A strange "letter against statistical significance"

Anton wanted me to react to

Scientists rise up against statistical significance,

a letter written by 3 people and signed by 800 others (which may look high on the street but it's really an insignificant fraction of similar or better "scientists" in the world – surely millions). Two of the three authors have written a similar manifesto to a Nature subjournal in 2017. The signatories mostly do things like psychology, human behavior, epidemiology – mostly soft sciences. I see only 4 signatories with some "physics" on their lines and 2 of them are "biophysicists".

First, I found that text to be largely incoherent, indicating a not really penetrating thinking of the authors. There isn't any sequence of at least three sentences that I could fully subscribe to. If there is a seed of a possibly valid point, it's always conflated with some fuzzy negative attitudes to the very existence of "statistical significance" and I think that no competent scientist could agree with those assertions in their entirety.

Statistical significance may be misunderstood and used in incorrect sentences, including fallacies of frequently repeated types (I will discuss those later) and in this sense, it may be "abused", but the same is true for any other tool concept in science (and outside science). One may "abuse" the wave function, quantum gravity, a doublet, a microscope, or a cucumber, too, and this website is full of clarifications of the abuses of most of these notions. But just because people abuse these things doesn't mean that we may or we should throw the concepts (and gadgets) to the trash bin.

When it comes to the description of the "frequent abuse of statistical significance", I don't see a statistically significant positive correlation between their comments and my views – and the correlation is probably negative although I am not totally certain whether that correlation is statistically significant. ;-)

Clearly, I must start with this assertion that will also be the punch line of this blog post:

Sciences that have experimental portions and that are "hard sciences" at least to some extent simply cannot work without the concept.

A proof why it's essential: All of science is about the search for the truth. One starts with guessing a hypothesis and testing it. Whether a hypothesis succeeds in describing data has to be determined. The process is known as the hypothesis testing. The result of that test has to be quantitative. It's called the \(p\)-value (or similar, more advanced quantities). The term "statistical significance" is nothing else than a human name for a \(p\)-value or a qualitative description of whether the \(p\)-value is low enough for the hypothesis to get a passing grade. The very existence of science is really connected with the existence of the concept of the statistical significance although a few centuries ago, the significance often used to be so high or low that the concept wasn't discussed explicitly at all.

This is a mostly theoretical physics blog but there are hundreds of comments about 3-sigma this and 4-sigma that. You couldn't really express these ideas "totally differently" (except for switching from sigmas to \(p\)-values or using synonyms). We simply need to quantify how reasonable it is to interpret an experiment as an experiment in which the Standard Model has apparently failed.

You may click at Statistical significance to see that the Wikipedia provides us with a perfectly sound and comprehensible definition – which doesn't indicate that there's anything controversial about the concept itself. A statistically significant outcome is one that is unlikely to emerge according to the null hypothesis. That's why such a result makes it likely that there's something beyond the null hypothesis. This kind of the interpretation of the empirical data represents the building blocks of almost all the reasoning in quantitative enough empirical sciences!

A scalar weak gravity conjecture seems powerful

Stringy quantum gravity may be predicting an \(r=0.07\) BICEP triumph

Many topics in theoretical physics seem frustratingly understudied to me but one of those that are doing great is the Weak Gravity Conjecture (WGC) which is approaching 500 followups at the rate of almost a dozen per month. WGC hasn't ever been among the most exciting ideas in theoretical physics for me – which is why the activity hasn't been enough to compensate my frustration about the other, silenced topics – but maybe the newest paper has changed this situation, at least a little bit.



Nightingales of Madrid by Waldemar Matuška. Lidl CZ goes through the Spanish week now.

