Tale or story?

I’m writing a paper (due out soon…) where I employ a “gedanken-observer”, and I wanted to title a paragraph “Tale of an observer”. Or wait, is “Story of an observer” better? I would have no doubt in Italian, but I must be careful in English.

So I google “tale or story” and find several interesting contributions. This one is just OK, not very deep, and doesn’t help me resolve the controversy.

But then I find this one out, which I paste as it is:

“A tale describes a problem and the attempt to solve it, ultimately leading to success or failure in the attempt. In contrast, a story makes the argument that out of all the approaches that might be tried, the Main Character’s approach uniquely leads to success or failure. In a success scenario, the story acts as a message promoting the approach exclusively; in the failure scenario, the story acts as a message exclusively against that specific approach. Tales are useful in showing that a particular approach is or is not a good one. Stories are useful in promoting that a particular approach is the only good one or the only bad one. As a result of these differences, tales are frequently not as complex as stories and tend to be more straightforward with fewer subplots and thematic expansions. Both tales and stories are valid and useful structures, depending upon the intent of the author to either illustrate how a problem was solved with a tale or to argue how to solve a specific kind of problem with a story.”

Agree or not with this text, I find this a remarkable little piece of “the internet”.  It goes very deep into the fundamentals, the way I like. I have no idea where it actually comes from [I will update this post in case I understand more about it].

Let me expand on this. We could say that tales are pedagogical, while stories are ideological. Tales try to teach you something by example, and they are bequeathed from generation to generation without much critical inquiry. Since there is no control on the subterranean flow of tales, I would dare say that they are not ideological. Not in the sense that they are independent of ideologies (tales take up everything that is around and certainly give a representation of the “spirit of the time”: I can see this from the tales that children tell at my son’s school…), but rather that they are not the organic expression of a system’s “culture” (to the point where often tales are in sheer disagreement with the ethics of the teller…). On the other hand, stories aspire to teach how and why something happens for the good or for the bad (in this sense, the word “story” comes closer to “history”), so they are often drafted by people who certainly have a broader view, but who are nevertheless embedded a system that needs such stories to construct a narrative of its existence and purposes.

OK, I went too far. Am I writing a tale or a story? You will discover this when the paper is out. But then, what is the pedagogy I am trying to instill, or what is the ideology I am serving?

Bishop’s “The Social Turn”

[I inaugurate the new category “notes”. Posts in this category are for internal communication, and will mostly consist of sentences and excerpts taken from papers/articles I’m reading, and a few fast comments. From time to time I might go back to these notes for further commentaries]

Claire Bishop, The Social Turn: Collaboration and Its Discontents, Artforum 44, 178 (2005).

This constitutes material for the first chapter of the much lengthier book by the same author Artificial Hells: Participatory Art and the Politics of Spectatorship. A trend in contemporary art has been that of social projects where the authorship of the artist is neutralized in favour of collaborative action [as a physicist, I would say: as if it were possible! Abolishing authorship actually means to make it even much more subtle and violent, as the final figure drawn from Dogville suggests]. This in reaction to what is perceived to be the capitalist arts market, where the product is placed above the process.
The paper takes off with the following quote

“All artists are alike. They dream of doing something that’s more social, more collaborative, and more real than art. —Dan Graham”

[which we could turn it into “All scientists are alike. They dream of doing something that’s more social, more collaborative, and more useful than science”].

A few excerpts:

“There can be no failed, unsuccessful, unresolved, or boring works of collaborative art because all are equally essential to the task of strengthening the social bond. While I am broadly sympathetic to that ambition, I would argue that it is also crucial to discuss, analyze, and compare such work critically as art.”

“This emphasis on process over product (i.e., means over ends) is justified as oppositional to capitalism’s predilection for the contrary.”

“Accusations of mastery and egocentrism are leveled at artists who work with participants to realize a project instead of allowing it to emerge through consensual collaboration.”

“aesthetic judgments have been overtaken by ethical criteria”

“If the aesthetic is dangerous, isn’t that all the more the reason it should be interrogated?”

“Ethics of authorial renunciation”.

“Emphasis is shifted away from the disruptive specificity of a given work and onto a generalized set of moral precepts.”

“In the absence of a commitment to the aesthetic, Kester’s position adds up to a familiar summary of the intellectual trends inaugurated by identity politics: respect for the other, recognition of difference, protection of fundamental liberties, and an inflexible mode of political correctness.”

