Did you know that the entire population of our world can fit inside a sugar cube, if we could somehow remove all the empty spaces inside?
The world around us might look solid to touch and feel from the outside, but it is largely empty in a manner of speaking. Rutherford's gold foil experiment systematically proved that 99.9 percent of its mass is concentrated at the centre, while the rest is surrounded by electrons orbiting. As a result, we have learned that 99.999% of its volume is nothing more than vacuum.
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Logically, this means that since everything is made up ultimately of atoms, 99.999% of the entire universe is empty.
But is this empty space inside atoms vacuum? Not quite. What’s so strange about this space occupied by electrons is that it is both empty and not. Despite knowing the bounds of space within which electrons exist i.e. outside the nucleus and inside the atomic radius, we can't pinpoint its exact location. So where is it really?
Instead of moving in fixed well-defined paths, like the planets in our solar system, they move arbitrarily within its own orbital governed by nothing more than the "law of probability".
Yes! That's right.
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The probability of an electron's existence at a fixed point inside the orbital is given by a wave function. However, when electrons are actually measured, this entire probability wave collapses into a single definite value where it is found. It can be argued that electrons exist simultaneously inside the entire space in varying proportions at the same time, but also not. This strange behavior is a consequence of wave-particle duality of an electron which is essentially a theory that proves electrons to behave both like a wave and matter.So, to answer this question accurately, drawing a parallel to Schrodinger’s cat, the empty space inside an atom is both empty and not.
