Contrary views on Quantum Mechanics

Comrade Paddy Shannon who is not on this forum has sent in this contribution:The thing about quantum mechanics is that it works but nobody knows why it works. There have always been two conflicting views on this, which one could call the chaos and the hidden order perspectives. On the chaos side there were Heisenberg, Niels Bohr and others who contended that fundamental ‘particles’ were probably not really particles, nor waves, nor anything we can possibly imagine, and their behaviour was essentially unknowable. Even attempts to measure their position or velocity introduce an observer bias. ‘Theory’ in the prevailing Copenhagen perspective is really ‘probability’. It works because, just like with humans, you can’t predict the behaviour of individuals but you can always predict the behaviour of crowds.The other school of thought follows the tradition of classical Newtonian physics (though this goes right back to Aristotle’s dictum ‘a thing is either X or it is non-X’), and this school has never been able to accept the Copenhagen view as anything but a fudge. In this viewpoint belong Einstein (“God doesn’t play dice” etc) and Erwin Schrodinger, whose famous ‘cat’ was an attempt to illustrate the intrinsic paradox of quantum uncertainty (how can a cat be dead and not dead?). Pilot wave, hidden variables etc, are attempts to explain quantum phenomena in deterministic frameworks.Quantum mechanics is the practice of quantum physics, without the theory. You do the sums, you get the right answers, no questions asked. Quantum theory, on the other hand, is where all the bitching takes place, with jobs and promotions often depending on which view you take. For an accessible and entertaining bitching session about string theorists and why they are the spawn of Satan, check out Lee Smolin’s The Trouble with Physics.

A neat overview of quantum mechanics by the guy behind the wonderful video “Capitalism and Other Kid’s Stuff”, whose enjoyment I savoured once again.  Now, comments relating to quantum mechanics…ChaosPaddy uses the term “chaos” in its everyday sense.  He is not implying that quantum systems evolve from predictability to chaos over time, like some classical systems, e.g. the weather.  On the contrary, quantum systems hang on to their characteristic predictability over time.  They are not at all deterministically chaotic in the classical-physics sense.Physical Determinism Physics, both quantum and classical, asserts that the future state of a physical system is the deterministic result of laws of motion operating upon its current state.  A physical system evolves from its known state, through a sequence of deterministic states, into an unknown but predictable future state.If we measure the system’s known state, allow it to evolve over time, then measure its new state, and compare this measurement with our prediction, we expect agreement to within experimental error.Why then Classical Chaos? Classical chaos arises because the concrete world of classical physics is thoroughly contingent, while the laws of classical physics are thoroughly abstract.  Given enough time, a concrete classical system will evolve deterministically away from abstract predictability toward abstract unpredictability — the perceived phenomenon of chaos.Systems susceptible to evolving into chaos are those in which uncertainties in experimental measurement, no matter how tiny we make them, compound themselves “exponentially” over time to overwhelm our abstract deterministic prediction of future states, so rendering any long-term abstract prediction ultimately meaningless.Such systems are said to be critically sensitive to their initial conditions.  Quantum systems are far, far, far more puzzling than that.Nobody Knows Why It [Quantum Mechanics] Works — Yes, But That’s true, but the puzzle of why any science works applies universally to each science, each in its own way, and each way appropriate to the idiosyncratic piece of the universe that each science seeks to comprehend.This very same puzzle of why day-to-day comprehension works holds also for us in everything we do in our daily lives, and also holds for everything society does in its social being.Quantum mechanics is not classical mechanics — a subject whose historical battles are largely forgotten nowadays, but classical physics was once fiercely riven by puzzles raging over comprehension of its abstract workings, from the mysteries of the calculus to the nature of physical force and energy.Yet classical mechanics has this enormous advantage for us humans over quantum mechanics.  Half a billion years of organic evolution has endowed us humans with the survival ability to recognise and navigate our way around the classical physics world of daily experience.But organic evolution has thoughtlessly not endowed us macroscopic creatures with any special evolutionary heritage for comprehending the microscopic world, which lies beyond the daily experience of all forms of sentient organic life upon Earth.The macroscopic classical world and the microscopic quantum world are worlds that are truly, in Thomas Kuhn’s strikingly memorable term, “incommensurable”.The greatness of Bohr is that he wholeheartedly grasped quantum incommensurability from the start, and valiantly defended the strange new quantum beast in its own quantum terms against the onslaught of reacting classicists, especially Einstein, who sought to comprehend that unfamiliar quantum world in familiar [but to Bohr incommensurable] classical terms.[This message is already long.  I’ll defer my take on quantum determinism for another occasion.]Historical Determinism Marx’s guiding principle — the materialist conception of history — is deterministic:  “it is not consciousness that determines being but social being that determines consciousness”.The Socialist Party’s Declaration of Principles and the rationale behind its Object only make sense in Marx’s deterministic terms.If our Object does not deterministically guarantee the viability of world socialism — if common ownership and democratic control do not deterministically ground the day-to-day reproducibility of world socialism as a viable social system — then the Socialist Party Object is not worth our defending, and the Socialist Party and world socialism, as we conceive them, have no deterministic right to exist at all.Historical determinism is the beating heart of the Socialist Party’s case for world socialism.  It cannot be side-stepped.  The nature of world socialism’s beating heart must be comprehended by all and, for socialism to succeed, must be ruthlessly defended from the standpoint of unfamiliar socialism against the incommensurable standpoint of familiar capitalism.Voluntarism, or the attempt to sidestep determinism, is merely the ignorance of determinism.  Freedom is the recognition of determinism.

