« Sāḫt-hā-ye jahānī-ye hamkārī ». Faṣl-nāme-ye ‘olūm-e ejtemā‘ī, n° 26, été 1383/2004, pp. 1-23. [Structures mondiales de la coopération]

ye

Seek and Ye Shall Find

This chapter proposes that search engines apply a verticalizing pressure on the WWW many-to-many information distribution model, forcing this to revert to a distributive model similar to that of the mass media. The argument for this starts with a critical descriptive examination of the history of search mechanisms for the Internet. Parallel to this there is a discussion of the increasing ties b...

On the modular curves YE(7)

Let E denote an elliptic curve over Q and Y E (7) the modular curve classifying the elliptic curves E over Q such that the representations of Gal(Q/Q) in the 7-torsion points of E and of E are symplectically isomorphic. In case E is given by a Weierstraß equation such that the c 4 invariant is a square, we exhibit here nontrivial points of Y E (7)(Q). From this we deduce an infinite family of c...

Will ye no come back again?

Comments on the Sachdev-Ye-Kitaev model

We study a quantum mechanical model proposed by Sachdev, Ye and Kitaev. The model consists of N Majorana fermions with random interactions of a few fermions at a time. It it tractable in the large N limit, where the classical variable is a bilocal fermion bilinear. The model becomes strongly interacting at low energies where it develops an emergent conformal symmetry. We study two and four poin...