Modeling and measurements. You are welcome to do your own measurements of copper conductors.
Scott I'll assume you mean < -100db distortion! As I routinely use audio runs longer than 1000' the issue really is noise and not distortion. However....
Let me know what you measure on 500 feet of 38 gauge wire made of 99.9% copper, if you can find it, into 600 ohms. Even cheap commercial wire is better than this or it doesn't meet NFPA electrical code standards!
If you take 99.99% copper wire and load it then worst case should be -106 db. Most cable will be better than that by 10 to 20 db. So if you try it let me know if you don't get between -116 and -126 db.
The 99.9% is what standard copper sheets sold in commerce are expected to meet. It is processed to a higher quality before it is drawn into wire.
Wavey, If you actually had diodes or oxide formations in series with the copper in a wire it most likely would break during the drawing process. Then with stranded wire to get all those imperfections to align would be a major challenge!
But there ain't no microdiodes in copper wire!
Pinkmouse I caught that radio 4 show 
Check out the Horizon documentary on the search for the Higgs too if your interested, i'd recommend it. Referring to the "faster than light neutrinos" consider this hypothetically: You can build a theory, that allows particles to exceed the speed of light, so long as the speed of light is a LOWER BOUND for these particles. If a particle is born travelling faster than light, that is fine, but it can't drop below it. This does not prove Einstein wrong at all. There could just be another theory which fills the gap of faster than light travel. Much like how Einsteins relativity theory filled the gap left from Newton on how things behave at speeds approaching c. Let's not worry about the complications behind such a theory, i'm just saying it could exist alongside current theories quite happily.
I see what you mean about approximations DF96, some interesting points you've made. Interestingly, why can't we solve N-body problems? Does that not hint at a limit to our mathematical theories? Hint that there is some aspect that can never be described by theory as we know it. Let me rephrase what I was trying to say before about not having a 100% accurate theory. Consider this: Every particle in the universe, interacts with every other particle in the universe. This interaction is instant, it is not bound by the speed of light, and such is not restricted to particles only within our visible universe, but also outside the horizon. Such properties are termed with the words entanglement, or quantum teleportation. Our understanding is there to some extent, but there is no way we can accurately describe this... in the sense that it all hinges around probability. Yes in our classical world we can accurately predict the movements of objects with intensely small errors. But the real nature behind the universe is inherently Quantum, classical is just the front we see, meaning that no 100% accurate theory can be made. Quantum theory is all about probability. And thus we cannot predict anything with certainty. We make approximations to ignore certain interactions that we think will be negligible, and these work very well for our purposes. But my point was more a thought experiment than anything real-world applicable. It is that, in the end, any theory we make will never describe nature 100%.
A deeper question would be, is probability something we've made up as an approximation? Because the real detail is FAR to complicated to explain in a rigorous mathematical theory? For example, i speculate that if you included the entanglement interaction between every particle in the universe, would this get rid of the need for probability? And provide us with a theory that basically means we can predict anything with certainty?
Is it theoretically possible to build a robot that can predict everything/know everything? If so, I highly doubt he could answer as simple a question as, "what is your favorite painting?", the robot would see the question as meaningless. He may be able to answer which painting is best technically, but not his favorite. If this robot knew your entire life history, would he be able to predict your next move? Just some interesting thoughts to ponder if your interested.
String theory is a hard one... How much do you know about it? You think it's just a wild stab in the dark? I can show you some things which would really change that opinion, I hope. We know the standard model is wrong as we currently see it. Fact. I can link you to some really nice online lectures that talk about it and look at how SUSY and Strings provide answers where the standard model can't. Though they are kind of at graduate/PhD level, you can still get the gist of them if you can't follow the maths. SUSY and Strings predict some really powerful things but kind of rely on the experiments to look for these things now... I don't think that is a bad thing.
People are doing experiments to search for extra dimensions/investigate black holes at CERN. This is possible because of theory work on SUSY and Strings. The experiments couldn't of been done without the theory framework there beforehand. I can only think that this is a good thing, even if the outcome is that some theory is ruled out?
Let me try and explain why is String theory a logical step forward from our previous way of thinking. String theory describes the world as being made up of bits of 1-Dimensional strings that can vibrate - these are of order the Plank length. Previously, our theories have only looked at electrons & quarks etc as 0-dimensional objects within atoms. Basically that the fundamental bits of matter are particles. (Yes i stole that from wiki, but I can't be bothered to dig out my lecture notes right now for a better brief description!). As we know the standard model is wrong, does String theory not propose a very intelligent way forward to try and understand things in a different manor? It's not a wild stab in the dark, it is a very logical step in speculating new physics, going from 0d unit entities (particles), to 1d unit entities (strings). 1d is considerably more complicated than 0d, but as our simple theory for 0d objects hasn't worked out to our hopes and dreams so far(!), surely it's time to consider more complicated 1d objects? Read the wiki on it, it will tell you some of the things it predicts that no other theory can right now. And it ties together many different aspects of physics that we've previously been unable to unify or correlate. Even if it is still wrong, there is not much else that is quite as good at fitting everything together, so i'm sure it's a healthy way to think about things for now anyway.