Eduardo Gonzalo and Luis E. Ibáñez (Zeman should negotiate with the Spanish king and conclude that our ň and their ñ may be considered the same letter! Well, the name should also be spelled Ibáněz then but I don't want to fix too many small mistakes made by our Spanish friends) just released:

A Strong Scalar Weak Gravity Conjecture and Some Implications

and it seems like a strong cup of tea to me, indeed. The normal WGC notices that the electron-electron electric force is some \(10^{44}\) times stronger than their attractive gravity and figures out that this is a general feature of all consistent quantum gravity (string/M/F-theory) vacua. This fact may be justified by tons of stringy examples, by the consistency arguments dealing with the stability of near-extremal black holes, by the ban on "almost global symmetries" in gravity which you get by adjusting the gauge coupling to too small values, and other arguments.

Other authors have linked the inequality to the Cosmic Censorship Conjecture by Penrose (they're almost the same thing in some contexts), to other swampland-type inequalities by Vafa, and other interesting ideas. However, for a single chosen Universe, the statement seems very weak: a couple of inequalities. The gravitational constant is smaller than the constant for this electric-like force, another electric-like force, and that's it.

A proof of highly-curved AdS/CFT, edition 2019a

Freedom of expression increasingly under attack: the Czech Wikipedia, along with the German, Danish, Slovak ones, and others, is darkened today to protest the March 26th EU-wide vote about copyright laws that would make it mandatory to preemptively search for potential copyright violations in excerpts from news. With worries like that, most sources – except for some monopolies with big legal teams – could indeed be silenced. Freedom to talk about the news is far more important than anyone's copyrights related to news.

Since the discovery of the AdS/CFT correspondence in 1997, some physicists (including me) tried to prove it. I am talking about the most famous case with the \(AdS_5\times S^5\) background of type IIB string theory that is described by the boundary CFT in \(d=4\) with the \(\NNN=4\) supersymmetry. And I am talking about some sort of a "direct proof", at least in some regime – there is a lot of circumstantial evidence that Maldacena's duality is correct, of course.



If you "thicken" propagators in a gauge theory Feynman diagram, it starts to look like a piece of a plane – which may be considered a world sheet – cut to pieces. Many things may be done with this 't Hooft picture which was the precursor of holography in the mid 1970s. Well, maybe Nathan wants to add at least one reference to a paper by 't Hooft LOL but I understand what's behind such omissions.

That duality is usually studied for a large gauge theory 't Hooft coupling where the radius of the AdS space and the five-sphere (the radii are equal) is much larger than the 10D Planck scale in the bulk quantum gravitational theory (type IIB string theory). But at some level, the correspondence should be true for a small radius as well, i.e. for the highly curved AdS space that cannot be easily described by a low-energy "classical" gravitational action.

You may Google search my blog for a proof of AdS/CFT – this topic is very old. Also because I am being acknowledged (thanks, Nathan) although I didn't give him any useful input recently, I sort of have to write about (my once co-author's and brilliant physicist's) Nathan Berkovits' new iteration of the proof:

Sketching a Proof of the Maldacena Conjecture at Small Radius

It's still a "sketch" so we don't know whether it will be treated as the "final word" on these proofs sometime in the future.

On aspects of Theranos

...and what it teaches us about bad, hyped science...

I admit that I have almost completely missed the story of Theranos and its founder, up to yesterday or so (I missed it partly because they have "only" made big claims about a limited issue, blood tests, not about a world revolution). The media were full of reviews of "The Inventor", an HBO documentary about the most famous recent Silicon Valley fraud. Interestingly enough, most of the footage in the documentary was shot for Theranos ads – and by Errol Morris whom I met in person at the 2005 SidneyFest (and a dinner in the Society of Fellows).

If you want to learn more, you need to Google search for "Theranos" or "Elizabeth Holmes". But let me start with a basic story.

Elizabeth Holmes, who is 35 now and awaiting up to 20 years in prison for massive wire fraud (she's officially broke but still lives in a hyper-luxurious apartment with various paid servants now, it turned out), has been born into an important dynasty. Her ancestors built important hospitals etc. and her father was a vice-president of a hot company – whose name happened to be Enron. I would think that even this fact should have raised some red flags – but it seems largely unknown to the public, even today.

