An example of “Official EU Agencies Falsely Report More Than 550 URLs as Terrorist Content”

Today I read Official EU Agencies Falsely Report More Than 550 URLs as Terrorist Content.  Two comments on this.

1. It happened to me in Feb 2019. I archived one of my stories from the chemical sneakernet universe. The original story is posted on Here is the message which appeared when I checked the archived link:


What? I contacted and got an answer from the webmaster, pretty fast. The problem was with, not with my link in particular. Now the archived link is available.

After I sent the message to archive but before I received the answer, I searched for a way to contact EU IRU, to ask what the problem might be.  I was unable to identify any such way. However there was a way to send a message to EU officials, who might redirect my message to whom it may concern. It worked, but it took longer than the time needed by archive webmaster to respond and unblock the link. I was not contacted since.

2. As you see in the post from archive, it was not EU IRU the institution which sent the blocking orders. But nevermind, how can one try to block arXiv articles? This reminded me of a very recent story: Google Scholar lost my Molecular computers arXiv article. As the article is on the same subject as the story from point 1, I wonder if by any (mis)chance Google Scholar received a blocking order.

System X, semantic pain and disturbing news to some

This is a temporary post. Soon some news will come, some disturbing for some. This is just to entertain you with the System X, a small graph rewrite system proposed as a replacement for slide equivalence. Here is some prose I wrote while trying to understand 3 tiny graphic beta rewrites. This qualifies as semantic pain, but it was a very good exercice because it gives ideas (to those prone to have them, as opposed to those who lack personal ideas and take them without acknowledgement).

Small graph rewrite systems (4)

This post follows Problems with slide equivalence. A solution is to replace slide equivalence with System X.

This supposes to change the decomposition of a crossing like this:


I let you discover system X (or will update later) but here I want to show you that the Reidemeister 3 rewrite looks like that:


There is now a page dedicated to small graph rewrite systems and stick-and-rings graphs.


Google Scholar lost my molecular computers

Today I noticed that my Molecular computers article arXiv:1811.04960 is replaced by Google Scholar with the unrelated article  Defining Big Data Analytics Benchmarks for Next Generation Supercomputers, arXiv:1811.02287. I’m not an author of that article.

Screenshot from 2019-04-07 21:52:00


A cosmic ray is the cause?

Google search can still find it, but Google Scholar gives the wrong result.

UPDATE: I added the article by hand, but the link to the source (i.e. arXiv article) is not present. How can they loose arXiv articles? Or more precisely  arXiv e-prints , in no place arXiv uses the name “preprint arXiv”. Maybe google scholar merged with legacy publishers, who knows, these days…

Do you experience errors in Google Scholar?

Problems with slide equivalence

UPDATE: System X is a solution.


After the Intermezzo, in this post I’ll concentrate on the slide equivalence for unoriented (virtual) links, as defined in L.H. Kauffman, Knots and Physics, World Scientific 1991, p. 336.



Later on we shall propose a small graph rewrite system which is different from this, but we first need to understand that there are some problems with slide equivalence.

Kauffman rule I’ is half a definition, half a rewrite rule. He gives two decompositions of a crossing into two 3-valent nodes. The rewrite is that we can pass from one decomposition to the other.

Problem 1. How many types of 3-valent nodes are used? My guess is just one.


Problem 2. Is the rule II’ needed at all? Why not use instead the rule III’, with the price of a loop:


Problem 3. Is the rule I’ too strong? Maybe, look at the following configuration made of two crossings.


Neighboring crossings dissappear.

We don’t even need two neighboring crossings. In the next figure I took the left pattern from the rule IV’, first part. It is also a pattern where the rules I’, then III’ apply.


The result is very different from the application of IV’.

The same happens for the right pattern of the rule IV’, first part.


We can use again I’ and III’ to obtain a very different configuration than expected.


Conclusion.  The slide equivalence rewrites with a “dumb” algorithm of rewrites application behaves otherwise than expected. By “dumb” I mean my favorite algorithms, like greedy deterministic or random.

Used with intelligence, the slide equivalence rewrites have interesting computational aspects, but what about the “intelligent” algorithm? Kauffman brains are rare.



Intermezzo (small graph rewrite systems)

Between the last post on small graph rewrite systems and a new one to follow, here are some other, real world examples of such systems.

Where is this from? Answer: M. Khovanov,   New geometrical constructions in low-dimensional topology, preprint 1990, fig. 20


Where is this from? Answer: L.H. Kauffman, Knots and Physics, World Scientific 1991, p. 336.


How can we put this in order?

computing with space | open notebook

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