Corruption of Modern Physics 19: $\Psi$ as Elephant

John Clauser will today receive the Nobel Prize in Physics from the hands of Swedish King Carl XVI Gustaf for his experimental verification of a quantum mechanical phenomenon of photon entanglement. In his Nobel Lecture (see previous post) Clauser made it perfectly clear to the perplexed audience and Prize Committee, that he finds it very difficult to understand the theory of Quantum Mechanics QM and so the theoretical significance of his own experiment. Clauser explains his difficulties to results from the presence of a theoretical Elephant in the room in the form of the wave function $\Psi$ as the holy grail of QM. 

Clauser can without loss of scientific credibility admit that he does not understand QM, because this is what most modern physicists do without blushing including Nobel Laureates, but to Clauser this seems to be a real issue, even if not so for the Nobel Committee and the King. What then is the problem with the  wave function $\Psi$? Let's see:

$\Psi (x,t)$ for an atomic system with $N$ electrons is a complex-valued function depending on a $3N$-dimensional variable $x=(x1,x2,...,xN)$ with each $xi$ representing a 3d spatial coordinate for $i=1,...,N$ and $t$ a time variable, which satisfies Schrödinger's equation. The problem with $\Psi (x,t)$ is the many dimensions of the variable $x$ formally representing $N$ different 3d coordinate systems which means that each electron has its own 3d reality while there is no common reality to all electrons. This is the Elephant Clauser is speaking of referring to the $3N$-dimensional space of the $x$-variable as configuration space without common reality, to be compared with the 3d reality of the lab space, where real physical experiments are performed. 

The Clauser Elephant represents the unclear connection between configuration space and lab space, and the Elephant does not want to leave the room.

Different techniques to deal with the Elephant have evolved over time. The most popular advocated by Bohr and Born, is to view the Elephant as only possibility thus admitting giving up reality. The other, advocated by Heisenberg and Dirac admitting nothing, is to shout "Shut Up and Calculate!", effectively resorting to mere formalism. 

So the show goes on: New Nobel Prizes to QM for discoveries nobody can understand, not even Nobel Laureates themselves. Time to listen to Clauser. And maybe take a look at Real QM. 

What is notable is that the Prize is given to experimental support of a special form of theoretical QM which cannot be understood. More precisely for giving experimental support that no other form of theory can be contemplated.