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"Veritasium" (YT) - "The Big Misconception About Electricity" ?

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penfold:

--- Quote from: aetherist on March 03, 2022, 09:16:54 pm ---[...]
And i have used Excel to look into the behavior of my electons, compared to old (electron) electricity.
Plus as i said i used Excel to look into 3 electrons bumping 3 electrons to help find the speed of old (electron) electricity.
I made my own Excel programs for calculating say Coulomb force etc. But nowadays there are plenty of online calculators for almost everything.
[...]

--- End quote ---

Ahh yeah, when it comes down to the numbers of it, there's very little you can't do in excel, I guess it's only really quantum when that starts to get obscene, matrices as exponents... yuck. A 1D finite-difference Maxwell 'yee cell' does quite well in excel as well. Decimal places there is also quite interesting, after-all there aren't many instruments that can resolve to that precision directly and a numerical solution (in double precision at least) of something like time dilation, integrating a lot of small effects close to the rounding error (numerical noise floor) wouldn't make for a convincing proof from either side.
But, from a mainstream physics perspective, that's where the symbolic solutions (which can be more or less so apparent in different representations) and analysing the uncertainties that can arise due to noises, offsets and drifts (assumed from other experiments) and comparisons between repeat measurements are quite valuable. It's quite easy (for me at least) to forget quite how big 'physics' really is when considering that error analysis, statistics and computational techniques are pretty huge areas of study in themselves.

TimFox:
One of my engineer co-workers complained that Excel couldn't handle imaginary or complex numbers directly.
I reminded him that Excel was invented by accountants, and they were not allowed to use imaginary numbers under penalty of law.

adx:

--- Quote from: HuronKing on March 02, 2022, 04:51:22 pm ---
--- Quote from: adx on March 02, 2022, 03:30:21 pm ---
Some latch onto aethers, others to fields, as if they are real (some experimental evidence suggests that they are). Some go along with what the current fashionable consensus might be, others might be happy enough with the knowledge that something like the magnet force 'just is' and see no more mystery in it travelling through empty space than a particle going through an empty region. After all - there is no proof an object is not influenced only by its immediate surroundings (some evidence they are), there is no reason to suppose that anything in between the points is needed to mediate anything where there is no cause and effect there, and no proof that anything actually travels through the space.

So that gets back to the magnets. If I move one, we now know (or can justifiably assume to know) that the potential action appears to travel at the speed of light. This statement alone perfectly defines a spherical shell of potential action expanding at the speed of light. Forgetting about the mechanics of BxH for the moment, that qualitatively defines the wavefront travelling through space - hence what I said about "we are watching the fabric of time itself in action".


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Ok I think I accept Feynman's answer, that we can keep asking "why" ad nauseam after hearing "they do". But his appeal is not to something deep and mysterious, instead to something so shallow and readily apparent that it gets taken for granted.

I brought up my observation(s) in this same light - a simplistic view mixed with up to date knowledge. Yet without getting the details correct (or needing to, being the point) or cherry-picking anything beyond a speed, or even thinking, I have come up with a picture that looks the same as a full Maxwell simulation on screen (ie, animator vs field solver).

To that I ask "why"? Did I cherry-pick the only thing that matters? I'm talking (in my earlier post) about the H field and its momentum, the slowing.

On the other hand, I did find this yesterday, I don't know if connected to anyone here, but it seems like a good way to refresh (any)one's tattered or effectively nonexistent knowledge:

https://www.maxwells-equations.com/m/index.php

HuronKing:

--- Quote from: adx on March 04, 2022, 06:36:38 am ---Ok I think I accept Feynman's answer, that we can keep asking "why" ad nauseam after hearing "they do". But his appeal is not to something deep and mysterious, instead to something so shallow and readily apparent that it gets taken for granted.
--- End quote ---

I don't think that's quite what he is saying. He is saying that the underlying phenomena is so deep and mysterious that to truly understand it requires appealing to logic and analysis techniques that fall very far outside our ordinary, everyday intuition.

