Posts Tagged ‘Realism’

QUANTUM: De Tout Pour Faire Le Monde

January 24, 2015

QUANTUM: OBVIOUS YET ALL CHANGING

Quantum Physics is so natural that it embraces the fundamental organizing principle of superior human intelligence: “Il faut de tout pour faire un monde”.

It is continually said that Quantum Physics is “weird”. Maybe it is, but much less than any alternative previously imagined, such as Classical Mechanics. Classical Mechanics rest on a handful of strict “laws”. Instead, as we will see, the Quantum rests on just one very general principle, but, from there, enables the great freedom of spaces galore.

Indeed what is the most obvious alternative, between Classical and Quantum?

True, at first sight, the world looks classical. Yet, the classical vision, that the world made of points, is very naïve.

Electrons Make Their Own Space Around The Nucleus

Electrons Make Their Own Space Around The Nucleus

An analogy helps.

One need to go back to biology. Centuries ago, it was thought that a human being originated as an “homunculus”: a human being, just much much smaller. The truth turned out to be different: instead of keeping the same system of idea, genetics and molecular biology brought in completely new systems. The older ones are still around, but they were mostly displaced, or even partly completely replaced, by new systems of ideas.

Similarly, physicists, for centuries, thought that in the physical universe, the smaller one would look, the more one would see just the same thing, space-time with points, ever smaller. Could the small be like the big, just smaller and smaller?

That would have meant that there was no different explanation to the inner working of what we see… From what we see. Looking at the very small would not have provided with a different system of ideas (although looking at a smaller scale had provided with new systems in biology).

Such was the Classical Prejudice: smaller was not supposed to be any different. Yet plenty of phenomena were found that the “small is not any different” view could not explain.

And indeed, nature is not like that. First, Planck found that supposing that light energy was emitted in lumps explained two mysteries (Lord Kevin had called them “dark clouds”). Einstein then explained the photoelectric effect by the reception of light in lumps too.

Jumping further than he should have, he then proposed the hypothesis of “lichtquanten”.

Where did those Planck-Einstein lumps, those “Quanten” come from?

The most natural explanation was waves. In a constrained space, stable waves happen only at some frequencies. This explanation appeared with Bohr, in the constrained spaces around atoms, and was generalized with De Broglie’s Wave Principle”:

“To any particle is associated a guiding wave”.

At that point, Quantum Physics was essentially done: if it was all about waves, the uncertainty principle was obvious.

Next one had to define what a “wave” could be. Well, something given by a wave equation (what else?). Notice the difficulty: wherever we look, it’s not obvious what a wave is (just rolling out the second order partial differential equation used for bow strings will not do; although that works for that, does not make it a general principle, as we are going to see!)

The De Broglie(-“Schrödinger”) equation was just the most obvious candidate, but others appeared, like the relativistic Klein-Gordon.

Dirac rolled out the most general, simplest wave equation, the square root of the most obvious relativistic wave. That first order Dirac equation required a new space, Spinor Space (discovered independently much earlier by the mathematician Elie Cartan in 1913). It predicted a new particle: the anti-electron.

So Quantum Physics is actually the simplest imaginable logic to organize Nature as we have observed it. It’s not “weird”, it’s enlightening.

Notice that I implicitly solved the “Measurement Problem”: the concept of wave is, well wavy, fuzzy (actually, Quantum Waves penetrate walls, to some extent). So we cannot be sure that the “wave-function” we have are really perfectly defined, as a depiction of all what “reality” is, to START WITH (actually there are non-linear, arbitrarily close approximations of the “Schrödinger” equation).

Actually the history of Quantum Physics (and QFT) is a succession of wild guesses about what the wave equations could be. A few of these guesses worked, most of them did not (in many cases because non-linear effects had been neglected, such as “Normalization”).

De Broglie’s “Guiding Wave” class of theories was rejected (erroneously, it turned out) by some arrogant mathematicians. However, very recent experiments showed that some basic Quantum behavior can be duplicated experimentally with waves in fluid mechanics.

