Beauty and the Biased

A big thank you to Matin Durrani for the invitation to provide my thoughts on the Strumia saga — see “The Worm That (re)Turned” and “The Natural Order of Things?” for previous posts on this topic — for this month’s issue of Physics World. PW kindly allows me to make the pdf of the Opinion piece available here at Symptoms. The original version (with hyperlinks intact) is also below.

(And while I’m at it, an even bigger thank you to Matin, Tushna, and all at PW for this immensely flattering (and entirely undeserved, given the company I’m in) accolade…

From Physics World, Dec. 2018.

A recent talk at CERN about gender in physics highlights that biases remain widespread, Philip Moriarty says we need to do more to tackle such issues head on

When Physics World asked several physicists to name their favourite books for the magazine’s 30th anniversary issue, I knew immediately what I would choose (see October pp 74-78). My “must-read” pick was Sabine Hossenfelder’s exceptionally important Lost In Math: How Beauty Leads Physics Astray, which was released earlier this year.

Hossenfelder, a physicist based at the Frankfurt Institute of Technology, is an engaging and insightful writer who is funny, self-deprecating, and certainly not afraid to give umbrage. I enjoyed the book immensely, being taken on a journey through modern theoretical physics in which Hossenfelder attempts to make sense of her profession. If there is one chapter of the book that particularly resonated with me it’s the concluding Chapter 10, “Knowledge is Power”. This is a powerful closing statement that deserves to be widely read by all scientists, but especially by that especially irksome breed of physicist who believes — when all evidence points to the contrary — that they are somehow immune to the social and cognitive biases that affect every other human.

In “Knowledge is Power”, Hossenfelder adeptly outlines the primary biases that all good scientists have striven to avoid ever since the English philosopher Francis Bacon identified his “idols of the tribe” – i.e. the tendency of human nature to prefer certain types of incorrect conclusions. Her pithy single-line summary at the start of the chapter captures the key issue: “In which I conclude the world would be a better place if everyone listened to me”.

Lost in bias

Along with my colleague Omar Almaini from the University of Nottingham, I teach a final-year module entitled “The Politics, Perception, and Philosophy of Physics”. I say teach, but in fact, most of the module consists of seminars that introduce a topic for students to then debate, discuss and argue for the remaining time. We dissect Richard Feynman’s oft-quoted definition of science: “Science is the belief in the ignorance of experts”.  Disagreeing with Feynman is never a comfortable position to adopt, but I think he does science quite a disservice here. The ignorance, and sometimes even the knowledge, of experts underpins the entire scientific effort. After all, collaboration, competition and peer review are the lifeblood of what we do. With each of these come complex social interactions and dynamics and — no matter how hard we try — bias. For this and many other reasons, Lost In Math is now firmly on the module reading list.

At a CERN workshop on high-energy theory and gender at the end of September, theoretical physicist Alessandro Strumia from the University of Pisa claimed that women with fewer citations were being hired over men with greater numbers of citations. Following the talk, Strumia faced an immediate backlash in which CERN suspended him pending an investigation, while some 4000 scientists signed a letter that called his talk “disgraceful”. Strumia’s talk was poorly researched, ideologically-driven, and an all-round embarrassingly biased tirade against women in physics. I suggest that Strumia needs to take a page — or many — out of Hossenfelder’s book. I was reminded of her final chapter time and time again when I read through Strumia’s cliché-ridden and credulous arguments, his reactionary pearl-clutching palpable from almost every slide of his presentation.

One criticism that has been levelled at Hossenfelder’s analysis is that it does not offer solutions to counter the type of biases that she argues are prevalent in the theoretical-physics community and beyond. Yet Hossenfelder does devote an appendix — admittedly rather short — to listing some pragmatic suggestions for tackling the issues discussed in the book. These include learning about, and thus tackling, social and cognitive biases.

