Letter to the Editor—A Simpler Proof ofL= λW

A Simple Proof of: L = λW

Letter to the EditorA statistical study of the location and motion of the HF radar cusp

The large-scale and continuous monitoring of the ionospheric cusp region offered by HF radars has been exploited in order to examine the statistical location and motion of the equatorward edge of the HF radar cusp as a function of the upstream IMF BZ component. Although a considerable scatter is seen, both parameters have a clear influence from the north-south component of the IMF. Excellent ag...

Letter to the editor

A Simpler Proof Theory for Nominal Logic

Nominal logic is a variant of first-order logic which provides support for reasoning about bound names in abstract syntax. A key feature of nominal logic is the new-quantifier, which quantifies over fresh names (names not appearing in any values considered so far). Previous attempts have been made to develop convenient rules for reasoning with the new-quantifier, but we argue that none of these...

A Simpler proof of Jensen's Coding Theorem

[82] provides a proof of Jensen's remarkable Coding Theorem , which demonstrates that the universe can be included in L[R] for some real R, via class forcing. The purpose of this article is to present a simpler proof of Jensen's theorem, obtained by implementing some changes first developed for the theory of strong coding (Friedman [87]). The basic idea is to first choose A ⊆ ORD so that V = L[...