Thursday, October 30, 2008

How media and blogosphere promote crap and mock good science

I would like to review two articles on the blogosphere that completely distort the information about the quality of two technical papers about physics.

Everyone knows that the media often help to ruin the quality control in climate science - a discipline that has become extremely politicized, overrun by ideologically-driven hacks and opportunists. But we can see that glimpses of such dynamics can also be found in disciplines that have not been politicized - cosmology and theoretical physics.

The point shared by all these examples is that P.R. techniques, hype, fear, and ignorant masses manipulated by inconsistent and irrational arguments are used to overshadow the strength of fair, technical arguments.

One of the two blog articles we will look at was written by Sean Carroll who promotes their own preprint about
Dark Photons
that, as I will argue, is not scientifically valuable and brings no interesting results.

On the other hand, a Western European physicist with a blog is trying to mock a fair article about Q7-branes as
"Gibberish" (a blog post)
simply because the mathematically advanced things sound as gibberish to the author.

In both cases, the bloggers use completely irrational pseudo-arguments to improve the position of weak science and hurt the position of good science. Many of their readers whose vast majority has no idea about physics either are irrationally adopting their bloggers' views and help to create the atmosphere in which bad research is more powerful socially than good research.




Dark photons

Let me begin with the dark photons. Sean Carroll tries to lead his readers to believe that there is something new about the very idea that the dark sector - the particles species that cannot be seen in the telescopes and that make up the dark matter that only manifests itself by its gravitational effects - may include several particle species and/or a force or forces. And if this idea is not completely new, he suggests, it's been only studied for a year or so.

This is of course complete nonsense. Since the very moment when dark matter was considered for the first time, people were asking what it was made of. Quite obviously, if there are new particles, they should probably be elementary spin-0 and spin-1/2 particles or heavy spin-1 bosons supplemented with some new spin-1 (or spin-0) force carriers. The phenomenology of the dark sector is, in some sense, analogous to the phenomenology of the visible sector, i.e. the Standard Model. And the amount of creativity one needs to realize this general point is close to zero.

Every physicist knows it.

It doesn't make much sense to study these things in too much detail and to construct too contrived theories because there are clearly many options and experiments are unlikely to settle this question in a foreseeable future: in fact, it is much more likely that a full picture of dark matter will emerge from progress in pure theory - I mean string theory. Nevertheless, people have written quite a lot about the possible structure of dark matter.

The only thing that is relevant for dark matter model building is the analysis of subtle anomalies. An article to be written very soon will look at recent remarkable predictions of lepton jets (for the accelerators) that were made by combining supersymmetry with a model of dark matter designed to account for the ATIC, PAMELA, DAMA, INTEGRAL observations of dark matter. See CDF sees lepton jets?

Such models actually have a significant chance to be on the right track. This particular one requires new spin-1 bosons in a hidden sector (dark matter particles) and studies their co-existence with the LSP (a different particle) and the LSP of the minimal supersymmetric standard model. And the model actually has some results: you only choose some of its properties to agree with some anomalies and other anomalies agree automatically - and you even predict some additional, much more spectacular ones that may have been confirmed, too. ;-) You can check that Sean's paper ignores all the important empirical developments - DAMA, INTEGRAL, ATIC, PAMELA - and correspondingly, all particles have wrong spins and interactions in the model.

But let's return to some older stuff.

More than ten years ago, people have published lots of papers studying very detailed properties of dark matter sectors with additional scalar and gauge interactions. Let me mention one prominent example. In heterotic string theory, a major detailed model of all four forces investigated for more than 20 years, one may have two E8 groups in ten dimensions. One of them is broken to the Standard Model while the other E8 is "redundant" and whatever exists or happens inside this "hidden sector" only interacts gravitationally with us. For decades, people knew that the other E8 is likely to participate in supersymmetry breaking.

You know, this is like Sean Carroll's photon multiplied by 248 and coupled with "Garrett Lisi's" E8 group, except that the papers actually make sense and they were written decades before the meaningless papers by Garrett Lisi and vacuous papers by Sean Carroll.

A very representative example is Petr Hořava's 1996 paper about gluino condensation in heterotic M-theory, the correct description of strongly coupled heterotic strings he discovered with Edward Witten half a year earlier. In this setup, the Universe has two boundaries, each of them carries one E8 group, and supersymmetry could be preserved if there were one boundary only. However, it is broken by the co-existence of both of them which leads to some new interesting scaling laws etc. You know, this is a nice paper with an interesting result.