Bohm’s approach is just the PARTICULAR case of De Broglie’s general approach; as Bohm was born in the USA, the Anglosphere refers to him, but it’s truly De Broglie who invented the whole thing.

Reintroducing particles, as Bohm does, is throwing the baby with the bath. The bath, and the baby, are made of waves. Nobody said that they have to be linear.

(David Bohm, a physics professor at Princeton, USA born, was thrown out of the USA for… thinking. He was the first one to say that his 1953 theory was just part of De Broglie’s ideas. Bohm pursued his career in Brazil, and then England. In the late 1950s, he discovered the “Bohm-Aharanov effect”, the major fact that potentials were central to Quantum Physics, the very foundation of so-called “Gauge Theories” of Quantum Field Theory. )

And the Quantum is waving out there in many ways, in many spaces, some infinite dimensional. That’s the best realism we have.

It’s more fundamental than space and time, as we classically know them.

The classic picture of the universe was naïve. The Quantum vision changes everything. It provides us with enormously powerful new systems of ideas. It is intrinsically not just multidimensional, but, one could say, multiversal.

Common French wisdom has long proclaimed that :”Il faut de tout pour faire un monde” (One needs everything to make a world”). Philosophical systems embracing this principle are the most opposed to intellectual fascism. Intellectual fascism is the organization of one’s view of reality around a handful of axioms: religious fanaticism for a superstition is the archetype example.

Societies where Il faut de tout pour faire un monde are the most inclusive, and those were the open market of ideas can produce. They allow to make better ideas blossom, and bad ideas fade away.

It is comforting to know that Physics, deep down inside, works just the same.

To each context, its universe, yet, out of many, just one. It takes everything, including all sorts of spaces, to make a world. This is what the Quantum proudly proclaims.

Patrice Ayme’

QUANTUM WAVE

April 5, 2014

REAL WAVE, NOT BORN KNOWLEDGE WAVE.

Abstract: Quantum Waves are real. Because the alternatives are unreal. On the way I make a drastic epistemological critique of the Copenhagen Interpretation of Quantum Mechanics (“CI”), and its modern aspect, QBism. (For a general introduction, one can consult Nature’s March 26 2014 lead editorial: ”Be here now.” http://www.nature.com/news/be-here-now-1.14922.)

***

Quantum Physics, as usually formulated, uses “observers” and “measurements”. That approach was the invention of Bohr and his flock. It was celebrated by giving the Nobel to Born (a friend of Einstein) for making Quantum Waves into “Probabilistic Waves”.

Quantum Interference Gives Birth To The Universe

Quantum Interference Gives Birth To The Universe

As Nature’s “Be here now” puts it: “Bohr and Einstein argued about whether quantum mechanics allowed any room for the idea of realism — of an objective world that exists independently from our efforts to observe and measure it. Bohr insisted that physics was concerned with what we can know, and was silent on the matter of ‘how things really are’. He, Born and Heisenberg made claims about quantum theory’s challenge to causality and determinism that today look like a bit of an intellectual stretch.”

QBism (for Quantum Bayesian), Nature magazine sings the praises of, brings nothing new to CI. Bayesian probabilities (developed mostly by Laplace!) modify the ingredients of a probability computation to get a better fit to what’s observed.

Far from being sophisticated, I would argue that the probabilistic approach to Quantum Physics, although effective, is primitive. It is what I will call, a typical first order theory of reality.

Indeed thinking from “measurements” and “observers” is exactly the way a scary smart prehistoric man who knew nothing about a subject would proceed. As he would try to be as objective as possible. And make no mistake: today’s civilization rests on countless scary smart prehistoric men, some living hundreds of thousands years ago, and maybe more.

Confronted to the unknown phenomenon, the first thing prehistoric man will notice is that situation depends upon observer and measurement, causality and determinism are not in evidence. In other words, scary smart prehistoric man would be baffled, just the way Niels Bohr and his followers (Heisenberg, Born, etc.) were baffled.

