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Is physics about "why?"


newts
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One can argue that physics says noting about "why".

 

Physics is all about why. Why do electric currents flow? Because electrons and protons attract their like, and repel their unlike. Maxwell may have done some handy maths, but he still could not have answered that basic question, because electrons and protons had not been discovered in his time.
But surely the biggest question in physics today is: why have physicists stop trying to make sense of the universe, and instead started to believe it is all mystical and mysterious, and can only be understood through maths, and invented more imaginary beings than anybody since the Ancient Greek mythologers
Edited by newts
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Physics is all about why.

No it isn't. Philosophy is all about the why. Physics is making the most accurate predictions possible. The two are not automatically divorced, but the why is in no way a prerequisite or 'all' physics needs to make predictions.

 

In fact, the example you use supports this! Maxwell's equations got attention because they made such darn good predictions. They still do, for that matter. But the why is not in there, and it is not needed. Physics is looking for the model that makes the largest number of accurate predictions.

 

But surely the biggest question in physics today is: why have physicists stop trying to make sense of the universe, and instead started to believe it is allmystical and mysterious, and can only be understood through maths, and invented more imaginary beings than anybody since the Ancient Greek mythologers

As above, I don't think that physics and philosophy is automatically divorced, and in many ways I think a great number of physicists are trying their best to make sense of the universe.

 

I think that there is some real conceit in the quote above, because it seems to imply that the universe is under some kind of obligation to be understood at some level. And really, why pick the 'I don't understand math' level? Why not pick 'comprehendable via the average kindergardener's vocabulary'? Heck, why stop there... let's pick 'comprehendable via gestures and grunts alone'!

 

My point is that wherever you arbitrarily draw the line, there is always going to be some group that will be unable to comprehend it. And I don't think that there is an unfairness inherent in this. No everyone will understand everything.

 

At this moment, the models that make the most accurate predictions about how the Universe acts requires some fairly hefty mathematics to understand. I guarantee that everyone who works on it wishes it was simpler. But there is very, very limited value in a simple model that makes poor predictions -- most often only used as a teaching aide to then subsequently introduce the more complicated but more accurate model. If someone doesn't understand that more complicated model, so be it. I will take more accurate prediction every single time, no matter the level of complexity.

 

As for your imaginary beings, I know you have a personal problem with quarks and other of the current physics models. Models, by the way, that have made outstandingly excellent predictions that agree very, very closely to measurements. As in your threads, all you have to do to rid physics of these beings you consider imaginary is to demonstrate a model that makes even more accurate predictions. It really is that simple. Greater and more accurate predictions. You had a very long thread in which you were given many, many chances to do this, and failed.

 

If one wants to talk imaginary, let's talk about your so-called better model, shall we?

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Physics is all about why.

Physics is really all about mathematical models and how these compare with nature. The best one can do to attempt to get close to a "why" is really in the mathematics of understandig "how". I think the "whys" and "hows" get confused in general conversations about physics.
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I think that there is some real conceit in the quote above, because it seems to imply that the universe is under some kind of obligation to be understood at some level.

 

 

My point is that wherever you arbitrarily draw the line, there is always going to be some group that will be unable to comprehend it. And I don't think that there is an unfairness inherent in this. No everyone will understand everything.

 

 

As for your imaginary beings, ..................... You had a very long thread in which you were given many, many chances to do this, and failed.

 

The only reason the universe seems incomprehensible is that humans are too stupid to make sense of it; things like lightning, rainbows and tides, were once mysteries but now we have proper explanations.
The problem is that physics-believers believe in the omniscience of modern physicists; so if something lacks a rational explanation they believe it must be the universe’s fault, because they cannot accept the ignorance of the experts, and so they assume the universe must be mysterious and mystical.
Physics-believers like to believe that they are intellectually superior to non-believers. But the fact is that proper theories can always be explained in words even to simpletons. The difficult part is coming up with a correct theory in the first place. Anybody can be taught that the earth is just a collection protons neutrons and electrons; but nobody could have ever figured that out without brilliant experiments and mathematical analysis.
The idea that some theories can only be understood with maths, is just physics-believers’ excuse to believe in nonsense. Nobody can explain the Higgs field, because it is meaningless rubbish. It is supposed to give particles mass, but it is completely useless for predicting the mass of particles, therefore it is not a scientific theory. The only thing the Higgs field did predict was the existence of one or more particles within a mass range of several hundred percent. A physics-believer might describe that as “a model that makes the most accurate predictions about how the Universe acts”, but a non-believer might beg to differ.
Go to a creationist website, and teach them to accept evolution. Convince a group of astrologists that astrology is bunk. Then criticise my failure.
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I can argue back (without using maths as well) that the answer

importantly is "Yes", since light can be made using an electron and

positron, or light can be made using a proton and an anti-proton.

