The directed-polymer?directed-percolation transition
We study the relation between the directed polymer and the directed percolation models, for the case of a disordered energy landscape where the energies are taken from bimodal distribution. We find that at the critical concentration of the directed percolation, the directed polymer undergoes a transition from the directed polymer universality class to the directed percolation universality class. We also find that directed percolation clusters affect the characteristics of the directed polymer below the critical concentration.
On possible experimental realizations of directed percolation
Directed percolation is one of the most prominent universality classes of nonequilibrium phase transitions and can be found in a large variety of models. Despite its theoretical success, no experiment is known which clearly reproduces the critical exponents of directed percolation. The present work compares suggested experiments and discusses possible reasons why the observation of the critical exponents of directed percolation is obscured or even impossible.
Bentham's Equality-Sensitive Utilitarianism
Rosen argues that Bentham's utilitarian doctrine was sensitive to distributive concerns and would not countenance sacrifice of fundamental individual interests for aggregate gains in happiness in society. This essay seeks to extend and deepen Rosen's argument. It is argued that Bentham's equality-sensitive principle of utility is an expression of an individualist conception of human happiness which contrasts sharply with the orthodox utilitarian abstract conception. Evidence for this interpretation of the basic motivation of Bentham's doctrine is drawn from his view of the relationship between happiness and expectations, from various expressions of his ‘each to count for one’ formula, and from his reformulations of the principle of utility itself late in his career.