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Copernicus
2015-Aug-30, 10:35 PM
New theory leads to radiationless revolution

http://www.anu.edu.au/news/all-news/new-theory-to-lead-to-radiationless-revolution

The author states the toroid structure could produce a radiationless structure. Could dark matter be constructed in such a way? Or are there other reasons we should be seeing dark matter besides radiation or gravity?

Bergman has been saying for years that this shape can account for the magnetic moment of the electron. Although he doesn't find a way for the electron to look like a point particle to us.

http://www.commonsensescience.org/pdf/articles/spinning_charged_ring_model_of_electron_yields_new .pdf

John Mendenhall
2015-Aug-31, 04:15 AM
The second link doesn't work.

The first link to Australlian National University works. Help us poor uninformed North Americans, maties. I never heard of ANU before.

Jeff Root
2015-Aug-31, 07:03 AM
Both links worked for me.

Pretty interesting, for something so mathematical.

-- Jeff, in Minneapolis

Shaula
2015-Aug-31, 09:24 AM
Re: The second paper. The magnitude of the intrinsic angular momentum of the electron is \frac{\sqrt{3}\hbar}{2}, not \frac{\hbar}{2}, which is just one component of it. Which makes most of the numbers they get out wrong.

Swift
2015-Aug-31, 12:25 PM
http://www.commonsensescience.org/pdf/articles/spinning_charged_ring_model_of_electron_yields_new .pdf
The parent website, commonsensescience.org has this:

Common Sense Science is a body of theory regarding matter and forces that describes the physical world using geometric models, absolute time and Galilean space in a way that strives to be consistent with experimental observations and free of internal contradictions.
This is someone's ATM website.

John Mendenhall
2015-Aug-31, 02:03 PM
The parent website, commonsensescience.org has this:

This is someone's ATM website.

Oh yeah. 10 years at UT and you can smell ATM from a mile away.

Jeff Root
2015-Aug-31, 10:41 PM
The magnitude of the intrinsic angular momentum of the
electron is \frac{\sqrt{3}\hbar}{2}, not \frac{\hbar}{2}, which is just one component of it.
What are the components and why the square root of 3 ?

-- Jeff, in Minneapolis

John Mendenhall
2015-Sep-01, 12:54 AM
What are the components and why the square root of 3 ?

-- Jeff, in Minneapolis

Here, Jeff:

http://ocw.mit.edu/courses/chemistry/5-61-physical-chemistry-fall-2007/lecture-notes/lecture23.pdf

ShinAce
2015-Sep-01, 04:07 AM
I did some digging.

The original Nature article is here:
http://www.nature.com/ncomms/2015/150827/ncomms9069/full/ncomms9069.html

The paper seems legit and says that there are two ways to calculate how much light something will bounce. Sometimes these methods don't agree. In the case of a silicon disk of a certain size, if you measure(from afar) the light that bounces off, you find it matches with one method of calculating that experiment. The other method needs to be patched to account for something called an anapole moment. This anapole moment is what was seen. The disk still 'radiates' in the near field, and only succeeds at suppressing reflection for one specific color.

I'm not even going to touch that Bergman paper. It's not worth my time.

ShinAce
2015-Sep-01, 04:16 AM
Jeff:
The components are x, y, and z. The spin in the x direction is hbar/2. The spin in the y direction is hbar/2...

Since spin is a vector, the components add as vectors. The total is given by the Pythagorean theorem(hypotenuse of a 3D triangle) where each side of the triangle is one of the components.

Let's call the total angular momentum w. Each component, x,y,z is equal to hbar/2.

But w2 = x2 + y2 + z2

So w = squareroot(3) * hbar/2

ShinAce
2015-Sep-01, 04:21 AM
It's common in physics to define one axis and only care about that one axis. But that's a 1D problem designed to simplify the math and get to the juicy bit.

It is assumed that when you move to 3D, you do your geometry in 3D as well.

Jeff Root
2015-Sep-01, 08:00 AM
The components are x, y, and z. The spin in the x direction
is hbar/2. The spin in the y direction is hbar/2...
I need to ask: All you left off after the ellipsis is
"The spin in the z direction is hbar/2." Correct?

If so, that makes no sense to me. If the spin in the
x direction is hbar/2, then I would expect the spin in
the y and z directions to each be zero.

