OceanBreeze Posted June 15, 2017 Report Posted June 15, 2017 Some people call the CMBR an "echo" of the big bang, which is a slightly unfortunate metaphor as no sound is involved. Afraid I must disagree with that last bit. There ARE “sound” waves superimposed into the CMB, but they are quite different from what we usually mean when we speak about sound. At the time when the CMB was formed, the universe was filled with a hot dense plasma that was oscillating due to temperature fluctuations, resulting in the sort of mechanical vibrations that we commonly call sound waves. However, because the plasma was so dense, these “sound” waves, which are more properly called acoustic waves, travelled at 60% of the speed of light! At least one physicist, John Cramer of the University of Washington, fed the acoustic data that is superimposed on the CMB into a computer program called Mathematica, which converted them to sound. A 100-second recording represents the sound from about 380,000 years after the Big Bang until until about 760,000 years after the Big Bang.You can listen to it here. Quote
Super Polymath Posted June 15, 2017 Report Posted June 15, 2017 Afraid I must disagree with that last bit. There ARE “sound” waves superimposed into the CMB, but they are quite different from what we usually mean when we speak about sound. At the time when the CMB was formed, the universe was filled with a hot dense plasma that was oscillating due to temperature fluctuations, resulting in the sort of mechanical vibrations that we commonly call sound waves. However, because the plasma was so dense, these “sound” waves, which are more properly called acoustic waves, travelled at 60% of the speed of light! At least one physicist, John Cramer of the University of Washington, fed the acoustic data that is superimposed on the CMB into a computer program called Mathematica, which converted them to sound. A 100-second recording represents the sound from about 380,000 years after the Big Bang until until about 760,000 years after the Big Bang.You can listen to it here.If we're listening to it, it's been translated into molecular sounds by software. The mechanical vibrations in the electromagnetic clouds of the early universe are not sounds by any criteria. Quote
OceanBreeze Posted June 15, 2017 Report Posted June 15, 2017 If we're listening to it, it's been translated into molecular sounds by software. Yes, of course software was required to make the sounds audible to the human ear The mechanical vibrations in the electromagnetic clouds of the early universe are not sounds by any criteria You are wrong. These were true sound waves travelling within an extremely dense medium, and not in "electromagnetic clouds" This is from the source I linked: “The original sound waves were not temperature variations, though, but were real sound waves propagating around the universe,”The plasma was far more dense than any medium in existence today, thus the sound waves travelled very fast, 60% of light speed. Quote
Super Polymath Posted June 15, 2017 Report Posted June 15, 2017 Yes, of course software was required to make the sounds audible to the human ear You are wrong. These were true sound waves travelling within an extremely dense medium, and not in "electromagnetic clouds" This is from the source I linked: “The original sound waves were not temperature variations, though, but were real sound waves propagating around the universe,”The plasma was far more dense than any medium in existence today, thus the sound waves travelled very fast, 60% of light speed.The hot dense plasma that you're referring to are the electromagnetic clouds of the quark epoch. Sound is caused by changes in air density. No air = no sound. Quote
OceanBreeze Posted June 15, 2017 Report Posted June 15, 2017 The hot dense plasma that you're referring to are the electromagnetic clouds of the quark epoch. Sound is caused by changes in air density. No air = no sound. A hot dense plasma, much more dense than any material around today, is not a "cloud". Sound travels better through dense materials than it does through air. It will even travel through your dense head. Turtle 1 Quote
billvon Posted June 16, 2017 Report Posted June 16, 2017 The hot dense plasma that you're referring to are the electromagnetic clouds of the quark epoch. Sound is caused by changes in air density. No air = no sound. Nonsense. You can transmit sound through any gas, liquid or plasma. (Google how dolphins use sound, for example.) Turtle 1 Quote
exchemist Posted June 16, 2017 Report Posted June 16, 2017 Yes, of course software was required to make the sounds audible to the human ear You are wrong. These were true sound waves travelling within an extremely dense medium, and not in "electromagnetic clouds" This is from the source I linked: “The original sound waves were not temperature variations, though, but were real sound waves propagating around the universe,”The plasma was far more dense than any medium in existence today, thus the sound waves travelled very fast, 60% of light speed. Afraid I must disagree with that last bit. There ARE “sound” waves superimposed into the CMB, but they are quite different from what we usually mean when we speak about sound. At the time when the CMB was formed, the universe was filled with a hot dense plasma that was oscillating due to temperature fluctuations, resulting in the sort of mechanical vibrations that we commonly call sound waves. However, because the plasma was so dense, these “sound” waves, which are more properly called acoustic waves, travelled at 60% of the speed of light! At least one physicist, John Cramer of the University of Washington, fed the acoustic data that is superimposed on the CMB into a computer program called Mathematica, which converted them to sound. A 100-second recording represents the sound from about 380,000 years after the Big Bang until until about 760,000 years after the Big Bang.You can listen to it here.Thanks, that is something I did not know. But, just for the avoidance of any confusion among other readers, this is an extra pattern or signal, due to sound waves in the primordial universe, which can be detected within the CMBR spectrum and decoded. Nobody is suggesting that the CMBR is sound or makes a sound, any more than a radio signal makes a sound. DrKrettin and OceanBreeze 2 Quote