 

 

 

Excellent logic. But you need to bear in mind that physics-believers do not believe in logic, they believe in imaginary beings, so they would argue that protons are made of quarks, but electrons are not, therefore your hypothesis is wrong.

 

Then somebody should come and say that:

- pion 0 is supposed to be made of quarks, but it's decaying to 2 gamma photons, or other time decaying to electron and positron and gamma photon.

- pion+ is supposed to be made of up quark and antidown quark, but it's decaying to muon+ and muon neutrino, or other time decaying to positron and neutrino, and other time to pion 0, positron and neutrino..

(etc. etc. countless examples of decay modes)

 

And then interlocutor, usually mod, will press negative arrow on such post.. wink.png

Edited by Przemyslaw.Gruchala
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Go to a creationist website, and teach them to accept evolution. Convince a group of astrologists that astrology is bunk. Then criticise my failure.

So... you're throwing yourself in with the creationist and astrologists? That explains a lot, actually. Not sure why you'd bother trying to post on a science website then, but... whatever.

 

newts, you have posted yourself that you don't understand the math behind modern physics (I can find that post in your old threads if you've forgotten this). Criticizing things you don't understand kind of just makes you look foolish, especially when there is no need to do so. Admitting that you don't understand something is perfectly fine. No one knows everything. But trying to tear down something you don't understand just casts you into the same lot as the religous nuts you talk about above.

 

But the fact is that proper theories can always be explained in words even to simpletons.

Why is this a 'can always'? Under what obligation is any theory to be understandable to anyone of any intelligence level?

 

I think that this idea is complete and total rubbish. And you provided absolutely no reason why any theory, idea, or the Universe is under any obligation to be explainable.

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newts, I have one more comment based on a conversation I had today.

 

And it is a simple cliched statement, but it rings very true:

 

You don't know what you don't know.

Edited by Bignose
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So... you're throwing yourself in with the creationist and astrologists? That explains a lot, actually. Not sure why you'd bother trying to post on a science website then, but... whatever.

Not to say that I support newts and his theory, but he's throwing physicists in with creationists and astrologists, and pretending that he's the skeptic of both creationism and astrology.

=Uncool-

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But surely the biggest question in physics today is: why have physicists stop trying to make sense of the universe, and instead started to believe it is all mystical and mysterious, and can only be understood through maths, and invented more imaginary beings than anybody since the Ancient Greek mythologers

 

!

Moderator Note

Another big question is why you continue to hijack threads in order to complain about physics. You've been told to stop

 

Then somebody should come and say that:

- pion 0 is supposed to be made of quarks, but it's decaying to 2 gamma photons, or other time decaying to electron and positron and gamma photon.

- pion+ is supposed to be made of up quark and antidown quark, but it's decaying to muon+ and muon neutrino, or other time decaying to positron and neutrino, and other time to pion 0, positron and neutrino..

(etc. etc. countless examples of decay modes)

 

And then interlocutor, usually mod, will press negative arrow on such post.. wink.png

 

!

Moderator Note

And here we have another example of hijacking to complain about some aspect of physics, instead of containing the discussion to its own thread, as the rules demand.

 

 

Both by someone who has been told repeatedly to stop, and been suspended before as a result.

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Not to say that I support newts and his theory, but he's throwing physicists in with creationists and astrologists, and pretending that he's the skeptic of both creationism and astrology.

=Uncool-

My point was that getting people to change their opinions is never easy. Sceptic is too weak a word to describe my attitude to creationism or astrology; but I am a mainstream physics sceptic, because I know some of it be excellent, some fantasy, and much I am still unsure of.

 

Why is this a 'can always'? Under what obligation is any theory to be understandable to anyone of any intelligence level?