“We can only ever have limited access to others’ emotional and social experiences, and the opacity of this knowledge obstructs any analysis founded on such assumptions”

“Deller, Collins, Zmijewski, and Höller do not make the “correct” ethical choice, they do not embrace the Christian ideal of self-sacrifice; instead, they act on their desire without the incapacitating restrictions of guilt. In so doing, their work joins a tradition of highly authored situations that fuse social reality with carefully calculated artifice.”

“In this schema, self-sacrifice is triumphant: The artist should renounce authorial presence in favor of allowing participants to speak through him or her. This self-sacrifice is accompanied by the idea that art should extract itself from the “useless” domain of the aesthetic and be fused with social praxis”

“this denigration of the aesthetic ignores the fact that the system of art as we understand it in the West—the “aesthetic regime of art” inaugurated by Friedrich Schiller and the Romantics and still operative to this day—is predicated precisely on a confusion between art’s autonomy (its position at one remove from instrumental rationality) and heteronomy (its blurring of art and life). Untangling this knot—or ignoring it by seeking more concrete ends for art—is slightly to miss the point, since the aesthetic is, according to Rancière, the ability to think contradiction”

“For Rancière the aesthetic doesn’t need to be sacrificed at the altar of social change, as it already inherently contains this ameliorative promise.”

“Dogville: Her desire to serve the local community is inseparable from her guilty position of privilege, and her exemplary gestures perturbingly provoke an evil eradicable only by further evil. Von Trier’s film doesn’t present a straightforward moral, but articulates—through a reductio ad absurdum—one terrifying implication of the self- sacrificial position.”

“good intentions shouldn’t render art immune to critical analysis”

“these homilies unwittingly push us toward a Platonic regime in which art is valued for its truthfulness and educational efficacy rather than for inviting us—as Dogville did—to confront darker, more painfully complicated considerations of our predicament.”

[Overall, I think there never exists an aesthetics without ethics (which would make for a Platonic concept). This is a fake dualism that this paper does not resolve nor tackle. The other problem is that the paper is tailored on this particular experience without going deeper into the context of the arts in general. But still, very stimulating.]



I am doing a little spring-cleaning and tiding of my files, folders and emails, not so much to free the computer’s memory (which is infinite for all practical purposes), but rather to retrieve what was actually important in them. Among the several sketched novels, unwritten tales, unfinished scientific papers, and unsent love letters, I am amazed and amused by the amount of brief messages and notes that day-by-day I sent myself over an timespan of several years, and that infest almost every corner of my computer.

Scared of not being able of retaining pieces of information that he deems important, the myself-of-today constantly harasses the myself-of-tomorrow with plentiful messages, burdening him with the duties he was not able to tackle himself. Like a stalker, the myself-of-today chases the myself-of-tomorrow in every new environment: while some years ago he would only leave notes that opened up when logging into the computer, and that could easily be done with with CTRL+Q, now the myself-of-today attacks from all angles, sending emails, SMS messages, saving pdf files with SCREAMING.pdf titles on the Desktop, and even leaving hand-written notes (I found some in the wallet!). This is obviously unsustainable.

Fact is that emails accumulate (over 200 unread, most from myself-of-yesterday), the SMS inbox is always full, and SCREAMING.pdf files are sent to the TOREAD folder (one of many TOREAD folders, one nested into another…).

On the other hand, the myself-of-today is a real asshole.  That’s because he constantly makes promises to the myself-of-yesterday: yes of course I will look at this, I will do that, let’s be friends etc. The day after, he forgets, he procrastinates, and finally when enough time has passed he’s done with the myself-of-several-weeks-ago.

However, the myself-of-today, as a real bitch, knows perfectly well that if he wants to maintain any power on the myself-of-yesterday and on all his ancestors, every once in a while he should give him some consideration, just the little amount it takes so that the myself-of-yesterday sticks to the grand project that the myself-of-today has, keeping well in mind that such project will soon be surpassed by the one of the myself-of-tomorrow…

In all this, somehow the myself-of-several-years-ago managed to insert some messages into bottles that floated into a sea of bits and bytes of my computer. They often get lost, but somehow some of them run ashore.  Most of them contain silly or unreadable messages (“It is interesting to note that he starts from considerations about gravity. In the beginning I’m hoping for a connection of gravity to the whole story, but it’s only about Etere”), but some are full of surprises, suggestions, things that I should have thought about and that, indeed, I should have thought about.

The myself-of-right-now, right now, has the crazy idea came of keeping a permanent inventory of all the unfinished things, the aborted projects (most for good reasons…), the good and bad ideas. Let’s see what the myself-of-tomorrow will say.

