Abstract:
the goal of this paper is to analyze, with an anthropological approach, the complex relations between land identity and quality of food, as well as the organization of the stakeholders to certify food quality and the economic opportunities linked to the cultural value of these food products. the symbolic value of food products is taken into account as a relevant data to analyze consumers, choices and the role of food in the building up of individual and social identities. it is outlined that the methods to establish origin labels can not be copied; each product, each situation, demands special analysis. the kind of market, the institutions, the knowledge and techniques, the norms and rules, will modify the qualificationo process of products. the conclusions analyze the opposed/complementary relations between: (i) identity and quality/the interest to increase the symbolic value, the cultural density, of local products; (ii) between tradition and innovation/the interest to identify and analyze local innovations and skills (iii) between local products and standard products / the interest to take in to account the oppositions and complementarities between them.

Abstract:
kant and mendelssohn published almost simultaneously influential essays on the enlightenment. i use this historical contingency as occasion to reflect on the presuppositions and implications their views have with respect to philosophy and politics. in the first part, i compare mendelssohn's discursive strategy with that of traditional liberalism. a contradiction emerges from this contrast, which, in the second part, i interpret in kantian terms as an antinomy of modern political reason. kant's notion of "autonomy," i suggest, is an attempt to overcome this very antinomy. putting things this way allows us to better appreciate the originality of kant's defense of the free use of public reason and his contribution to the liberal tradition.

Abstract:
Kant y Mendelssohn publicaron, casi simultáneamente, influyentes ensayos sobre el significado de la Ilustración. Aprovecho esta contingencia histórica para reflexionar sobre los presupuestos e implicaciones que estas ensayos tienen respecto a la filosofía y la política. En la primera parte, comparo la estrategia discursiva de Mendelssohn con la del liberalismo tradicional. Del contraste surge una contradicción que, en la segunda parte, interpreto en términos kantianos como una antinomia de la razón política moderna. Sugiero entender la noción de "autonomía" en Kant como respuesta y superación de esta antinomia. Ver las cosas de este modo nos permite apreciar mejor la originalidad de la defensa kantiana del uso libre de la razón pública y su contribución a la tradición liberal. Kant and Mendelssohn published almost simultaneously influential essays on the Enlightenment. I use this historical contingency as occasion to reflect on the presuppositions and implications their views have with respect to philosophy and politics. In the first part, I compare Mendelssohn's discursive strategy with that of traditional liberalism. A contradiction emerges from this contrast, which, in the second part, I interpret in Kantian terms as an antinomy of modern political reason. Kant's notion of "autonomy," I suggest, is an attempt to overcome this very antinomy. Putting things this way allows us to better appreciate the originality of Kant's defense of the free use of public reason and his contribution to the liberal tradition.

Abstract:
Randomness in the sense of Martin-L\"of can be defined in terms of lower semicomputable supermartingales. We show that such a supermartingale cannot be replaced by a pair of supermartingales that bet only on the even bits (the first one) and on the odd bits (the second one) knowing all preceding bits.

Abstract:
We consider the universal Grigorchuk 2-group, i.e., the group such that every Grigorchuk 2-group is a quotient. We show that this group has a nice universal representation in the group of all functions f:{0,1,2}^N --> Aut(T_2), where T_2 is a group of automorphism of the binary tree. Finally, we prove that this universal Grigorchuk 2-group is amenable. The proof is an application of the ``Munchhausen trick'' developed by V. Kaimanovich.

