Is there a perfect vacuum between atoms in space?

[Naty1]

A definition of "vacuum" would clarify this discussion...

Wikipedia makes some good points here:

http://en.wikipedia.org/wiki/Vacuum


In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure... the classical notion of a perfect vacuum with gaseous pressure of exactly zero is only a philosophical concept and is never observed in practice. .

The quality of a vacuum refers to how closely it approaches a perfect vacuum... Quantum theory sets limits for the best possible quality of vacuum, predicting that no volume of space can be perfectly empty. Outer space and interstellar space are naturally occurring high quality vacuums, mostly of much higher quality than can be created artificially with current technology. ...

 

[mugaliens]

True - vacuum is defined as "the absense of matter," not the absence of energy.

Fermions ("matter"), however, include the six quarks, the six leptons (which include neutrinos, electrons, and muons), as well as the four bosons (which include photons, etc.)

Thus, the question becomes - is there anywhere in space actually devoid of matter (fermions)?

The answer is no. There is no place in the universe where a perfect vacuum can be achieved, as the universe is awash in a flood of photons and neutrinos, both of which constitute matter.

The next question is "can zero pressure ever be achieved anywhere in the universe?" and the answer to that question is also "no." Even in intergalactic space, there are ~ 10^-6 molecules per cm³, and that's about twelve orders of magnitude fewer than we can achieve here on Earth. But it is still a non-zero value, and there is still pressure exerted by those few molecules which remain.

Let's assume we had a widget which would sweep aside all fermions within a closed, non-sublimating container. Even then we would not have a perfect vacuum due to quantum fluctuation and the fact that for some of the pairs, one appears on one side of the boundary and the other appears on the other side of the boundary.

However, we could achieve a perfect vacuum if we could engineer a reverse black hole, a "white hole," with an event horizon greater than 0 above it's center. That would repel all matter of all types and render a perfect vacuum below its event horizon.

To date, however, studies have shown this to be an impossibility, so we're back to "no" for the answer "can a perfect vacuum ever be achieved, either by us or anywhere in the universe?"

No.

 

[Pythagorean]

Photons can get ionized? I'd think atoms got ionized (lose/gain electrons).



If that were true then you could never have a vacuum unless it were in complete darkness and at absolute zero.

I'm pretty sure any normal definiton of vacuum includes matter only.

In the previous post, I had quoted: "ionized" to illustrate that it was an analogy for charge separation (I was at a loss for the correct word: polarized).

Anyway, I was referring to a photon splitting into a positron-electron pair under a large potential difference. I guess then, that what this means to me, is that vacuum doesn't mean "empty space" or "nothing".

 

[JDługosz]

Fermions ("matter"), however, include the six quarks, the six leptons (which include neutrinos, electrons, and muons), as well as the four bosons (which include photons, etc.)

Thus, the question becomes - is there anywhere in space actually devoid of matter (fermions)?

I agree, you can't keep the neutrinos out. However, their total mass is very small, and they may not disturb your experiment.

 

[pavew]

I think I found the way to create perfect vacuum (no gas or any other atoms in container). By mining that I have found the theoretical, mechanical way, to isolate certain area of space. In practice, quality of vacuum would depend on materials used and achieved precision. Would creation of such device do any good for science? Is it worth anything making it?

 

[JaredJames]

In space or on earth?

Creating a perfect vacuum in space is pretty much useless to us.

That aside, how exactly did you go about it? Or is that a trade secret?

 

[CheckMate]

The problem with this discussion is that the terms "vacuum" or "matter" should have been defined and understood before asking questions.

 

[JaredJames]

The problem with this discussion is that the terms "vacuum" or "matter" should have been defined and understood before asking questions.

Well ignoring the previous debate, pavew has outlined exactly what (s)he considers it to be and so I'm awaiting a response on that matter.

 

[pavew]

On earth. Capacity of the container may by between 1 litre and swimming pool size, depends on the budget and size of available shed in which device is manufactured (garden shed - NASA shed :-).

It might be a trade secret, don`t know yet.

I wonder if this kind of perfect vacuum might be useful for like a quantum mechanics experiments / observations?

 

[JaredJames]

What maths or experiments have you done to show you will get a perfect vacuum?

What time frame for said perfect vacuum to be created?

Without sounding harsh, there's a flaw in this somewhere, but I'm not sure if you are able to spot it.

 

[Rebooter]

No, a vacuum does not need to be free of energy; it need only be free of matter.

Blech... this is disgustingly muddy to me.
I'm very uncomfortable with the classical definition of matter.
Is a neutrino matter? is a photonic Bose-Einstein condensate matter?

 

[pavew]

I only wonder if this is worth involving time and money, starting with calculations and making prototype. Would it be useful for anyone?

 

[JaredJames]

I only wonder if this is worth involving time and money, starting with calculations and making prototype. Would it be useful for anyone?

A perfect vacuum would be incredible and definitely worth the time and money - but I doubt you've come up with a way to do it, especially seeing as you haven't done any calcs and this is what appears to simply be an idea on your part.

