[Introduction to] Master American History in 1 Minute a Day

Join acclaimed historian Dan Roberts--known to millions as the voice of the A Moment in Time radio series--on a bite-sized romp through 500 years of American history. With just one minute a day, you can master all the essential facts of America\u27s founding, Civil War, world conflicts, homefront transformations, and more!.https://scholarship.richmond.edu/bookshelf/1372/thumbnail.jp

A 2-Categorical Analysis of Complementary Families, Quantum Key Distribution and the Mean King Problem

This paper explores the use of 2-categorical technology for describing and reasoning about complex quantum procedures. We give syntactic definitions of a family of complementary measurements, and of quantum key distribution, and show that they are equivalent. We then show abstractly that either structure gives a solution to the Mean King problem, which we also formulate 2-categorically.Comment: In Proceedings QPL 2014, arXiv:1412.810

“We are poor,” the Czechs have realized with horror

An analysis of a debate which took place in the Czech Republic in February-March 2017 after the Czech social democratic Prime Minister Bohuslav Sobotka proposed to increase taxes for "rich people" (i.e. those who earn more than £ 20 000 pounds sterling annually) and the public realised that there are only 9 per cent of such people in the country

A Quantum Correction To Chaos

We use results on Virasoro conformal blocks to study chaotic dynamics in CFT$_2$ at large central charge c. The Lyapunov exponent $\lambda_L$, which is a diagnostic for the early onset of chaos, receives $1/c$ corrections that may be interpreted as $\lambda_L = \frac{2 \pi}{\beta} \left( 1 + \frac{12}{c} \right)$. However, out of time order correlators receive other equally important $1/c$ suppressed contributions that do not have such a simple interpretation. We revisit the proof of a bound on $\lambda_L$ that emerges at large $c$, focusing on CFT$_2$ and explaining why our results do not conflict with the analysis leading to the bound. We also comment on relationships between chaos, scattering, causality, and bulk locality.Comment: 22+6 pages, 6 figure

Open for business: what can your readers do for you? #GdnOpenWeekend

What will readers give to their newspaper in terms of money, time and data? That was the question I have been putting to loyal Guardian readers at the Open Weekend Festival at a series of workshops where they conversed with leading managers such as Alan Rusbridger (Editor), Dan Roberts (National Ed), Joanna Geary (Digital Development), Andy Miller (CEO), Janine Gibson (US Ed), Gary Younge (Correspondent) and Adam Freeman (Exec Ed Commercial). The answers were revealing