I am not going to understand the brief PDF file that
John Mendenhall linked, but I'll ask about it anyway.

Beside the diagram for Spin Angular Momentum is a
notation which I'll spell out as S(sub z) = hbar/2. There
appears to be a very short callout line connecting this
notation to the vertical line representing the z axis.
I surmise that they could have done likewise for the x
and y axes: S(sub x) = hbar/2 and S(sub y) = hbar/2.
Is that correct?

I also surmise that in both this diagram and in ShinAce's
reply (post #10, which this is a reply to) the x, y, and z
axes are completely arbitrary. The spin axis is not given
to be aligned with any particular axis, nor does it have
any particular alignment at all, but is instead imagined
to be a variable which could be measured relative to the
x, y, and z axes. Is that correct? If so, you probably
have a different, more standard way of expressing it.



Since spin is a vector, the components add as vectors.
The total is given by the Pythagorean theorem
(hypotenuse of a 3D triangle) where each side of the
triangle is one of the components.

Let's call the total angular momentum w. Each component,
x,y,z is equal to hbar/2.

But w2 = x2 + y2 + z2

So w = squareroot(3) * hbar/2
I would naively expect each component to have a different
value, such that if the value on say, the y axis happens to
be hbar/2, then the values on the other two axes must be
zero. What am I imagining incorrectly? Why do all three
components each have a value of hbar/2 ?

-- Jeff, in Minneapolis

Shaula
2015-Sep-01, 09:03 AM
It is worth noting that the three axial components of spin are non-commutating. You cannot know all three values at once. So while Shinace's reply appears to get the right result it is not for the right reasons. When you do the maths you find that overall spin is related to spin quantum number by the relationship given on this page (https://en.wikipedia.org/wiki/Spin_quantum_number).

Take a spin 3/2 particle as an example. If you assume each axis has spin 3/2 (leaving out units of h-bar) you get a total spin of sqrt(27) / 2, which is wrong. Using the equation above you get sqrt(15) / 2.

ShinAce
2015-Sep-01, 07:00 PM
My plan was to avoid a mess of mathematics to show that the total spin of the electron is not hbar/2. I don't see how I can show it with commutation relations without what would look like a big arbitrary mess of math.

The way I learned to solve the angular momentum of an electron in a hydrogen atom is by solving the Schrodinger equation. However, I cannot reasonably expect someone on the forum to be able to follow that procedure. It can be found here: http://users.physik.fu-berlin.de/~pascual/Vorlesung/SS06/Slides/AMOL-L1d.pdf

You start with the Schrodinger equation, which is a partial differential equation. You then use the method of separation of variables. You then find the general solution.

The general solution to the 'angular' part indicates that angular momentum goes as L(L+1). Here I've used capital L because lower case l looks like 1. It's only when L is a large number that we can simplify the expression to L^2 and then take the squareroot to get an expression for L.

It's too complicated to go over completely for the sake of debunking a junk paper.

However, my main point is that if you assume the angular momentum of an electron is hbar/2, then you are working in 1D.

For a free electron, you only have spin. So the total angular momentum of the electron would be |s| = +/- hbar * squareroot(s(s+1)) = hbar * squareroot(3/4) = ...

Where s = 1/2 and |s| is the magnitude of the total spin vector.

WayneFrancis
2015-Sep-02, 01:46 AM
Just a side note. ShinAce do you not use Latex?

Copernicus
2015-Sep-02, 02:18 AM
My plan was to avoid a mess of mathematics to show that the total spin of the electron is not hbar/2. I don't see how I can show it with commutation relations without what would look like a big arbitrary mess of math.

The way I learned to solve the angular momentum of an electron in a hydrogen atom is by solving the Schrodinger equation. However, I cannot reasonably expect someone on the forum to be able to follow that procedure. It can be found here: http://users.physik.fu-berlin.de/~pascual/Vorlesung/SS06/Slides/AMOL-L1d.pdf

You start with the Schrodinger equation, which is a partial differential equation. You then use the method of separation of variables. You then find the general solution.

The general solution to the 'angular' part indicates that angular momentum goes as L(L+1). Here I've used capital L because lower case l looks like 1. It's only when L is a large number that we can simplify the expression to L^2 and then take the squareroot to get an expression for L.

