Molecular computers in real life

A molecular computer [1]  is a single molecule which transforms into a predictable another one, by a cascade of random chemical reactions mediated by a collection of enzymes, without any external control.


We could use the artificial chemistry chemlambda to build real molecular computers. There is a github repository [2] where this model is implemented and various demos are available.

By using molecular bricks which can play the role of the basic elements of chemlambda we can study the behaviour of real molecules which suffer hundreds or thousands of random chemical reactions, but without having to model them on supercomputers.
A molecule designed like this will respect for a while the chemlambda predictions… We don’t know for how much, but there might be a window of opportunity which would allow a huge leap in synthetic biology. Imagine instead of simple computations with a dozen of boolean gates, the possibility to chemically compute with recursive but not primitive recursive functions.

More interesting, we might search for chemlambda molecules which do whatever we want them to do. We can build arbitrarily complex molecules, called chemlambda quines, which have all the characteristics of living organisms.

We may dream bigger. Chemlambda can unite the virtual and the real worlds… Imagine a chemical lab which takes as input a virtual chemlambda molecule and outputs the real world version, much like Craig Venter’s printers. The converse is a sensor, which takes a real chemical molecule, compatible with chemlambda and translates it into a virtual chemlambda molecule.

Applications are huge, some of them beneficial and others really scary.

For example, you may extend your immune system in order to protect your virtual identity with your own, unique antibodies.

As for using a sensor to make a copy of yourself, at the molecular level, this is out of reach in the recent future, because the real living organism works by computations at a scale which dwarfs the human technical possibilities.

The converse is possible though. What about having a living computer, of the size of a cup, which performs at the level of the whole collection of computers available now on Earth? [3]


[1] this is the definition which I use here, taken from the articles Molecular computers and Build a molecular computer (2015)


[3] The internet can be your pet

How I hit a wall when I used the open access and open source practices when applying for a job

UPDATE 11.10.2015. What happened since the beginning of the “contest”? Nothing. My guess is that they are going to follow the exact literary sense of their announcement. It is a classic sign of cronyism. They write 3 times that they are going to judge according to the file submitted (the activity of the candidate as it looks from the file), but they don’t give other criteria than the ones from an old law. In my case I satisfy these criteria, of course, but later on they write about “candidates considered eligible”, which literary means candidates that an anonymous board considers they are eligible and not simply eligible according to the mentioned criteria.

Conclusion: this is not news, is dog bites man.

I may be wrong. But in the case I’m right then the main subject (namely what happens in a real situation with open access practices in case of a job opening) looks like a frivolous, alien complaint.

The split between:
– a healthy, imaginative, looking to the future community of individuals and
– a kafkian old world of bureaucratic cronies
is growing bigger here in my country.


UPDATE 14.10.2015: Suppositions confirmed. The results have been announced today, only verbally, the rest is shrouded in mystery. Absolutely no surprise. Indeed, faced with the reality of local management, my comments about open access and open source practices are like talking about a TV show to cavemen.

Not news.

There is a statement I want to make, for those who read this and have only access to info about Romanians from the media, which is, sadly, almost entirely negative.

It would be misleading to judge the local mathematicians (or other creative people, say) from these sources. There is nothing wrong with many Romanian people. On the contrary, these practices which show textbook signs of corruption are typical for the managers of state institutions from this country. They are to be blamed. What you see in the media is the effect of the usual handshake between bad leadership and poverty.

Which sadly manifest everywhere in the state institutions of Romania, in ways far beyond the ridicule.

So next time when you shall interact with one such manager, don’t forget who they are and what they are really doing.

I am not going to pursue a crusade against corruption in Romania, because I have better things to do. Maybe I’m wrong and what is missing is more people doing exactly this. But the effects of corrupt practices is that the state institution becomes weaker and weaker. So, by psycho historic reasons 🙂 there is no need for a fight with dying institutions.

Let’s look to the future, let’s do interesting stuff!


This is real: there are job openings at the Institute of Mathematics of the Romanian academy, announced by the pdf file

The announce is in Romanian but you may notice that they refer to a law from 2003, which asks for a CV, research memoire, list of publications and ten documents, from kindergarden to PhD. On paper.

That is only the ridicule of bureaucracy, but the real problems were somewhere else.

There is no mention of criteria of selection, members of the committee, but in the announcement is written 3 times that every candidate’s work will be considered only as it appears from looking at the file submitted.

They also ask that the scientific, say, part of the submission to be sent by email to two addresses which you can grasp from the announcement.

