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You've talked about the perils of curve fitting. The experiment is always g oing to have some experimental error, and a good theoretical model isn't go ing to include them. Using enough parameter always let you fit everything, including the noise, but it isn't a useful exercise.

Heisenberg's Matrix mechanics and Schroedinger's wave equations both worked . It took Dirac to demonstrate that they were different embodiments of the same idea.

It's more a question of how many independent parameters you need to model the experimental results. "Easy-to-analyse" doesn't really come into it.

--
Bill Sloman, Sydney
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bill.sloman
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Yes, of course. Every theory has an indeterminate (potentially infinite) number of alternatives; just add any non-observable to a theory and you have a new theory that fits as well as the original one.

And then there's equivalence, which Bill Sloman has pointed out. Isomorphism between theories isn't always easy to spot or to prove.

And then there's quantum mechanics Copenhagen interpretation vs many worlds, etc. Difficult to prove, but that's just it; until there is evidence that favours one or the other, we have no need nor reason to know which is correct.

Clifford Heath

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Clifford Heath

bill.sloman wrote

Not my field, but has my interest, I do seem to remember reading that there are error correcting mechanisms. And redundancy:

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But really (diving into philosophy) if WE humans can design, sure a lower level (if you will 'something' that we are build of, can design..

What we call 'Designing' is just looking for a way forward in -, out of a labyrinth in a way. All your math and all you toys and achievement was formed that way. You see the same behavior in animals, crows for example design their own tools. Published a link to that some time ago.

From that POV John L, is right.

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<698839253X6D445TD

have put error-detecting and error-correcting code into the DNA-to-RNA-to-protein translation machinery.

That wasn't what they were saying. If anything, the way the DNA string gets wound up means that every tenth base pair is more vulnerable to damage than the rest, which would be an error-introducing mechanism - incidental rather than designed in.

Why would you think that? "Design" implies that the "designer" has a target in mind - which is to say a mind.

But it does imply some insight into the structure of the labyrinth.

They weren't formed by throwing dice until a solution that worked came up.

But they don't do selective breeding to produce more ingenious crows.

Sadly, it's a fatuous point of view, based on a rather imperfect grasp of what is going on.

--
Bill Sloman, Sydney
Reply to
bill.sloman

The researchers demonstrate that DNA damage and repair processes can play a role in the generation of sequence periodicity in the genomes of eukaryotic organisms.

You stated that DNA repair processes do not exists, if I did read you right.

No, it is much like water, drop falls on surface, and finds a way, via cracks, channels, etc. As complexity increases from 'drop of water' to micro organisms, the same processes happen. 'life' if you want to call it that, will find a way.

Part of our brain holds what is very much like a 2D map of the solution space, this map if formed by our 'education', and experiences.

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We then build what you could see as a 'view from above' on the labyrinth. That is how I do fault finding, I know what there should be, and the road structure of the labyrinth, recognize each pathway, Knowledge acquired from education and experience.

Same for how I design, very little if anything is 'new' it is just building blocks arranged to form a new castle. Some time you use the building blocks (stones) in a new way, take things from other fields and apply solutions from that. I worked in many fields and the learning process does create that top view of the labyrinth.

The universe (big bang included but likely earlier than that), unfolds that way. You can call it intelligence, it is the same intelligence that makes water from H and O. The path that is possible is taken. That is what I mean with 'intelligence' is inherent to every thing, not only 'life' Life is a result of it, nothing special, and likely everywhere.

Nobody is perfect, but from his viewpoint and my experience if you are honest to yourself, it makes a lot of sense. The ego thing 'we are the [intelligent species]' is just like putting yourself and earth at the center of whatever us speck of dust is in.

Reply to
<698839253X6D445TD

You didn't. I said there wasn't any error-detecting and error-correcting mechanism - with the implication that there were extra check-bits in the DNA string to serve that purpose.

It's well-known that there are mechanisms to repair breaks in the string, but they just put the freed ends back together, not always correctly.

That doesn't happen to be design.

Mindless exploration of the environment isn't design. It can effectively explore a lot of space but isn't systematic and is by no means guaranteed to be comprehensive.

You haven't said anything remotely relevant, or sensible.

Our tools are spectacularly more effective than other species tools. We can reasonably claim to be the premier tool-using species on the planet. To that extent we are at the centre of what we know about.

We can't discuss what we don't know about, but John Larkin keeps trying.

--
Bill Sloman, Sydney
Reply to
bill.sloman

All filter designs need acceptance criteria.