A random walk…

[This was material for a very speculative broad-audience talk I gave some years ago; artwork by Francesco Vedovato]

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Brownian motion was observed by british botanist Robert Brown (1827) and used by Einstein (1905) in thermodynamics. The mean position is zero, the mean distance from origin grows with the square root of time (position isn’t distance!). Good for describing diffusion, like when you drip some drops of black ink in a glass of water and see it spreading over time. Diffusion is an irreversible process.


Brownian motion was also used by Bachelier (1900) for stocks (a version called Geometric Brownian motion hat grows on average due to inflation – Leopardi’s “magnifiche sorti e progressive”). In both cases there is a lack of information about details, modelled through noise. We don’t know the behavior of all agents on a stock market and why they do what they do. For pollen grains: lack of knowledge of detailed interactions with underlying gas molecules.


Forget about pollen grains and think about your room, which is intrinsically an open system: With tiny draughts from the windows, cosmic rays penetrating through walls, cockroaches from the tub, people stepping inside… Detailed interaction with the environment is impossible to attain. The room belongs to an environment (the house) which belongs to an environment (the city) which belongs to a country … to the Universe. What does the Universe belong to? We come back to this later…


Back to the room: if entropy is a measure of disorder, what is the entropy of my room? My mother thinks my room is very messy. It looks messy to her mental order. I think it’s not because I know exactly where things are! My mother lacks knowledge about my room state, so her measure of entropy is different from mine. Entropy is a measure of ignorance. But ignorance with respect to what? Is entropy subjective?


We could acquire information about every single object within the room, then every single atom, then describe all nucelar and subnuclear interactions, then all gravitational fields, then all quantum gravitational interactions with a theory we don’t know yet… Up to what? Strings? Loops? Can we define ignorance with respect to an ultimate “atom” of reality? Well, most people who don’t work with strings think they are a dead theory (while most people working on it thinks it is still alive). Let’s concentrate on loops.


At the heart of Quantum Gravity lies the Wheeler-De Witt equation: the Hamiltonian constraint contains the laws of physics, the wave function of the Universe describes the state of the system (one of many possible states). All of that vanishes! That’s the difference with the Schroedinger equation, where time appears.


Each portion of the universe is a clock for each other portion of the Universe (including us). The whole Universe is not a physical system! Because we can’t do physics in there. But each portion of the Universe is necessarily open. Dissipation is necessary to define time, measurement and physics. Notice that clocks have always been defined either by referring to an outer environment, or by going into the innermost depths.


… of thermodynamics:

1 – You can’t win (you can’t obtain more energy than you poured in)
2 – You can’t tie (actually dissipation occurs making energy less usable)
3 – You can’t quit the game (you cannot perfectly isolate a system)

(there’s a zero-th law but let’s leave it aside).


How entropy as ignorance increases:

– if you are given the first snapshot, you can tell right away that the system has not yet relaxed. You can tell that it is some very early time in the evolution of the system.

– if you look at the second, you can still say that it must be sooner than some time

– if you look at the last, you can’t say anything: it might be a snapshot from any moment.

Entropy growth and loss of information determine the direction of time. They lead towards thermal equilibrium.


OK for where time goes. But how is it measured? By cycles. Irreversible cycles cannot go to equilibrium. Constant production of entropy is necessary to have structures. Clocks need to to constantly stay in nonequilibrium.


Global circulation of the atmosphere due to the forcing of the sun.
Nonequilibrium steady state. Cyclic. Alive.

In the entropy balance equation in this slide:

> 0 nonequilibrium (life)
= 0 equilibrium (death)


But wasn’t entropy subjective?
Does “reality” depend on the observer?
What is the observer is no Ph.D. in physics?

And here comes my own result: If you change perspective on entropy the second law stays the same. Physical laws are in the end invariant under this symmetry: the symmetry of changing prior beliefs. Yet breaking this symmetry, and “spending” some prejudices is necessary to be able to do physics (akin to choice of reference frames or measure units). The important fact is that physics gives us a dictionary to translate between different perspectives.


What is this symmetry of physics? How we assign probabilities to things. What is the probability of The Die? Doesn’t make sense. It makes sense talking of the probability of rolling a dice. Not the object, but the process. So what is the probability of rolling the dice? Is it 1/6? Well but maybe we could have some prejudices on the die. For example we might think it is loaded. Now the entropy of the system will depend on this prejudice. And also what we will learn when we roll the die (we might learn something = flux of information = flux of heat).  Prejudice and learning will change according to prior beliefs (entropy and entropy flux). But the die will roll independently of what we think of it!