However scary smart prehistoric man did not just stay baffled, as most physicists have resigned themselves to be. Instead scary smart prehistoric men built up meta-theories, that is all encompassing brain networks that made a given phenomenon into one. (It could be a theory of Tarpan Horse hunting, or of spring floods, bad weather incoming, or the local volcano.)

The probabilistic approach, “just shut up and calculate”, CI, is only a first approach. Real science substitute concepts with a life of their own to raw data. (That life is the appropriate brain machinery set-up to organize the data; that’s what causality is.)

Even human beings (“savants”) who are natural born computers, those who can tell you instantaneously what day of the week was February 17, 1924, adorn numbers with smells, texture, colors and personalities. Numbers become personalities in a landscape.

General philosophical metaprinciple out of that? Acquiring dimensionality is acquiring reality.

(This advanced remark is an allusion to the fact full Quantum wavefunctions can be arbitrarily high dimensional, and that has nothing to do with String Theory’s pitiful 11 dimensions. Ironically, that has been the main objection against the Pilot Wave Theories.)

For example, take the Moon. Try to be objective, while playing prehistoric man. What do you observe about the Moon as Homo Erectus? (Or equivalently, Arab in the desert, 20 centuries ago.)

The Moon? A white disk, sometimes a crescent, when most of the disk is obscured. If one wants to be objective, as a Prehistoric Man, nothing more. No proof, whatsoever, for a Prehistoric Man, that the Moon is a physical object. You can’t go there, you don’t have a rocket, and you cannot see mountains on the Moon, and their shadows, you don’t have the eyes of an eagle.

So, all right, for prehistoric man, the Moon is this whitish crescent-disk, and all you can do is measurements with what you have, the appearance of the thing.

One can measure the monthly appearances of the Moon by comparing it to the Solar Year, seasons, what not. Notice things come back in cycles, but not quite.

Maybe the Moon is the language of the gods, trying to talk to us? That was the interpretation made in Antique Mecca (with its 360 gods, but with the Moon dominating). So then, obviously the Moon was a message from God, observed the Muslims, and they believe in that to this day.

This is what Bohr’s CI and his modern imitators, the QBists, achieved. They have numbers, don’t understand where they come from, and made a cult around them.

When they claimed that one could not go any further (as Von Neumann stupidly claimed to have proven), deeper thinkers smirk.

The correct scientific approach is to go beyond numbers (this, by the way, is what inflationistas have done, with their Cosmic Inflation theory; and now everybody is excited about them). Sit down, and ponder: what could the Moon be? Could it be a real object?

What’s a real object? Answer: something endowed with more than the first set of numbers we got to know about it.

Of course, the first time scary smart prehistoric man comes across a situation he did not understand, but a situation that seems to reproduce itself, again and again, he set-up an experiment, hopefully a simplified version of what he observed. OK, so a horse fell from the cliff. Excellent meat for all for a full moon. Horse flees from man, so maybe man can make many horses fall off cliff, as needed.

Arrogant twerps who believe that modern man, preferably talking the Anglo-Normand dialect, invented the experimental method, know nothing of man.

Ever since man is man, man has found out about reality with experiments to observe how nature works. Quantum Physics is not any different.

Yes, the experiments depend upon the observer. So what? It dos not mean that all that could be observed has to be experienced. Quantum Interference is everywhere, it’s the essence of creation, and men observe it on a countable set, of measure zero.

Primitive Men Believe The Universe IS All About Themselves

Primitive Men Believe The Universe IS All About Themselves

Quantum Interference Does Not Depend Upon Man

Quantum Interference Does Not Depend Upon Man

The reality the experiments are after do not depend upon the observer. That Bohr and company could not figure it out, and, instead, started to dissect and not dissect the same cat, is a monument to the frailty of human intelligence.