She studied some biochemistry at Stanford but became a dropout, starting with Theranos (from Therapy+Diagnosis, originally named Real-Time Cures), a company with gadgets that make equally reliable blood tests fast and only need a droplet of your blood or so. It's not terribly important how many droplets the gadgets needed, it was nonsense for all small values of that number. For a young entrepreneur, she looked like a remarkably average teenager as a high school student.

CMS: 2.4-sigma excess in the last gluino bin, photons+MET

Gluino, a vampire alchemist with human eyes

I just want to have a separate blog post on this seemingly small anomaly. We already saw the preprint for one day in advance but the CMS preprint finally appeared on the hep-ex arXiv:

Search for supersymmetry in final states with photons and missing transverse momentum in proton-proton collisions at 13 TeV

OK, they look at events in which two photons are created and seen in the calorimeters, plus the momentum addition doesn't seem to add up. The sum of the initial protons' \(\sum\vec p_i\) seems to differ from the final particles \(\sum \vec p_f\). The difference is the "missing transverse momentum" but because such a momentum is carried by particles which must have at least the same energy, it's also referred to as MET, the missing \(E_T\) or missing transverse energy.

Hossenfelder demands $10,000 from me through Czech lawyers

I just received a message from some Czech attorneys (a Czech subsidiary of a German firm – March 15th ***9 is a wonderful date for such a relationship) that Sabine Hossenfelder hired with her claims of defamation – concerning her expertise etc. She demands the following within 15 days:

• CZK 200,000 of compensation for hers plus CZK 24,864 for legal expenses, a bit over $10,000 in total
• removal of all my negative texts about her
• end of any publication of stuff about her in the future

otherwise she will sue and it will be worse etc.

I think it's absolutely stunning. She's on her violent campaign against the whole field that I find dear and against its practitioners and she just wants to silence me – which would mean she would continue in her campaign with a terribly weakened real opposition. It is not possible to discuss the relationship between science and the society without touching the people who are many new outlets' preferred sources.

The letter is formulated as if she demands a ransom. It adds a new level to her debatable methods to earn money.

My knowledge of the law is next to non-existent. I have no idea whether a party that is attacked in this Blitzkrieg way has an effective way to defend itself. I don't know whom I would be inviting as a witness to show that she's been helped by affirmative action, her physics is not good etc. Your recommendations are welcome. If you're extremely rich, your financial help would be welcome, too.

Strumia: audio from his famous talk on women in HEP

If you missed it, today is the Pi Day, 3/14, Albert Einstein's 140th birthday, and the Slovak Fascist State's 80th birthday!

If you want some quality 35 minutes with the Italian English, the audio from the talk by Alessandro Strumia from University of Pisa (Galileo's Alma Mater) will be interesting for you.

AdS bulk is a neural network, entanglement is a quantum gauge field

I want to mention three new papers. One of them has a cool title and the other two have some cool ideas in their bodies.



First, F. F. Faria wrote a hep-ph paper with a Conformal theory of everything. The number of papers with the ambitious titles involving "a theory of everything" is still small enough so if you want to be sure that people like me would spend at least 0.2 seconds with each page of your paper, call it "a theory of everything".

It's my policy to quickread papers with "theories of everything" in titles because it has worked for me – such a paper (not very good one) was the first paper from which I learned about Matrix theory which was rather important for me, and still is. ;-)

Sadly, the paper just writes down some action as a sum of some Standard Model, conformal gravity, and dilaton actions, with no sign of a unification or anything else that would be new and interesting. Still, good for a paper written in Brazil (an Amazon researcher is shown on the picture above).

Six photons claimed to prove that Wigner, his friend have irreconcilable views

Can a doable experiment prove that the objective reality doesn't exist?

Here's a rare example of the media hype that leads the reader to a basically correct conclusion about quantum mechanics.

As I have often argued, quantum mechanics fundamentally requires the description of the phenomena to be observer-dependent. An observer must know what he observes, what the result is, and the answers to these questions are in principle subjective. Consequently, the wave function or the density matrix, its collapse, and the precise predictions of the future measurements are subjective or observer-dependent, too. There is no way to objectively label phenomena as measurements or non-measurements and there is no viable way (and no way that would be compatible with relativity) to make the collapse of the wave function – describing the change of the observer's knowledge – as an objectively real collapse.