As Einstein is supposed to have said “if you really understand something you can explain it to your grandmother“. For Higgs-believers to claim that they understand how nature works, but that they cannot explain the theory to non-believers because they are not clever enough, just does not wash. Renaissance mathematicians had their mathematical theory of epicycles that predicted planetary orbits quite accurately, but they could not really explain it in words because it was nonsense. However just anybody can understand the idea that the sun’s gravitation pull causes planets to follow a curved path through space.

Edited by newts
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As Einstein is supposed to have said “if you really understand something you can explain it to your grandmother“. For Higgs-believers to claim that they understand how nature works, but that they cannot explain the theory to non-believers because they are not clever enough, just does not wash. Renaissance mathematicians had their mathematical theory of epicycles that predicted planetary orbits quite accurately, but they could not really explain it in words because it was nonsense. However just anybody can understand the idea that the sun’s gravitation pull causes planets to follow a curved path through space.

Appeal to authority (Einstein) is a logical fallacy.

 

And just because you have a single example, gravity, that you have decided is easy enough to explain to someone -- still a completely arbitrary scale, be it a grandmother or a simpleton) -- that doesn't mean that all examples should be easily explainable. And, really, there is nothing that precludes a grandmother from knowing a level of mathematics sufficient enough to understand modern physics. Do you see how these levels are completely arbitrary? This is what happens when someone just decides that something should be so.

 

Furthermore, to be extremely pedantic, modern physics actually doesn't have why gravity works. We have proposed ideas like the graviton, but no gravitons have been detected to date. So, you in fact have picked as your example of something simple enough to explain and understand as something we don't have a complete explanation and understanding of. Kind of ironic, really.

 

What we do have is an excellent model of gravity in that we can make very accurate predictions of how the gravity force affects objects.

 

Lastly, I think it should be said that epicycles weren't rejected because the were 'nonsense'. They were ultimately rejected because as better telescopes and records were kept of the motion of the things mankind saw in the sky, the predictions made by the epicycle model were shown to be worse and worse. Where as the heliocentric model was making predictions that were being found to be more and more accurate. Near the end of the epicycle model, they were adding epicycles within epicycles 2, 3, 4 layers deep to attempt to make predictions that agreed with measurements. But ultimately it was given up because the math just wasn't agreeing.

 

My point was that getting people to change their opinions is never easy. Sceptic is too weak a word to describe my attitude to creationism or astrology; but I am a mainstream physics sceptic, because I know some of it be excellent, some fantasy, and much I am still unsure of.

I am not sure this is especially profound. We actually know with 100% certainty that our models today are wrong, in that they are at least incomplete. Whether you want to describe that as 'fantasy' or not, well that's a word choice I don't think I would have made, but to each their own.

 

What really irritates me, newts, is your lack of respect for known confirmed data. Whether you think quarks are fantasy or not, it is undeniable that the quark model as it exists today makes predictions that agree pretty darn well with experimental data. And whatever model replaced, supplants, or enhances the quark model will also make predictions that agree really well with experimental data. If the replacing, supplanting, or enhancing idea didn't, it would be rejected outright as demonstrably less useful.

 

Unless you can show that all the experimental data that currently agrees with the quark model has been falsified in some way, you cannot just wave it away. So if you want to promote what you think is a better model, just show that it makes better predictions. Make a plot with current measured values, the predicted values of today's model, and the predicted values from your model to demonstrate that your model is more accurate than any other one out there.

 

It is just that simple, newts.

Edited by Bignose
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My point was that getting people to change their opinions is never easy. Sceptic is too weak a word to describe my attitude to creationism or astrology; but I am a mainstream physics sceptic, because I know some of it be excellent, some fantasy, and much I am still unsure of.

Yay, another baseless attack on mainstream physics. Please, save it until you have something new - like actual evidence for your idea.

As Einstein is supposed to have said “if you really understand something you can explain it to your grandmother“.

See, the funny thing is, it's not that hard to explain quantum field theory - just very, very time-intensive and math-intensive. The problem is that people like you are unwilling to learn even the first step towards it, either on the physics side or on the math side.

For Higgs-believers to claim that they understand how nature works, but that they cannot explain the theory to non-believers because they are not clever enough, just does not wash. Renaissance mathematicians had their mathematical theory of epicycles that predicted planetary orbits quite accurately, but they could not really explain it in words because it was nonsense.