Super Polymath Posted June 16, 2017 Report Posted June 16, 2017 Nonsense. You can transmit sound through any gas, liquid or plasma. (Google how dolphins use sound, for example.)Water, & the clouds in the sky, are similar to oxygen on a molecular level. The electromagnetic clouds of the quark epoch, however, were not even composed of molecules of any kind. Quote
Super Polymath Posted June 16, 2017 Report Posted June 16, 2017 Nobody is suggesting that the CMBR is sound or makes a sound, any more than a radio signal makes a sound. Except our equipment that receives & converts radio signals into audio frequencies actually do make noise. To answer the OP, NO; photons are not noisy because photons are sub-sonic. Quote
DrKrettin Posted June 16, 2017 Report Posted June 16, 2017 To answer the OP, NO; photons are not noisy because photons are sub-sonic. You learn something every day. I thought that light was faster than sound. Quote
Super Polymath Posted June 16, 2017 Report Posted June 16, 2017 (edited) You learn something every day. I thought that light was faster than sound.Than you failed to take my meaning. A photon is also smaller than the changes in air density that produces sound waves. Edited June 16, 2017 by Super Polymath Quote
Super Polymath Posted June 16, 2017 Report Posted June 16, 2017 That's what I said. This is why Hazelm thought photons can make noise. Don't be overly pedantic to the layman. A photon is smaller than a single molecule of any medium, Hazelm. Sound is produced by molecules, changes in air density, particles don't even register. Same reason why the speed of light is far faster than the speed of sound. Quote
OceanBreeze Posted June 16, 2017 Report Posted June 16, 2017 The electromagnetic clouds of the quark epoch, however, were not even composed of molecules of any kind. Here is proof that even a blind squirrel can find a chestnut once in a while. All you need for sound waves is a medium composed of some mass through which the compression wave can propagate. Normally, this medium is composed of molecules, as you said, and that is an interesting point. At the time when the CMB was formed, about 380,00 years after the BB, the universe was filled with a primordial plasma made of photons, plus electrons and protons that had not yet recombined or were in the process of recombining, into atoms or molecules of matter. However, electrons and protons are fermions and charged particles. As such, unlike photons, they obey the exclusion principle; they cannot occupy the same space at the same time or pass through each other. Instead, they push against each other and that satisfies the requirement for a pressure wave, such as a sound wave, to propagate. So, sound waves do not need molecules in order to propagate; atoms or even just fermions that are outside atoms, will do just fine. There is no doubt that sound waves did propagate throughout the primordial plasma, as they can still be detected today as a superposition in the CMB; a remarkable fact that yields valuable information about the early universe. exchemist 1 Quote
OceanBreeze Posted June 16, 2017 Report Posted June 16, 2017 To answer the OP, NO; photons are not noisy because photons are sub-sonic. And here is proof that the poor squirrel is really blind. Quote
exchemist Posted June 16, 2017 Report Posted June 16, 2017 Here is proof that even a blind squirrel can find a chestnut once in a while. All you need for sound waves is a medium composed of some mass through which the compression wave can propagate. Normally, this medium is composed of molecules, as you said, and that is an interesting point. At the time when the CMB was formed, about 380,00 years after the BB, the universe was filled with a primordial plasma made of photons, plus electrons and protons that had not yet recombined or were in the process of recombining, into atoms or molecules of matter. However, electrons and protons are fermions and charged particles. As such, unlike photons, they obey the exclusion principle; they cannot occupy the same space at the same time or pass through each other. Instead, they push against each other and that satisfies the requirement for a pressure wave, such as a sound wave, to propagate. So, sound waves do not need molecules in order to propagate; atoms or even just fermions that are outside atoms, will do just fine. There is no doubt that sound waves did propagate throughout the primordial plasma, as they can still be detected today as a superposition in the CMB; a remarkable fact that yields valuable information about the early universe. I like your explanation in terms of the Exclusion Principle. Quote
Super Polymath Posted June 16, 2017 Report Posted June 16, 2017 Here is proof that even a blind squirrel can find a chestnut once in a while. All you need for sound waves is a medium composed of some mass through which the compression wave can propagate. Normally, this medium is composed of molecules, as you said, and that is an interesting point. At the time when the CMB was formed, about 380,00 years after the BB, the universe was filled with a primordial plasma made of photons, plus electrons and protons that had not yet recombined or were in the process of recombining, into atoms or molecules of matter. However, electrons and protons are fermions and charged particles. As such, unlike photons, they obey the exclusion principle; they cannot occupy the same space at the same time or pass through each other. Instead, they push against each other and that satisfies the requirement for a pressure wave, such as a sound wave, to propagate. So, sound waves do not need molecules in order to propagate; atoms or even just fermions that are outside atoms, will do just fine. There is no doubt that sound waves did propagate throughout the primordial plasma, as they can still be detected today as a superposition in the CMB; a remarkable fact that yields valuable information about the early universe. Not all pressure is of a sonic nature. Otherwise, gravity waves could be considered as sound. OceanBreeze 1 Quote
OceanBreeze Posted June 17, 2017 Report Posted June 17, 2017 Not all pressure is of a sonic nature. Otherwise, gravity waves could be considered as sound. Assuming you meant gravitational waves, that is an interesting thought. It is a pressure wave and it travels through a medium which is the fabric of space itself. If our ears were sensitive enough, would we be able to hear it? Quote
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