So I did all the work and I hit a wall when I submitted by email.

I sent them the following links:

– my homepage which has all the info needed (including links to all relevant work)

– link to my arxiv articles
because all my published articles and all my cited articles, published or not) are available at arXiv

– link to the chemlambda repository for the programming, demos, etc part

I was satisfied because I finished this, when I got a message from telling me that I have to send them, as attachment, the pdf files of at least 5 relevant articles.

In the paper file I put 20+ of these articles (selected from 60+), but they wanted also the pdf files.

I don’t have the pdfs of many legacy published articles because they are useless for open access, you can’t distribute them publicly.
Moreover I keep the relevant work I do as open as possible.

Finally, how could I send the content of the github repository? Or the demos?

So I replied by protesting about the artificial difference he makes between a link and the content available at that link and I sent a selection of 20 articles with links to their arXiv version.

He replied by a message where he announced that if I want my submission to be considered then I have to send 5 pdfs attached.

I visited physically Dan Timotin to talk and to understand why a link is different from the content available to that link.

He told me that these are the rules.

He told that he is going to send the pdfs to the members of the committees and it might happen that they don’t have access to the net when they look for the work of the candidate.

He told me that they can’t be sure that the arXiv version is the same as the published version.

He has nothing to say about the programming/demo/animations part.

He told that nobody will read the paper file.

I asked if he is OK if I make public this weird practice and he agreed to that.

Going back to my office, I arrived to find 9 pdfs of the published articles. In many other cases my institute does not have a subscription to journals where my articles appeared, so I don’t think that is fair to be asked to buy back my work, only because of the whims of one person.

Therefore I sent to Dan Timotin a last message where I attached these 9 pdfs, I explained that I can’t access the others, but I firmly demand that all the links sent previously to be sent to the (mysterious, anonymous, net deprived, and lacking public criteria) committee, otherwise I would consider this an abuse.

I wrote that I regret this useless discussion provoked by the lack of transparency and by the hiding behind an old law, which should not stop a committee of mathematicians to judge the work of a candidate as it is, and not as it appears by an abuse of filtering.

After a couple of hours he replied that he will send the files and the links to the members of the committee.

I have to believe his word.

That is what happens, in practice, with open access and open science, at least in some places.

What could be done?

Should I wait for the last bureaucrat to stop supporting passively the publishing industry, by actively opposing open access practices?

Should I wait for all politicians to pass fake PhDs under the supervision of a very complacent local Academia?

Should I feel ashamed of being abused?

Deterministic vs random, an example of grandiose shows vs quieter, functioning anarchy

In the following video you can see the deterministic, at the right random evolution of the same molecule, duplex.mol from the chemlambda repository. They take about the same time.

The deterministic one is like a ballet, it has a comprehensible development, it has rhythm and drama. Clear steps and synchronization.

The random one is more fluid, less symmetric, more mysterious.

What do you prefer, a grand synchronized show or a functioning, quieter anarchy?

Which one do you think is more resilient?

What is happening here?

The molecule is inspired from lambda calculus. The computation which is encoded is the following. Consider the lambda term for the identity function, i.e. I=Lx.x. It has the property that IA reduces to A for any term A. In the molecule it appears as a red trivalent node with two ports connected, so it looks like a dangling red globe. Now, use a tree of fanouts to multiply (replicate) this identity 8 times, then build the term


Then use one more fanout to replicate this term into two copies and reduce all. You’ll get two I terms, eventually.
In the deterministic version the following happens.

– the I term (seen as a red dangling node) is replicated (by sequence of two rewrites, detail) and gradually the tree of fanouts is destroyed

– simultaneously, the tree of applications (i.e. the syntactic tree of the term, but seen with the I’s as leaves) replicates by the fanout from the end

– because the reduction is deterministic, we’ll get 16 copies of I’s exactly when we’ll get two copies of the application tree, so in the next step there will be a further replication of the 16 I’s into 32 and then there will be two, disconnected, copies of the molecule which represents ((II)(II))((II)(II))

– after that, this term-molecule reduces to (II)(II), then to II, then to I, but recall that there are two copies, therefore you see this twice.

In the random version everything mixes. Anarchy. Some replications of the I’s reach the tree of applications before it has finished to replicate itself, then reductions of the kind II –> I happen in the same time with replications of other pieces. And so on.
There is no separation of stages of this computation.
And it still works!