Wigner's friend experiment is the simplest thought experiment that shows the point. In that thought experiment (which is now claimed to become a real experiment), Eugene Wigner observes a lab in which his friend observes a quantum experiment. For the friend, the collapse occurs as soon as the friend sees something. But for Wigner himself who hasn't observed the particle inside, the system keeps on evolving as a superposition in which all options have nonzero amplitudes and are capable of reinterfering.

Nazi occupation of Czechia: 80th anniversary

Next week, Czechs will commemorate the 80th anniversary of the "dealing with the rest of Czechia" ("Erledigung der Rest-Tschechei"; yes, that terminology was intentionally picked to be degrading but Czechs have no problem with the word "Tschechei" although Germans typically think that the PC "Tschechien" is mandatory – for us, they're just synonyms) by Nazi Germany.

On March 14th, 1939, softcore Slovak clerofascists and anti-Prague nationalists, energized by their influential hardcore German friend, declared the independence and broke Czecho-Slovakia – which had already been broken by the hyphen for half a year, and which had been stripped of the Sudetenland. It was the first time when Slovakia became a country.



One window wasn't enough, Hitler greeted Prague from two windows.

On March 15th, German troops invaded Czechia and formally established the Protectorate of Bohemia and Moravia, a new "regime" that would last for 6 more years. The Third Reich was supposed to last for 1000 years but the witty Czechs renamed the occupied structure, "Protektorát" in Czech, to "Protentokrát" which looks and sounds almost the same but it means "Just for this time", correctly (with our hindsight) or optimistically (with their uncertainty) indicating the temporary character of that regime.

On March 16th, the aforementioned hardcore German comrade triumphantly arrived to the Prague Castle, declared himself the eternal master of the Milky Way, and took a couple of selfies including one above. I have felt safer in that office when then President Klaus, and not Hitler, was standing next to me. ;-)

Why inflation is a better explanation of the flatness problem than fine-tuned initial conditions

Sabine Hossenfelder tries to revive the inflation wars. She mentions two recent papers but they have really nothing to do with her main topic – and the topic is that she totally misunderstands 100% of inflation and why people consider it at all. Well, if the observation that she completely misunderstands inflationary cosmology isn't general enough for you, let me tell you something. It boils down to something even deeper: She just completely misunderstands what a "scientific explanation of anything" is and why people look for it at all.



Her final exchange with Ed Measure summarizes the situation well:

CapitalistImperialistPig: When Kepler came up with his laws of planetary motion, physicists of the day had the choice of either saying "hmmm, it seems like God like ellipses" or trying to find some deeper law that would account for them. Newton found universal gravitation and it was a great scientific advance.

Similarly, I think, cosmologists today have the choice of either saying "God likes flatness, uniform temperature,tiny initial density fluctuations, etc" or trying to find a deeper law that explains them. Inflation is such an idea.

Of course nobody has figured out exactly how to link it to deeper physics, but anybody with a better idea should chime in.

---

SH: CIP, I am afraid you entirely missed the point. I am telling you that it's not clear what you even mean by inflation "explains" it. Why do you think postulating a phase of exponential expansion is a better explanation than just postulating an exponentially small initial value?

Aside from all the wrong claims about elementary issues by the likes of her, I am greatly annoyed by the omnipresent arrogance in between the lines. She asks him "why do you think" and thus implicitly claims that the correct statement she can't understand is just "someone's opinion that is surely equal to her opinion".

But it's not just someone's opinion. It's a quantitatively demonstrable fact. One doesn't have to "think" in the sense of producing subjective or emotional guesses. Instead, one can think without quotation marks and just prove it by a simple argument. And her "opinion" is just objectively stupid. It is not something that has any importance in science whatsoever. Just like the opinion of the other 7 billion currently living people who completely misunderstand modern physics, her view is scientifically worthless.