Ideas are all well and good, but the devil is in the detail. Which is something I think you need before proclaiming you have found a way to create a perfect vacuum.

 

[pavew]

There is only one way to find out - an experiment. Just look around you. Ceramic mug, plastic pen, computer cable, air plane on the sky, this all were just an ideas, all with devil in the detail.

The way I am going to make a vacuum is a bit different than "normal" ones. There will not be any gas since very beginning of the process.I said "I think I found..."

 

[JaredJames]

I assume your method would be similar to taking two pieces of metal sandwiched together as tightly as possible, having four others arranged around them in a cube.

Imagine a cube but with two opposite ends pushed together in the centre.

Then by using two rams you simply pulled them apart, leaving you a cube with "a perfect vacuum".

Sort of like having a fully deflated balloon and increasing its internal volume from zero to X - leaving you a vacuum inside.

This of course only works on the basis that no molecules are trapped initially between the layers and that all seals are perfect, amongst other things.

This kills it for me:

There will not be any gas since very beginning of the process.

How can you start with no gas in the very beginning if we can't get a perfect vaccum?

Or more to the point, if you have no gas then why would you need to do anything further? You've already got your perfect vacuum.

 

[Gabe21]

I think when someone who isn't a specialist talks about vacuum, he means "an empty macroscopically-sized space". If we stick to this meaning, then the perfect vacuum only exists between interstellar space - if, of course, it is not disturbed by all the particles previous posters have listed.[/QUOTE]

a perfect vacuum can only exist in space assuming dark matter(which is everywhere) isn't actually matter. but we don't currently know enough about the physical properties of dark matter to come to any conclusions.

 

[JaredJames]

I think when someone who isn't a specialist talks about vacuum, he means "an empty macroscopically-sized space".

As per the scientifically accepted definition.

If we stick to this meaning, then the perfect vacuum only exists between interstellar space - if, of course, it is not disturbed by all the particles previous posters have listed.

As I understand it there isn't anywhere truly devoid of matter, just areas where there's only a few particles per cubic metre.

 

[Gabe21]

if u had a chamber of matter(doesnt matter the density) and removed all the heat until u reached absolute zero, would that chamber be considered to be in a perfect vacuum?

 

[JaredJames]

if u had a chamber of matter(doesnt matter the density) and removed all the heat until u reached absolute zero, would that chamber be considered to be in a perfect vacuum?

Would the it still be considered matter? If so, no it would simply be very cold matter.

 

[Gabe21]

yes. it would be matter in the solid form but because of the temp their would be no molecular movement of the atoms. so y wouldent it be a vacuum?

 

[JaredJames]

yes. it would be matter in the solid form but because of the temp their would be no molecular movement of the atoms. so y wouldent it be a vacuum?

Because there is nothing in the definition of vacuum relating to heat or the vibration of molecules.

A vacuum simply lacks matter. If there is still matter there, then it isn't a vacuum - hot, cold or otherwise.

 

[Gabe21]

ah. but if temp and pressure are directly linked then when u reach absolute zero shouldent their be a perfect vacuum pressure wise? if no, then is it true if u managed to create a perfect vacuum and introduced a steel ball bearing into that vacuum it would increase the pressure?

 

[JaredJames]

ah. but if temp and pressure are directly linked then when u reach absolute zero shouldent their be a perfect vacuum pressure wise? if no, then is it true if u managed to create a perfect vacuum and introduced a steel ball bearing into that vacuum it would increase the pressure?

A vacuum is defined as an area with no matter in it. Nothing to do with pressure.

Low pressure is simply a side effect of having too few molecules whizzing around.

 

[jollyPHYSICS]

A perfect vacuum would be great. Atleast some corrections can be made on most constants.
Though most ppl might consider it useless. But it very useful to us in the elementary world.

By the way, can some1 help me really explain 'michaelson's experiment' in measuring the 'speed of light'? Using prism and glass over a distance, d, and time, t=1/(Nf).
The truth is that I want to carry out that same experiment (exactly the same way).

 

[JaredJames]

By the way, can some1 help me really explain 'michaelson's experiment' in measuring the 'speed of light'? Using prism and glass over a distance, d, and time, t=1/(Nf).
The truth is that I want to carry out that same experiment (exactly the same way).

You need to start your own thread for this.

 

[PhanthomJay]

Hi there,

Alright, but what about all the space between the flowing neutrons, electrons, muons, and neutrinos. There is still a great amount of space left, and therefore, empty space left.

Cheers

I like Einstein on the concept of Empty Space:

Note to the Fifteenth Edition ('Relativity')

"IN this edition I have added, as a fifth appendix, a presentation of my views on the problem of
space in general and on the gradual modifications of our ideas on space resulting from the
influence of the relativistic view-point. I wished to show that space-time is not necessarily
something to which one can ascribe a separate existence, independently of the actual objects
of physical reality. Physical objects are not in space, but these objects are spatially extended.
In this way the concept "empty space" loses its meaning."[/color]

June 9th, 1952 A. EINSTEIN