This is all well and good, except that there are none so blind as those that will not see. The type of bias that Strumia’s presentation exemplified is deeply engrained. In my experience, his views are hardly fringe, either within or outside the physics community — one need only look to the social media furore over James Damore’s similarly pseudoscientific ‘analysis’ of gender differences in the context of his overwrought “Google Manifesto” last year. Just like Damore, Strumia is being held up by the usual suspects as the ever-so-courageous rational scientist speaking “The Truth”, when, of course, he’s entirely wedded to a glaringly obvious ideology and unscientifically cherry-picks his data accordingly. In a masterfully acerbic and exceptionally timely blog post published soon after the Strumia storm broke (“The Strumion. And On”), his fellow particle physicist Jon Butterworth (UCL) highlighted a number of the many fundamental flaws at the core of Strumia’s over-emotional polemic.   .

Returning to Hossenfelder’s closing chapter, she highlights there that the “mother of all biases” is the “bias blind spot”, or the insistence that we certainly are not biased:

“It’s the reason my colleagues only laugh when I tell them biases are a problem, and why they dismiss my ‘social arguments’, believing they are not relevant to scientific discourse,” she writes. “But the existence of those biases has been confirmed in countless studies. And there is no indication whatsoever that intelligence protects against them; research studies have found no links between cognitive ability and thinking biases.”

Strumia’s diatribe is the perfect example of this bias blind spot in action. His presentation is also a case study in confirmation bias. If only he had taken the time to read and absorb Hossenfelder’s writing, Strumia might well have saved himself the embarrassment of attempting to pass off pseudoscientific guff as credible analysis.

While the beauty of maths leads physics astray, it is ugly bias that will keep us in the dark.


When scientists help to sell pseudoscience: The many worlds of woo

…or, as Peter Coles suggested, The Empirical Strikes Back

Until a couple of weeks ago, I was blissfully unaware that there was a secret out there that had the potential to change my life forever. I could do anything, be anything, get anything I so desired… if I only knew The Secret. Despite my hitherto abject ignorance, it’s not a particularly well-kept secret: millions know about it — and its universal law of attraction guiding ‘principle’ — largely due to Oprah Winfrey’s glowing and gushing endorsement.

Nor is The Secret anything new. The film which first gave it away was released nearly a decade ago. Like the best memes, however, its rate of infection continues to grow. Googling “The Law of Attraction” gives millions upon millions of hits, and counting.

I found out about The Secret via Tim Brownson and Olivier Larvor, both mentioned in my previous post, and with whom I had a fun and expletive-fuelled discussion for their Raw Voices podcast last Friday. We chatted about the regular claim made by ‘Law of Attraction’ gurus — who make a nice little earner out of selling their ‘expertise’ — that quantum physics is at the heart of The Secret.  (I’ll add a link to the podcast when it becomes available. Edit 31/08/2015. The podcast is here.)

So what is The Secret? Well, it’s nothing more than the idea that if you think positive thoughts, good things will happen to you. The rather vile converse tenet is also part of The Secret: anything bad that happens to you is simply because you’re not thinking enough good thoughts. The law of attraction is just another way of expressing The Secret: if you think those good thoughts and click your heels together three times, you’ll attract good stuff to you. (Quite whether it’s an inverse square law has not yet been ascertained.)

Where does the quantum physics come in? I’ll let Rhonda Byrne, author of The Secret, enlighten you by way of a few quotes from her book:

The law of attraction is the law of creation. Quantum physicists tell us that the entire Universe emerged from thought.

Your thoughts determine your frequency, and your feelings tell you immediately what frequency you are on.

The law of attraction is a law of nature. It is as impartial and impersonal as the law of gravity is.

How it will happen, how the Universe will bring it to you, is not your concern or job. Allow the Universe to do it for you.

The Universe offers all things to all people through the law of attraction.

It’s easy and cathartic, of course, to rant about the anti-scientific nature of this type of delusional woo and to bemoan the extent to which our culture celebrates irrationality and “mysticism”. As Toby Young pointed out in an article celebrating the end of Oprah Winfrey’s chat show,

Above all, it is Oprah’s incontinent sentimentality that I find so objectionable, the elevation of ersatz emotion over any critical thought. For Oprah, the only test of veracity worth the name is whether something “feels” true, as though our initial emotional response to something – whether a prospective lover, a spiritual belief system or a political leader – is a more reliable guide than a careful sifting of the evidence.