If the incoming SNR = is near 0 dB with the noise 1 freq. decade above the signal ( 50kHz DDR for 5kHz signal ) then 1st you define a spec for:

- output SNR and this SNR improvement ratio.

- bandwidth (-3dB) & gain ripple

- stopband (Hz) & attenuation ( dB) at that f

- max group delay error in passband ( incremental phase shift)

Let's say to want 50 dB SNR output. A 3rd order filter has 60dB/decade.

If you are only putting out a single sinewave then the group delay may not matter.

I find the best design tool is TI's Active Filter

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I can remember what took days in the 70's now takes only a few minutes.

Reply to
Anthony Stewart

But more than one theory can explain current knowledge. None satisfies tomorrow's. How many times has the orbit of Mercury been "finally explained".

Sure. Fit the equations and it all verifies. AGW is explained by computer models. It's done all the time.

Precisely the point.

Reply to
krw

OK, but if there is not any error-detection and error correcting, then there is no repair system possible. I hope you see that?

I strongly suggest that instead of snipping a very relevant link, you actually read it:

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"Navigating our thoughts: Fundamental principles of thinking" It is work from a Nobel winner, still some path to go for you.

Maybe, but you are really good at it 4 sure :-)

Reply to
<698839253X6D445TD

"To be preferred" is your emotional judgement. Being simpler doesn't make it right.

This is an electronic design forum. Designers benefit from considering as many possible architectures or circuits as possible. Brains being massively parallel processors, the energy required to think about a million possible circuits, as compared to the ones that you can find in AoE, isn't the content of one jelly donut.

Any restriction on thinking, like OsR, can leave you in a pool of like-minded people who are offering similar products at race-to-the-bottom pricing.

If two circuits perform the same function, it is often, but not always, better to pick the simpler, or maybe cheaper, one. Simple rules help simple people.

--
John Larkin         Highland Technology, Inc 

lunatic fringe electronics
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John Larkin

If mutation actually drives evolution, critters with perfect error correction will fail to evolve and will encounter other things that have evolved to eat them.

So evolution would pick an optimum mutation rate, to optimize evolution. Or do something even better.

--
John Larkin         Highland Technology, Inc 

lunatic fringe electronics
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John Larkin

The DDS process is complex, but the first important image is -20 dBc at 45 KHz, before filtering.

The easiest acceptance criteria is to simulate the DDS and the filter, and tweak filters until you see something that you like.

I have never got Webench to load and run.

--
John Larkin         Highland Technology, Inc 

lunatic fringe electronics
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John Larkin

There are 2 different things, adaptation of the species, and random mutations,

I know experiments with random mutations due to radioactivity have suggested once in a while something better emerges, but usually not. But the changes due to the intelligence of the things we are build from, cause, over time, adaptation to for example climate changes, other living conditions. Examples are people living at high altitude, people living in polar areas, all have over generations adapted, their bodies have. That is why Africans are black, and us northerns are white for example, sun protection... That is not 'random' at all.

That is a fairy tale, [random] mutations driving evolution, IMNSHO. I think living organisms, like us, or any animal, have the genetic possibility to change their structure map, passed over to the next generation via DNA, sort of pre-design, in fact a simple system, but the being is not normally conscious to this re-design itself.

Same if you drive a car and think of improvements, you change the design and the new one will have those improvements. A very FAST and very SPECIFIC way to adapt. There is a lot more to it, but it would take us way out of 'electronics design' and into how nature designs. There is still a lot to be discovered.

I like to read about those discoveries at the cellular level, there is a lot going on there. I even have a theory memory is stored as DNA or RNA in brain cells. Recent test have shown the effect of changes to RNA on learning and memory:

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<698839253X6D445TD

Neither, of course, does invoking pixies or FSMonsters make /that/ explanation correct. Pixies and FSMonsters are an emotional judgement.

If you are actually interested in the topic, I suggest you slowly and carefully read a /wonderful/ piece of prose and scientific expostion: "The Blind Watchmaker".

That demonstrates why random mutation plus natural selection are sufficient to explain the observed facts.

The main unknown remains, I believe, how DNA came into existence - and there are hypotheses for that. Once DNA (or equivalent!) exists, Darwinian evolution /will/ occur and is sufficient.

Now if you wish to invoke pixies, daemons or FSMs to explain DNA, then I don't have a solid counter-mechanism to refute that. But eventually we will have.

