Francesco Sylos Labini

The Scientific Competitiveness of Nations

We use citation data of scientific articles produced by individual nations in different scientific domains to determine the structure and efficiency of national research systems. We characterize the scientific fitness of each nation—that is, the competitiveness of its research system—and the complexity of each scientific domain by means of a non-linear iterative algorithm able to assess quantitatively the advantage of scientific diversification. We find that technological leading nations, beyond having the largest production of scientific papers and the largest number of citations, do not specialize in a few scientific domains. Rather, they diversify as much as possible their research system. On the other side, less developed nations are competitive only in scientific domains where also many other nations are present. Diversification thus represents the key element that correlates with scientific and technological competitiveness. A remarkable implication of this structure of the scientific competition is that the scientific domains playing the role of “markers” of national scientific competitiveness are those not necessarily of high technological requirements, but rather addressing the most “sophisticated” needs of the society.

On the Fractal Structure of Galaxy Distribution and its Implications for Cosmology

Two fundamental empirical laws have been established in the analysis of galaxy space distribution. First, recent analyses have revealed that the three dimensional distribution of galaxies and clusters is characterized by large scale structures and huge voids: such a distribution shows fractal correlations up to the limits of the available samples. This has confirmed the earlier de Vaucouleurs power-law density - distance relation, now corresponding to a fractal structure with dimension

The complex universe: recent observations and theoretical challenges

D \approx 2

Power-law correlation and discreteness in cosmological N-body simulations

, at least, in the range of scales

Universal properties of violently relaxed gravitational structures

\sim 1 ÷200 Mpc

Statistical Physics for Complex Cosmic Structures

(

Biasing in Gaussian random fields and galaxy correlations

H_0 = 55 km/sec/Mpc

Statistical Physics for cosmic structures

). An eventual cut-off towards homogenization has not been yet identified. Second, since Hubbles discovery, the linear redshift-distance law has been well established within

Violent relaxation of ellipsoidal clouds

200 Mpc

On the generation of triaxiality in the collapse of cold spherical self-gravitating systems

and also much deeper. The co-existence of these laws within the same scales is a challenge for the standard cosmology where the linear Hubble law is a strict consequence of homogeneity of the expanding universe. This puzzle is now sufficiently strong to raise doubts for the standard cosmology.