This elevation of what “feels true” above cold, hard, impersonal evidence is, of course, why Oprah was such a fan of “The Secret”. Nonetheless, a central credo of Byrne’s books — and of the extremely lucrative legions of woo they have inspired — is that the “law of attraction” is grounded in science. This claim lends The Secret an air of credibility by effectively exploiting the classic argument from authority fallacy: if quantum physicists say there’s something in it, then Byrne must be onto something. (There’s a fascinating type of cognitive dissonance at play here, however, in that when scientists deign to criticise The Secret they’re of course told by Byrne’s acolytes that science doesn’t know everything).

It’s always fun for us scientists to get on our high horse and loudly berate Byrne, Deepak Chopra, Robert Lanza, and the many and varied other purveyors of woo for their lack of understanding of science, and of quantum physics in particular.

But we’re a big part of the problem.

Compare Byrne’s claim,

The law of attraction is the law of creation. Quantum physicists tell us that the entire Universe emerged from thought. 


“[T]he atoms or elementary particles themselves are not real; they form a world of potentialities or possibilities rather than one of things or facts.” Werner Heisenberg

“In the beginning there were only probabilities. The universe could only come into existence if someone observed it. It does not matter that the observers turned up several billion years later. The universe exists because we are aware of it.” Martin Rees (from The Anthropic Universe, New Scientist (August 1987))

We now know that the moon is demonstrably not there when nobody looks. N. David Mermin (The Journal of Philosophy 78, 397 (1981))

“It was not possible to formulate the laws of quantum mechanics in a fully consistent way without reference to consciousness.”  Eugene Wigner

We have reversed the usual classical notion that the independent ‘elementary parts’ of the world are the fundamental reality, and that the various systems are merely particular contingent forms and arrangements of these parts. Rather, we say that inseparable quantum interconnectedness of the whole universe is the fundamental reality…  (David Bohm, quoted in The Tao Of Physics, Fritjof Capra (1975))

Can we really blame Byrne, Chopra, et al. for promoting the idea that we’re all part of one interconnected universe, whose structure/reality we influence with our thoughts, when not only popular science books/magazines, but the scientific literature, are awash with statements like those above? After all, the preceding list of quotes is from a set of highly respected physicists who have made huge contributions to our understanding of the universe. Moreover, when we lesser scientists speak about quantum physics to the wider public(s) we’ll often quote those luminaries and talk up the more ‘fantastical’ elements of the theory.

I suspect that there are physicists who would immediately baulk at my use of “fantastical” and would point out that we live in a world that is essentially quantum. I beg to differ. The world around us is indeed the result of literally countless quantum events. But the quantum weirdness is washed out precisely because of the uncountable and uncontrollable combinations of those unthinkably large numbers of quantum events.

We live in a world of classical physics. While this, on the face of it, is a statement of the bleeding obvious, those of us involved in communicating science need to be a little more upfront about it.  Yes, of course quantum theory is the jewel in the crown of science (at least from this lowly “squalid state” physicist’s perspective), underpinning the structure and behaviour of all matter. And, yes, there are of course fascinating, unsettling (to some more than others), and complicated connections between information theory and quantum theory at the most fundamental level. For what it’s worth, I’m of the opinion that there’s a lot to be said for Anton Zeilinger‘s interpretation of the “message of the quantum“:

…the distinction between reality and our knowledge of reality, between reality and information, cannot be made. There is no way to refer to reality without using the information we have about it.

…but we have to realise that for the macroscopic systems all around us every day, there are immeasurably many ways that information can ‘leak out’. Everything around us — the walls of my office, the trees I can see through my window, the pizza I had for lunch, the nitrogen and oxygen molecules in the air I’m breathing — is an “observer”. Consciousness not required. That long-suffering and infuriating feline is observed long before the box is opened.

Debates regarding the ontological vs epistemological aspects of the wavefunction (and its associated ‘collapse’, if you subscribe to the Copenhagen interpretation) continue to rage. This, by Matt Leifer, is by far the best review I’ve read on the question of the ontic vs epistemic nature of the wavefunction. I enthusiastically recommend Leifer’s paper for key insights into the “state of the nation” when it comes to the fundamental interpretations of quantum mechanics. (His blog posts are also well worth reading).