Everybody learns, and communicates, quantum mechanics with the Copenhagen interpretation.The Copenhagen interpretation, despite everything, is more than just an ideology, having won its prominent position by holding its own against reasoned opposition. I, however, have not expressed my own view, which hardly matters in the complex scheme of things relating to quantum mechanical interpretation, for the evolutionary reasons I outlined above.

So far in our discussion, I haven't adopted any position.  But to satisfy your request — the Copenhagen interpretation.

LBird,It is a good thing that Historical Materialism is determinisic. It means human agents can study, analyse, understand and ultimately control the laws that govern social change. Determism is not fatalism, it does not remove the human mind from social change.    

Guilty as ChargedLBird is mortified by reports of a litany of sins committed by quantum mechanics.“M’lud, I recount them, seriatim — violation of classical determinism [Bohr, Heisenberg]; violation of classical logic [Von Neumann]; violation of classical probability [Bell]; violation of classical information [qubit, ebit], violation of classical computing.  Need I proceed?”LBird, with his immodest penchant for pronouncing prior judgement on cases he confesses total ignorance of, has the supreme advantage over scientists of comprehending their scientific method better than they do [sic].On his dualistic idealist–materialist theory [sic], which he tells us conforms to the so-called “critical realism” of soviet historian, and Club of Rome pontificator, Adam Schaff — nature has nothing of importance to tell scientists [sic], while they have everything of importance to tell nature [sic].Consequently, those disgusting quantum scientists deserve to find themselves in a theoretical mess of their own making, because they are all misguided bourgeois scientists [sic] who insist on conceiving nature as fixed for all time [sic] — except, LBird, that quantum scientists are the very last folks that anyone except LBird could ever level this bogus charge at.These reprehensible bourgeois scientists [unlike LBird’s conceived proletarian scientists] will simply throw away their damaged theories when wounded by experimental disagreement [sic] instead of nurturing them, as a kind LBird proletarian would nurture his wounded dog — except that LBird is scarcely in a position to appreciate that each and every owner of the myriad wounded interpretations of quantum mechanics is playing out a long-term veterinary waiting game working on cures for their wounded pet interpretations.Philosophically, these shallow scientific thinkers are, for LBird, all positivists [sic] who delude themselves that objects are exactly as they seem to be [sic].  Who, but LBird, could seriously level such a stupid charge against a quantum scientist who cannot see, but must infer, the transient “objects” under investigation.Socially, these political scientific scoundrels represent for LBird, one of the twin detestable bulwarks of capitalism, namely science [sic], the other being the market [sic].  We should let the master of true scientific methodology explain such alarmism.Copenhagen InterpretationLBird’s knee-jerk reaction to his confrontation with quantum hearsay is to assume that all tacit scientific agreement over the vague-at-the-edges Copenhagen interpretation [which is a growing beast that is swallowing decoherence] is solely the result of machinations by a scientific cabal.Paddy has described the quantum interpretive situation perfectly.  My own take is that some, or possibly a great deal, of the difficulty in interpreting quantum mechanics arises out of its conceptual incommensurability with our evolutionary concrete conceptual equipment.Put it this way.  We are constitutionally incapable of conceiving in any other dimension than in our concrete three dimensions.  That was essential for our survival in a three-dimensional macroscopic world.Even when we imagine that we are conceiving in only one or two dimensions [as say when we follow the extraordinary Ancient Greek geometer Euclid], we are still actually “conceiving” those lower dimensions concretely with our three-dimensional mental baggage.  That same baggage is also exactly what we bring to our imaginative “conceptions” of the fourth [and higher] dimensions.The fact remains that we are constitutionally incapable of concretely “conceiving” other dimensions in the same visceral way we apprehend three dimensions.Well, similarly, in our concrete macroscopic world, we can quite easily grasp the concept of a spinning top.  We’ve seen, grasped and played with them.But in the incommensurable microscopic world of quantum mechanics, we cannot adequately grasp the concept of an electron’s spin in that same concrete visceral way.We can imagine an electron’s spin [in a similar way to imagining a four-dimensional object] by referring it back to what we viscerally and objectively know in our macroscopic world.  But we would be quite wrong!Now the electron spin constitutes the very simplest of all quantum systems to investigate.  It only has two measurable states — it always measures up or down [or + and –, or binary on or off, except that it turns out to be binary in a different sense of bits, namely peculiar quantum bits or qubits].A two-state system should be a breeze by comparison with classical mechanics.  But it is riddled with most of the quantum puzzles, so that up and down are not necessarily up and down even though they measure as such, but that truly amazing [dialectical] story should be told another time.DeterminismNobody is really considering giving up determinism.  As I argued in http://www.worldsocialism.org/spgb/forum/general-discussion/whats-so-special-about-base–superstructure-determinism [What’s So Special About Base–Superstructure Determinism] all science that aims to be predictive is deterministic.  To follow up on that theme is for another time.But LBird should be cautious about taking sides in debates in which each side makes its own claims about fundamental reality.  If the Bohmian interpretation makes serious headway folks will drop the Copenhagen interpretation like a ton of bricks.  Meanwhile the lame theoretical dogs continue to hop along on three legs, viable enough for getting around but not whole, awaiting a cure.