B Does the Torricelli Vacuum Experiment Prove the Strength of Vacuum Forces?

[Rotating Wave]

Glass does flow and examples can be seen in e.g. in antique windows where, however, it has taken several centuries at ordinary temperatures. I would think that in good quality laboratory glass it is slower.

Something like your question about light did exercise early scientists. Some of this is by memory, however certainly Robert Boyle (second half of 17th century) developed a pump where you could actually achieve and work with a decent vacuum. As has been pointed out, this is a question of degree and you can never get a perfect vacuum, Boyle could just get a better one in a larger volume than anyone ever had before.This allowed him to clarify things that were not clear before, but that we take for granted and suppose to be obvious.Even the idea that air is a substance was only emerging, and that there were other gases than air was clarified only slowly. I'm pretty sure that it was Boyle who shook a bell inside his vacuum and found that no sound was heard. From this he concluded that the substance, air, was needed for the transmission of sound. On the other hand he could see still see the bell inside the vacuum in the glass container. So either nothing was needed for the transmission of light, or there was still some other substance through which it could be transmitted. When a couple of centuries later there came to be a better theory of light, they still could not get over this idea and postulated that there was some mysterious pervading substance, a very unsubstantial substance to which they gave the somewhat mystical name Aether, through which light waves could be carried a bit as airwaves carried in air. They made calculations about this aether which have finished in the dustbin of scientific history, And these days we are clear that we do not need any aether and that the light is all carried on fields, which we all understand extremely well, they are, well we all understand them extremely well.

On this matter... Doesn't that mean that a "field" IS the aether they were looking for? I mean, they were looking for the medium light is carried through, and we now know it is carried on fields, so we basically just renamed 'aether' to 'field', right?
And, I did not know about this experiment, but I did know about the concept of the aether. But I will investigate this experiment because it looks to hold much information.

 

[Rotating Wave]

Do I spot a contradiction here ?

You do a pretty good job yourself ! (*) :
but here you derail spectacularly:
$$ F = G_k{m_1 m_2\over r^2}$$ where $F$ is the magnitude of gravitational force, the equivalent of '$F\,$' in $F=ma$ !

And $G_k$ is not a force but the gravitational constant with a completely other dimension. The value of $G_k$ says something about the relative strength of gravity.

Yes, apparently.

mass.
(*) in the sense that you describe the effects. To a very large extent, that is what physics is all about.

The questions 'why' and 'what IS it ?' are better left to philosophers.

Have to hand it to you, you ask some pretty tough questions !

I'm sorry about the tough questions thing. I didn't know they would be tough when I asked them.
I'm just trying to piece things together. I haven't been near information for very long and am trying to catch up.

 

[Rotating Wave]

Do I spot a contradiction here ?

You do a pretty good job yourself ! (*) :
but here you derail spectacularly:
$$ F = G_k{m_1 m_2\over r^2}$$ where $F$ is the magnitude of gravitational force, the equivalent of '$F\,$' in $F=ma$ !

I am confused to how this is different than what I said: "...where G is the magnitude of gravity, Gk is the constant force of gravity, or the equivalent of 'a' in F=ma, and 'm' is the product of two masses per the square of their radius."
If G_k is not F, and {m_1 m_2\over r^2} is not F, then G (the magnitude of gravity, or gravitational force) would also be F, so I was saying also that G is F. So I am not sure how I derailed on that one. Please clarify?

 

[BvU]

G is not the magnitude of gravity. It is the magnitude of the gravitational force.

$G_k$ is the gravitational constant. It is NOT the equivalent of $a$ in $F = ma$.
The dimension of $G_k$ is length³ x mass^-2 x time^-2, units Nm²/kg².
The dimension of 'a' is length x time^-2, units m/s² .
Totally incomparable.

And 'm' is a mass, in kilogram, NOT the product of two masses divided by the square of their distance: the latter has a dimension kg²/m², which is incomparable.

 

[BvU]

In a textbook you can find the equivalent you are seeking:

If we use the mass and radius of the earth, we can write $$g = {G_k\, m_{\text earth} \over r_{\text earth}^2}$$ and THEN $g$ is an acceleration and $mg$ is a force.

https://en.wikipedia.org/wiki/Gravitational_constant#Definition

$\$

 

[Rotating Wave]

G is not the magnitude of gravity. It is the magnitude of the gravitational force.

$G_k$ is the gravitational constant. It is NOT the equivalent of $a$ in $F = ma$.
The dimension of $G_k$ is length³ x mass^-2 x time^-2, units Nm²/kg².
The dimension of 'a' is length x time^-2, units m/s² .

And 'm' is a mass, in kilogram, NOT the product of two masses divide by the square of their distance: the latter has a dimension kg²/m², which is incomparable.

Ok. I see! Thank you. I guess I have more studying to do.

 

[Rotating Wave]

In a textbook you can find the equivalent you are seeking:

If we use the mass and radius of the earth, we can write $$g = {G_k\, m_{\text earth} \over r_{\text earth}^2}$$ and THEN $g$ is an acceleration and $mg$ is a force.

https://en.wikipedia.org/wiki/Gravitational_constant#Definition

$\$

Yeah, I need to study more. It makes sense. I appear to have concepts mixed up. I didn't realize G_k had a different dimensional property though, now I can see how I should have known from reverse engineering the math.
Ok. So it looks like I'll be hitting the basics again to solidify the concepts.

 

[StandardsGuy]

answers: nothing ( !)
Actually there is a very low pressure water vapour. So low that it's a vacuum for our perception.

I disagree. A vacuum contains all the laws of the universe. It may be in the form of fields such as the Higgs field. That's a lot more than nothing.

 

[BvU]

A vacuum contains all the laws of the universe

Don't forget dreams, hope and charity.

I wholeheartedly disagree, but you are entitled to your opinion. Any experimental evidence ?

 

[Rotating Wave]

Don't forget dreams, hope and charity.

I wholeheartedly disagree, but you are entitled to your opinion. Any experimental evidence ?

I think I get what Standards guy is saying. Space is a vacuum and holds all of the laws of the universe (because it basically IS the universe), so any artificial vacuum - like Torricelli's - would have those same traits, including fields.
In that case, space is the experimental evidence of a vacuum having all the laws of physics.
I think that's what they were saying...