You really shortchange supporters of epicycle theory. A is going around B while B is going around C is really easy to explain.

 

=Uncool-

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As Einstein is supposed to have said if you really understand something you can explain it to your grandmother.

Here's a great example of why that isn't necessarily true

 

 

Are you saying Richard Feynman didn't understand magnets because he couldn't explain it to this person?

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Furthermore, to be extremely pedantic, modern physics actually doesn't have why gravity works. We have proposed ideas like the graviton, but no gravitons have been detected to date. So, you in fact have picked as your example of something simple enough to explain and understand as something we don't have a complete explanation and understanding of. Kind of ironic, really.

Newton did not explain what caused gravity, but he did simplify the solar system by showing that tidal forces are just differential gravity. Likewise we now know that the strong nuclear force is just differential electric forces. The aim should be to reduce the number of forces in the universe as low as possible; which could be down to only 1, but that 1 force could have no proper explanation.

 

You really shortchange supporters of epicycle theory. A is going around B while B is going around C is really easy to explain.

 

Epicycles might be simple for great minds like yourself and Bignose. But if I had to explain planetary orbits to a female, I would sooner do so by pushing a pendulum so it swings in a circle, rather than have to screw a gramophone to a roundabout and then try to convince her that space contains comparable structures.

 

Are you saying Richard Feynman didn't understand magnets because he couldn't explain it to this person?

 

No, what I would say is that Feynman could not explain magnetism because he did not really understand it, but it is an interesting clip. I do admire Feynman, he understood a lot and did his best to share his understanding; unlike today’s celebrity physicists who understand little, and try to mysticise the universe.
Given physicists’ current understanding, it would seem reasonable to say that electrons repel each other and attract positrons, merely because it is in their nature to do this. But clearly magnetism is not a fundamental force. Lay 2 wires side by side, there is negligible force between them, pass currents in the same direction the wires attract, pass currents in opposite directions they repel. These forces are described as magnetic, therefore at least some magnetic forces must be caused by electric currents or the motion of electrons. It also inclines me to think that, contrary to popular belief, magnetic forces should really be described as like attracting like, and repelling unlike.
Is anybody interested in the cause of magnetism, or is that too mundane for modern physicists?
Edited by newts
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Newton did not explain what caused gravity, but he did simplify the solar system by showing that tidal forces are just differential gravity. Likewise we now know that the strong nuclear force is just differential electric forces.

Source, please. Something other than your site.

The aim should be to reduce the number of forces in the universe as low as possible; which could be down to only 1, but that 1 force could have no proper explanation.

Why? Why shouldn't the aim be to find accurate models, and only once that's done to find the simplest model?

Epicycles might be simple for great minds like yourself and Bignose.

I just gave the simple explanation. It appears that you are able to read, so you should have seen the explanation.

 

But if I had to explain planetary orbits to a female
I'm curious; since your other trolling seems to be successful, why add in sexism?

 

, I would sooner do so by pushing a pendulum so it swings in a circle, rather than have to screw a gramophone to a roundabout and then try to convince her that space contains comparable structures.
From this, I'm beginning to doubt that you even understand what epicycles are.

No, what I would say is that Feynman could not explain magnetism because he did not really understand it, but it is an interesting clip. I do admire Feynman, he understood a lot and did his best to share his understanding; unlike today’s celebrity physicists who understand little, and try to mysticise the universe.

Yay, another baseless attack on mainstream physicists.

 

Given physicists’ current understanding, it would seem reasonable to say that electrons repel each other and attract positrons, merely because it is in their nature to do this. But clearly magnetism is not a fundamental force. Lay 2 wires side by side, there is negligible force between them, pass currents in the same direction the wires attract, pass currents in opposite directions they repel. These forces are described as magnetic, therefore at least some magnetic forces must be caused by electric currents or the motion of electrons. It also inclines me to think that, contrary to popular belief, magnetic forces should really be described as like attracting like, and repelling unlike.
Is anybody interested in the cause of magnetism, or is that too mundane for modern physicists?

Your "explanation" is what is mundane here. You have a bunch of words that say little and show even less knowledge.

=Uncool-

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Magnetism is a good example of why physics should also be about why things happen, and not just be about what happens.

