yes you can.

We take a closed glass tube from one side. Fill this tube with water. Turn the tube inside a large basin with water from the open side. The water at the top of the tube will drop by a perpendicular rate. Pressure at the top of the tube will be zero

Laith,

The headspace above your column of water contains water vapour. It is not a vacuum: at room temperature it is a rather large pressure of about 30mbar.

So, is it possible to make an absolute zero pressure?

Why can't we make it?

Pressure from particles could be set to zero by removing all the gas in a small container with a top quality vacuum pump (it' really difficult but has been done I think). However even then the walls are at some none zero temperature so there is thermal radiation in the container which would create a small radiation pressure. Finally, even if you could cool the walls to a very low temperature, there is "vacuum energy" within the container. The only way to exclude that is to make the walls very close together, look up the "Casimir Effect" for more on this.

Nazaruddin,

You cannot practically achieve it because every material has a finite diffusivity. And no pump is perfect.

Sure. Run a turbo pump. You remove most of the air and achieve 10^-6mbar.

Well done.

You now discover that most of the gas being pumped away is water - that was stuck to the stainless steel of the chamber.

So you bake the chamber - and most of the water goes away.

Now run a sorption pump - and you might get down to 10^-9 mbar.

Wonderful.

But now you discover that hydrogen *leaking through the stainless steel* is the main gas you are pumping away.

Yes, steel can allow gas to diffuse through it. Like *any* metal, given enough time.

So. Unless you can propose a material that is utterly impermeable to a gas, *and* have a perfect pump, a perfect vacuum cannot be achieved.

Note, that *everything* has a vapour pressure at a non-zero absolute temperature.

Including metals.

Thanks Garry, it's a good comment....

Hello Tapan, are you there?

Please give your comment. Thank you...

Based on this discussion, do you agree if we conclude that we cannot make the pressure absolutely zero? Please answer.

Thank you.

Nazaruddin,

The question is akin to asking: can we make a cavity that has no quanta in it?

(ie, at absolute zero)

The answer is 'no'. One can conceive of such a thing, but it cannot be made.

I wonder what type of research you are engaged in that prompts this question.

Dear Researchers,

Have a nice weekend with your family....