It's too complicated to go over completely for the sake of debunking a junk paper.

However, my main point is that if you assume the angular momentum of an electron is hbar/2, then you are working in 1D.

For a free electron, you only have spin. So the total angular momentum of the electron would be |s| = +/- hbar * squareroot(s(s+1)) = hbar * squareroot(3/4) = ...

Where s = 1/2 and |s| is the magnitude of the total spin vector.

Does Bergman's theory make any sense if their are three toroids?

ShinAce
2015-Sep-02, 02:55 AM
I would just like to point out that you originally connected two papers. By simply analyzing the first paper, we can see that it's not usable for the second paper. Personally, that's where I stopped. What if we modify the premise of the second paper? I have no idea, because the first paper was already a deal breaker.

And no, I don't use latex, but I do know of its existence.

Shaula
2015-Sep-02, 05:08 AM
Does Bergman's theory make any sense if their are three toroids?
Probably not, because the mass he works out is dependent on the square of the charge while the stability forces are dependent on just the charge. Start splitting the charge between multiple toroids and the numbers he gets are probably going to be wrong.

I say probably because I have not crunched the numbers to see. Nor am I going to. I suspect the idea has bigger issues to do with relativistic effects anyway.

trinitree88
2015-Sep-07, 01:19 AM
Probably not, because the mass he works out is dependent on the square of the charge while the stability forces are dependent on just the charge. Start splitting the charge between multiple toroids and the numbers he gets are probably going to be wrong.

I say probably because I have not crunched the numbers to see. Nor am I going to. I suspect the idea has bigger issues to do with relativistic effects anyway.

And the mass needs to be dependent on the energy/ c sqrd to be consistent with SR...

BigDon
2015-Sep-16, 08:26 PM
I did some digging.

The original Nature article is here:
http://www.nature.com/ncomms/2015/150827/ncomms9069/full/ncomms9069.html

The paper seems legit and says that there are two ways to calculate how much light something will bounce. Sometimes these methods don't agree. In the case of a silicon disk of a certain size, if you measure(from afar) the light that bounces off, you find it matches with one method of calculating that experiment. The other method needs to be patched to account for something called an anapole moment. This anapole moment is what was seen. The disk still 'radiates' in the near field, and only succeeds at suppressing reflection for one specific color.

I'm not even going to touch that Bergman paper. It's not worth my time.

Bold mine.

I apologize for interjecting here but ShinAce's comment got me to thinking about that piece of granite furnishing I saw while moving a very wealthy man's home that was a deep blood red until you backed away from it about six feet or so. Then the table appeared to be completely black. (Somehow shiny without a central highlight.)

It wasn't toroidal in the least.

ShinAce
2015-Sep-17, 09:11 PM
Like when you make large soap bubbles. They start off with vibrant colors only to lose their color before they burst.

Likewise, a the CDs used in the Playstation 1 were often black. Yet these disks could still give the diffraction colors you see when looking at a CD at different angles.

Interference is a wonderful effect. You can even get 'chameleon' paint jobs for your car, obtained by adding pieces of crushed up pearl to get diffration. Far away, the car appears a solid color. As it drives by a few feet away, a semi-rainbow of color is seen to wash over the car.

Copernicus
2015-Sep-27, 02:07 AM
I wanted to mention the Bergman site only because he had suggested a long time ago that the toroid shape along with with the magnetic and electric interaction would keep the shape stable without radiating any energy away.

http://www.commonsensescience.org/pdf/articles/spinning_charged_ring_model_of_electron_yields_new .pdf

Equation 24

Although he may not be right, about some of the theory, I would not doubt that toroids are the shape of some parts of the electron, proton, neutron, muon etc. that we experience.

Shaula
2015-Sep-27, 06:04 AM
Although he may not be right, about some of the theory, I would not doubt that toroids are the shape of some parts of the electron, proton, neutron, muon etc. that we experience.
"His predictions may be wrong but I have no doubt he is actually right"

Not sure why you reposted that link - it has already been shown that his model doesn't yield predictions in accordance with observations. The whole point of this idea was that you could reproduce observations using fairly simple classical concepts. Except, as shown above, he cannot. The system that has been constructed is highly sensitive to angular momentum so the required change will break it badly.