 

What is the explanation of why two wires next to each other with currents moving in the same direction, move towards each other?

 

How is this explained when electrons normally push each other apart?

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Epicycles might be simple for great minds like yourself and Bignose. But if I had to explain planetary orbits to a female, I would sooner do so by pushing a pendulum so it swings in a circle, rather than have to screw a gramophone to a roundabout and then try to convince her that space contains comparable structures.

 

!

Moderator Note

I fail to see why an explanation to a male would differ from one given to a female. Take care not to violate rule 1c

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I'm curious; since your other trolling seems to be successful, why add in sexism?

Actually my other attempts at trolling have not been successful, I have tried to provoke physics-believers into discussing and defending the details of their beliefs, but all I have had in response is vague generalisations and being told I am ignorant and heretical.

 

Magnetism is a good example of why physics should also be about why things happen, and not just be about what happens.

 

What is the explanation of why two wires next to each other with currents moving in the same direction, move towards each other?

 

How is this explained when electrons normally push each other apart?

 

In theory, if one of the wires was replaced by a hollow tube, and electrons were fired down the middle, then the electron paths would curve due to the wire’s magnetic field and collide with the side of the tube, forcing it towards or away from the wire depending on the direction of the currents. But that does not explain the equal and opposite force that the flying electrons exert on the wire.
In physics-speak, one could say that the force between two wires is the result of the Lorentz force on the moving electrons, but that does nothing what a magnetic field is or why an electric current creates a magnetic field.
Physicists appear to have mastered magnetic fields mathematically, and to use in technology, but figuring out what they really are may be beyond the capacity of the human brain.
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Actually my other attempts at trolling have not been successful, I have tried to provoke physics-believers into discussing and defending the details of their beliefs, but all I have had in response is vague generalisations and being told I am ignorant and heretical.

In my experience with you, newts, I cited original works (e.g. the paper in which the 1st experimental evidence for quarks was published) and you refused to read it. This goes both ways, buddy. Your refusal to actually do some work to learn about what current physics says really demonstrates that even if someone bothered to 'discuss and defend' what current physics is, it would just fall on deaf and uninterested ears, anyway.

 

In short, I call shenanigans on your expressed desire to learn about the mainstream. Because you sure haven't demonstrated it to date. I am always willing to give you the benefit of the doubt, but even this post doesn't seem to me to be a step in the right direction. If you are truly sincere in the above expression, your first step is to learn the current models and what they actually say -- not what some pop-sci metaphorical interpretation of it actually is.

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Actually my other attempts at trolling have not been successful, I have tried to provoke physics-believers into discussing and defending the details of their beliefs, but all I have had in response is vague generalisations and being told I am ignorant and heretical.

Bullshit. Both Bignose and I cited original papers and experiments, and offered to explain several things to you.

In theory, if one of the wires was replaced by a hollow tube, and electrons were fired down the middle, then the electron paths would curve due to the wire’s magnetic field and collide with the side of the tube, forcing it towards or away from the wire depending on the direction of the currents. But that does not explain the equal and opposite force that the flying electrons exert on the wire.

You seem to have forgotten the positively charged nuclei, which are a large part of the explanation here.

 

In physics-speak, one could say that the force between two wires is the result of the Lorentz force on the moving electrons, but that does nothing what a magnetic field is or why an electric current creates a magnetic field.
It does tell us "why" an electric current creates a magnetic field: that the magnetic field is just our name for the force that arises out of the movement of electrically charges objects.

 

Physicists appear to have mastered magnetic fields mathematically, and to use in technology, but figuring out what they really are may be beyond the capacity of the human brain.

What do you mean by "what they really are"? Now who is mysticizing?

 

So you agree that mainstream physicists have "mastered magnetic fields mathematically"? In other words, that they have managed to come up with models that are amazingly accurate?

=Uncool-

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Magnetism is a good example of why physics should also be about why things happen, and not just be about what happens.

 

What is the explanation of why two wires next to each other with currents moving in the same direction, move towards each other?

 

How is this explained when electrons normally push each other apart?

Well, for one thing, you seem to be forgetting about the positively charged nuclei in the wire - those also have an effect, and when there is no current, it's an equal and opposite effect to that of the electrons. That's why when there's no current, there's also no force.

