While I would concede the point concerning "concepts", I always thought the explanation was that light was a particle that traversed space-time in the form of a wave.
Am I incorrect in this assumption? ( All these years? )
Which is just playing with words. A "particle" that can travel in the "form of a wave" is not, after all, a particle. It is something else entirely.
That's not exactly correct. The sad fact is that what we can know about subatomic particles is very dependant on the questions we are asking. When we look for wavelike behavior (wavelength, interference patterns), we will see it. When we look for particle behaviors (photons, particle interactions), we will see it. There is NO good definition of a subatomic particle like the one you posted, because what it is changes depending on the questions we ask.
Take an electron, for example. If you fire an electron or other negatively charged particle at a hydrogen atom, it will bounce away from a spot we might say is where the electron in the atom is orbiting. But why is the electron orbiting there instead of lower/closer to the nucleus? Because its wavelength is such that it cannot fit perfectly within a circle of smaller radius (ie. it can't orbit any closer). So is it a particle or a wave?
Concerning wave/particle duality, I thought you might find this tidbit interesting :
The formation of an interference pattern when a beam of particles passes through a double slit is the classic signature of the wave-particle duality of quantum particles. Wave-particle duality has been observed with electrons, atoms and small molecules. Now Markus Arndt, Anton Zeilinger and co-workers at the University of Vienna in Austria have observed wave-like behaviour in a beam of carbon-60 molecules - which are an order of magnitude larger than any other particles for which quantum interference effects have been observed…
One of the deepest mysteries of quantum mechanics is that an interference pattern is formed even if there is only one particle in the experimental set-up at any given time. The Vienna team write that "all these observations support the view that each carbon-60 molecule interferes with itself only." They also confirmed that the interactions of the molecules with their environment - such as the spontaneous emission of photons by the thermally excited molecules - could not reveal which slit they had passed through. Even the mere possibility of being able to know which slit the particle passes through would be enough to wipe out the interference pattern.