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Astronomically Theoretical Experiment
Record a sound at 10^-500 of an attobel in mono into an optical (using
lasers) device. Convert the analog optical signal to digital optical PCM channel (still mono). This digital PCM signal should remain mono and should have a sampling rate of 10^500 samples every attosecond, and a bit-resolution of 10^1,000-gigabit. This high-quality mono PCM signal should be split into 100^10,000 different audio channels, this will reduce the loudness immeasureably. This 100^10,000 channelled, 10^500 sampled per attosecond, 10^1,000 gigabit PCM audio should be amplified from 10^-500 of an attobel to 20 decibels. Remember that this a purely optical device using UV lasers for the purposes of A-D conversion, D-A conversion, recording, playback, storage, transmission, reception, and processing of sound. What will the recording sound like when played back? |
#2
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Astronomically Theoretical Experiment
In article ,
Radium wrote: Record a sound at 10^-500 of an attobel in mono into an optical (using lasers) device. Convert the analog optical signal to digital optical PCM channel (still mono). This digital PCM signal should remain mono and should have a sampling rate of 10^500 samples every attosecond, and a bit-resolution of 10^1,000-gigabit. This high-quality mono PCM signal should be split into 100^10,000 different audio channels, this will reduce the loudness immeasureably. This 100^10,000 channelled, 10^500 sampled per attosecond, 10^1,000 gigabit PCM audio should be amplified from 10^-500 of an attobel to 20 decibels. Remember that this a purely optical device using UV lasers for the purposes of A-D conversion, D-A conversion, recording, playback, storage, transmission, reception, and processing of sound. What will the recording sound like when played back? Okay, first, you have some confusion with units. 10^-500 attobels is almost exactly equal to 0 attobels. If you mean something which is 10^500 times smaller than an attobel, well, that's -500 attobels. Beyond that, you are FAR below the level at which quantum uncertainty completely dominates. That has pretty serious implications on your gedanken. For example, if you're talking about such miniscule sound pressure level variations, you're talking about detecting displacements that are far smaller than the constituents of the atomic nucleus. Describing such phenomenon in the context of sound, which is a manifestation at the macro level, is essentially meaningless. Further, the very techniques you are wanting to use to measure these things, lasers and such, are GROSSLY inadequate to the task. Uncertainty itself prevents you from even getting there. You want to measure phenomenon of VERY low energy over VERY small distances: that means you want extremely high certainty of both position and momentum, whicb is simply forbidden by uncertainty. Tou measure things over small distances, uncertainty requires very high uncertainty in momentum, which means very high energy, and vice versa. Another significant stumbling block: the simple thermal energy of air alone generates a sound pressure whose broadband equivalent noise level is not very much below the threshold of hearing, so simple thermal agitation itself will TOTALLY overwhelm anything at the levels your are contemplating. Assume you are trying to see what's going on at one attobel, or -340 decibels: the thermal noise is somehwre in the realm of 320 dB higher. Assume you want to divide, as you say, into many individual channels (I assume you mean frequency bins), you are bitten again by the uncertainty principle (this time the time-frequency uncertainty). Divide the audio spectrum (20 kHz) into a google channels (10^100): the response time of each channel is now 10^100/20,000 or 5*10^95 seconds, much longer than the age of the universe (estimated at about 10^18 seconds), much longer than GUT estimates of the half life of protons (10^28 seconds) and, if GUT theories are correct, much longer than ordinary matter will exist and thus the projected age of the universe. So, by the time half of the mass of the universe had decayed, you'd have NO signal coming out of your analyzer yet. What would it sound like we COULD? Well, that much we know: noise. Ordinary noise with gaussian distribution. We'd be listening to the simple noise of air due to random impacts of air molecules against the detector due to thermal agitation at a level that is 340 dB higher than what you'r looking for. -- | Dick Pierce | | Professional Audio Development | | 1-781/826-4953 Voice and FAX | | | |
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Astronomically Theoretical Experiment
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#4
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Astronomically Theoretical Experiment
In article ,