I used quiner_experia, with the mol file duplex.mol. The first time I modified all the weights to 0 (to have deterministic application) and took the rise parameter=0 (this is specific to quiner_experia, not present in quiner) too, because the rise parameter lower the probabilities of new rewrites, exponentially, during the same step, in order to give fair chances to any subset of all possible rewrites possible.
Then I made a screencast of the result, without speeding it, and by using safari to run the result.
For the random version I took all the weights equal to 1 and the rise parameter equal to 8 (empirically, this gives the most smooth evolution, for a generic molecule from the list of examples). Ran the result with safari and screencasted it.
Then I put the two movies one near the other (deterministic at left, random at right) and made a screencast of them running in parallel. (Almost, there is about 1/2 second difference because I started the deterministic one first, by hand).
That’s it, enjoy!
For chemlambda look at the trailer from the collections of videos I have here on vimeo.

Replication, 4 to 9

In the artificial chemistry chemlambda  there exist molecules which can replicate, they have a metabolism and they may even die. They are called chemlambda quines, but a convenient shorter name is: microbes.
In this video you see 4 microbes which replicate in complex ways. They are based on a simpler microbe whose life can be seen live (as a suite of d3.js animations) at [1].
The video was done by screencasting the evolution of the molecule 5_16_quine_bubbles_hyb.mol and with the script quiner_experia, all available at the chemlambda GitHub repository [2].

[1] The birth and metabolism of a chemlambda quine. (browsers recommended: safari, chrome/chromium)

[2] The chemlambda repository:

In the mood for a rant: attention conservation notices

I see attention conservation notices at the beginning of posts  belonging to some rather interesting collections. And I wonder: what is the goal of the author of such announcements?

Should I put one too?

Well, if I would put one, then it would be like this:

Wait, let me first give you some context, in the form of a rant. Then I’ll write down the attention conservation notice.

Context. I am one of those researchers who want to create new things, in new ways, in this new connected world. I got in love with the Net the first time I saw a glimpse of it.

My position is the following: research needs to pass by a liberating process exactly like art did a hundred years ago. At a much bigger scale, of course, but the idea is the same.

Much like a revolutionary impressionist at the time of the Art Academies, this is a thrilling and also ridiculous position.

Besides the mediocre but respectable art channels provided by the exhibitions of art academies, there is only worse. The revolutionary painters did have the street to show their works. On the street, the cute portraits and the boooring visual memes are the rule. Not to say also that, on the street there are many other revolutionaries who are either too cool to paint, or just looking for relief from the monkey inheritance who pushes all of us to pretend we are really different.

Art academies are full of good, but statistically mediocre painters, who want to advance in their career with great determination. For them painting is not the goal, but the means towards ensuring a comfortable life. They are job oriented, like everybody else on the street. They speak the language of the street: they are professionals who, incidentally, spend their time splatting pigments on rectangular surfaces. The works are then reviewed by other professionals and finally shown (at different heights, the best ones at the eye level) to their peers, mostly.

Also  to anybody else willing to spend a free afternoon in a pleasant way, by visiting a reputable exhibition. Going back home, then, acquainted with the professional artistic last trends, the enlightened art lover may pick, from the street, something which is surely less expensive, but cute enough or modern enough to deserve the eye level place in the art lover’s home.

These guys are certainly not going to feed a Van Gogh, except by accident. First because is on the street. Secondly because it does not look professional, don’t you see that the guy uses randomly splashed colours, and worse even, you can see the traces of the brushes, instead of the polished, varnished, shitty brown finish. Thirdly, look at that cuute little boy pissing! Or that cat, btw.

You see where I’m going, right? The art lover just wants to spend some pleasant time off work. Just want to feel he or she has human interests. And to show to the Joneses he or she has that special artistic bend.

Now tell me, is an attention conservation notice going to help? Certainly, for somebody who does 5 min portraits for a living. And for that portraits, not for the other stuff. Not for the really good stuff, because the really good stuff takes work to appreciate it.

In conclusion, even if I wish sometimes to put the following attention notice:

This is openly shared work. You have to sweat to get it. If you are an academic looking for promotion please don’t steel it because you’ll be easy to find. If you are just looking for distraction then watch TV, not this post. If you want to discuss then do it after you spent the time to accommodate with the content, you clicked, read and understood all sources. Because otherwise you either show disrespect for my work or you look stupid

but I refrain from it.

Who wants to make a movie?

This animation is done on my laptop (a macbook pro), with scripts which are freely available at the chemlambda repository here.

No supercomputer, nor any costly device has been used to make it…

So, who wants to make a movie?

Other demos which utilise the new experia version: