Not sure if this has been done before or not, but one thing I don’t quite get is the idea of empty space - how can there be ‘nothing’ in between planets/stars/galaxies etc (or even inside atoms in between the nucleus and the electons etc for that matter). How can anything ‘travel’ through ‘nothing’ (light, rockets etc)?
I know there used to be a theory of the ‘ether’ as a substance that filled in the gaps - are we moving back to something similar with ‘dark matter and dark energy’?
I’ve read of a thing called ‘the fabric of space-time’ (as in supposedly the thing that is ‘bent’ by heavy objects thus causing gravity - another mysterious topic) - but what is it MADE of?
Think of space as a measure of volume. You have so much “space” in your room or there is a brain in the “space” between your ears. The concept of nothing isn’t hard to grasp. Think of it the same way you would your room. Your room represents the entire known universe (but a bit smaller). Lets say your TV represents the sun, and your bed represents the Earth. Other than those two items, you have nothing else (representative furnature) in your room. Now, the TV (sun)and your bed (Earth) occupy some space in your room universe, but the rest is empty. Empty, as in not inhabited by matter or La-Z-Boys. The lack of substance to fill space doesn’t effect the volume of that space. The dimensions of your room don’t shrink when I steal your TV, but you have more volume available because you now regained the room the TV displaced.
As far as traveling through “nothing”, that’s sort of relavite. We don’t need a medium to travel through space. It’s different than swimming or walking. Instead, since there is no friction to push off of, we use inertia and other really cool hockus pockus to get to the moon.
[sub]*note - I understand that the room/universe model is technically wrong, but come on!![/sub]
oliverar - As for traveling through ‘nothing’, you are part right. Heat and sound cannot travel through nothing as they requires a medium to transfer through. Light on the other hand, travels much better through ‘nothing’ as it behaves partially like a partical (photons) and those particles don’t have anything to collide with and slow them down. Once they do collide with something (like a planet) some of the energy is converted to heat energy and the object warms up.
Rockets travel though space because they eject mass out the back in the form of hot gases. Since every action has an equal an opposite reaction, the rocket moves in the opposite direction the gasses move. It does not push against atmosphere or anything.
Let me get that nit for you <pluck!> There we go.
Heat sure does travel through empty space. What do you think infrared radiation is? Stand out in the sun for a while - here in Arizona if possible - then tell me all the heat energy from the sun can’t traverse the 93 million miles of near vacuum between here and there.
You may be thinking of heat transfer by condution where two objects are touching or convection where heated gasses move about.
There are all kinds of atoms and molecules, mostly gasses floating around in all that empty space you inquired about.
The vacuum of space is the source of all electricity per Tom Bearden.
Check out his web site and solve the world’s energy problems.
You probably shouldn’t be directing the OP to websites like that… He might not know that he shouldn’t take such claims seriously.
As for radiant heat transfer, it’s not just infrared. Any electromagnetic radiation will transfer energy in the same manner, with hotter objects transferring more at higher frequencies. A human body or a campfire will radiate mostly in the infrared, but the Sun radiates mostly in the visible range, and a young neutron star will radiate in the X rays. It’s the same process in any of these cases, and one shouldn’t say that only infrared is heat.
But to address the OP, it might be better to ask why things wouldn’t be able to travel through vacuum. What’s there to stop them? It’s not like I’m going to slam into a vaccum like it was a brick wall.
What about quantum material? Woulnd’t that be filling the “empty spaces?” I just can’t seem to wrap my mind around the idea that there are voids with “nothing” in them.
I guess that depends on your definition of “quantum material”. If you remove the “quantum material” from a specific volume of space so that it is “empty”, the part of the universe occupying that space f doesn’t cease to exist simply because there is nothing in it. The the concept of empty and nothing are relative because you have to have a something somewhere to have a nothing somewhere else.
Maybe it would help to visualize the alternative; a universe in which every single space, from intergalactic down to subatomic, was jam-packed with solid matter, with no “nothingness” in between. The first problem I see is that we’d have a static universe, with nothing able to move or expand.
We need that “nothingness” as much as “somethingness.”
For me, it’s the opposite. Empty space is simplicity itself. Nothing could be more elegant. It’s all that other junk that demands a full accounting.
Or putting the question as it’s traditionally put: Why is there something instead of nothing?
>Heat sure does travel through empty space. What do you think infrared radiation is?
I think it’s infrared radiation, a form of electromagnetic radiation. It isn’t heat. It’s radiated by warm matter (as is visible light and xrays and so forth per the other post).
Heat is energy in the form of random motion of atoms and molecules. When atoms and molecules in motion radiate EMR by virtue of their nonuniform charge distribution, it’s a conversion into another form of energy.
Heat and EMR are certainly related in various ways but they aren’t the same thing. There is an expression, “radiant heat”, in the vernacular, so I guess you could say there is an alternate popular definition of “heat” that includes EMR, but I think that’s not an appropriate usage in a technical discussion.