Arab-Islamic reception of Hellenistic science

This article is an overview of the Arab-Islamic reception and development of Hellenistic science. It particularly refers to mathematics, physics and astronomy. It focuses on the following topics: 1) Two interpretative models of this reception in the 19th, 20th, and 21st century scholarship: the “Indo-European model” (which supposes a cultural heterogeneity between Greece and Islam) and the “cosmopolitan Hellenistic model” (which supposes homogeneity between the two). 2) The channels through which Hellenistic science was transmitted to the Islamic world: the philological channel, and the oral channel which implies the pre-existence of a common Greek-Semitic cultural ground that made this transmission possible. 3) Three features of the Arab-Islamic sciences that highlight their essential contribution to the emergence of modern science in 16th and 17th century Europe: 3.1. The “democratising” character of the Arab-Islamic sciences resulting from a larger diffusion of literacy. 3.2. The higher precision of measurements and calculations. 3.3. The experimental approach of Muslim scientists. A positive role in the accomplishment of these advances has been played by the non-metaphysical character of orthodox Islamic monotheism. According to Muslim orthodoxy, there are no Neo-Platonic intermediaries between the almighty God and his creation. The whole universe is submitted to the same physical laws. I argue that today it is important to open an interdisciplinary debate on the Arab-Islamic sciences. It would certainly lead to a better appreciation of their historical contribution. It could also suggest answers to contemporary epistemological impasses deriving from the growing gap between the humanities and the sciences.status: publishe

Generalized Lazarsfeld-Mukai bundles and a conjecture of Donagi and Morrison

Let S be a K3 surface and assume for simplicity that it does not contain any (-2)-curve. Using coherent systems, we express every non-simple Lazarsfeld-Mukai bundle on S as an extension of two sheaves of some special type, that we refer to as generalized Lazarsfeld-Mukai bundles. This has interesting consequences concerning the Brill-Noether theory of curves C lying on S. From now on, let g denote the genus of C and A be a complete linear series of type g^r_d on C such that d<= g-1 and the corresponding Brill-Noether number is negative. First, we focus on the cases where A computes the Clifford index; if r>1 and with only some completely classified exceptions, we show that A coincides with the restriction to C of a line bundle on S. This is a refinement of Green and Lazarsfeld's result on the constancy of the Clifford index of curves moving in the same linear system. Then, we study a conjecture of Donagi and Morrison predicting that, under no hypothesis on its Clifford index, A is contained in a g^s_e which is cut out from a line bundle on S and satisfies e<= g-1. We provide counterexamples to the last inequality already for r=2. A slight modification of the conjecture, which holds for r=1,2, is proved under some hypotheses on the pair (C,A) and its deformations. We show that the result is optimal (in the sense that our hypotheses cannot be avoided) by exhibiting, in the Appendix, some counterexamples obtained jointly with Andreas Leopold Knutsen.Comment: 28 pages, final version, to appear in Adv. Math. with an Appendix joint with Andreas Leopold Knutse

What Money Can't Buy: The Relevance of Income Redistribution for Functioning Levels

well-being, functionings, equivalence scale, equivalent income

Factor Analysis vs Fuzzy Sets Theory: Assessing the Influence of Different Techniques on Sen's Functioning Approach.

This paper explores a couple of specific operational interpretations of Sen's approach in view of assessing the extent to which the results originated by the implementation of Sen's concepts are influenced by the choice of the specific technique. By means of a survey based on a representative sample of Belgian individuals, seven achieved functioning's are identified via each technique and subsequently confronted. To structure the information and to facilitate comparisons, standard multivariate analysis is performed, while at the same time considering in more detail the sub-group of the most deprived individuals. In this way, a substantial accordance - yet no perfect equivalence - is uncovered in the general patterns of functioning's' achievements.

Factor Analysis vs. Fuzzy Sets Theory: Assessing the Influence of Different Techniques on Sen's Functioning Approach

This paper explores a couple of specific operational interpretations of Sen's approach in view of assessing the extent to which the results originated by the implementation of Sen's concepts are influenced by the choice of the specific technique. By means of a survey based on a representative sample of Belgian individuals, seven achieved functioning's are identified via each technique and subsequently confronted. To structure the information and to facilitate comparisons, standard multivariate analysis is performed, while at the same time considering in more detail the sub-group of the most deprived individuals. In this way, a substantial accordance - yet no perfect equivalence - is uncovered in the general patterns of functionings' achievements.

The triggering of starbursts in low-mass galaxies

Strong bursts of star formation in galaxies may be triggered either by internal or external mechanisms. We study the distribution and kinematics of the HI gas in the outer regions of 18 nearby starburst dwarf galaxies, that have accurate star-formation histories from HST observations of resolved stellar populations. We find that starburst dwarfs show a variety of HI morphologies, ranging from heavily disturbed HI distributions with major asymmetries, long filaments, and/or HI-stellar offsets, to lopsided HI distributions with minor asymmetries. We quantify the outer HI asymmetry for both our sample and a control sample of typical dwarf irregulars. Starburst dwarfs have more asymmetric outer HI morphologies than typical irregulars, suggesting that some external mechanism triggered the starburst. Moreover, galaxies hosting an old burst (>100 Myr) have more symmetric HI morphologies than galaxies hosting a young one (<100 Myr), indicating that the former ones probably had enough time to regularize their outer HI distribution since the onset of the burst. We also investigate the nearby environment of these starburst dwarfs and find that most of them ($\sim$80$\%$) have at least one potential perturber at a projected distance <200 kpc. Our results suggest that the starburst is triggered either by past interactions/mergers between gas-rich dwarfs or by direct gas infall from the IGM.Comment: 21 pages, 8 figures, 6 tables, accepted for publication in MNRA