Note that the E8 sector actually plays some role here: it breaks supersymmetry. Even if it didn't play any role, it is not an ad hoc addition to the theory: its existence can be derived from heterotic strings (or from anomaly cancellation). And Hořava's paper actually leads to some non-trivial and intriguing results that can't be seen or guessed just a few seconds after you decide that the E8 sector should break supersymmetry.

Despite these intriguing results, Hořava never felt the urge to hype his discovery because he was considering dark E8-gluons that could exist inside the dark aliens and the dark E8 aliens must surely be more interesting than others. He could have also said - Wow, it's so exciting that the dark aliens have SUSY-breaking E8 gauginos in them. But he didn't. An extra E8 is simply predicted by heterotic string theory and heterotic M-theory. Even though this gauge group is actually established under certain assumptions - and not just a random guess like in Carroll's paper - it's not a new victory worth celebrating. The new victory of Hořava's paper are the promising formulae that follow from his new non-trivial global, topological effect and that are connected with other phenomenologically viable features of the model.

The existence of a new, a priori surprising twist is a feature that one cannot say about the paper by Carroll et al. In this paper, they only reveal some obvious consequences of having a dark "electromagnetism" that nevertheless seem to contradict the available observations of dark matter for reasonable choices of the parameters. So they describe this bad news in "neutral light" as upper bounds on the strength of their new interaction or the lower bounds on some masses.

You know, this is exactly the situation when a newly proposed phenomenon is not interesting in physics. If you artificially make your model of reality more complicated and more contrived, such a sacrifice should either lead to a more complete or more accurate description of reality (including new details) or it should explain some coincidences that were previously unexplained or it should solve a problem that has been interesting for some independent reasons.

The paper by Carroll et al. does neither: it is just spamming the world of phenomenology by new random useless ideas that don't seem to help anything and that don't really seem to work unless you carefully adjust their parameters for them to become invisible. The main purpose of this kind of science seems to be to make the taxpayers pay.

Humbling dark matter?

More generally, Sean's way of thinking about physics suggests that much like Lee Smolin and others, he prefers irrational hype that may impress readers who have no idea about the subject over actual scientific explanations and scientifically valuable and pretty results. For example, look at his very first sentence:
It’s humbling to think that ordinary matter, including all of the elementary particles we’ve ever detected in laboratory experiments, only makes up about 5% of the energy density of the universe.
Sorry but this is an irrational prayer similar to what can be found in low-brow journalism. In this case, it was clearly written to increase the value of papers that contain the word "dark matter" even if there is nothing interesting these papers. What's wrong with the sentence?

Well, from a scientist's viewpoint, there is nothing "humbling" about the baryonic matter being 5 times lighter than dark matter and 15 times "lighter" than dark energy. Why? Because a sensible person doesn't tie his or her body mass into his or her self-worth; Penny from The Big Bang Theory is the only one who can get an exception. ;-) What makes us humble is the "wisdom" and "complexity" that actually hides inside objects, not their mass expressed in kilograms. Do you need some examples?

An average Asian elephant weighs 5 tons or so. Should we feel humbled whenever we think about them? Well, they're just heavy but the mass is just one number and the mass is not the main (or only) determinant of humbleness. So unless you are directly threatened by elephant legs, you shouldn't exaggerate your respect to the animal.

The proton is 1836 times heavier than the electron. Most of the visible mass in the Universe is composed out of protons and neutrons. Does it mean that the electrons are 2000 times less important? Well, it doesn't.

All of chemistry - the structure of atoms, molecules, and bonds in them - depends almost exclusively on electrons and their quantum motion in pretty much classical external fields. In fact, the electrons are so important exactly because they're so light. If you want to understand why chemistry and biology works and what physical phenomena are responsible for it, be sure that you will have to study electrons most of the time. This conclusion is much more general. Lighter particles are usually more important than the heavy ones because they have long Compton wavelengths which is why they dominate long-distance physics.

In the very same way, dark matter may be 5 times heavier than the baryonic matter but that doesn't mean that in the future, physicists will have written 5 times more articles about dark matter than about the visible matter. Again, mass is not the same thing as importance.