Radium wrote: (Richard D Pierce) wrote in message ... For example, if you're talking about such miniscule sound pressure level variations, you're talking about detecting displacements that are far smaller than the constituents of the atomic nucleus. Describing such phenomenon in the context of sound, which is a manifestation at the macro level, is essentially meaningless. Further, the very techniques you are wanting to use to measure these things, lasers and such, are GROSSLY inadequate to the task. Even when digital? The "digital" issue is irrelevantm,: digital is simply a notation of convenience or lack thereof for the data. The problem is, no matter how you represent the data, you CAN'T GET the data to the desired precision to begin with: you are up against the fundamental physical limitations imposed by uncertainty. And we are not talking of the inability to measure because of uncertainty, i.e., the inability to measure both the position and energy of an object with perfect certainty, we are talking about the fact that an object simply cannot have a simultaneously precise position and energy, period. Uncertainty itself prevents you from even getting there. You want to measure phenomenon of VERY low energy over VERY small distances: that means you want extremely high certainty of both position and momentum, whicb is simply forbidden by uncertainty. Tou measure things over small distances, uncertainty requires very high uncertainty in momentum, which means very high energy, and vice versa. Another significant stumbling block: the simple thermal energy of air alone generates a sound pressure whose broadband equivalent noise level is not very much below the threshold of hearing, so simple thermal agitation itself will TOTALLY overwhelm anything at the levels your are contemplating. Assume you are trying to see what's going on at one attobel, or -340 decibels: the thermal noise is somehwre in the realm of 320 dB higher. Assume you want to divide, as you say, into many individual channels (I assume you mean frequency bins), you are bitten again by the uncertainty principle (this time the time-frequency uncertainty). No. Channels are the available different locations of the audio signal. That is: 1 channel = mono 2 channels = stereo Divide the audio spectrum (20 kHz) into a google channels (10^100): the response time of each channel is now 10^100/20,000 or 5*10^95 seconds, much longer than the age of the universe (estimated at about 10^18 seconds), much longer than GUT estimates of the half life of protons (10^28 seconds) and, if GUT theories are correct, much longer than ordinary matter will exist and thus the projected age of the universe. So, by the time half of the mass of the universe had decayed, you'd have NO signal coming out of your analyzer yet. What would it sound like we COULD? Well, that much we know: noise. Ordinary noise with gaussian distribution. We'd be listening to the simple noise of air due to random impacts of air molecules against the detector due to thermal agitation at a level that is 340 dB higher than what you'r looking for. Shouldn't digital audio with a sufficiently strong bit-resolution and high sampling rate have natural protection against noise? No, you don't understand, you are asking to determine the property of a system precisely where the system DOES NOT and CANNOT HAVE the precision you ask for. Even if I were to hypothesize PERFECT A/D conversion of the needed resolution, the very thing I am measuring wimply CANNOT HAVE the kind of properties you desire them to. Digital has NOTHING to do with it. Let's make a microphone diaphragm out of a single proton, for example. The sound level you are trying to measure causes changes in the proton's state. You want to measure that state. The simple and inevtiable fact is that you CAN NEVER measure, simultaneously, the protons position and its energy to precise values because a proton CANNOT HAVE simultaneously a precisely defined energy and a precisely defined position. These are fundamental limitations imposed by physics, not by practical implementations. Here's where your experiment falls apart in a very strange way. You may choose to ignore the energy portion, and simply measure where the proton is from moment to moment. But, by definition, since movement of the proton between two moments defines implicitly the lower limit of the uncertainty of its energy, (since the change in position in time is the proton's velocity and, in the simple case, the energy is the proton's mass times the square of its velocity), you simply will never be able to measure the position itself to the level of precision you desire. It's not intuitive, and there's no reason for it to be intuitive. Once again, HOW you represent the numbers makes NO difference: you are forbidden by the very nature of the problem from ever getting the numbers you want. -- | Dick Pierce | | Professional Audio Development | | 1-781/826-4953 Voice and FAX | | | |
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