Jeff Root
2015-Sep-27, 07:04 AM
Shaula,

I didn't argue about it because I can't, but I was not
convinced that what you said in post #4 was correct.
It seems far more likely -- in my state of ignorance --
that you simply misunderstood how the value in the
paper was being used, than that it was being used
incorrectly. I was able to more-or-less follow the
mathematical arguement in the paper fairly well, and
it seems implausible that the author could have made
such an obvious mistake in such a fundamental part
of his reasoning so early on. Without further evidence,
or an incredible amout of study on my part, I have to
presume that you made the mistake, not him.

-- Jeff, in Minneapolis

Shaula
2015-Sep-27, 07:47 AM
Shaula,
I didn't argue about it because I can't, but I was not convinced that what you said in post #4 was correct. It seems far more likely -- in my state of ignorance --that you simply misunderstood how the value in the paper was being used, than that it was being used incorrectly. I was able to more-or-less follow the mathematical arguement in the paper fairly well, and it seems implausible that the author could have made
such an obvious mistake in such a fundamental part of his reasoning so early on. Without further evidence, or an incredible amout of study on my part, I have to presume that you made the mistake, not him.
-- Jeff, in Minneapolis
So how am I supposed to argue this point with you? It boils down to "I liked that paper and because I liked that paper I am going to assume any criticism of it is wrong because I like that paper". If the quality of my arguments against one of your comments was "I don't understand what you are saying or the topic but I don't believe that a scientist capable of writing a well written paper can possibly be wrong" I'd be rightly pilloried.

In his model he had a toroid spinning around its central axis as fast as it could. There were no extra components of motion (because if there were it would ruin the symmetry he used to eliminate radiative losses). This toroid was fixed to have an angular momentum of hbar/2 and all the results for radius and so on stemmed from that. Of course this is from memory as that website won't load at the moment for me, but feel free to provide references and so on to show that I am wrong.

Copernicus
2015-Sep-27, 11:15 AM
So the dark matter article of a radiationless structure proposed a toroid shape for this. Bergman had the insight to suggest this shape for a radiationless structure. Was Bergman not the first to propose this idea? I don't know. That is my correlation to the two articles. Unless I am wrong, just about every scientist has said wrong stuff. That is not the point of my comparison. Skip all the stuff about Galilean physics etc. Please!

Shaula
2015-Sep-27, 01:29 PM
So the dark matter article of a radiationless structure proposed a toroid shape for this. Bergman had the insight to suggest this shape for a radiationless structure. Was Bergman not the first to propose this idea? I don't know. That is my correlation to the two articles. Unless I am wrong, just about every scientist has said wrong stuff. That is not the point of my comparison. Skip all the stuff about Galilean physics etc. Please!
Bergman wasn't even close to being the first to talk about anapole moments and structures. See the work of Ehrefest in 1910, Zeldovitch in the 50s, Devany Kim and Wolf in the 70s/80s ... And many more. https://en.wikipedia.org/wiki/Nonradiation_condition has some of the history of why it was important to find non-radiating configurations before QM came along.

Fuller papers on this topics:
http://www.nature.com/ncomms/2015/150827/ncomms9069/pdf/ncomms9069.pdf - the Nature communication about the Australian work you referenced.
http://arxiv.org/pdf/1211.0503v3.pdf - discussion of detection limits for Dark matter that can interact via an anapole moment.

Copernicus
2015-Sep-27, 02:36 PM
Bergman wasn't even close to being the first to talk about anapole moments and structures. See the work of Ehrefest in 1910, Zeldovitch in the 50s, Devany Kim and Wolf in the 70s/80s ... And many more. https://en.wikipedia.org/wiki/Nonradiation_condition has some of the history of why it was important to find non-radiating configurations before QM came along.

Fuller papers on this topics:
http://www.nature.com/ncomms/2015/150827/ncomms9069/pdf/ncomms9069.pdf - the Nature communication about the Australian work you referenced.
http://arxiv.org/pdf/1211.0503v3.pdf - discussion of detection limits for Dark matter that can interact via an anapole moment.

Thanks,

This is very useful.

Jeff Root
2015-Sep-27, 08:06 PM
So how am I supposed to argue this point with you?
It boils down to "I liked that paper and because I liked
that paper I am going to assume any criticism of it is
wrong because I like that paper".
Really? Is that what it boils down to? Can you prove
that that is what it boils down to? Because it sounds
very different from what I meant. And from what I
said.

