This article does not compute without a lot of background information. For example, someone invented an new term for quantum phase coherence which is renamed contextuality. Great, that is what we need...anopther term to describe something that we do not understand understand in the first place.
Here is a blurb from a past article that would have been helpful here:
"The term "contextuality" simply refers to the weird way in which a property of a quantum particle can depend on the context of the experiments you do to investigate it, even if there seems to be no good reason why that should be so. "It's like the colour of your socks affecting the experiment," says Joseph Emerson, an FQXi member and quantum physicist at the University of Waterloo, Ontario, who also researches this area of physics. (See "The Quantum Truth Seeker.") This doesn't hold true in the everyday macroscopic world: a given playing card in a deck is either black or red, and it stays that way regardless of whether anyone looks at it or not, or the way in which they look. This steadfastness does not always apply to quantum systems, where properties may not be set until they are observed, and when and how measurements are carried out can change the outcome of the experiment."
Yes. Ordinary classical reality does not decohere very fast and so we think of classical gravity reality as permanent. A playing card is either red or black...but that will that be true for all time. In ten years, one thousand years, or one million years, the playing card will indeed be something else. In other words, even our classical reality is subject to a very slow decoherence rate. The usually very slow classical decoherence gives us the illusion of permanence and locality.
In contrast to classical states, quantum states usually decohere very rapidly into classical states. What seems strange is that quantum states can actually remain coherent for very long times and over very long time separations. This kind of phase coherence makes no classical sense, i.e., that we can know the state of a particle across the universe just because we know the state of an entangled particle right here right now.
Any discussion about qubits that does not include decoherence rates leaves out a necessary factor for any quantum computer. Decoherence is more than just the inevitable scrambling of information. Decoherence provides the key for understanding all of our quantum reality.