Seven common myths about quantum physics

Seven common myths about quantum physics
Embedded with Physicists. Credit: Héloïse Chochois

I have been popularising quantum physics, my area of research, for many years now. The general public finds the topic fascinating and covers of books and magazines often draw on its mystery. A number of misconceptions have arisen in this area of physics and my purpose here is to look at the facts to debunk seven of these myths.

Don't worry, you don't need to know much about to read this article. I will mostly be explaining what quantum isn't, rather than what it is…

1. "Quantum physics is all about uncertainty"

Wrong! Quantum physics is probably the most precise scientific discipline ever devised by humankind. It can predict certain properties with extreme accuracy, to 10 decimal places, which later experiments confirm exactly.

This myth originated partly in Werner Heisenberg's "uncertainty principle". He showed that there is a limit to how accurately two quantities – for instance a particle's speed and its position – can be measured simultaneously. When quantum physics is used to calculate other quantities, such as the energy, or the magnetic property of atoms, it is astounding in its precision.

2. "Quantum physics can't be visualised."

Quantum physics describes objects that are often "strange" and difficult to put into pictures: wave functions, superimposed states, probability amplitude, complex numbers to name but a few. People often say that they can only be understood with mathematical equations and symbols. And yet we physicists are always making representations of it when we teach and popularise it. We use graphs, drawings, metaphors, projections and many other devices. Which is just as well, because students and even veteran quantum physicists like us need a mental image of the objects being manipulated. The contentious part is the accuracy of these images, as it is difficult to represent a quantum object accurately.

Seven common myths about quantum physics
Heisenberg’s ‘uncertainty principle’. Credit: Margaux Khalil and Janet Rafner, Author provided

Working together with designers, illustrators and video makers, the Physics Reimagined research team seeks to "draw" quantum physics in all its forms: folding activities, graphic novels, sculptures, 3-D animations, and on and on.

3. "Even scientists don't really understand quantum physics"

One of the leading lights in the field, Richard Feynman himself said: "I think I can safely say that nobody understands quantum mechanics." But he then immediately added: "I am going to tell you what nature behaves like." Niels Bohr, one of the founding fathers of the discipline, gives a good summary: "Those who are not shocked when they first come across cannot possibly have understood it."

Physicists do understand what they're doing when they're manipulating the quantum formalism. They just need to adapt their intuitions to this new field and its inherent paradoxes.

4. "A few brilliant theorists came up with the entire concept of quantum physics"

Seven common myths about quantum physics
Design makes it possible to imagine what quantum particles could be. Credit: Paul Morin et al., Author provided

The entire history of quantum physics shows the exact opposite: at the very beginning, threw up unexpected results, such as the photoelectric effect, black-body radiation, the light emission spectrum of atoms. Only later did brilliant theorists enter the scene, when Albert Einstein, Max Planck, Niels Bohr and others tried to provide explanations.

Further fundamental experiments followed, including electrons that bounced weirdly off nickel, silver atoms strangely deviated by a magnetic field, a perfectly conducting metal at low temperatures and so on. Theories and concepts then emerged once again: duality, spin or superconductivity were introduced. The highly productive "back and forth" exchanges between theory and practice are what physics is built on. Experiments generally come first, except in very few cases.

5. "Einstein was quantum physics' worst enemy"

Poor old Albert Einstein is often depicted as having been a virulent opponent of quantum physics, probably because of his famous quote, "God does not play dice with the universe." Yet he wasn't against it and what's more, he created it! In 1905 Einstein wrote his foundational article, "On a Heuristic Viewpoint Concerning the Production and Transformation of Light", based on the work of Max Planck. In it, he proposed that light was made of small, individual and quantified bodies, called photons. This is what won him the Nobel Prize, in fact, not his work on the theory of relativity.

Einstein probably earned that reputation because of his discussions with Niels Bohr, especially on the idea of interpretation and quantum reality, as he didn't accept the concept of nonlocality. Later, experiments on entanglement and violation of Bell's theorem proved him wrong and showed the absence of hidden variables. Einstein fully appreciated the relevance of quantum physics, he just had a few problems with some of its implications, especially as regards locality.

