[Bored chemist]

https://amtil.com.au/eb-fusion-specialists-in-electron-beam-welding/
Again, the electron beam travels straight through an unsymmetrical environment.

[Bored chemist]

There's a picture here of a man looking into an EB welding system.
https://joiningtech.com/jtforms/10_advantages_eb_welding/
You are trying to pretend that it is symmetrical.
It isn't.

[Mitko Gorgiev (OP)]

You should keep quiet.

No, you should keep quiet. You are on this forum more than ten years and you haven't started a single topic yet (only two insignificant). You have nothing to say, pal. You are only screaming around and insulting the people.
As I said, let us bet. I can bring a few thousand euros in the bet. If you are so sure that you know something, than accept the challenge. If you don't want my money, then you can give it to a charity organisation.

[Bored chemist]

You should keep quiet.

No, you should keep quiet. You are on this forum more than ten years and you haven't started a single topic yet (only two insignificant). You have nothing to say, pal. You are only screaming around and insulting the people.
As I said, let us bet. I can bring a few thousand euros in the bet. If you are so sure that you know something, than accept the challenge. If you don't want my money, then you can give it to a charity organisation.

It's true that keeping up with correcting nonsense posted by others takes up so much of my time that I seldom start threads.
You aren't helping.
Please explain how you still think that a symmetrical environment is important to a straight line trajectory for electrons in spite of the evidence that in (among other things) electron beam welding, they travel in straight lines  even in very unsymmetrical circumstances?

Also, please explain how "nothing" pushes electrons around.

[evan_au]

a strong cylindrical magnet with its positive pole down

Editorial: In English, we refer to the poles of a magnet as "North" and "South", not "+" and "-" (I can't comment on other languages).

This convention originated from the use of magnets in a compass, where the "North" pole of a compass pointed to the North (magnetic) pole of the Earth.

This can be confusing, because we know that opposite poles attract - in fact, the equivalent magnet inside the Earth has it's "South" pole at Earth's North pole(!).

one of the basic principles of nature is that the movement is always from the positive to the negative and not contrariwise

I would agree if you were talking of movement of:
- Heat from a higher temperature to a lower temperature
- Air from a higher pressure to a lower pressure
- (Conventional) current from a higher voltage to a lower voltage

However, as shown by comments in the thread you linked, Benjamin Franklin didn't know about electrons, so (around 1750) he defined the convention of "Positive" and "Negative", based on the relative electrical characteristics of silk and glass.
- This defines the direction of "Conventional" current from positive to negative. And in fact, in some semiconductors, charge really is carried in that direction.
- However, since the 1850s (a century after Franklin's work) we have known about electrons, and we know that in a copper wire, or a vacuum tube, they flow from negative to positive.

This can be confusing, because the electrons flow in the opposite direction from the "Conventional" current still taught in schools.

See: https://en.wikipedia.org/wiki/Benjamin_Franklin#Electricity
https://en.wikipedia.org/wiki/Electron#Discovery_of_free_electrons_outside_matter

let us examine it in front of the screen of a CRT television, monitor, or oscilloscope - we will always find that the detector shows intense positive electricity.

I agree that (in the past) when I passed my arm near a CRT tube, the hairs on my arm would move, so I agree that there is some electrostatic potential here, relative to my (probably) grounded body.

You always have to measure electricity relative to something.
- What is your reference point here? The Anode, the Cathode, or something else? This will determine whether it is "positive electricity" or "negative electricity". (Editorial: in English we say "positive charge" or "negative charge" for electrostatics.)
- Most devices that measure voltage have an internal "leakage current", which quickly dissipates an electrostatic charge. How did you measure whether the charge on the front of the screen was positive or negative?

