Spantools

Filippo Schiavio's programs for calculating behaviours of systems described by expressions in Span(Graph), with a graphical output, is now available at  https://sourceforge.net/projects/spantool.
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Decline and Fall

The situation of academia in Italy (if I have understood it correctly) has reached a dramatic point.

To apply for a position in future you will first need to pass a threshhold based only on numerical indicators.

To be on a committee to decide who obtains positions you will need to first past a threshhold based solely on numerical indicators.
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Why a process algebra is not an algebra of processes

I'd like to explain why I think a process algebra is not an algebra of processes.
I need to explain some minimal properties that an algebra of processes should have. Firstly finite state automata should be processes. Secondly such an algebra should have abstract operations; that is, the operation applied to isomorphic automata should produce isomorphic automata.
 I will now demonstrate why these two properties are not satisfied by process algebras.

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Coimbra and Varese Conferences

I am giving a lecture today at the ICTCS conference in Varese with title The algebra and geometry of networks in which I discuss a program written by Filippo Schiavio and work on the blocked-braid groups by Davide Maglia, two students in Como.
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The blocked-braid groups

I have described in an earlier post my work with Rosebrugh and Sabadini on tangled circuits. A tangled circuit is an arrow on the free braided monoidal category on a monoidal graph where each object (wire) of the monoidal graph is equipped with a commutative frobenius algebra structure.
In that paper we discussed as examples circuits of the form RBS where R and S are two arrows of the monoidal graph, R with domain I and S with codomain I (the unit of the tensor), and where B is a braid, that is a composite of twists tensored with identities. We call such a circuit a blocked braid on n strings.
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This Week's Overhype

Peter Woit's blog Not Even Wrong often has an entry called This Week's Hype. I noticed recently that
the verb "overhype" is creeping into the discussion. This seems to mean that hyping physics is permissible
but there are limits, namely overhyping.

I hope it never becomes necessary to introduce the term "overoverhyping".

The future of journals III

I must admit to being disappointed with the result of the popular movement to reform mathematical publishing initiated by Timothy Gowers. This is old news which I haven't commented on, that Gowers, Tao and others together with Cambridge University Press have proposed two new journals with the policy that the authors pay and that readers have free access.
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Death

This year I have been thinking quite a lot about death.
 I think this is why I stopped blogging in April.
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Holiday's end

I see that I haven't posted since April, but I have just returned from ten days holiday in the mountains and feel refreshed. Two photographs: