I wrote several posts about this subject but I keep seeing nonsense around… so, here, another one… What is the connection between this evening and quantum mechanics… well, after reading two very interesting papers which I strongly recommend: this http://arxiv.org/pdf/0809.0305v2.pdf and reference  therein and I am thinking about writing a paper related to the subject myself as soon as I’ll have some time, I was bombarded on my facebook page with some nonsense involving the, by now ubiquitous “many world interpretation”… Now, you know, I get goosebumps whenever I hear about this “many worlds” nonsense… and I am absolutely not in the mood to explain here, again, and again, and again why the many world interpretation is equivalent to the Copenhagen interpretation and why it means essentially nothing, apart from the pointless media hype it always tends to get… On the other side, I strongly recommend the paper by Gukov and Witten and I also recommend you to read whatever you can find about geometric quantization. Also, the Kirillov quantization, also known as “orbit quantization” is pretty important and gives quite some insight into what quantization should be and what mathematical structures you need to understand before speaking about “quantization”… Let me tell you, quantization is a tricky thing to do… it is rather obvious if you know what you have to do, and this is the case in the 0 dimensional case… not that much in the 1 dimensional case (quantum field theory) and even less in the 2 dimensional case (string theory, sigma models, etc.). The basic prescription has many “holes” in it, places where arbitrariness is pretty important and places where a choice of a specific structure may change results in a significant way.
Unfortunately, most if not all “quantum fundamentalists” or “quantum computerists” nowadays have NO CLUE about all this “stuff” and keep doing things almost blindly. We see all the time some pointless nature and science papers saying they “teleported” whatever there might be, from a photon, a boson, an atom, energy, matter, me, you, him, her from here to there, where there is the table next to mine, the lab next door, the closest island, the closest satellite, the moon, etc. but NOTHING of any fundamental relevance… If you look at quantum chemists, which are at least 50 years behind the current knowledge you will be scared about how they calculate correlation… then you go to quantum computerists and fundamentalists who are at least 70 years behind and you will see they have even less contact to path integral quantization or quantum field theory than quantum chemists… what am I saying, they still debate about BELL STATES and CAT STATES! STONE AGE RE-ENACTED!