One photo above shows a blue beam traveling through a tube, and hitting the end of a plain glass tube.
- This will not work for a CRT television or oscilloscope, because the beam will quickly charge up the inside of the glass, which will distort the path of the beam, and distort the image. (Plus, the tube must be a good vacuum, unlike the gas producing the blue glow.)
- So real CRTs have an electrode on the inside of the glass which collects the electrons striking the screen, and carries them away so that they don't build up and distort the image.
- To carry these electrons away quickly, this electrode must be at a positive potential relative to the cathode.

[Mitko Gorgiev (OP)]

a strong cylindrical magnet with its positive pole down

Editorial: In English, we refer to the poles of a magnet as "North" and "South", not "+" and "-" (I can't comment on other languages).
.....

In all languages the poles of a magnet are referred to as North and South. But "North" and "South" have no meaning for a magnet. They are only words for the geographic directions. The words "Plus" and "Minus" are far more natural for the magnetic poles. The Plus pole is the one which points North in the compass. It cannot be arbitrary, it cannot be a matter of human's convention. It is like to say, who a male and who a female is, were a matter of convention. There is something intrinsic in the bodies which determines the pole.

Please see this image from Wikipedia:

Wikipedia article electric_charge.png (17.55 kB . 430x200 - viewed 5995 times)
Could we change the "convention" and reverse the arrows of the Plus and of the Minus. No, we can not. It will be unnatural. And exactly these properties have the Plus and the Minus in electricity and in magnetism. The Plus is an effect towards outside, the Minus is an effect towards inside. That can be seen with a naked eye. Please see "What is electromagnetic induction?" (Part 1 and 2). https://www.thenakedscientists.com/forum/index.php?topic=78632.0
or this shorter topic "Is the designation "positive" and "negative" in electricity arbitrary?" https://www.thenakedscientists.com/forum/index.php?topic=78171.0

I don't believe in the theory that material particles, called electrons, move through the metal wires. For me the electric current is immaterial electric and magnetic wind through the conductive path. (see "A new explanation of the electric current" https://www.thenakedscientists.com/forum/index.php?topic=78153.0)

What is an electric wind?
If we rub a piece of glass with a silk or woolen cloth, then the glass is positively electrified. We say that there is an electric field around the electrified glass. What is an electric field? Is it something material? Certainly not.
If the glass is not moving, then the field is also motionless. If the glass is moving, then the field is moving together with the glass. This moving field is an electric wind. This wind, of course, is immaterial, too. If we move the glass longitudinally to and fro a metal wire, then this wind propagates through the wire in a swirling motion to the other end.
The scientists of the first half of the 19th century spoke of the electric current through a wire as an electric field through it. And it was the right view.
Does anybody speak of the electromagnetic waves (let's say radio-waves) as of moving particles through the air? No, nobody. Just as the EM-waves are something immaterial, so it is the electric current through the metal wires.

There are many experimental evidence that the direction of the conventional current is the true direction of the current. The only "evidence" for the contrary direction is the CRT. But it is not an evidence, because what happens in a CRT is misinterpreted. There is no flow of negative electrons in the CRT, but it is an immaterial electromagnetic vortex.

Concerning Benjamin Franklin, please read this:
https://www.thenakedscientists.com/forum/index.php?topic=78171.msg589265#msg589265

Concerning how I have determined the polarity of the electricity in front of the CRT, please read my thread "What is electromagnetic induction? (Part 1)" https://www.thenakedscientists.com/forum/index.php?topic=78632.0

Here I want to clarify something which is not strictly connected to my OP, but since you have said that the voltage must be measured relative to something, I have to say this:
It is not quite true that for measuring the voltage there must be two points. Actually it depends on how we would define the term "measuring".
Let's say we have two containers like this below, but the water jets from the two are not equal. We say that the pressure in one of them is higher than the pressure in the other. Similarly, if we touch with an ordinary phase-tester (PT) (one-contact neon test light) two different wires and notice that the lamp of the PT lights up stronger with the first wire than with the second, then we can say that the voltage in the first wire is greater than the voltage in the second. This is also measuring.

WATER JET.JPG (7.08 kB . 460x350 - viewed 6057 times)

But if someone asks you how much greater the voltage in the first wire is than in the second (1.5 times or 2 times or 3.7 times etc.), then you cannot answer the question without measuring those voltages relative to a second point which will be called a reference point.

In the above mentioned thread about the electromagnetic induction there are two circuits with two transistors each. When I move the wire of the so-called (+)circuit to and fro a CRT screen, then the lamp lights up only during the movement towards the screen. When I do the same with the so-called (‒)circuit, then the lamp lights up only during the movement away from the screen. The lamp lights up pretty strong even by slow movements. These experiments indicate that the electricity is positive and intense.

Concerning the CRT with the blue beam: the image is from this YouTube video:

It is a school CRT (more precisely Braun tube) just as any CRT in a CRT TV, monitor or oscilloscope. It is true that there is carbon layer on the side wall of the commercial TV, monitor and oscilloscope tubes, which is connected to a positive voltage to better focus the beam. If you believe that the positive electricity comes from this carbon layer, then let's determine the electricity's polarity in front of a screen of a tube which doesn't have this carbon layer. I claim that it will be also positive. I am ready to bet on this.
There is a small amount of an inert gas inside that tube to make the beam (actually the vortex) visible. The blue color comes from it. The vacuum in that tube is also high. The inert gas has no influence on the phenomena, except for making the vortex visible.

My prediction that a non-symmetrical conical tube (mentioned in my OP) would make the beam curved even without an external electric or magnetic field could clear all doubts. I don't have the means to experiment, otherwise I would have carried out this experiment so far.

[Mitko Gorgiev (OP)]

a strong cylindrical magnet with its positive pole down

Editorial: In English, we refer to the poles of a magnet as "North" and "South", not "+" and "-" (I can't comment on other languages).

Just for little fun to break the very serious discussion.

A bit strange thought crossed my mind when I was thinking about my latest post in this thread. We know that the magnetic poles of the Earth are moving. Let’s say (hypothetically, of course) that they begin to move so that in one year time they arrive at the opposite sides of the equator. In the next year, they are reversed, and so on in circle. What should we do? One year we will call the poles North-South, the next year East-West, then South-North, then West-East?!
Wouldn’t that be very confusing?
Shouldn’t we find some other names for them?

[Bored chemist]

But "North" and "South" have no meaning for a magnet.

That's so wrong it's funny.
Hang the magnet from a thread.
The North pole points North and the south pole points South

The words "Plus" and "Minus" are far more natural for the magnetic poles

Obviously wrong, because if those names were more obvious then those names would be used. They aren't.

It cannot be arbitrary, it cannot be a matter of human's convention.

It is.
We even know which human made the choice.

It is like to say, who a male and who a female is, were a matter of convention.

No.
It is like saying that the words "male" and "female" were, like all other words, made up.

It is a school CRT (more precisely Braun tube) just as any CRT in a CRT TV, monitor or oscilloscope.

No, it is not.
A CRT has a vacuum in it to avoid scattering the electron beam.
That tube has gas in it in order to show up the path of the beam.

Could we change the "convention" and reverse the arrows of the Plus and of the Minus. No, we can not.

Yes we could.
And your use of bold text doesn't change that.

It will be unnatural.

Again, just restating your belief isn't going to change anyone's mind. You would need evidence (and all teh evidence says you are wrong).

or this shorter topic "Is the designation "positive" and "negative" in electricity arbitrary?" https://www.thenakedscientists.com/forum/index.php?topic=78171.0

You were wrong then, and you are still wrong now.
Making a second thread doesn't work any better than repetition or bold text.

Similarly, if we touch with an ordinary phase-tester (PT) (one-contact neon test light) two different wires and notice that the lamp of the PT lights up stronger with the first wire than with the second, then we can say that the voltage in the first wire is greater than the voltage in the second.