Quite on the contrary: it can be expected that once the structure of the dark matter is understood, its physics will be fully described on a few pages of a future "complete book about physics" that will mostly talk about the visible sector. Quite likely, the textbook will only say that the dark matter is made out of neutralinos and it will mention five equations about their mass and density.

By the way, the same comments apply to the cosmological constant. Dark energy makes up 70% of the mass of the Universe but the figure 70% is just one number (that only manifests itself in the observed acceleration of the cosmic expansion). Dark energy has almost certainly no "internal structure" and a full understanding of it is equivalent to a proper calculation of one number.

At this moment, we don't know what the proper calculation is - and some people believe that we will never learn too much more about it. But whatever the correct answer will be, there is only one calculation of one number (either known or unknown to us). It is crazy to change the direction of physics because of this number. One number is just one number - as opposed to millions of numbers that the rest of physics explains - and whether the number is 1% or 70% of the total energy of the Universe doesn't influence the "intellectual" importance of this number. I am much more humbled by the "bulk" of physics that actually works and calculates even though it is relevant for 5% of the mass of the Universe only. There are so many amazing things in this bulk of physics!

We know how to describe the cosmological constant phenomenologically and the importance of the search for its underlying origin is independent of the actual percentage.

Another, related sentence in Carroll's blog article that I find unscientific is the first sentence of the second paragraph,
It’s irresistible to imagine that the dark sector might be interesting. In other words, thinking like a physicist, it’s natural to wonder whether the dark sector might be complicated, with a rich phenomenology all its own.
Well, I don't find this guess "irresistible" in any way. Quite on the contrary: I find it irresistible to imagine that it is very easy to understand what dark matter actually is. In fact, I am convinced that this is the principle that a scientist should follow. As Occam said, notions shouldn't be added unless it is necessary (to agree with observations or to increase the internal consistency of the ideas). The fact that some people find it irresistible to add useless junk that plays no role, explains nothing that we cared about previously, and leads to no surprises or interesting mathematics is troubling.

Why is Occam's razor wise? Of course, it is no fundamentalist rule that one has to obey at all times. But it is wise because whenever gears and wheels are added into our image of the Universe without a good reason, it becomes unlikely that it is the right set of gears and wheels. The more arbitrary and unjustified stuff - and independent pieces - you have in your theory, the less likely it is that your theory is correct. Why? Simply because there are many conceivable but inequivalent sets of wheels and gears and almost all of them must be incorrect (while the correct ones are equivalent to one another).

Sometimes people are lucky (or visionaries) and combine a lot of wheels and gears exactly in the right way that is proven to be true later. But one can't transform science into random guesswork. The visionaries who have made the correct "guesses" were almost never working "randomly". And in many cases, including the case of Einstein, their work was pretty much systematic inductive and deductive research and classification of possibilities.

Also, science is valuable exactly because we can get more out of it than what we inserted into it. If you must insert all the detailed - and otherwise unmotivated - assumptions about the dark sector and you can only derive some statements about the same dark sector (whose equivalence to the assumptions is pretty much obvious and guaranteed to exist from the beginning), it is a case of GIGO phenomenology: garbage in, garbage out.

Let me also say that I find it ethically problematic for a blogger to promote his own papers, especially if it must be very clear to him that the papers are not exactly "Earth-shaking", if I have to use a euphemism. In this sense, blogging may become a clash of interests.

Q7-branes

In 2007, Bergshoeff, Hartong, and Sorokin wrote a paper about Q7-branes with the following abstract:
We show how, by making use of a new basis of the IIB supergravity axion-dilaton coset, SL(2,R)/SO(2), 7-branes that belong to different conjugacy classes of the duality group SL(2,R) naturally couple to IIB supergravity with appropriate source terms characterized by an SL(2,R) charge matrix Q. The conjugacy classes are determined by the value of the determinant of Q. The (p,q) 7-branes are the branes in the conjugacy class detQ = 0. The 7-branes in the conjugacy class detQ > 0 are labelled by three numbers (p,q,r) which parameterize the matrix Q and will be called Q7-branes. We construct the full bosonic Wess-Zumino term for the Q7-branes. In order to realize a gauge invariant coupling of the Q7-brane to the gauge fields of IIB supergravity it is necessary to introduce an SL(2,R) doublet of two distinct Born-Infeld fields on the Q7-brane world-volume.
Now, every decent grad student of theoretical physics above the first year must understand this paragraph. It is very obvious that non-physicists won't get it but I assure you that the paragraph makes sense and whoever finds this paragraph inpenetrable should give up her or his dream to become a physicist.