That’s what science is about: having prejudices and confronting them with facts, and updating our prejudices to newer ones. It is based on the assumption that “reality” is independent of how we describe it. Physics is not about “reality”, it is about how we measure it.


It doesn’t make sense to talk about “the entropy of an object”, or the heat released. It makes sense to talk about in that particular context, with respect to a certain experimental apparatus, “how much entropy is measured”. For example, I prefer “The Higgs mechanism” to “The Higgs boson”. Language is how we describe reality. The language of physics today is still too oriented towards objects. Native American Indians had a natural language that adapted to processes. “The passage of a cloud”, rather than “a cloud”.

“All things physical are information-theoretic in origin and this is a participatory universe. Observer participancy gives rise to information; and information gives rise to physics.” J. A. Wheeler.

Ethnicity, race and the APS meeting

I just registered to the APS March meeting. Among the questions that were asked in the application form there were my ethnicity (whether hispanic or not), and my race, to be chosen in a quite un-comprehensive list. Already I don’t understand why the hispanic is an ethnicity (therefore defined on “cultural” traits) while the others are races, defined on other sorts of traits. While the several options presented did include a box “I prefer not to answer”, I didn’t feel compelled to tick that box given that I do have an answer: that defining “races” within humankind is a failed scientific enterprise as well explained by Guido Barbujani in The invention of races. Understanding human genome diversity (which at the moment I can only find in the original Italian), the burden of two hundred years of pseudo-scientific “scholarly” practice. I wrote what a (very probably false) anectode attributes to Einstein, where he specified “human”. But then I repented: I’m not quite sure that it makes any sense at all to define “humans” as a race in the biological sense…




Insights in robustness and plasticity of metabolic phenotypes from large-scale metabolic modelling

Interesting talk by Zoran Nikoloski at LCSB, bipartite: one first very theoretical part discussing concentration robustness and a second part which remained unclear to me.

Genotypes encode metabolic networks that yield particular metabolic phenotype. Metabolic phenotype is determined by fluxes of chemical reactions and metabolite levels.  What determines metabolic fluxes? The concentration of substrates, of the active enzyme, and of other regulatory effectors (activators and repressors). Nikolski considers enzyme kinetics with mass-action law and thermodynamic constraints (he only mentions invertibility of reactions). The structure of the networks is resumed in a metabolic network and / or in the stoichiometric matrix. The space of feasible flux distributions is shrunk by analysis of genome, metabolome, thermodynamics, etc.

The plasticity of fluxes and robustness of concentrations is believed to be an important characteristic of metabolic networks. A very mathematical theorem by Shinar and Feinberg,

Shinar, G., and Feinberg, M., Structural sources of robustness in biochemical reaction networks, Science 327 (2010).

relates robustness to the so-called deficiency of the network. An analogous criterion has been devised by Nikolski and coworkers

Eloundou-Mbebi, J. M. O.; Küken, A.; Omranian, N.; Kleessen, S.; Neigenfind, J.; Basler, G.; Nikoloski, Z.: A network property necessary for concentration robustness, Nature Comm. 7 (2016).

where they write:

“Our main result is based on establishing whether or not the structural deficiency changes upon removing a single component from the network. To this end, we rely on the network obtained by eliminating a given component from each complex containing the component. Removal of a component may drastically alter the network, in terms of number of nodes, linkage classes and the rank of the stoichiometric matrix. […] The idea of removing a component from biochemical reaction network has been previously employed to make statements about the possibility of the network to exhibit multistationarity. Namely, for a given set of rate constants, it has been shown that if a reaction system obtained upon removal of a component admits multiple non-degenerated positive steady states, so does the original system. Therefore, this result may be used to identify subnetworks conferring multistationarity to the entire network. Here, we establish a connection between a structural deficiency, as a key network invariant, and ACR [Absolute Concentration Robustness] for a particular component. It is this connection that allows us to apply the results to large-scale networks, typically arising in the study of metabolism.”

Therefore it appear that this criterion would have more application to actual metabolic networks than the one devised by Feinberg. Actually, the criterion they discuss is a necessary condition for ACR and not a sufficient one:

“Consider a mass action reaction system that for given rate constants admits a positive steady state with and without removal of a component S. If the system has ACR in species S, then the systems with and without removal of S have the same structural deficiencies.”

Therefore, if removing a species modifies the deficiency of a network, then that species is certainly not robust. In their paper, they also have a very nice plot showing how many metabolites are robust across several kingdoms of life.