Check out the Horizon documentary on the search for the Higgs too if your interested, i'd recommend it. Referring to the "faster than light neutrinos" consider this hypothetically: You can build a theory, that allows particles to exceed the speed of light, so long as the speed of light is a LOWER BOUND for these particles. If a particle is born travelling faster than light, that is fine, but it can't drop below it. This does not prove Einstein wrong at all. There could just be another theory which fills the gap of faster than light travel. Much like how Einsteins relativity theory filled the gap left from Newton on how things behave at speeds approaching c. Let's not worry about the complications behind such a theory, i'm just saying it could exist alongside current theories quite happily. I see what you mean about approximations DF96, some interesting points you've made. Interestingly, why can't we solve N-body problems? Does that not hint at a limit to our mathematical theories? Hint that there is some aspect that can never be described by theory as we know it. Let me rephrase what I was trying to say before about not having a 100% accurate theory. Consider this: Every particle in the universe, interacts with every other particle in the universe. This interaction is instant, it is not bound by the speed of light, and such is not restricted to particles only within our visible universe, but also outside the horizon. Such properties are termed with the words entanglement, or quantum teleportation. Our understanding is there to some extent, but there is no way we can accurately describe this... in the sense that it all hinges around probability. Yes in our classical world we can accurately predict the movements of objects with intensely small errors. But the real nature behind the universe is inherently Quantum, classical is just the front we see, meaning that no 100% accurate theory can be made. Quantum theory is all about probability. And thus we cannot predict anything with certainty. We make approximations to ignore certain interactions that we think will be negligible, and these work very well for our purposes. But my point was more a thought experiment than anything real-world applicable. It is that, in the end, any theory we make will never describe nature 100%.
A deeper question would be, is probability something we've made up as an approximation? Because the real detail is FAR to complicated to explain in a rigorous mathematical theory? For example, i speculate that if you included the entanglement interaction between every particle in the universe, would this get rid of the need for probability? And provide us with a theory that basically means we can predict anything with certainty?
Is it theoretically possible to build a robot that can predict everything/know everything? If so, I highly doubt he could answer as simple a question as, "what is your favorite painting?", the robot would see the question as meaningless. He may be able to answer which painting is best technically, but not his favorite. If this robot knew your entire life history, would he be able to predict your next move? Just some interesting thoughts to ponder if your interested.
String theory is a hard one... How much do you know about it? You think it's just a wild stab in the dark? I can show you some things which would really change that opinion, I hope. We know the standard model is wrong as we currently see it. Fact. I can link you to some really nice online lectures that talk about it and look at how SUSY and Strings provide answers where the standard model can't. Though they are kind of at graduate/PhD level, you can still get the gist of them if you can't follow the maths. SUSY and Strings predict some really powerful things but kind of rely on the experiments to look for these things now... I don't think that is a bad thing.
People are doing experiments to search for extra dimensions/investigate black holes at CERN. This is possible because of theory work on SUSY and Strings. The experiments couldn't of been done without the theory framework there beforehand. I can only think that this is a good thing, even if the outcome is that some theory is ruled out?
Let me try and explain why is String theory a logical step forward from our previous way of thinking. String theory describes the world as being made up of bits of 1-Dimensional strings that can vibrate - these are of order the Plank length. Previously, our theories have only looked at electrons & quarks etc as 0-dimensional objects within atoms. Basically that the fundamental bits of matter are particles. (Yes i stole that from wiki, but I can't be bothered to dig out my lecture notes right now for a better brief description!). As we know the standard model is wrong, does String theory not propose a very intelligent way forward to try and understand things in a different manor? It's not a wild stab in the dark, it is a very logical step in speculating new physics, going from 0d unit entities (particles), to 1d unit entities (strings). 1d is considerably more complicated than 0d, but as our simple theory for 0d objects hasn't worked out to our hopes and dreams so far(!), surely it's time to consider more complicated 1d objects? Read the wiki on it, it will tell you some of the things it predicts that no other theory can right now. And it ties together many different aspects of physics that we've previously been unable to unify or correlate. Even if it is still wrong, there is not much else that is quite as good at fitting everything together, so i'm sure it's a healthy way to think about things for now anyway.
Oh one more point, I can't find the literature atm (ill look harder another time) but take my word on this for now: Scientists discovered what i think was a new K Meson state ( it could have been a new K meson, or different particle excitation state... I will try and find it later, but i'm really not trying to fool you guys, the details don't matter really). It was written into texts books and got good peer reviews across the board. This was around 1999. In 2004 (i think it was) some new physics was discovered which invalidated this new particle state that was discovered. It turns out it was completely wrong, and was shown to be something completely different. This is just one of the major examples of how scientific fact can easily become fiction. If i find the details i'll show you, promise.
Ed what are you talking about, at one point you say .01% distortion and then you just babble on with a pile of obfuscation. So cut the BS I want to unroll about 1 Ohm of solder and make a 1:1 divider with a 1 Ohm resistor and measure (I assume) no distortion.
