I’ve had a lot of lonely and soulful nights lately giving me the chance to think about how precarious life really is. In those quiet times of contemplation one has the chance to ask what is this all about. What is nothing and does the world require things so that “nothing” can be understood.
What is nothing?. I know this sounds like a frivolous question. After all, we think we all have an intuitive sense of nothingness. But when we actually try to answer this question – it is an extremely, extremely question to answer. Everywhere we look, there is something there.
If we were to remove everything out of a box - the dust, the dirt, the air, every last single atom., what then exists in the box. Is it really nothing? Why this maters is because emptiness makes up almost the entire universe. More so, it’s possible that understanding emptiness might help explain the origin of the universe, everything, and perhaps even why we exist at all.
Ever since the early 20th century when the strange structure of the atom was revealed each additional insight has fed into a radical new picture of how nature works at its smallest and fundamental level. A quantum mechanical description in which, against all common sense it seems to make it impossible to ever truly have nothing.
At the most fundamental level Nature is itself based on uncertainty. Heisenberg's Uncertainty Principle is usually expressed in terms of momentum and position. That is the more precisely the position of some particle is determined, the less precisely its momentum can be known, and vice versa. However, this Uncertainty Principle can also be expressed in terms of energy and time.
And this is the rub. In theory, if we were to examine a very small section of an empty space we could in principle determine how much energy is in that space very very precisely. However, if we slow down time - Heisenberg's Uncertainty Principle tells us something very bizarre. It suggests that at these levels the uncertainty is so great that there is enough energy to create particles literally out of nothing at all.
So in truly tiny intervals of time and space something could be created from nothing. The truly bizarre implication is that quantum fluctuations may create and destroy matter. Some say that energy is borrowed from the future, particles are created, destroyed and the debt repaid quickly.
From this, the most jaw dropping idea of all is that matter we think of in the every day world - everything we see and feel might be nothing but the left over froth of particle creation and destruction.
One of the most profound and beautiful ideas in science and philosophy therefore is that quantum reality has shaped the universe we see today. Our universe may be nothing more than a quantum world inflated many many times out of quantum fluctuations.