In outer space there is vacuum, also called nothing. Although that statement is simplified, nothing is nowhere because there will always be something there. There will be gravity field, EM-radiation, neutrinos EM-fields, an atom or more in all kinds of nothing you could think of. It is maybe possible to think of nothing but that nothing must have no space (volum), and that would probably be nothing more than difficult to imagine. Enough about REAL nothing, now more about what most people call nothing: vacuum (or close at least).
Some time ago I presented an idea for my friends: If you take an uninflated helium ballon (the metallic looking type) and seal it while uninflated, then take it out in space you would be able to create a volume of nothing inside the ballon. You could make the balloon look half inflated. Most of my friends could not comprehend this idea, and I had a problem with proving it.
Some months later while playing with an vacuum pump and other physics equipment for demonstrations, an idea emerged. A sylinder with some water in it could be exposed to near vacuum and if vacuum is "nothing" I could move som of that nothing from above water level under the water level just by moving water. So this was done.
I do run a lot of simple physics experiments, and will try to document them better in the future. Could be some nice stories. Coming up: cloud chamber, conservation of mechanic energy, polarized light, waves on a plate, jacobs ladder, transformation of 230Volt.