Well said.
Yes, when you raise the level of that noise, you have
modulated it... and so you have added information to it.
In the most trivial example, if I was napping in the studio, and I heard the hiss coming from the speakers get louder, I would know someone had moved the control.
And early radio transmissions were accomplished by generating random RF noise using a spark gap - and modulating it on and off with a telegraph key.
And, when I sit at a certain fast food restaurant, I can tell if the ceiling fans are spinning, and how fast, because the blades modulate whatever is coming from the speakers.
(And that works whether they're playing music or all I can hear is background noise... either way it is modulated by the fan blades... which happen to partially block some speakers.)
I'm told that experienced telegraph operators could even extract significant extra information from those simple Morse code signals.
For example, they claimed to be able to tell whether the operator at the other end was tired (by how consistent the timing was on his modulation).
I should also point out that we humans FREQUENTLY use patterns in random noise to obtain useful information.
Didn't you ever listen for the slight jump in the background noise to tell exactly when someone had patched in an extra track?
How about listening for the jump in background noise on a high quality recording of a vinyl album as a way to tell exactly when the needle was dropped?
(In both of those situations you have "extracted useful information by listening to the modulation of random noise"....... )
And, when I'm talking to someone on their cell phone, I can often tell whether their car window is open by listening for traffic noises.
(And it's easy to tell whether they're at home, or on the road, or even sometimes where they are, by analyzing the background noises.)
(It's interesting that, even when I can't hear details, my human brain can still recognize the difference between "restaurant ambience" and "road noise".)
The complicated part is extracting more precise or more detailed information.
The room correction system we use in our lower-end Emotiva gear sends out a burst pattern with a particular envelope.
The system then listens for the signal from each speaker to reach the microphone and uses the time delay to determine speaker distances.
We're playing a known pattern, and using the direct time from the speaker to the microphone, which makes it a easy to decipher.
SONAR, and ultrasonic rangefinders, also both send out their own signal - for the same reason.
If you wanted to do something like that with an unknown signal - like music - where you don't get to generate your own unique signal...
You would have to FIND distinctive pieces of signal.... for example, the distinctive "sort of impulse shaped sound" from a snare drum hit or a tap on a cymbal.
You would probably have to search to find a unique wave-shape.... but, like looking through a window, you wait until you find a signal you can lock onto.
The process is roughly analogous to facial recognition - which attempts to find an approximate match between a known and a bunch of unknowns.
(The system looks at an image, picks out faces, then attempts to determine enough detailed characteristics in one to identify other similar ones.)
Errrrr.....
When a specific source says that "there are challenges to be resolved" - they are stating two things:
1) That THEY have not succeeded in accomplishing the task they're referring to (and don't know of anyone else who has).
2) That, rather than believe it to be impossible, they already have some idea of what they'll have to achieve to make it work.
For example, "there are unsolved challenges that prevent us from sending a live human being to Alpha Centauri".
(But most people I know assume that we will eventually do so... whether it's in twenty years or a thousand.
Note that this is also a "local assertion".
They can only state that they haven't done it... and that nobody they know has done it, admitted to doing it, and provided proof that they've done it.
Neither you, nor I, nor the authors of that paper, know if this has already been done, in some secret project, conducted by the US Navy - or by one of our competitors.
Likewise, the question of whether we can successfully clone a human being, or whether it has already been done, but simply not reported, is considered to be open.
(Beyond a few minor details, we know that current technology has successfully cloned other mammals, and the differences seem likely to only be matters of detail.
There are many reasons for trying to clone a human being, many reasons for publicizing it if you do, and many reasons for keeping it a secret if you succeed.)
Now, as for unicorns..... AS FAR AS I KNOW the US Government hasn't fielded any extensive projects to hunt for them....
However....