Seven common myths about quantum physics
Lasers, maglev trains and MRI are just a few of the applications of quantum physics. Credit: Marine Joumard, Flammarion, Author provided

6. "Quantum physics has no practical use"

Quantum physics is probably the most useful discipline in modern physics: once physicists understood how light, atoms and electrons worked, they were able to manipulate them. Lasers, MRI in hospitals, LEDs, flash memory, hard disks – and above all else, the transistor and electronics – all of these technologies were invented by quantum physicists.

7. "Quantum physics might explain certain alternative therapies and other mysteries"

Many people who believe in paranormal phenomena and in certain "therapies" claim to be inspired by quantum physics. Indian-American Deepak Chopra is one of the most famous proponents of this approach. He has developed a kind of quantum mysticism in which a pseudo-New Age spirituality finds its credentials in scientific jargon such as "human quantum-body essence", "localised field of energy and information with cybernetic feedback loops", and "harmonisation of the quantum mechanical body". He then purports to establish quantum relationships between mind, consciousness, matter and the universe. "Quantum therapies" also offer care protocols based on the body seen as "a vibration and energy field", host to "vibrating states" and "bioresonances".

This is dishonest on two counts. The first trick consists in using scientific terms to mystify quantum physics, when there is in fact no mystery. Lab experiments and daily living have shown its validity. On the other hand, none of the phenomena described by these therapies or beliefs have any scientific basis. Above all, words denote very precise meanings in quantum physics and they are entirely misused in these pseudo-sciences.

Seven common myths about quantum physics
An equation that raises questions – but also provides answers. Credit: Chloé Passavant et al., Author provided

More cheating can be found when quantum properties are extrapolated to a human scale. To be absolutely clear, quantum properties such as superposition of states or quantisation don't apply in the living world on a human scale. 2012 Nobel Prize–winner Serge Haroche proved this with his experiments. When an object interacts too much with its environment and becomes too large, it is no longer a quantum object.

However, I wouldn't like to judge those who wish to test this approach, which belongs to the realm of belief, not science. Everyone can do as they wish, of course. I would only ask people to refrain from pretending it has any scientific basis in quantum physics. Any such claim is simply false.

That's it! I hope that I managed to debunk physics a little. In the end, it is just like any other scientific discipline.


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Apr 15, 2019
This author knows nothing about quantum physics and Einstein was a dupe...

Apr 15, 2019
This author knows nothing about quantum physics and Einstein was a dupe...


Lol. Another crank in our midst!

Apr 16, 2019
It seems to me that you go a bit too far in asserting that understanding quantum mechanics is straightforward. Your declaration that "there is no mystery" is in conflict with your characterization of "this new field and its inherent paradoxes." Just consider that the Schrodinger equation describes a wave whose squared magnitude tells you the probability to find a particle at each position. Personally I call that mysterious, though certainly not in any mystical way.

Apr 16, 2019
I live in a fairly uneducated part of the US, and have never heard any of these misconceptions. I cant even fathom how anyone would come to those conclusions, especially given the age of googling everything. It would take a matter of 5 minutes research to discover the truth. (Well I suppose that time frame is relative based on ones speed at reading)

Apr 16, 2019
Thanks to Julien Bobroff for clarifying matters.

Those who'd care to delve deeper are encouraged to have a look at JS Bell's witty and irreverent book, 'Speakable & Unspeakable in Quantum Mechanics.'

Meanwhile...

What is proved by the impossibility proofs is lack of imagination.

~Bell

Anyone dissatisfied with these ideas may feel free to assume that there are additional parameters not yet introduced into the theory which determine the individual event.

~Born

A theory that yields "maybe" as an answer should be recognized as an inaccurate theory.

~ 't Hooft

It seems clear that the present quantum mechanics is not in its final form [...] I think it very likely, or at any rate quite possible, that in the long run Einstein will turn out to be correct.

~Dirac

There is now in my opinion no entirely satisfactory interpretation of quantum mechanics.

~Weinberg

Apr 16, 2019
In the paper "Physics and reality" published in 1936 Einstein says:
"I try to demonstrate, furthermore, why in my opinion the quantum theory does not seem likely to be able to produce a usable foundation for physics: one becomes involved in contradictions if one tries to consider the theoretical quantum description as a complete description of the individual physical system or happening. On the other hand, up to the present time, the field theory is unable to give an explanation of the molecular structure of matter and of quantum phenomena. It is shown, however, that the conviction to the effect that the field theory is unable to give, by its methods, a solution of these problems rests upon prejudice." This is one of his milder quotes. I can give here many more.
You judge from this Einstein's view on Quantum Physics.