No
For example, it's perfectly possible that the second case is a higher frequency supply and the capacitive coupling is bigger.
We could say that the brightness of the lamp indicates current.
That's fair enough - at least to a rough approximation.
But there's something weird about neon lamps. They have negative incremental resistance (over the range we are talking about).
So a brighter lamp- with a higher current- actually has a lower voltage across it.

So, as usual, you have shown that you don't know what you are talking about.

What is an electric wind?

Nothing to do with cathode rays.

There are many experimental evidence that the direction of the conventional current is the true direction of the current.

Name one.

[Bored chemist]

My prediction that a non-symmetrical conical tube (mentioned in my OP) would make the beam curved even without an external electric or magnetic field could clear all doubts. I don't have the means to experiment, otherwise I would have carried out this experiment so far.

What shape do you want?
https://en.wikipedia.org/wiki/Geissler_tube

It's obvious that, if the shape of the tube made a difference, people would have noticed a hundred years ago.

You need to explain why they missed it.

[Mitko Gorgiev (OP)]

But "North" and "South" have no meaning for a magnet.

That's so wrong it's funny.
Hang the magnet from a thread.
The North pole points North and the south pole points South

Let's say you go to the moon (which, as is known, doesn't have magnetic poles) and you have to work something there with permanent magnets.
What would be the meaning there of "North" and "South" for the magnetic poles?

[Bored chemist]

What would be the meaning there of "North" and "South" for the magnetic poles?

Convention.
Just the same as the meaning of "North" and "South" on a map of the moon.

It has nothing to do with the fact that cathode rays are, in fact, cathode rays.
Perhaps you should try to stick to the point.

[Mitko Gorgiev (OP)]

What would be the meaning there of "North" and "South" for the magnetic poles?

Convention.
Just the same as the meaning of "North" and "South" on a map of the moon.

It has nothing to do with the fact that cathode rays are, in fact, cathode rays.
Perhaps you should try to stick to the point.

I stick to the point, but others don't.
In this video it is visible with naked eye that the "beam" is a vortex.

From 1:40 to 1:50

[Bored chemist]

In this video it is visible with naked eye

Yes, and, again you miss the actual point.
If it is visible then it is not an electron beam.
It is a beam of charged particles hitting a screen.

And at the start of the experiment you can see that it forms a straight line.
When the presenter turns up the current through the coils and generates a magnetic field the beam curves.
Everyone expected that.There was never any argument about the fact that, in a magnetic field, the electrons follow a curved path.

Instead, try answering relevant questions like

It's obvious that, if the shape of the tube made a difference, people would have noticed a hundred years ago.

You need to explain why they missed it.

Please explain how you still think that a symmetrical environment is important to a straight line trajectory for electrons in spite of the evidence that in (among other things) electron beam welding, they travel in straight lines  even in very unsymmetrical circumstances?

Also, please explain how "nothing" pushes electrons around.

But, we know that (in the absence of a magnetic or electrostatic field) the electrons travel in straight lines.

[Mitko Gorgiev (OP)]

In this video it is visible with naked eye

Yes, and, again you miss the actual point.
If it is visible then it is not an electron beam.
It is a beam of charged particles in low pressure gas.

Stop posting pictures of things that are not electron beams.

As I see the video is from Indiana university and its title is "Magnetic deflection of an electron beam".

[Bored chemist]

The point remains that the beam is straight until the field is turned on.

[Mitko Gorgiev (OP)]

The point remains that the beam is straight until the field is turned on.

Let's say we deform the tube a little with a bunsen burner. Then the straight "beam" will be also deformed even without additional magnetic or electric field.
As I said, I can bet on this. But you don't want to bet. If someone from the members or the guests want to bet, I am ready.

[Bored chemist]

Let's say we deform the tube a little with a bunsen burner. Then the straight "beam" will be also deformed even

That's still wrong.
Because, if it was right you would be able to answer this.
And you can't.

What shape do you want?
https://en.wikipedia.org/wiki/Geissler_tube

It's obvious that, if the shape of the tube made a difference, people would have noticed a hundred years ago.

You need to explain why they missed it.