Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

demondoppel
Lv 5
demondoppel asked in Science & MathematicsAstronomy & Space · 1 decade ago

Why is a vacuum, a vacuum?

For instance, if I remove air from a canister and any matter, why does the canister create a void within it, so that when I open a valve on it, air will suddenly rush in to fill the void?

I know people will mention about atmospheric pressure being involved, to balance the forces between positive and negative pressure. Equalization and such.

How about outer space......then, why is that this negative pressure seem to be everywhere, and what creates it?

thanks very much.

Update:

thanks "Silent".

How does the negative pressure come about though? Regardless if the vacuum is empty....trying to figure this out.

Update 2:

thanks "Doug"....

Okay here's another thought. Huge expanses between stars. No matter, Just void. And yet there is vacuum present. Would it be those distance stars creating the vacuum, as what you said about mass creating the conditions?

Or is this something else? thanx

Update 3:

Aether is an interesting twist....but it still doesn't explain how, within a void, that negative pressure would exist.

If we open out door on our craft while in outer space, all the air rushes out of the door into space. It's like the 'void' is pulling all matter.

Can this void be acting like a 'black hole' or a singularity, in which is draws things unto it's self.....and then the question is, how?

3 Answers

Relevance
  • goring
    Lv 6
    1 decade ago
    Favorite Answer

    Vacuum is the absence of air in a container. If the container does not exist then the vacuum does not exist either.

    In Physics the word vacuum is used to describe the speed of light in space. Hence space is considered a vacuum. But is it? that is the question.

    Does a void exist in a vacuum.This bring the substance of space which was called by Classical physics as the Aether, and is called to day" space time"(what ever is meant by that).

    So if Space is a void and there is no container to hold it ,then space would not exist.That means that there is no time in space. And light would be traveling in a timeless space.

    Since the definition of velocity is space traveled over time then it is likely that a substance of space exists that is necessary to create the pressure to contain mass in their own structures.

    Hence space is not a void.That is what was meant by the Aether.

    Note ; a bird could never fly in a vacuum. and nothing could exist in nothing.

    note on Pressure;

    To every pressure there exist and equal and opposite pressure.

    Source(s): The substance of space time The reality of the Aether Quantron theory Me own little brains
  • doug_donaghue
    Lv 7
    1 decade ago

    It's not a 'negative' pressure, it's a total lack of pressure. And it's that way because that's the normal state of things. It's only when you get enough 'mass' in one place that gravitational acceleration creates 'pressure' within a gas.

    As for -why- it's a vacuum.... It was called 'vacuum' because 'chicken soup' had already been taken.

    Doug

  • Silent
    Lv 7
    1 decade ago

    Simple answer: if you take everything away, there's nothing left. That's what a vacuum is: nothing. Nothingness doesn't need to be "created". It's what's there when there isn't anything there, if that makes any sense.

Still have questions? Get your answers by asking now.