The paper talks about more complicated types of 7-branes, introduced in the 1998 paper by Meessen and Ortin, among others. The latter has over 100 citations and is kind of similar to the 2007 paper above. You know, it is very obvious that there are many kinds of 7-branes in type IIB string theory besides D7-branes (see the classification of singular fibers in F-theory) and they are associated with monodromies. It's clear that the solutions described in these papers are a priori worth discussion even though more subtle physical phenomena may make some of them unphysical.

At any rate, these are important and well-defined tasks about the very basic objects in one of the five superstring vacua in 10 dimensions.

Now, the author of "Gibberish" modifies the abstract of the 2007 paper a little bit, using software whose proper usage she doesn't understand. It can still be seen that her abstract came from the abstract by Bergshoeff et al. And I would even claim that the content is largely preserved: even in her messed up version, the abstract makes sense. It's because the technical jargon and mathematical expressions have a very high concentration of information which is why very small snippets are often enough to reconstruct what was meant - or at least the topic that was studied.

Now, she writes that her modified abstract was "on the same level of comprehensibility" as the original text, a fact she considers "tragic" and "humorous". What I consider much more tragic is how many supervillains have advanced degrees. Graduate schools should do a better job of screening those people out ;-) and giving these degrees for actual knowledge of physics and results in physics rather than for a different type of non-brain organs than the type that most physicists have.

Journalistic brainwashing: P.R. fine-tuning of the level of complexity

As far as the sociology goes, what I find amazing are the transparent double standards that are used by the bloggers and journalists to promote mediocre research. What do I mean?

Let's ask the question: how complicated a good paper about XY should be? Now, this is a tough question because most people - and even most scientists - prefer to read simple and comprehensible papers over the tough and incomprehensible ones. On the other hand, it is very obvious that if a paper is too simple, it is probably simple-minded and cannot have the capacity to address a difficult problem properly. If a paper is written by a layman, one can usually see it right away.

Every person has a different level of complexity that he can understand or swallow. But note that the only rational, scientific way to decide whether the complexity of a paper was too low or too high to solve a problem is to objectively study the same scientific problems in detail. There is no "universal" criterion that could determine the right complexity and all "subjective" criteria are clearly irrational.

What the bloggers and journalists are doing is something different. Whenever they can withstand a higher level of complexity than their readers and to think about (slightly) more complicated concepts than the readers, they sell themselves as fantastic and irresistible cartoon heroes who are possessing special skills and who are doing something new and fascinating.

But whenever someone is doing a more demanding research than they do, they do everything they can to abuse the readers' innate hostility to complex ideas. These populist demagogues will write that the papers with higher standards than their own are gibberish, not even wrong, incomprehensible, overly complex etc.

Of course that in the hierarchy of knowledge, they will find lots of people who will agree (below them). After all, most people have no idea about science whatsoever. But you can see that if they were using this method consistently, their own work would have to be labeled as gibberish, too.

One can summarize the troubling character of their "strategy" as follows: the problem is that their research is fundamentally addressed to the less educated and less informed people: what they are doing is P.R., not science. Real science is fundamentally addressed to the smarter people or at least the peers. That's why people like the climate alarmists (who desperately try to pretend that the boring discipline of climatology is important for a common man) and most bloggers who write about science have almost nothing to do with the honest scientific approach to reality.

Democracy and expertise

If there should exist information flows between different "classes of people", it is very clear that the more "special" people in the hierarchy should try to learn what the more "ordinary" people want while the more "ordinary" people should try to learn what the more "special" people know. It's because the direction where the society goes depends on the people and not the "elites", as long as we talk about democracy, while the knowledge is associated with the "special" scientists, as long as we talk about a society where people appreciate that there exist experts and non-experts in many questions.

Whenever these two flows of information are reverted, we deal either with elitism & dictatorship or with mediocracy & idiocracy. Both of them are bad for the society.

And that's the memo.

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