John Stewart Bell, whose contributions to quantum theory have been lauded — although not by some — as “the most profound discovery in science“, was rather scathing about what he called the FAPP (“for all practical purposes”) principle. This was, in effect, his equivalent of the “shut up and calculate” dictum (traditionally attributed to Feynman but possibly (probably?) originally due to David Mermin) . He made arguments both against FAPP and in support of treating all of the universe on an equal quantum mechanical footing in his classic Against Measurement article back in 1990:

Is it not good to know what follows from what, even if it is not really necessary FAPP?

In the beginning natural philosophers tried to understand the world around them. Trying to do that they hit upon the great idea of contriving artificially simple situations in which the number of factors involved is reduced to a minimum. Divide and conquer. Experimental science was born. But experiment is a tool. The aim remains: to understand the world. To restrict quantum mechanics to be exclusively about piddling laboratory operations is to betray the great enterprise. A serious formulation will not exclude the big world outside the laboratory.

But there’s no getting away from the fact that “the big world outside the laboratorydoes behave very differently from those “piddling laboratory operations” designed to test the fundamentals of quantum mechanics. In the headlong rush of excitement brought about by the inherent weirdness/counter-intuitiveness of quantum mechanics we too often gloss over this when explaining quantum mechanics to a non-scientific audience (or to a scientific audience unfamiliar with the minutiae of quantum physics). Put bluntly, it doesn’t matter how many times you attempt to repeat the double slit experiment at a macroscopic scale by firing marbles at a couple of slots cut in a piece of cardboard — you’re not going to see the appearance of an interference pattern.

While physicists and philosophers continue to debate the reasons for this lack of “quantumness” on macroscopic scales — including the extent to which decoherence explains the loss of the interference pattern — the empirical observation is simply this: coherent interference, the bedrock of quantum weirdness, is not realised for macroscopic objects in the everyday world.

Zeilinger, Arndt and co-workers (including, at one time, my colleague now here at Nottingham, Lucia Hackermüller) have carried out elegant — or what are perhaps better described as heroic — experiments with ever-larger quantum objects to show that interference effects are possible even for molecules as large as 6 nm in size with a mass of 6910 atomic mass units. In a particularly impressive piece of work whose results were published in 2012, Juffman and co-workers imaged the molecule-by-molecule build up of a quantum interference pattern for two types of phthalocyanine molecule, namely PcH2 (C32H18N8, 58 atoms with a mass of 514 amu), and its larger fluorinated counterpart F24PcH2 (C48H26F24N8O8,F24PcH2, 114 atoms, mass 1298 amu). Here’s a video of the formation of a molecular interference pattern a molecule at a time:

…and here’s a comparison of the interference patterns formed by (a) the smaller and (b) larger molecules.


Despite the remarkable level of experimental control achieved by Juffman et al., the visibility of the interference pattern for the larger molecule is much weaker due to the contribution of an incoherent background arising from the size of the source of the molecules and the molecular velocity distribution. 1298 amu is about 22 orders of magnitude smaller than the mass of a marble. (You can add another three orders of magnitude for the mass of the average human being). When decoherence is an issue for particles which are 1298 amu in size and contained in an exceptionally well-controlled experimental environment, it’s clear just why coherent quantum interference isn’t a feature of the macroscopic world.

This simple absence of quantum interference for everyday objects is enough, by itself, to entirely debunk the claims of Byrne, Chopra, Lanza and other woo-meisters. When was the last time they diffracted when walking through a doorway?

It’s no Secret: we live in a classical world.

Before I stumble to the end of this long-winded post, I want to tackle — as briefly as possible — two other frustrating aspects of quantum woo that, again, we physicists have perhaps not always done enough to counter. The first is the idea of the “holistic” interconnected universe, as described by Bohm in that quote above: “…inseparable quantum interconnectedness of the whole universe is the fundamental reality…”.

In one technical, and entirely unmeasurable, sense, as you read this your electrons are indeed entangled with mine. And they’re entangled with those of every animal, mineral, and vegetable on the planet. And with those of any small, blue, furry alien species yet to be discovered. As I’ve discussed in a previous post, this coupling arises in quantum theory because, in essence, there’s no such thing as complete, perfect confinement of an electron (or any other particle).

