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DISCLAIMER
The methods described in pages are a theoretical discussion ONLY. Methods are discussed in only the broadest terms and I hold no qualifications in the fields discussed.
Because a method is listed here does not indicate that I approve or recommend it. In some cases, I definitely don't!

Spontaneous Quantum Tunnelling is something I thought I'd add just for fun. It's Galactic Lotto on a scale so large that conventional mathematics simply gives up. I'm going to talk about the subject very loosely, so students of Quantum mechanics, please: take this as a bit of fun and don't point out my inaccuracies!

This method is completely possible. The snag is that the chances of it happening are so utterly close to zero that the universe would probably have to live several times its current age for it to ever happen. But, to quote the National Lottery catch-phrase, "It could be you!"

A clever guy called Newton once noticed that physical phenomena seem to follow consistent rules and wrote these down. Newton’s Philosophić Naturalis Principia Mathematica became the basis of what we now know as Newtonian Science, and for nearly three hundred years, most scientists smugly thought this was the final word in describing the universe and how it works.

However, the universe isn't that much of a pushover. Newtonian science is great for describing what happens to an apple when you drop it, or for plotting rocket trajectories between planets, but there are limits: there is a point at which discrepancies begin to crop up, and phenomena occur that classical science can only shrug at.

Here's an example. Nuclear radiation is a well-observed occurrence. It comes in three forms: Alpha, Beta, and Gamma. Let's look closely at alpha radiation. An alpha particle is almost indistinguishable from a helium atom: two neutrons and two protons. It appears when a larger atom undergoes alpha decay. How it does that isn’t important right now, but the thing is this: a large atom has spawned this little alpha particle. The parent atom has binding forces which bind its dependents to it like a planet holding on to its satellites. According to classical Newtonian science, a particle will only escape if it has enough kinetic energy to overcome these forces: if it doesn’t, we’d never see it, and it just so happens that an alpha particle doesn’t have that kind of energy. In other words, according to our everyday expectations based on “falling apple physics”, alpha decay can never actually happen: it’s physically impossible for the alpha particle to ever escape its parent.

But alpha decay still occurs, so what is going on here? Enter Quantum Mechanics.

Quantum Mechanics is a wonderful subject. Trust me on this: the mathematics is frightening, but the sheer mind-bendingly counter-intuitive concepts it leads to are well worth it (and you very seldom have to work out the maths yourself). It practically yells out, "Hey guys! There is such a thing as magic!"

QM works by describing things in terms of probability functions. You have a particle bouncing about in a box: there is a probability function to describe where it will be at any given time. Probability functions are very strange things, because they can lead impossibilities… uh, no, let me rephrase that: they can lead to things that sound impossible if we consider them in a classical way. For example, a system can exist in two (or more) mutually exclusive states at the same time. For example: buy a lottery ticket. DON'T check the numbers, or listen to whether anyone else has won the jackpot. Until you check the numbers or witness your neighbour showing off his new Ferrari Enzo, you don't know whether you have won or not. Therefore you are in two states: you have both won and not-won the lottery: there are two potential states, normally mutually exclusive (they contradict each other) existing at once. The probability is, of course, that you haven't won, but the possibility exists that you have. This is the essence of the famous Schrodinger's Cat experiment; a (strictly!) theoretical argument that illustrates how any multi-outcome experiment has the potential for all possible outcomes until you actually look at the results. Mathematically, each outcome would have a probability wave function describing how likely it is to occur.

QM gets weirder. Under certain conditions, impossible events can happen. If you look at the probability function for the position for our alpha particle for instance, we see that the probabilities vastly favour the particle not being able to escape its parent, as expected by Newton and co, but there is a tiny but non-zero chance that the particle may be found outside the force-barrier that contains it. And this is what we actually see: most alpha particles do not escape, but some do, just as if they were tunnelling through the wall of forces that ought to stop them. This isn't a mathematical trick or a quaint scientific illusion: matter actually does behave in ways which defy classical physics.

Scaled up, the same principle will apply: a tennis ball thrown at a concrete wall will sometimes 'magically' pass through it - if you're prepared to wait a million billion years or so for every atom in the tennis ball to coincidentally tunnel at the same time. The event is so unlikely, our chances of ever observing it are absurdly remote, but like winning the lottery, the chance isn't zero.

So how would this turn us into a horse? Well, the upshot of tunnelling is that all entities have a small chance to move where they aren't expected. The larger and more complicated a collection of particles gets, the more improbable it becomes that such an event would be observed (Winning the lottery is a slim chance, but we're talking about winning it every week for a thousand years: compute the chances of that!). By the time you've reached the size of something big like, say, a smallish molecule, the chances of the unexpected become vanishingly small. This is exponentially the case for a macro object like a human-sized creature. Nevertheless, there is a non-zero probability that all the atoms in your vicinity could, just maybe, decide to spontaneously switch about in just such a manner as to turn you into a horse. The chances are (and the maths would be beyond horrific) that such an event wouldn't occur more than once in the lifetime of several universes, but hey, these lottery tickets are free!



Links
YouTube What is Quantum Tunnelling? An excellent animated introduction.
Quantum Mechanics for Beginners A good introduction to the bizarre world of QM.








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