John Bell (inventor of the Bell Inequalities to help check that Quantum Physics is non local) was ironical about this subject. He said:“What exactly qualifies some observer to play the role of ‘measurer’? Was the wavefunction of the world waiting to jump for thousands of millions of years until a single-celled living creature appeared? Or did it have to wait a little longer for some better qualified system… with a PhD?”

Or, even better, a Nobel prize?

Of course not. (Unfortunately, Bell, the head theorist at CERN, was felled by a heart attack at the age of 62, before he could debunk more of the orthodoxy.) As I said above, believing that what we observe depends upon the observer is the most primitive objective approach. In first approach to knowledge, it’s objective to admit one’s subjectivity.

Can the “wave function” in Quantum Physics be a real object? Of course yes. Go back to the Two Slit Experiment. (Feynman correctly pointed out that the entire mystery of Quantum Physics was within the 2-slit.)

All the appearance of what we observe, when conducting a 2-slit experiment, for example between our eyelashes, observing the pretty color patterns, is that wave interference is causing the apparition of photon(s) of light in some places (where the waves interfere positively) and not in others (where waves interfere destructively).

Those waves, between our eyelashes are as real as waves in a port, no matter what a thousand Nobel laureates in physics may want to bleat about. (Lay on your back in the sun, and look through your eyelashes as you close them: this is my portable version of the 2-slit experiment.)

So what are these waves?

Above I shot down the subjective-knowledge theory of Bohr-Born-QBism. They reason from the first appearance, and forgot that experiments require, they always did, a carefully contrived measurement process, and an observer. They went prehistoric, and don’t know about it.

What’s left to understand Quantum Physics? Only two classes of theories are left.

One of them is the maniacal “Multiverse” “theory”. That insanity claims that any fundamental process generates as many universes as there are possibilities for it to evolve into. It’s an attempt to “save determinism”.

Unfortunately, the madness is infecting physics; just when we thought physics was ruled with not too smart a theory, an insane one comes to dominate. (The Multiverse was invented partly because of confusion about Schrodinger cats, as I hinted above: lack of philosophical sophistication killed the cats.)

What are we left with? De Broglie’s Pilot Wave theories. (In Anglo-Saxonia, this is known as “De Broglie-Bohm” theory, because that makes the Anglo-Saxon equal to the French, but, truly, De Broglie invented it all by himself.)

My own theory is a sci-fi version of the Pilot-Double Solution theory. It predicts Dark Matter readily (as very low mass, very weakly interacting particles, so it definitively makes falsifiable predictions).

Some will say that I am absurd, and, instead, should learn the “Standard Model” (SM) of particle physics. SM and Quantum Theory are the most successful physical theories ever, with incomparable precision.

Yet, that precision is an illusion. Theories explaining everything with 100% precision have existed in the last 25 centuries, at least (say the geocentric theory, viewed as correct, and unique, from Archimedes to Buridan, that is for 16 centuries). OK, some of those champions of the past turned out to be wrong (outside of the realm in which they had been initially checked). What’s the difference this time?

The difference, this time, is that we know that the Standard Model is wrong (Whereas the Greeks, 18 centuries ago thought the geocentric system was 100% right). Why? It explains at most 4% of the matter-energy out there (and even then with three dozens fundamental parameters!). At least my inchoate theory explains readily 30% of what’s out there in the Cosmos.

Anyway, there is no much choice for the foundations of Quantum Physics. It’s either the Schrodinger cats, simultaneously skinned and not skinned, or its deranged contradictor, the Multiverse shall rule over the mental asylum… Or the Pilot Wave theories will finally emerge.

This ship needs a pilot, to steer among the waves. As we will see in the future, this has tremendous consequences, be it only for the theory of “The Now”, as Einstein called it (and for which he had nothing to propose, although he was very worried by it, as Nature points out in “Be here now“).

Let’s conclude with a piece of ancient hanse wisdom, as it used to be written:

FLVCTVAT NEC MERGITVR (It Fluctuates, Never Sinks; Paris’ 2,000 years old motto.)

Patrice Aymé