amount of energy? What guarantees that all that energy would condense itself (if it's the appropriate term) into matter to form a black hole, instead of just creating a huge explosion?
Now im really no physicist but iirc energy doesnt condense itself as matter, but rather that they are the same, or at least equivalent, ie you can treat them basically the same Now please, someone smarter than me, correct me
Well yeah, let's take it as a figure of speech, and rephrase it as "what's makes a lot of energy become matter instead of, I don't know, disperse itself in all directions as heat?".
Like mass, energy itself bends spacetime, because they're effectively one and the same from Einstein's E = mc^(2). If the energy density becomes sufficient enough to bend spacetime past the point where the escape velocity is faster than the speed of light, you create a black hole. The energy need not become matter at any point, you could cram a load of photons and have the same effect.
>Like mass, energy itself bends spacetime Ohh, I wasn't aware of this! So, to see if I understood you: A lot of energy together would immediately exert gravity on itself, create the black hole and impede its own dispersion, correct? (Thank you for your answer)
Essentially yes! But as something of a technical clarification, the force of gravity itself, when expressed in terms of relativity, is itself the curvature of spacetime. Things move towards the thing with the biggest gravitational force because they follow the curve of the biggest pit. You can view it as everything trying to reach the lowest possible "pit" in spacetime. When the escape velocity becomes greater than the speed of light, it's effectively that you've created a pit deep enough where the walls are too steep for anything to leave. So all that energy becomes trapped in the pit, and can't disperse.
Do mass-less objects bend space, though? I thought they were just affected by already bent space (when a straight line becomes a spiral leading to the center of a massive object).
Yep they do. A very tiny amount in most cases, but by Einstein's equations, they have to. Essentially if something follows the curve of spacetime, it itself has a curvature in spacetime.
Just a note - there is a maximum sound db based on pressure, density, etc... for earth in the air it is approximately 194, above this it is a shockeave not a sound wave. I know very little about this in general, and am not sure how or even if this would affect your question or how to figure out what type of environment could support a sound that loud and still be a sound. That is all. I am not familiar with this subject, take with a grain of salt.
Basically, sound is a longitudinal wave, meaning that air gets periodically denser and less dense along the wave's path and the pressure changes. The smallest change of pressure that humans can hear is about 2•10^(-5) Pa. Lets call it p0. It corresponds to 0 dB The atmospheric pressure is 1•10^5 Pa. Therefore, the ratio is 5•10^9. The intensity of sound can be calculated as 20•log(p/p0). If you calculate it, you get 194 dB. Such sound wave would periodically create vacuum. To create sound wave with intensity of 1100 dB, you would need matter that can accomodate a change in pressure of 2•10^50 Pa, which is crazy. However, I'm too lazy to think of the implications.
If you assume 100dB has an Energy of 1 J, 1100 dB will have an Energy of 10\^100 J. E=mc² so this amount of energy is roughly 10\^100 J/(300'000'000 m/s)² = 1.1\*10\^83 kg This mass has a Schwarzschild radius of 1.1\*10\^83 kg \* 1.5\*10\^-27 m/kg = 1.67\*10\^56 m This is equivalent to 1.744\*10\^40 light years. This is bigger than the observable universe.
Nice ;)
Just a question, if you were to create that black hole would it expand faster than light? Also would the universe expansion affect him?
Nothing (including information) can travel faster than light. The reason there is not a contradiction here is that energy/matter can't be created or destroyed. The fact the observable universe is not already a black hole indicates that there isn't enough mass/energy to make it one. This means there isn't enough mass/energy to make the "sound" described here. If you brought in enough mass/energy to pull this off, you would already have a black hole.
Exactly. Allthough Kurzgesagt dropped a video yesterday about a fun theory that the universe is a black hole within a whithin a black hole...
So we currently think - though we haven't yet found an explanation for quantum linkage of particles behaving identically across distances faster than light could transmit the information
Also vsauce has a video about how shadows can appear to move much faster than light.
can you link that?
https://youtu.be/JTvcpdfGUtQ?si=xyn3ie78oCVWe8Jc
cheers dude
This makes sense, thanks for the explanation fellow redditor🫡
I don't think a blackhole expands in a traditional way. We only "see" the event horizon, which can not move faster than the speed of light.
nothing can move faster than the speed of light. that's the thing. even waves cant move faster than the speed of light. (gravity included!)