 

Now, a wire here is assumed to lack charge relative to our original frame; this means that the linear density of the positive and negative charges (protons and electrons) is equal relative to this frame. In other words, relative to this frame, the wire looks like a line of stationary positive charges and another line of moving negative charges, such that the spacing between charges is the same for both of these. Relative to this frame, the electrical field from the entire wire is then 0.

 

One of the ideas of relativity is that distance and time are relative, although charge isn't. So let's take a look at what's happening from another frame - the frame where instead of the wire (which basically means the positively charged nuclei) being at rest, the electrons are at rest and the nuclei are moving. Relative to this frame, what is the linear charge density of both the nuclei and the electrons in the other wire? Here, we're going to look at the current going in the same direction.

 

Well, the electrons in the other wire were moving at the same speed as the electrons in this wire. If we do the relativistic calculations, we get that the distance between charges would therefore increase - so the linear charge density for the negative charges would decrease, and so the repulsive force between the negatively charged electrons would decrease. What about the force between the electrons and the nuclei? Well, the nuclei weren't moving, and now they are - so the distance between them has decreased - and so the force between the electrons and the nuclei in the other wire has increased. So if in total, there was no force originally, there now is an attractive force between the two wires. And we call that attractive force magnetism.

 

I could show you the math explicitly, if you want, but it would take me a bit longer to write up.

=Uncool-

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In my experience with you, newts, I cited original works

I did not mean to sound ungrateful, rather to try to get more focus on the physics. I like the fact that in your posts you frequently state that it is likely that some current theories are wrong; but I am not aware of you ever stating specifically which theories you consider wrong. I guess if you did, you would be in trouble with your colleagues; but if everybody is too afraid to be controversial, how can wrong theories ever be replaced?

 

Now, a wire here is assumed to lack charge relative to our original frame; this means that the linear density of the positive and negative charges (protons and electrons) is equal relative to this frame. In other words, relative to this frame ........................

 

Thanks for providing the physicists’ explanation. Obviously whoever came up with that theory knew the answer he wanted to achieve, but the problem is that it is too complex and illogical for me to test it. Presumably it predicts the correct Lorentz force on an electron moving parallel to the wire, but does it also predict the same numerical value for an electron moving directly towards and away from a wire?
The Lorentz force acts on an electron moving in a magnetic field; but if the electron is stationary and the magnet moves, then the force on the electron is traditionally explained by saying that a changing magnetic field creates an electric field. Clearly it is illogical to have two different explanations for the force resulting from the relative movement between an electron and a magnet. So it might seem logical to assume that magnetic and electric forces are somehow the same thing.
However if we start a current flowing in a superconducting ring, the ring now contains more energy; so in theory if it was put on a very accurate scale, it would register greater mass. The kinetic energy of the electrons flowing round the ring, contribute an insignificant quantity of the added mass. So most of the added mass must be contained in the magnetic field surrounding the ring.
Magnetic fields therefore exist in the same way that electric fields exist. A hydrogen atom is lighter than the combined mass of a proton and an electron, because the electric fields partially cancel out. Similarly two magnets locked together under magnetic force, must have lower mass than if they are separate. Magnetic and electric forces are both a disturbance or compression of the surrounding space, but they cannot be the same thing.
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newts, on 06 May 2013 - 20:51, said:

I did not mean to sound ungrateful, rather to try to get more focus on the physics. I like the fact that in your posts you frequently state that it is likely that some current theories are wrong; but I am not aware of you ever stating specifically which theories you consider wrong. I guess if you did, you would be in trouble with your colleagues; but if everybody is too afraid to be controversial, how can wrong theories ever be replaced?

Why must you presume to know who my colleagues even are? Why does that even matter in the least? How does this address any of the concerns brought up to you?
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Well, for one thing, you seem to be forgetting about the positively charged nuclei in the wire - those also have an effect, and when there is no current, it's an equal and opposite effect to that of the electrons. That's why when there's no current, there's also no force.

 

Now, a wire here is assumed to lack charge relative to our original frame; this means that the linear density of the positive and negative charges (protons and electrons) is equal relative to this frame. In other words, relative to this frame, the wire looks like a line of stationary positive charges and another line of moving negative charges, such that the spacing between charges is the same for both of these. Relative to this frame, the electrical field from the entire wire is then 0.

