Complete Removal of Matter from Space

[brookssp]

What is left if all matter and energy is removed from a particular region in space?

For example, say I completely remove all of the matter and energy from a region of the air in front of me (also assuming no matter or energy moves in and out of this space once I do this), then what is left?

 

[Meizirkki]

Because the scenario is absurd, it's a question impossible to answer. May I ask why you're so curious about that?

 

[brookssp]

Someone brought up when discussing origins of matter in Cosmology class. I know other people have thought about it before and have possible opinions/logic to it even if it is absurd (which it is but it does lie at the heart of the origin of matter). I suppose it could be construed as a philosophical question but was interested in what others thought.

 

[Meizirkki]

What comes to my mind is an area where there is absolutely nothing and is at temperature of absolute zero. But I'm wondering whether such area can exist even in theory.

 

[brookssp]

That is exactly what I'm wondering too. I know it's not empirically possible but could it be theoretically possible?

 

[Meizirkki]

Imho, such area is the very definition of non-existence. If there's no mass nor energy it does not exist.

 

[HallsofIvy]

What is left if all matter and energy is removed from a particular region in space?

For example, say I completely remove all of the matter and energy from a region of the air in front of me (also assuming no matter or energy moves in and out of this space once I do this), then what is left?

You mean removing the air from "a region of the air in front of me", right? Then you will have, macroscopically, a vacuum but, microscopically, there will be elementary particles popping into and out of existence all the time.