Abstract:
Our food heritage is not only limited to food products and production techniques, it also includes the consumption skills and technologies (CST) used to obtain what the consumer requires from a food product. In a specific food culture, a given food product is linked to specific CSTs. In this paper, we examine this aspect of food heritage through the examples of raw ham in Italy, France and Spain, rice varieties and chocolate. We then discuss two types of conjunction / disjunction between food products and food CSTs: controlled diffusion and diffusion through education. We conclude that the sustainability of localized, “origin” or “terroir” products depends on the existence of skilled consumers. The transmission and diffusion of these skills and technologies are thus factors in the permanence and diffusion of the product itself. Le patrimoine alimentaire n’est pas constitué exclusivement de produits et de techniques de production, mais aussi de compétences et techniques de consommation (CTC) utilisées par les consommateurs pour obtenir d’un produit alimentaire l’utilité ou le service qu’ils en attendent. Dans une culture alimentaire donnée, un produit alimentaire spécifique est lié à des CTC spécifiques. Cette dimension du patrimoine alimentaire est examinée à travers les exemples du jambon cru en Italie, en Espagne et en France, de différents riz, et du chocolat. Nous discutons ensuite deux types de cohérences / incohérences entre produits et CTC : contr le par la source, diffusion par l’éducation. Nous concluons que la durabilité de produits locaux, d’origine ou de terroir dépend de l’existence de consommateurs compétents. La transmission et la diffusion des compétences et techniques de consommation sont donc des facteurs de la pérennité et de la diffusion du produit lui-même.

Abstract:
Solomonoff's central result on induction is that the posterior of a universal semimeasure M converges rapidly and with probability 1 to the true sequence generating posterior mu, if the latter is computable. Hence, M is eligible as a universal sequence predictor in case of unknown mu. Despite some nearby results and proofs in the literature, the stronger result of convergence for all (Martin-Loef) random sequences remained open. Such a convergence result would be particularly interesting and natural, since randomness can be defined in terms of M itself. We show that there are universal semimeasures M which do not converge for all random sequences, i.e. we give a partial negative answer to the open problem. We also provide a positive answer for some non-universal semimeasures. We define the incomputable measure D as a mixture over all computable measures and the enumerable semimeasure W as a mixture over all enumerable nearly-measures. We show that W converges to D and D to mu on all random sequences. The Hellinger distance measuring closeness of two distributions plays a central role.

Abstract:
Solomonoff's central result on induction is that the posterior of a universal semimeasure M converges rapidly and with probability 1 to the true sequence generating posterior mu, if the latter is computable. Hence, M is eligible as a universal sequence predictor in case of unknown mu. Despite some nearby results and proofs in the literature, the stronger result of convergence for all (Martin-Loef) random sequences remained open. Such a convergence result would be particularly interesting and natural, since randomness can be defined in terms of M itself. We show that there are universal semimeasures M which do not converge for all random sequences, i.e. we give a partial negative answer to the open problem. We also provide a positive answer for some non-universal semimeasures. We define the incomputable measure D as a mixture over all computable measures and the enumerable semimeasure W as a mixture over all enumerable nearly-measures. We show that W converges to D and D to mu on all random sequences. The Hellinger distance measuring closeness of two distributions plays a central role.

Abstract:
In this paper we extend the construction of random walks with a prescribed Poisson boundary to the case of measures in the class of a generalized Gibbs state. The price for dropping the $\alpha$-quasiconformal assumptions is that we must restrict our attention to CAT($-\kappa$) groups. Apart from the new estimates required, we prove a new approximation scheme to provide a positive basis for positive functions in a metric measure space.

Abstract:
This paper contains some results of An.A.Muchnik (1958-2007) reported in his talks at the Kolmogorov seminar (Moscow State Lomonosov University, Math. Department, Logic and Algorithms theory division, March 11, 2003 and April 8, 2003) but not published at that time. These results were stated (without proofs) in the joint talk of Andrej Muchnik and Alexei Semenov at Dagstuhl Seminar 03181, 27.04.2003-03.05.2003. This text was prepared by Alexey Chernov and Alexander Shen in 2008-2009. We consider (in the framework of algorithmic information theory) questions of the following type: construct a message that contains different amounts of information for recipients that have (or do not have) certain a priori information. Assume, for example, that the recipient knows some string $a$, and we want to send her some information that allows her to reconstruct some string $b$ (using $a$). On the other hand, this information alone should not allow the eavesdropper (who does not know $a$) to reconstruct $b$. It is indeed possible (if the strings $a$ and $b$ are not too simple). Then we consider more complicated versions of this question. What if the eavesdropper knows some string $c$? How long should be our message? We provide some conditions that guarantee the existence of a polynomial-size message; we show then that without these conditions this is not always possible.