You pointed out what you think is an error very near
the beginning of the paper. If it is an error, it is a very
basic and very obvious one, that would be quite difficult
to make in the first place, and very difficult to be missed
by other physicists before you. I have no reason to
think he made an error there except for your say-so.
What he said about the spin angular momentum of the
electron matches what I previously understood about it.
What you said does not. But I do not have the depth of
understanding required to argue the point.

It seems far more likely that you misunderstood what
he was saying than that he made the specific error you
claim he made.



In his model he had a toroid spinning around its central
axis as fast as it could. There were no extra components
of motion (because if there were it would ruin the symmetry
he used to eliminate radiative losses). This toroid was fixed
to have an angular momentum of hbar/2 and all the results
for radius and so on stemmed from that. Of course this is
from memory as that website won't load at the moment for
me, but feel free to provide references and so on to show
that I am wrong.
That jibes exactly with my memory of what he said. The
question is whether his use of hbar/2 was correct for his
purpose, or the (to me, very strange and surprising) value
you suggested is the correct one for his purpose.

-- Jeff, in Minneapolis

Shaula
2015-Sep-27, 08:38 PM
If it is an error, it is a very basic and very obvious one, that would be quite difficult to make in the first place, and very difficult to be missed by other physicists before you.
Which might just explain why this was 'published' by a website which rejects QM and GR in favour of 'common sense science' and I cannot find another copy of it to reread...


I have no reason to think he made an error there except for your say-so. What he said about the spin angular momentum of the electron matches what I previously understood about it. What you said does not. But I do not have the depth of understanding required to argue the point.
http://hyperphysics.phy-astr.gsu.edu/hbase/spin.html#c3
http://ocw.mit.edu/courses/chemistry/5-61-physical-chemistry-fall-2007/lecture-notes/lecture23.pdf

hbar/2 is the z component, the total spin angular momentum is sqrt(3).hbar/2. He used hbar/2 to get his results and required that there be no other components to maintain symmetry and to avoid unfortunate issues with lightspeed. So his results were wrong. As I said, show me I am wrong and I will accept your argument. I read the paper once - if I misunderstood then show me where I did.

ShinAce
2015-Sep-27, 09:48 PM
Which might just explain why this was 'published' by a website which rejects QM and GR in favour of 'common sense science' and I cannot find another copy of it to reread...
*snip*
As I said, show me I am wrong and I will accept your argument.


Awwww.... you beat me to it! It makes sense to me that a physicist wouldn't have corrected it because.... drumroll.... a physicist wouldn't have found it in the first place.

But Shaula, that would imply a situation like you and I encountered in posts #10, 13, and 14. One where a person is called our and held accountable for incorrect information. And once that type of situation reaches a common understanding, the argument suddenly ceases. You don't actually want to do science that way, do you?

Jeff Root
2015-Sep-27, 10:00 PM
hbar/2 is the z component, the total spin angular
momentum is sqrt(3).hbar/2.
Given that hbar/2 is the z component, then I expect
the x and y components to both be zero, so the total
spin angular momentum is hbar/2.

If the z component has some value less than hbar/2,
then I would expect the x and/or y values to be positive.

If you are saying that the observed component of spin
is always hbar/2, and the other components are never
observable, but are inferred, then I would expect that
the value in the paper refers to the observed component,
not the inferred total.

-- Jeff, in Minneapolis

ShinAce
2015-Sep-27, 10:15 PM
1) Given that hbar/2 is the z component, then I expect
the x and y components to both be zero, so the total
spin angular momentum is hbar/2.

2) If the z component has some value less than hbar/2,
then I would expect the x and/or y values to be positive.

3) If you are saying that the observed component of spin
is always hbar/2, and the other components are never
observable, but are inferred, then I would expect that
the value in the paper refers to the observed component,
not the inferred total.

-- Jeff, in Minneapolis

1) Why would you expect something you haven't even measured yet to be zero?

2) When was the last time you saw a spin value that was less than hbar/2 but greater than zero?

