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Why evolution by natural selection didn't make use of RF?

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RJSV:
Humourous thought is an electric EEL trying to fight a ball of aluminum foil....(I'll let readers conjure that up).

   The body's neurological basis is, interestingly, pulse based,  and certainly sounds interesting on a speaker.
I believe it's the firing rate that 'encodes' your intensity.  Had an interesting routine nerve test that the tech had turned up the speaker for a minute.  Seemed like pulses, maybe 10 to 15 per second type in audio play.  Much like short little noisey pulses, 20 mSec est.

EPAIII:
You don't seem to understand the scientific method. Or you are just trying to poke at it.

ALL science is theory. Some theories are better than others, but all are theories. Scientists develop theories to try to explain observations. And then they or other scientists develop ways of testing the theories to see how well they agree with more observations. Those additional observations always ultimately show that any given theory is inaccurate in some respects. The earth is flat. No, it is round. No, it has a somewhat irregular shape. Etc.

And sooner or later all theories are replaced by more accurate theories. No theories ever actually become total fact. They remain theories.

Some theories may be established well enough that some people start to call them laws. But that should not be thought to be true. Even laws of science are ultimately shown to be inaccurate in one way or another. So, even the so-called laws of science are still just theories.

There is no such thing as "scientific fact".

The failure to understand this is the cause of much consternation by the general public and by many of our national and world figures.




--- Quote from: jonovid on August 29, 2023, 05:11:52 pm ---evolution by natural selection is scientific theory, not a fact.
we was made by the creator of the universe.
science struggles with increasing the odds of natural selection in a lab.
the best scientists can do is cut and paste bits of biology with frankenstein like results. :scared:
the kinds are the limit of selective breeding. dog genetics are different from cat genetics so incompatible. so are two different biological kinds.
 experiments adding metal to a biological organism is the stuff of alchemy.   cyborgs are an unnatural freak show.  :palm:

--- End quote ---

EPAIII:
You say those sine waves are not really there.

And yet, they cause interference or noise all across the RF bands. It seems like something is really there.




--- Quote from: RoGeorge on August 31, 2023, 04:47:32 pm ---
--- Quote from: tggzzz on August 30, 2023, 08:41:02 am ---
--- Quote from: karpouzi9 on August 30, 2023, 02:45:51 am ---...
If you subscribe to Fourier's theories, then
...

--- End quote ---

Doesn't everybody?
--- End quote ---

That's far from obvious, nor trivial.  The continuous sinusoids calculated with Fourier are not really there.  The sinusoids are as if it were to be a bunch of added together sinusoids instead of the given shape of a signal, but they are not really there.  One can see with an oscilloscope that there is some other wiggly form and no sinusoid in an arbitrary signal.

A given shape can be decomposed many ways.  One way is to write our shape as a sum of sin and cos functions, thus the Fourier spectrum.  But the same signal can be decomposed, for example, in a series of wavelets.  Or, maybe with some other kernel function instead of either sin/cos or wavelets.

Now, is our arbitrary signal a sum of wavelets?  Or a sum of sinusoids?  Or some other sum of some other kernel functions?

I think the correct answer is neither, our arbitrary signal is just the shape we see on the oscilloscope, not a sum of sinusoids, not a sum of wavelets, or any other sum.


It's a happy coincidence that Fourier is particularly useful in engineering, somehow overlaps with the idea of superposition (which only holds for linear systems).  Then we are all trained to apply Fourier only where it holds, and we turn a blind eye to what doesn't match, or we learn how to minimize Furrier side effects like the Gibbs artifacts, the need of windowing, the lost of causality.

We do that all the time and only consider what we need out of it, up to the point where we start to believe a square wave is made of odd harmonics in a certain ratio, which is not really so.  I consider that's just a form of gaslighting, though this time the gaslighting is just an innocent side effect with no malicious intent behind.  I consider the sinusoidal components aren't really there, and that can be proved in practice.

(An example of causality artifact can be seen in any digital oscilloscope, when sinx/x compensation is on, and the level of a constant 0 or 1 voltage starts to wiggle on the screen before an edge, as if the signal will somehow have premonitions and knows in advance when an edge will come - that's just a Fourier artifact, the logic level can not know the future.)


I think it can be proved in practice that the sinusoids from the Fourier spectrum are not really there.

For example, if we take a square wave of 1kHz, such a signal is supposed to have plenty of sinusoidal 3kHz in it, according to Fourier.  However, one can make a filter that will only respond to a sinusoidal shape of 3kHz, and no other shape than sinusoidal.

Such a 3kHz filter won't respond to a square wave of 1kHz, which indicates there is no sinusoidal 3kHz in our 1kHz square.  I'll say that's a proof Fourier spectrum is not really there.

Now, the funny thing is that what we casually call a 3kHz filter in EE will respond to a 1 kHz square, how so!?!  :o

But then, what's a filter?  And how/why does it work?
That's another simple yet difficult question to answer.

--- End quote ---

TimFox:

--- Quote from: EPAIII on September 02, 2023, 03:49:58 am ---You don't seem to understand the scientific method. Or you are just trying to poke at it.

ALL science is theory. Some theories are better than others, but all are theories. Scientists develop theories to try to explain observations. And then they or other scientists develop ways of testing the theories to see how well they agree with more observations. Those additional observations always ultimately show that any given theory is inaccurate in some respects. The earth is flat. No, it is round. No, it has a somewhat irregular shape. Etc.

And sooner or later all theories are replaced by more accurate theories. No theories ever actually become total fact. They remain theories.

Some theories may be established well enough that some people start to call them laws. But that should not be thought to be true. Even laws of science are ultimately shown to be inaccurate in one way or another. So, even the so-called laws of science are still just theories.

There is no such thing as "scientific fact".

The failure to understand this is the cause of much consternation by the general public and by many of our national and world figures.




--- Quote from: jonovid on August 29, 2023, 05:11:52 pm ---evolution by natural selection is scientific theory, not a fact.
we was made by the creator of the universe.
science struggles with increasing the odds of natural selection in a lab.
the best scientists can do is cut and paste bits of biology with frankenstein like results. :scared:
the kinds are the limit of selective breeding. dog genetics are different from cat genetics so incompatible. so are two different biological kinds.
 experiments adding metal to a biological organism is the stuff of alchemy.   cyborgs are an unnatural freak show.  :palm:

--- End quote ---

--- End quote ---

Science and religion are different:  religion has myths and science has theories.
Those who oppose one or the other think that myths and theories are a bad thing:  both of those groups are wrong.
Myths attempt to explain things, especially their origins, such as creation myths, but they do not have predictive power.
Theories do not explain the purpose of things, but have predictive power;  when a theory's predictions do not agree with experimental evidence, they are to be modified or replaced.
This is a technical forum:  theories are useful.

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