Reply to
Tom Gardner

You really don't understand - or choose not to understand - the concepts and ramifications of random mutation plus natural selection.

Like it has picked an optimum eye design for us. Not!

Not only was the FSMonster a grotty engineer, he didn't even have a lab-book noting more successful "designs". Thus the FSM merely repeated things, badly.

Reply to
Tom Gardner

Not to me. It's pure twaddle.

.any way that we can explain.

No he doesn't. All of those sorts of arguments are complete nonsense. Any argument that declares , well, such and such is too complex to have arose without an intelligent designer fails because such an intelligent designer must be even more complex, so another designer would be required for that designer. Its turtles all the way up.

However, I agree, absolutely that if this universe were the only one, the probability of quarks, electrons, protons, Boltzmans constant, electronic charge, Planks constant, hydrogen, carbon etc all magically conspiring in such a way for us to exist is so low as to be not tenable. Behe gets that bit of the concept correct.

The solution to this issue, does not require a designer. It only needs more lottery tickets to be bought. That is, only someone as naive to believe that the Earth is at the centre of the universe will have trouble in understanding that it is pretty much absurd to believe that whatever physics created this Big Bang, only creates the one.

For example, String Theory pretty much requires 10^500 other universe, all with different laws of physics. More than enough to produce this one.

My take on why the basic laws of Physics in a universe that we have to exist in is here:

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It references err... my other meanderings as to "Something from nothing" and "Universal existence".

Multi-universes is now a main stream idea in physics. Physicist Lawrence Krauss has a book "A Universe from nothing". It's just a fact that stuff gets created from nothing all the time in QM. I explain why above.

It all boils down to this:

Either the solution as to how we are here is that there is either a reason, or there is not a reason. That's it. No other choices possible.

If there is a reason, then the reason for that reason needs to be explained. This is never ending. The only reason that does not need another reason to explain it, is that it is random. That is no reason. I explain why a truly empty universe will generate stuff randomly. Essentially, there are no laws of physics in an empty universe, so there are no laws like conservation of mass-energy to prevent stuff just appearing. You need a reason to explain why stuff don't just appear in an empty universe. All explanations, ultimately resolve to laws of physics. No mass-energy, no laws. Its that simple.

-- Kevin Aylward

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- SuperSpice
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Reply to
Kevin Aylward

Ahhmmmmmm...... you missed the point.

Its obvious that there are hardwired biological algorithms that "want" to survive. We are hardwired to survive and propagate our genes. What is actually necessary in a given environment, programs (software/nurture) what these hardware (nature) algorithms do in order to carry out their "goal".

For example, pre-programming what is or is not edible foods would not be adaptable enough to ensure survival. So, there is an algorithm that seeks out food. What actually tastes good that dives that algorithm is programed. e.g. feed a child spinach, and it grows up liking it.

In the above example, the base algorithms "want" to have babies to propagate their genes. The environment programs the algorithms ways to achieve that goal. i.e. sex...e.g . hookers. Its irrelevant if the algorithms get confused though....

-- Kevin Aylward

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- SuperSpice
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Reply to
Kevin Aylward

The subject started with electronic design, not science. Scientists find existing natural phenomena, and try to explain them. Electronic designers have an unlimited range of architectures and circuits to imagine that don't exist yet.

It would make no sense to drive towards the simplest possible circuit design, and miss all the others that would work too.

There are theories that are so far not contradicted by experiment, and they are in the physics textbooks, generally without cautions about being wrong.

A circuit that works can be sold. What's interesting is to find ones that other people haven't yet found and sold; the economics is better.

Yes. The path to discovery is often roundabout. So let your brain wander around.

Scientists are constrained by peer review and the requirement to publish defensable arguments in standard forms. I have seen physicists be brutal towards colleagues who make mistakes.

There is similar pressure in EE schools, to be analytically precise and to follow accepted forms. An electronic designer just has to create something that pleases him, and ideally pleases customers.

I was invited to be a physicist and declined. Electronic design is fun.

--
John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  
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John Larkin

Insults are not explanations. They aren't even discussion.

--
John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  
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Reply to
John Larkin

e;

do

ly wrong, as in medicine.

idence-based medicine.

do-what-I-was-taught-when-I-was-young system of education, but it is gettin g better. This didn't make it "routinely wrong", but it did make it unfortu nately slow in adopting demonstrably better treatment options.

strably bad treatment options (but mostly to people for whom there aren't a ny good ones).

A triple whoosh in one post!

NT

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tabbypurr

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