Apr 17, 2019
lol...photons as particles...breaks the law of conservation of energy.
lol...electrons....a million dollars and a prize to call it a particle.

Apr 17, 2019
In 1936 the development of Fock states and second quantization were not well understood. In addition non-locality was not well understood; JS Bell would not publish his eponymous theory until 1964. "Quantum field theory" wasn't even a thing. Einstein was that most valuable of people: an iconoclast. That doesn't mean he was right; it just means he thought deeply and made good arguments to support his position. And he certainly didn't hate QM; he damn near invented it with his paper on the photoelectric effect, the paper for which he won a Nobel Prize in Physics.

So, no, I wouldn't say Einstein was an "enemy" of quantum physics. And I certainly wouldn't try to use anything Einstein said to "disprove" QM.

Apr 17, 2019
photons as particles...breaks the law of conservation of energy.
Ummmm, how, exactly? Considering we can detect single photons with 19th century technology scintillation screens.

Apr 18, 2019
photons as particles...breaks the law of conservation of energy.
Ummmm, how, exactly? Considering we can detect single photons with 19th century technology scintillation screens.


A photon is a man made abstraction...a 2d segment of a wave on a graph. If a photon is a real physical particle, then you would need an infinite number of "photons" in order to account for every direction illuminated in a sphere expanding out from the light source. You would also need to account for a "photon's" reacceleration after leaving a medium through which it travels slower.
There are no dualities in nature. Sound waves are compression and rarefaction, and there is no such thing as a sound particle. There is also no such thing as a photon particle.

Apr 18, 2019
No, a photon is an impact on a scintillation screen. Like, you know, one of those experiment thingies that provides data.

And you are also wrong about the sound particles; they're called phonons.

Quick tip: probably best not to bloviate about physics on the physics site if you don't know any physics. I sense a block in your immediate future. From, you know, the quantum resonances and stuff.

Apr 18, 2019
And you didn't say why photons = infinity. You merely did some handwaving that had nothing to do with it and then made the same assertion again.

The average IQ is 100. Pitiful.

Apr 18, 2019
Also noted:
There are no dualities in nature. Sound waves are compression and rarefaction
Duhhhh ummmm. And compression and rarefaction isn't a duality? What's this, an extreme comedy sketch?

Apr 18, 2019
Also noted:
There are no dualities in nature. Sound waves are compression and rarefaction
Duhhhh ummmm. And compression and rarefaction isn't a duality? What's this, an extreme comedy sketch?


There are no dualities in nature.
Phonons are not real particles. Sound is a wave not a wave-particle duality. resonances are of the medium. Phonons are still not real particles even in a resonating crystal medium.

Enough with the insulting please.

Apr 18, 2019
There are no dualities in nature.
What about compression and rarefaction?

Maybe you forgot.

Apr 18, 2019
There are no dualities in nature.
What about compression and rarefaction?

Maybe you forgot.

At the same time?

Apr 18, 2019
In the same wave. Which means, yes, at the same time, compression over here and rarefaction over there, at the same time.

Not just real clear on what a "duality" is, nor how sound works, are you?

Apr 18, 2019
I don't think that anything can be two different things at the same time.

Apr 18, 2019
Block engaged. I don't bother with trolls who use the argument from ignorance. It's dishonest and I only bother with honest people.

You cannot possibly be arguing that a sound wave, frozen in time, doesn't have alternating zones of compression and rarefaction in different places at the same time, unless you're so abysmally stupid you have no idea how sound works.

Apr 18, 2019
And you still haven't explained how photons make energy infinite. Noticed you tried to avoid that one.

Apr 18, 2019
Block engaged. I don't bother with trolls who use the argument from ignorance. It's dishonest and I only bother with honest people.

You cannot possibly be arguing that a sound wave, frozen in time, doesn't have alternating zones of compression and rarefaction in different places at the same time, unless you're so abysmally stupid you have no idea how sound works.


I never argued that.
Again, enough with the insults please. You're not insulting me. Who are you insulting?

Apr 18, 2019
And you still haven't explained how photons make energy infinite. Noticed you tried to avoid that one.


Photons don't exist.

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