The Schulz-Snyder iterative algorithm for phase retrieval attempts to recover a nonnegative function from its autocorrelation by minimizing the I-divergence between a measured autocorrelation and the autocorrelation of the estimated image. We illustrate that the Schulz-Snyder algorithm can become trapped in a local minimum of the I-divergence surface. To show that the estimates found are indeed...

Public opposition to genetically modified organisms (GMOs) remains strong. By contrast, studies demonstrate again and again that GM crops make a valuable contribution to the development of a sustainable type of agriculture. The discrepancy between public opinion and the scientific evidence requires an explanation. We argue that intuitive expectations about the world render the human mind vulner...

We present test results for the smooth lattice method using an OppenheimerSnyder spacetime. The results are in excellent agreement with theory and numerical results from other authors.

Waltz’s neorealist theories, while perhaps suitable for the systemic uses Waltz associated them with, have been often been misapplied to predict and analyze individual states’ foreign policies. This is not to say that neorealism gives no guidance to states’ foreign policies. On the contrary, even Waltz discusses foreign policy choices: the basic argument – that a bipolar world is fundamentally ...

Riemann used his analytically continued ζ-function to sketch an argument which would give an actual formula for π(x) and suggest how to prove the prime number theorem. This argument is highly unrigorous at points, but it is crucial to understanding the development of the rest of the theory. Notice that log ζ(s) = ∑ p ∑ n 1 np −ns for Re(s) > 1. Letting J(x) = ∑ pk≤x 1 k , notice that log ζ(s) =...

Tim Snyder’s ambitious Bloodlands set out to place the murderous regimes of the Third Reich and Stalin’s Soviet Union in their overlapping European contexts. Snyder proceeded from the central observation that the annihilation fantasies of Hitler and Stalin were to a large part played out in the same space: ‘in the middle of Europe, in the middle of the twentieth century, the Nazi and Soviet reg...

CARDIAC arrest is a frightening complication which may confront a surgeon at any operation. It is fortunate that it is relatively uncommon, but there is a danger of false security. Eye surgeons face this complication less frequently than general or thoracic surgeons, but few ofthose who have practised for many years have not met cases of actual or threatened cardiac arrest. Kirsch, Samet, Kugel...