- you might be amazed how much money our government, and many others, have spent researching telepathy, and remote viewing, and mind control (unsuccessfully)
- and, during WWII, they had a major project that was based on gluing tiny little incendiary bombs to bats and releasing them over Tokyo (successful but never implemented)
- and we and the Canadians spent a lot of money developing a rather comically unsuccessful flying saucer
- he military are quite often excellent scientists - because they're willing to fund attempts to LEARN THINGS by TRYING to do things that may or may not be possible
And, no, I didn't read it - because I can't see how the opinions of "future directions" by one particular group of scientists would "prove" anything either way (or any way).
(I may eventually read it, as a matter of academic interest, but it certainly isn't going to
prove anything relevant here.)
I can tell you for a fact that I've never funded a project to see if we could accomplish what I suggested...
If someone is interested enough in getting it to work, perhaps someday they will, then we'll know if it's really possible or not...
(at least within the constraints of current technology, the capabilities of the team they hire, and their budget).
Until then, it simply remains conjectural.
1. If I take a piece of random noise and raise it's level by say 6dB, it it still random noise just 6dB louder or has it magically turned into something else? If I take some random noise and change it's level more than once, is it still random noise that's had it's level changed more than once or has it magically become something else? If I take some random noise and change it's level in time with say the beat of a piece of music, is it still random noise or has it magically become something else? Your mistake is in saying the "noise which is correlated to the music", the noise is NOT correlated to the music, if it were, it would not be noise, it would be the music. The random noise is still just random noise, only the level of that random noise changes in time with the music. Could we extract information from this? Yes, we could extract the time/tempo of the music. Could we extract say harmonic information from this random noise? No, it's random noise and by definition does not have any harmonics! Could we extract acoustic information from this random noise? In theory, you could extract the timing of reflections from those amplitude changes, until those amplitude changes fell within the natural amplitude variations of the random noise. In practise though (in the real world), to extract that information we OBVIOUSLY actually need that information to exist in the first place, there must actually be amplitude changes of the random noise that are in response to the reflections. That presents two problems: Firstly, you have NOT provided a single shred of evidence those amplitude changes even exist in the first place and Secondly, even if there were some amplitude changes in the noise that might be caused by reflections, how would you ever be able to determine that in a complex audio mix? We would not be able to relate these hypothetical amplitude changes (in the random noise) to the instrument harmonics causing the reflections because the random noise does not contain any harmonic information (by definition of it being random noise)! In fact, even in the audible band where we definitely have some acoustic information and it's frequency related information (rather than just random noise), STILL it is currently impossible to extract that information! ... It is possible however that you are being "honest". Maybe it's true and you really "
don't even know how to discuss things like this with someone who" ... knows what "correlated" means in terms of an audio signal, has some reasonable knowledge of audio and therefore doesn't accept your assertions of "obviously this" or "it's clear that", just because you say so, especially when the actual evidence effectively says the exact opposite. Maybe you only "
know how to discuss things like this" with audiophiles and others who don't know enough to question/doubt your assertions?
2. If there are still challenges to be resolved in our knowledge of HOW we might accomplish a particular task, then it's self-evident that it's currently impossible to achieve that task. As this is such an easy concept to grasp, I'm finding it difficult to comprehend why you're avoiding grasping it. Actually that's not true, I'm not finding it difficult to comprehend "why" but I'm just not allowed to say
2a. This statement appears to indicate that you can't/don't/won't differentiate "simply an opinion" from an "opinion informed by the facts/science"? (Which could explain many of you contributions to this thread) However, It's a critically important distinction (especially in this sub-forum!). For example, the American government spent hundreds of millions of dollars building a device (LIGO) to detect gravitational waves, the existence of which was an "opinion informed by science" (reliable evidence). However, the American government has not spent hundreds of millions of dollars building a device to detect unicorns, because the existence of unicorns is "simply an opinion" that is uninformed and unsupported by any facts/science. Without this distinction, there is no reason for this sub-forum to exist (or indeed for the vast majority of science itself to exist), it would just be the same as all the other forums and have no relation to science or the facts!
Additionally, I can't see how one can logically argue for an interpretation of a scientific paper (regarding what is currently possible or may/may not be possible in the future), if you haven't even read the paper's section on future areas of research?!
G