Even his quick answer around the 5:38 minute mark belies an analogy that is imperfect if he had been pressed on it - that about 'electrons spinning in iron and getting lined up to amplify the effect of the field so you can feel the force between two magnets at a large distance.'
The amount of mathematical rigor and physical experiment to arrive at that explanation for forces between magnets is enormous and requires a lot of preparatory study and this is why Feynman says he can't explain magnets in terms familiar to the untrained because the analogies you start to make end up sounding ridiculous (rubber bands, or noting that electrons have an anomalous magnetic dipole moment...)
"Magnets are magnetic because they're made up of lots of little magnets."  ;D
 
Some people might say he just sucks as a teacher... but I laugh at that.

And this is also the reason relativity and quantum mechanics are so often attacked by crackpots as the article I posted many pages ago goes into. The predictions of these theories are so far afield from our everyday experience that one could have a visceral reaction to accepting it... until one really dives into the experiments and mathematics that predict the phenomena (and having to ignore all the devices we use whose operation was engineered from the physics). Then, as Feynman says in his other video on pseudoscience I posted, you can't just tear down the extant theory without putting SOMETHING ELSE there to replace it that has the same predictive power as the extant theory. This is why GR superseded Newtonian Gravity, of course - GR predicts everything NG does while also being able to accurately predict the observed perihelion of Mercury.

It's also why I have some small contempt for people who say they want to overturn all of physics without even a passing understanding of multivariable vector calculus.


--- Quote ---I brought up my observation(s) in this same light - a simplistic view mixed with up to date knowledge. Yet without getting the details correct (or needing to, being the point) or cherry-picking anything beyond a speed, or even thinking, I have come up with a picture that looks the same as a full Maxwell simulation on screen (ie, animator vs field solver).

To that I ask "why"? Did I cherry-pick the only thing that matters? I'm talking (in my earlier post) about the H field and its momentum, the slowing.
--- End quote ---

You can make a picture that explains one aspect of the phenomena but the power of Maxwell's Eqs is that it is predictive of ALL (in the classical limit) electromagnetic phenomena.

I haven't followed the ancillary discussions closely enough to comment any more substantially than that.  :-X


aetherist:

--- Quote from: HuronKing on March 04, 2022, 06:58:14 pm ---And this is also the reason relativity and quantum mechanics are so often attacked by crackpots as the article I posted many pages ago goes into. The predictions of these theories are so far afield from our everyday experience that one could have a visceral reaction to accepting it... until one really dives into the experiments and mathematics that predict the phenomena (and having to ignore all the devices we use whose operation was engineered from the physics). Then, as Feynman says in his other video on pseudoscience I posted, you can't just tear down the extant theory without putting SOMETHING ELSE there to replace it that has the same predictive power as the extant theory. This is why GR superseded Newtonian Gravity, of course - GR predicts everything NG does while also being able to accurately predict the observed perihelion of Mercury.
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GTR does not predict Mercury's orbit. Firstly it was a postdiction, after a few years of trying (where Einstein finally got his recipe right). Secondly we are not sure what the size of the anomaly is. Thirdly we are not sure of the Newtonian component. Fourthly modern computer analysis shows that GTR duznt even give Mercury a proper orbit, Mercury flies off in a short time.

--- Quote from: HuronKing on March 04, 2022, 06:58:14 pm ---It's also why I have some small contempt for people who say they want to overturn all of physics without even a passing understanding of multivariable vector calculus.
--- End quote ---
Stephen Crothers explains that GTR invokes pseudo-vectors, & that Einstein lacks an understanding of vectors.

--- Quote from: HuronKing on March 04, 2022, 06:58:14 pm ---You can make a picture that explains one aspect of the phenomena but the power of Maxwell's Eqs is that it is predictive of ALL (in the classical limit) electromagnetic phenomena.
--- End quote ---
I thought that Einstein got the idea for his 1905 paper on STR because the standard explanation failed as to why if a magnet was passed through a loop of wire then the wire got an electric current & vice versa.
However Einsteinists are happy to ignore that Einstein's STR fails to explain Faraday's homopolar disc generator, re the voltage produced by spinning discs & spinning magnets. More than that, STR contradicts those experiments. In other words the experiments prove that STR is wrong, at least re that aspect of electricity.
Faraday's homopolar disc generator is however easily explained by the existence of the aether.

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