This is the whole point. You and I, and likely every single person on this forum, haven’t a clue of how advanced quantum physics / mechanics has progressed. Don’t take this the wrong way, but we don’t know jack. I try to read as much as I can, and I have to admit, it is all very heavy reading, very difficult to follow and I think I grasp enough as to understand what is being discussed.
First a very basic and decent laymans explanation from
forums.techguy.org/random-discussion/49168-how-can-nothing-unstable.html
"It is all very confusing, but I believe the way it is explained is that experiments show that nature does indeed hate a vacuum [especially Hoover’s

]. If you manage to get down to absolutely nothing, then nature will take over and you will spontaneously get a particle and an “anti-particle” - - all of which still adds up to nothing [like Mulder’s arguments] but, it is a more interesting “nothing”.
If you reallly want to drive yourself crazy over this topic, I suggest the book “Nothingness: the Science of Empty Space” by Henning Genz. Reading it is tough sledding, but a good read if you manage to battle thru it.
“nothing” is unstable because “nothing” is equal to a vacuum. Nature wants to fill the vacuum or, in this case, end the nothing. The preferred state of a nature is chaos (not to be confused with Chaos the evil organization in “Get Smart”)which is 180 degrees from “nothing”."
If you do like to learn new things, like how a state of nothingness is highly unstable and what this means, here is a more complicated, but still readable explanation from…
csicop.org/sb/2006-06/reality-check.html
Why is there something rather than nothing? …Why There Is Something Rather than Nothing, philosopher Bede Rundle calls it “philosophy’s central, and most perplexing, question.” His simple (but book-length) answer: “There has to be something.”
Clearly, many conceptual problems are associated with this question. How do we define nothing? What are its properties? If it has properties, doesn’t that make it something? The theist claims that God is the answer. But, then, why is there God rather than nothing? Assuming we can define nothing, why should nothing be a more natural state of affairs than something?
In fact, we can give a plausible scientific reason based on our best current knowledge of physics that something is more natural than nothing! …
Suppose we remove all the particles and any possible non-particulate energy from some unbounded region of space. Then we have no mass, no energy, or any other physical property. This includes space and time, if you accept that these are relational properties that depend on the presence of matter to be meaningful.
While we can never produce this physical nothing in practice, we have the theoretical tools to describe a system with no particles. The methods of quantum field theory provide the means to move mathematically from a state with n particles to a state of more or fewer particles, including zero particles. If an n-particle state can be described, then so can a state with n = 0.
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In the current universe, bosons outnumber fermions by a factor of a billion. This has led people to conclude that the vacuum energy of the universe, identified with the zero point energy remaining after all matter is removed, is very large. A simple calculation indicates that the energy density of the vacuum is 120 orders of magnitude greater than its experimental upper limit. Clearly this estimate is wrong. This calculation must be one of the worst in scientific history! Since a non-particulate vacuum’s energy density is proportional to Einstein’s cosmological constant, this is called the cosmological constant problem.
Instead of using numbers from the current universe, we can visualize a vacuum with equal numbers of bosons and fermions. Such a vacuum might have existed at the very beginning of the big bang. Indeed this is exactly what is to be expected if the vacuum out of which the universe emerged was supersymmetric-that is made no distinction between bosons and fermions.
This suggests a more precise definition of nothing. Nothing is a state that is the simplest of all conceivable states. It has no mass, no energy, no space, no time, no spin, no bosons, no fermions-nothing.
Then why is there something rather than nothing? Because something is the more natural state of affairs and is thus more likely than nothing-more than twice as likely according to one calculation. We can infer this from the processes of nature where simple systems tend to be unstable and often spontaneously transform into more complex ones. Theoretical models such as the inflationary model of the early universe bear this out.
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What this example illustrates is that many simple systems are unstable, that is, have limited lifetimes as they undergo spontaneous phase transitions to more complex structures of lower energy. Since “nothing” is as simple as it gets, we would not expect it to be completely stable. In some models of the origin of the universe, the vacuum undergoes a spontaneous phase transition to something more complicated, like a universe containing matter. The transition nothing-to-something is a natural one, not requiring any external agent.
As Nobel Laureate physicist Frank Wilczek has put it, “The answer to the ancient question ‘Why is there something rather than nothing?’ would then be that ‘nothing’ is unstable.”