We prove that there is a one-to-one correspondence between selfdual metrics on 3CP of positive scalar curvature admitting a non-trivial Killing field but not being conformal to LeBrun metrics, and a class of normal quartic surfaces in CP whose equations can be explicitly written down. As a consequence, we show that the moduli space of these self-dual metrics on 3CP is non-empty and diffeomorphi...

We reexamine the three-body problem in the framework of general relativity. The Newtonian N-body problem admits choreographic solutions, where a solution is called choreographic if every massive particle moves periodically in a single closed orbit. One is a stable figure-eight orbit for a three-body system, which was found first by Moore (1993) and rediscovered with its existence proof by Chenc...

The 2-category of constructively completely distributive lattices is shown to be bidual to a 2-category of generalized orders that admits a monadic schizophrenic object biadjunction over the 2-category of ordered sets.

By Löwenheim-Skolem, any theory in a countable language which admits infinite models admits models of every infinite cardinality, and indeed, models of any given cardinality elementarily equivalent to any fixed infinite model. Thus the next step in understanding the relation of elementary e equivalence is to consider models of a fixed cardinality. In this regard, the following definition captur...

This paper examines if students’ college outcomes are sensitive to access to college admissions tests. I construct a dataset of every test center location and district policy in the United States linked to the universe of individual testing records and a large sample of college enrollment records. I find evidence that SAT taking is responsive to the opening or closing of a testing center at a s...

This article examines the extent to which cultural capital helps to explain the link between social background and gaining an offer for study at the University of Oxford. We find that cultural knowledge, rather than participation in the beaux arts, is related to admissions decisions. This effect is particularly pronounced in arts subjects. We only partly support Bourdieu’s postulation of cultur...

The direct product of a free group and a polycyclic group is known to be coherent. This paper shows that every finitely generated subsemigroup of the direct product of a virtually free group and an abelian group admits a finite Malcev presentation. (A Malcev presentation is a presentation of a special type for a semigroup that embeds into a group. A group is virtually free if it contains a free...

BACKGROUND This prospective questionnaire-based study examined the post-operative symptoms encountered by children who had day case surgery at a dedicated day case surgery unit. The study evaluated the postoperative symptoms at home. The parents also evaluated the instructions given in the hospital for care at home. METHODS All children aged 1 day - 14 years operated over a one year period we...

This article refers to the results of an audit to illustrate how social enterprise rapid response teams can prevent unnecessary hospital admissions during the winter by helping patients to manage their conditions at home.

This paper investigates properties of finite sheeted covering spaces of arithmetic hyperbolic 3-orbifolds (see §2). The main motivation is a central unresolved question in the theory of closed hyperbolic 3-manifolds; namely whether a closed hyperbolic 3-manifold is virtually Haken. Various strengthenings of this have also been widely studied. Of specific to interest to us is the question of whe...