A student joked that the interpretations of quantum mechanics which I tend to support are those of a party pooper. At first I didn’t like the connotation, but then I realized hey – why not? Lets turn this into a real thing.
The first thought that crossed my mind was that I’m not in any way spoiling the good party. No way! Not me. The ability to predict basically all of chemistry, the absorption and emission lines of spectroscopy, lasers, transistors, and all this good stuff – still stands. If anything, a reasonable and demystified interpretation of quantum mechanics makes the party all that much better. Heck, even quantum computers, despite the endlessly wrong descriptions that are often given to how they work, are still a possibility for arriving at the party. That was why I didn’t like the term at first.
However, why not consider what she actually meant? She meant that the party was for those who were riding on top of the successes of quantum mechanics and pushing their condescending, pseudoscientific, and just plain fraudulent ideas. What may have begun as a misguided and sure perhaps brilliant marketing scheme by Feynman has become a free-for-all for deceiving students and promoting mysticism where it doesn’t belong. If that’s what the party is about – then yeah, I like the party poopers. I’m not going to call the cops but I will point out it’s time to start cleaning up and if the freeloaders keep hanging around too long I am going to put Kenny G on the stereo at full volume to get them out.
So without further ado lets get started with the basic principles of the Party Pooper Interpretation of Quantum Mechanics
- There are always analogies with macroscopic systems to help us understand what is going on with the microscopic systems. There are macroscopic eigenvalue problems, macroscopic probability wavefunctions, and quantizations. An electron behaves in some ways like a hurricane. It has no clearly defined edge, an angular momentum, a direction of motion, and a fairly well defined center. You’re not sure if you are going to get hit by one until it happens.
- When we say a system is in a superposition of states, we mean that the system has not yet exhibited characteristics that determine which of the states it is in. Macroscopic systems can also have this behavior, it is a technique of probability to use this construction. We weigh all possibilities with their probabilities to determine the expectation value of a bet.
- Words like “particle” imply a certain context of the observer, that the observer is very far from the specific properties of the object. A planet is a good particle in a solar system, until you get close and have to start talking about the details of the geography.
- Measurements are always probabilistic, and always collapse a system in the mind of the one making the measurement. A coin is in both of your hands equally and simultaneously, for the purposes of my calculation, until I guess a hand and you show that it is empty. At that moment, the coin’s probability becomes much greater in the other hand. This doesn’t violate causality nor special relativity.
- A qubit is in both 0 and 1 state at the same time just in the same way that an ordinary bit is in both the 0 and 1 state at the same time. As soon as either one is measured, we see that it was only 0 or only 1. The difference is that in an ordinary computer or Turing machine the bits are isolated – a read head comes and reads them, and responds with electronic logic gates before looking at the next. In a quantum computer, they are not isolated – they are linked together in a very complex way such that adjusting one qubit can subtly alter many others – even before their state is read.
- The beer is in the fridge. Well, you might have to look. As soon as you open the door, the wavefunction will collapse.
- If the party is for fermions, the capacity is limited, I will check if you are on the guest list. For bosons, you’re all welcome to come. Keep on coming!