I remember reading somewhere Newton himself, where he clearly stated that he does not know where that 2'nd order law comes from, he just found that it exists and accepted it, and he did not have any theory to explain why it happens, but he knows that it happens.
It means clearly, that so called Newtonians are against Newton himself protecting "Newtonian" physics that actually is not Newtonian at all.
Entanglement and teleportation are not the same thing.
SUSY and string theory do not provide answers (yet), at best they pose questions. My hunch is that SUSY is more likely, but that is just a gut feeling based on prejudice. String theory has too many parameters, so has little predictive power. It has become a playground for mathematicians who can kid themselves they are doing physics. We must remember that the Higgs has not yet been confirmed, although looking more likely now, so the Standard Model still has one piece missing. I once met Peter Higgs. He was a guest lecturer at the 1976 British summer school for particle physics at Southampton university. I happened to sit opposite him at lunch that day (I was a lowly first year postgrad).
Particle resonances and other excited states come and go. Identification can be messy, so not surprising that this sometimes gets changed later on. You are basically looking for wiggles in a differential cross-section, and doing a least-squares fit based on kinematics to get an idea of spin state. I did that for pion resonances back in 1976. I think I found three candidates, but I have no idea if they are now in the official tables.
SUSY and string theory do not provide answers (yet), at best they pose questions. My hunch is that SUSY is more likely, but that is just a gut feeling based on prejudice. String theory has too many parameters, so has little predictive power. It has become a playground for mathematicians who can kid themselves they are doing physics. We must remember that the Higgs has not yet been confirmed, although looking more likely now, so the Standard Model still has one piece missing. I once met Peter Higgs. He was a guest lecturer at the 1976 British summer school for particle physics at Southampton university. I happened to sit opposite him at lunch that day (I was a lowly first year postgrad).
Particle resonances and other excited states come and go. Identification can be messy, so not surprising that this sometimes gets changed later on. You are basically looking for wiggles in a differential cross-section, and doing a least-squares fit based on kinematics to get an idea of spin state. I did that for pion resonances back in 1976. I think I found three candidates, but I have no idea if they are now in the official tables.
Entanglement can provide a way to teleport quantum information, you can know about the state of another particle before light has time to reach it (supposedly), that's all i meant by it. Indeed the Higgs particle seems to be on the verge of discovery (or being ruled out)... but that doesn't fill in all the gaps in the standard model. It's still wrong. One worrying thing is that certain SUSY particles that "should" have been seen by now haven't... however, there are other versions of SUSY where this is fine. So it's all up for grabs at the moment. I still think string theory has a shot, why shouldn't it be so complicated? nature is very complicated... why should we only search for theories with very few parameters which imply only one version of a theory? We are trying to create a theory that encompasses everything, that it quite a challenge, right! yes there are so many versions of string theory (most incorporating SUSY happily), but that may just be because we aren't clever enough to work out what one is correct. Maybe it's to do with why the parameters in our universe so fine tuned... There is nothing else around atm that does anything like what string theory does, i think it's quite impressive whether it's right or wrong. Anyhow I think exciting things are going to happen over the next decade or two - if strings (or even susy as well) are shown to be wrong or just a silly playground of mathematics, i'm sure there will be quite an uproar/panic period among scientists.. To be honest i secretly hope this happens just for comical value!
Not exactly, at some level information is energy (I forgot the article where someone bounded the minimum energy of a "bit") so there is no teleportation of information, when the entanglement collapses all information is lost.
There are a least two startups here selling quantum encryption hardware.
No. Unlike most people, scientists enjoy (at least in theory) being proved wrong because that means there is something new to be discovered. I say "in theory" because scientists are people too, and can sometimes get emotionally attached to their ideas.
I think you may be right that an exciting time in physics is about to arrive. It was fun back in the 1970s. I remember the J/psi being discovered, so we had to add charm to strangeness. Now we have six quarks and six leptons, and reason to believe that may be the lot (at least for conventional matter). People are now trying to both confirm the Standard Model and break it. It is likely that any 'breaking' will be an extension, although journalists will no doubt proclaim that the old theory was 'wrong'.
Journalists keep looking for headline-sized (not even tweet-sized!) answers when scientists try to tell the whole story. Thus I've heard people say "scientists don't know what they're doing, they can't even make up their minds - one day they say eggs are good for you, another day eggs are bad for you" when it's really journalists who are to blame.
"Egg whites good, egg yolks bad."
Ah, it makes sence. Slicing and smoking is bad, I know now.
But how can it be bad if it is tastier?
We have evolved to eat cooked food because it makes for more efficient digestion of energy producing material and of other nutrients. That's why roasted and smoked meat tastes good.
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How "bad" it might be for you probably depends on processing and cooking temperatures..... WAG
It is a superstimulus. Same reason certain beetles like to have sex with beer bottles - the bottle looks to them like a very large (and fertile) female beetle. Beetles often die trying to impregnate the bottles, but bottles produces no eggs.
In nature salt, sugar and fat are important but scarce nutrients, so we are attracted to foods that contain them. Modern junk food contains too much of those ingredients, so taste nice but are not healthy.
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