But this predicted coupling between electrons in two human beings in the same room, let alone on different sides of the globe, is so mind-bogglingly tiny — smaller than the smallest thing ever, and then some — that it has zero influence on anything we measure or could ever hope to measure. FAPP, there is no coupling at all (and that’s why we can treat the Pauli exclusion principle for electrons in a particular atom without ever having to worry about all the other atoms in the universe).

Here I disagree fundamentally with Bell in that I’m soundly of the opinion that the distinction between “practice” and “principle” is absolutely key to the science we can do and, in particular, how we explain that science to various audiences. It therefore impinges directly on the questions about the nature of reality we can address. That’s because I’m a cynical old experimentalist who has too often seen beautiful theoretical predictions (from that most powerful of tools in the condensed matter theorist’s toolbox, density functional theory) shot down in flames because of an ugly experimental result. Thus begins a process of rehabilitating and tweaking the theoretical methods: “Oh, we just need to use a different functional…The exchange-correlation term isn’t quite cutting it…The dispersion interactions aren’t accounted for…There’s an issue due to basis set superposition we need to address…“.

That type of feedback between experimental measurement (or observation) and theoretical calculation is absolutely central to science. I was therefore gobsmacked by claims last year that we’re supposedly entering a world of “post-empirical science“,  and was very happy to see those claims promptly and elegantly rebutted by Sabine Hossenfelder. If there’s anything that will help promote the further rise of outlandish woo, it’s a move by scientists towards the idea that claims about the nature of the universe don’t need to be supported by observation, data, or evidence; that the “internal consistency” or elegance of a theory is good enough for it to be accepted. Beauty is merely in the eye of the beholder.

If it disagrees with experiment, it’s wrong. In that simple statement is the key to science. It doesn’t make any difference how beautiful your guess is, it doesn’t matter how smart you are who made the guess, or what his name is… If it disagrees with experiment, it’s wrong. That’s all there is to it.

That was Feynman, of course, on the scientific method. Lest we forget.

Coupled with this rather hubristic notion of “post-empirical” science is the related troublesome confusion, as highlighted by Peter Coles, between the map and the territory. A mathematical model is exactly that — a model. We will further bolster the “woo age” movement if we start mistaking a mathematical model, i.e. the map, with the territory of reality. So, for example, while I can entirely appreciate just why Sean Carroll and others are rather wedded to the many-worlds interpretation (MWI) of quantum mechanics, claims that the MWI is “probably correct“, for reasons including that it has the smallest number of postulates compared to any other breed of QM, leave me cold. Why is the most accurate theory necessarily the most elegant or the most “compact” in its postulates? I seem to hear the distant sound of bongos being beaten in frustration…

Similarly, there’s an argument justifying the “reality” of the many worlds of the MWI that goes something along the lines of — if you’ll excuse the paraphrasing of Mr. Adams — “Hilbert space is big. Very big. You just won’t believe how vastly, hugely, mind-bogglingly big it is.”. But an infinite dimensional Hilbert space is a mathematical construct. And a state in that infinite dimensional Hilbert space, or, indeed, in any finite dimensional Hilbert space we might consider, is not a physical entity. It’s a model. As Eric Scerri memorably pointed out over fifteen years ago in the context of claims that electron orbitals had been experimentally observed, a state in Hilbert space is about as real as the Cartesian x,y,z axes we use to model problems in classical physics. (This is not to say that I don’t see some of the attractions of the MWI over the traditional Copenhagen approach; Carroll does an impressive job of laying out the MWI’s virtues. Nonetheless, I remain unconvinced by Carroll’s stance on the issue of testability and share Chad Orzel’s agnosticism regarding the various ontic vs epistemic interpretations of quantum mechanics.)

What really matters when it comes to stemming the steady flow of woo, however, is that none of this quantum weirdness has any influence at all on how we live our lives. When we communicate science to a diverse audience we need to spend a little less time exploiting the “Wow. Quantum. Physics.” factor — and I’m certainly hardly blameless here — and explain carefully why classical physics holds sway in the world around us.

If we don’t, we could very well be adding our own small quantum of woo to the spread of pseudoscience.