 

One of the ideas of relativity is that distance and time are relative, although charge isn't. So let's take a look at what's happening from another frame - the frame where instead of the wire (which basically means the positively charged nuclei) being at rest, the electrons are at rest and the nuclei are moving. Relative to this frame, what is the linear charge density of both the nuclei and the electrons in the other wire? Here, we're going to look at the current going in the same direction.

 

Well, the electrons in the other wire were moving at the same speed as the electrons in this wire. If we do the relativistic calculations, we get that the distance between charges would therefore increase - so the linear charge density for the negative charges would decrease, and so the repulsive force between the negatively charged electrons would decrease. What about the force between the electrons and the nuclei? Well, the nuclei weren't moving, and now they are - so the distance between them has decreased - and so the force between the electrons and the nuclei in the other wire has increased. So if in total, there was no force originally, there now is an attractive force between the two wires. And we call that attractive force magnetism.

 

I could show you the math explicitly, if you want, but it would take me a bit longer to write up.

=Uncool-

 

Thanks Uncool,

 

Is that the accepted explanation for magnetism - that it involves the positive charges from the nucleus as well as the electrons?

 

For example, if an electron is moving on its own in space, would it generate a magnetic field, or just a negative electric field?

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Thanks Uncool,

 

Is that the accepted explanation for magnetism - that it involves the positive charges from the nucleus as well as the electrons?

 

For example, if an electron is moving on its own in space, would it generate a magnetic field, or just a negative electric field?

It would generate a magnetic field. This is not "the accepted explanation for magnetism", but a demonstration of how "a current generates a magnetic field" falls directly out of "an electric field relative to one frame gains a magnetic component relative to another frame".

=Uncool-

 

I did not mean to sound ungrateful, rather to try to get more focus on the physics.

Again, bullshit. You don't ever focus on the physics. You still have yet to address the papers and the data - and as far as I can tell, you still have yet to even acknowledge them.

I like the fact that in your posts you frequently state that it is likely that some current theories are wrong; but I am not aware of you ever stating specifically which theories you consider wrong. I guess if you did, you would be in trouble with your colleagues; but if everybody is too afraid to be controversial, how can wrong theories ever be replaced?

How is this at all relevant to anything Bignose posted?

Thanks for providing the physicists’ explanation.

You're welcome, but this is one of the most common explanations in every book on basic electromagnetism in special relativity - the fact that you don't know it shows that you don't know even the basics of special relativity. So again, you are trying to dispute something that you don't know. In order to dispute a theory, you have to know what the theory says in the first place.

Obviously whoever came up with that theory knew the answer he wanted to achieve,

"Obviously"? Please explain.

but the problem is that it is too complex and illogical for me to test it.

"Complex"? Fine, but if you're going to refuse to understand it, you have no ground on which to dispute it. "Illogical"? Please explain. And finally, it's easy to test - if you want, I can write the actual numbers to show the magnetic field generated by a wire according to this explanation, and you can check that it's right.

Presumably it predicts the correct Lorentz force on an electron moving parallel to the wire, but does it also predict the same numerical value for an electron moving directly towards and away from a wire?

Do you want me to do the calculation?

 

The Lorentz force acts on an electron moving in a magnetic field; but if the electron is stationary and the magnet moves, then the force on the electron is traditionally explained by saying that a changing magnetic field creates an electric field. Clearly it is illogical to have two different explanations for the force resulting from the relative movement between an electron and a magnet. So it might seem logical to assume that magnetic and electric forces are somehow the same thing.
However if we start a current flowing in a superconducting ring, the ring now contains more energy; so in theory if it was put on a very accurate scale, it would register greater mass. The kinetic energy of the electrons flowing round the ring, contribute an insignificant quantity of the added mass. So most of the added mass must be contained in the magnetic field surrounding the ring.
Magnetic fields therefore exist in the same way that electric fields exist. A hydrogen atom is lighter than the combined mass of a proton and an electron, because the electric fields partially cancel out. Similarly two magnets locked together under magnetic force, must have lower mass than if they are separate. Magnetic and electric forces are both a disturbance or compression of the surrounding space, but they cannot be the same thing.

That sure is a bunch of statements and a conclusion, but none of the statements supports the conclusion in any way.

=Uncool-

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