I have an adage that no-one ever seems to buy, that aiming to make oneself redundant is a primary driver (for me and quite a few people I know, at least). If something takes effort to explain and sell, implement and extract value, then there is work for consultants, sure, but boy it becomes boring very fast, if that thing doesn’t get easier for people to pick-up and use. The object really is to put yourself out of a job, and move onto more interesting (rewarding) work, rather than giving the same presentations to the same conferences year after year.
I was struck by the same motive in laying quantum theory(ies) to rest in this paper by Christopher Fuchs of Bell Labs.
The issue is, when will we ever stop burdening the taxpayer with conferences devoted to the quantum foundations? The suspicion is expressed that no end will be in sight until a means is found to reduce quantum theory to two or three statements of crisp physical (rather than abstract, axiomatic) significance. In this regard, no tool appears better calibrated for a direct assault than quantum information theory. Far from a strained application of the latest fad to a time-honored problem, this method holds promise precisely because a large part – but not all – of the structure of quantum theory has always concerned information. It is just that the physics community needs reminding.
For me the quality of information is a root topic, and whilst being a David Deutsch fan, I’m not an Everettic – the multi-verse flavour of many worlds is usually a kludge IMHO.
Fuchs is the keynote speaker at Quantum Interaction 2011 in Aberdeen, 27 to 29 June.
Is it possible to imagine that any mind – even Einstein’s – could have made the leap to general relativity directly from the original, abstract structure of the Lorentz transformations? A structure that was only empirically adequate? I would say no.
The quantum system represents something real and independent of us; the quantum state represents a collection of subjective degrees of belief about something to do with that system … The structure called quantum mechanics is about the interplayof these two things – the subjective and the objective.
My emphases. Wow, that’s a scientist talking. And the obligatory apology to avoid the new-agey jibes.
I should point out, however, that in contrast to the picture of general relativity, where reintroducing the coordinate system – i.e. reintroducing the observer – changes nothing about the manifold … I do not suspect the same for the quantum world. …
Observers, scientific agents, a necessary part of reality? No.
But do they tend to change things once they are on the scene? Yes.
[space-time with and without mass present]
If quantum mechanics can tell us something deep about nature, I think it is this.
Previously, I have not emphasized so much the radical Bayesian idea that the probability one ascribes to a phenomenon amounts to nothing other than the gambling commitments one is willing to make on it. To the radical Bayesian, probabilities are subjective all the way to the bone. … Believe me … if the reader … fears that I will become a crystal-toting New Age practitioner of homeopathic medicine – I hope he will keep in mind that this attempt to be absolutely frank about the subjectivity of some of the terms in quantum theory is part of a larger programme to delimit the terms that can be interpreted as objective in a fruitful way.
And nearing conclusions:
Quantum states – whatever they be – cannot be objective entities.
A quantum state is as a state of belief about what would happen if one were to approach a standard measurement device.
Quantum entanglement is a secondary and subjective effect.
A measurement is is just an arbitrary application of Bayes’ rule – an arbitrary refinement of one’s beliefs – along with some account that measurements are invasive interventions into nature.
Subjective. Subjective! Subjective!!
It is a word that will not go away.
The last thing we need is a bloodbath of deconstruction.
At the end of the day, there had better be element in quantum theory that stands for the objective, or we might as well melt away and call the whole world a dream.
A grain of sand falls into the shell of an oyster and the result is a pearl. The oyster’s sensitivity to the touch is the source of a beautiful gem.
A’s attempt to surreptitiously come into alignment with the B’s predictability is always shunted away from its goal. This shunting of various observer’s predictability is the subtle manner in which the quantum world is sensitive to our experimental interventions. Maybe this is our crucial hint! The wedge that drives a distinction between Bayesian probability theory in general and quantum mechanics in particular is perhaps nothing more than this ‘Zing!’ of a quantum system that is manifested when an agent interacts with it.
It is this wild sensitivity to the touch that keeps our information and beliefs from ever coming into too great an alignment.
Can’t help seeing the macro-level, non-linear “game theory” view in this final statement.
BTW in a nutshell.
Measurement (interaction / participation)
disturbs information about a physical system,
NOT the real physical system itself.