3) When did Shaula say the others components are never observable? We can prepare electrons and send them through a Stern-Gerlach setup. We prepare all electrons the same way. We now measure the z component of spin. Then we rotate the detector and measure the y component. You can't measure both at the same time, because detecting the particle 'destroys' it from further use. You can measure z today, y tomorrow, and x next Tuesday. Every single one of them will yield that the angular momentum (actually, the magnetic moment) is never 0.

Jeff Root
2015-Sep-28, 12:19 AM
1) Given that hbar/2 is the z component, then I expect
the x and y components to both be zero, so the total
spin angular momentum is hbar/2.

2) If the z component has some value less than hbar/2,
then I would expect the x and/or y values to be positive.

3) If you are saying that the observed component of spin
is always hbar/2, and the other components are never
observable, but are inferred, then I would expect that
the value in the paper refers to the observed component,
not the inferred total.
1) Why would you expect something you haven't even
measured yet to be zero?
Because I'm told that the spin of the electron is hbar/2,
and Shaula tells me that the spin of the z component of
the electron he is looking at is hbar/2, so I deduce that
the values of the x and y components must be zero.



2) When was the last time you saw a spin value that
was less than hbar/2 but greater than zero?
Never. I would be quite surprised if I did.



3) When did Shaula say the others components are
never observable?
He didn't. He said, as you say below, that all the
components cannot be observed at the same time.
So if the z component is observed to have a value of
hbar/2, I infer that the other two components cannot
be observed. If the z component were observed to
have a value greater than zero but less than hbar/2,
then I would infer that the other two components
have a net positive value which can be observed.



We can prepare electrons and send them through a
Stern-Gerlach setup. We prepare all electrons the
same way. We now measure the z component of spin.
Then we rotate the detector and measure the y
component. You can't measure both at the same time,
because detecting the particle 'destroys' it from further
use. You can measure z today, y tomorrow, and x next
Tuesday. Every single one of them will yield that the
angular momentum (actually, the magnetic moment)
is never 0.
Will every single one of those measurements yield that
the spin is hbar/2?

And what do you get when you measure on an axis that
is in-between the x, y, and z axes? You still get hbar/2,
don't you? Nomatter what the angle of the detector,
the spin is always measured to be hbar/2, isn't it?

That's the value the guy who wrote paper used.

-- Jeff, in Minneapolis

.

Shaula
2015-Sep-28, 05:45 AM
Because I'm told that the spin of the electron is hbar/2, and Shaula tells me that the spin of the z component of the electron he is looking at is hbar/2, so I deduce that the values of the x and y components must be zero.
Meaning you have just broken the commutation relationships - because now you know the value of the other spins precisely.

I quit on this one. Clearly you have decided, again, that it is time to dig your heels in and reject modern physics in favour of your own inferences. From past experience there is no point arguing.

Jeff Root
2015-Sep-28, 08:45 AM
Shaula,

Please, at the very least, explain these two things: First,
was I right that the spin is always measured to be hbar/2?
As far as I can tell, it is, but if I'm wrong about that, then
nothing else matters.

Second,

If I know the spin on the z axis, and therefore cannot know
the spins on each of the other two axes, can I know the sum
of the spins on the other axes? That is what I claimed.

If I can't know the sum of the spins on the other two axes,
then I can't ever know the total spin -- only the spin on a
single axis that I measure.

-- Jeff, in Minneapolis

ShinAce
2015-Sep-28, 07:57 PM
Here's what I went through in my intro to quantum mechanics course:
http://quantummechanics.ucsd.edu/ph130a/130_notes/node214.html

The answer is yes. It is possible to measure both the total(3D) size of the angular momentum AND one of the individual axes(z, in this case). But if you try to measure x and y, then your knowledge of the z component is necessarily uncertain.

Philosophical arguments are not needed, we have the experimental evidence. The best thing to do is just calculate the commutation relation.

However, I stand by my comment in post #14:
"My plan was to avoid a mess of mathematics to show that the total spin of the electron is not hbar/2. I don't see how I can show it with commutation relations without what would look like a big arbitrary mess of math."

I can't help you because it would require you to know the mathematics of commutation relations. But if you knew that math, and had an interest in physics, you could just read the link I posted and be done. I am confident that this will not happen. I am confident that you will appeal to common sense to understand something that defies common sense. You're stuck in a catch 22. If you admit you don't understand, then you have no argument. If you say you understand, then you don't.