THE QUANTUM REALITY PROBLEM
Physicists now possess a perfect theory of matter — quantum theory—that is correct whenever it has been tested. Quantum theory has spawned new concepts and new technology that allow us to create and measure lots of subtle phenomena that we never knew existed— “squeezed vacuum” is one of my favorites.
But in spite of quantum theory's enormous range (from quarks to quasars) and its many successful experiments, we do not yet possess a reasonable quantum reality— a simple story about how the world actually works that we can tell to our children.
Quantum mechanics represents the world as a wave (the wavefunction) before you measure it and a particle when you measure it. A measuring device is said to "collapse the wavefunction”, instantly changing big wave into tiny particle.
Two problems with this picture: physicists don’t
know how to characterize the unmeasured wavefunction: is it a
real physical wave or some less-real wave of
possibility? This roadblock to quantum reality is called "the quantum interpretation question"
Additionally physicists do not know how to characterize a measuring device: what qualities must such a this device possess that gives it the power to turn spread-out possibility into local actuality? This quantum reaity mystery is called "the quantum measurement problem"
Our ability to tell a simple story about how this solid material world comes into existence is severely hampered by the fact that a wave whose nature we do not completely understand is changed by a process which we also do not understand into the ordinary bits and pieces, lights, colors and shadows of the familiar material world that surrounds and composes us.
Quantum theory was invented by Schrődinger and Heisenberg little more than 100 years ago but, a century later, the problem of quantum reality stubbornly remains unsolved. I wrote a book about it “Quantum Reality:Beyond the New Physics”.
THE HARD PROBLEM OF MATERIALISM
Nick Herbert noticed this first, a few days after his 90th birthday.
