Hastings at 50, from a Metropolis

A weekend trip to the quaint seaside city of Le Touquet Paris-Plage, facing the city of Hastings on the other side of the Channel, 50 miles away (and invisible on the pictures!), during and after a storm that made for a fantastic watch from our beach-side rental, if less for running! The town is far from being a metropolis, actually, but it got its added surname “Paris-Plage” from British investors who wanted to attract their countrymen in the late 1800s. The writers H.G. Wells and P.G. Wodehouse lived there for a while. (Another type of tourist, William the Conqueror, left for Hastings in 1066 from a wee farther south, near Saint-Valéry-sur-Somme.)

And the coincidental on-line publication in Biometrika of a 50 year anniversary paper, The Hastings algorithm at fifty by David Dunson and James Johndrow. More of a celebration than a comprehensive review, with focus on scalable MCMC, gradient based algorithms, Hamiltonian Monte Carlo, nonreversible Markov chains, and interesting forays into approximate Bayes. Which makes for a great read for graduate students and seasoned researchers alike!

space opera by John Scalzi [book review]

John Scalzi, author of the memorable Old Man’s War, has started a trilogy of which I only became aware recently (or more precisely became re-aware!), which has the perk of making two of the three books already published and hence available without a one or two year break. And having the book win the 2018 Locus Award in the meanwhile. This new series is yet again a space opera with space travel made possible by a fairly unclear Flow that even the mathematicians in the story have trouble understanding. And The Flow is used by guilds to carry goods and people to planets that are too hostile an environment for the “local” inhabitants to survive on their own. The whole setup is both homely and old-fashioned: the different guilds are associated with families, despite being centuries old, and the empire of 48 planets is still governed by the same dominant family, who also controls a fairly bland religion. Although the later managed to become the de facto religion.

“I’m a Flow physicist.  It’s high-order math. You don’t have to go out into the field for that.”

This does not sound much exciting, even for space operas, but things are starting to deteriorate when the novels start. Or more exactly, as hinted by the title, the Empire is about to collapse! (No spoiler, since this is the title!!!) However, the story-telling gets a wee bit lazy from that (early) point. In that it fixates on a very few characters [among millions of billions of inhabitants of this universe] who set the cogs spinning one way then the other then the earlier way… Dialogues are witty and often funny, those few characters are mostly well-drawn, albeit too one-dimensional, and cataclysmic events seem to be held at bay by the cleverness of one single person, double-crossing the bad guys. Mostly. While the second volume (unusually) sounds better and sees more action, more surprises, and an improvement in the plot itself, and while this makes for a pleasant travel read (I forgot The Collapsing Empire in a plane from B’ham!), I am surprised at the book winning the 2018 Locus Award indeed. It definitely lacks the scope and ambiguity of the two Ancillary novels. The convoluted philosophical construct and math background of Anathem. The historical background of Cryptonomicon and of the Baroque Cycle. Or the singularity of the Hyperion universe. (But I was also unimpressed by the Three-Body Problem! And by Scalzi’s Hugo Award Redshirts!) The third volume is not yet out.

As a French aside, a former king turned AI is called Tomas Chenevert, on a space-ship called Auvergne, with an attempt at coming from a French speaking planet, Ponthieu, except that is should have been spelled Thomas Chênevert (green oak!). Incidentally, Ponthieu is a county in the Norman marches, north of Rouen, that is now part of Picardy, although I do not think this has anything to do with the current novel!

Somme graves

As mentioned in a previous post, we ended up spending Easter break in the Somme, close to the part of the Western Front that opposed German and Franco-British armies  between 1914 and 1918, with horrendous human losses: the first day alone of the Battle of the Somme in July 1916 saw around 60,000 British casualties! For a final gain of less than 10 kilometres… And a total number of dead close to a million. Unsurprisingly, the area is speckled with war cemeteries and memorials. Including an Australian National Memorial which commemorates the 16,000 Australian dead during World War I, including 11,000 with unmarked graves.  As for the cemeteries near the D-day beaches, I am always deeply moved when visiting war cemeteries, uncomprehending the waste of innumerable live of young men by military stratèges unable to adapt to new forms of warfare and throwing waves of foot soldiers against impregnable machine gun nests.

When running this weekend in the quiet and green Somme countryside, surprising a young deer which fled across the immense plain, with only a few bare thickets here and there, I was also wondering at how hellish was the place a hundred years ago, at how unworldly it should have looked to the entrenched soldiers, and whether or not any of this region had kept anything in common with the pre-war era, since entire villages were more than flattened, as shown by the picture of Guillemont below…

snapshot from Amiens [#2]

church comics

During Easter break, a last minute airbnb reservation led us to visit the cathedral of Amiens (in North-East France, near the Battle of the Somme front) with its (42m) soaring ceilings and its immense nave. The central choir is surrounded by an ambulatory with niches of intricate polychrome sculptures of stories of saints that look like 3D-comics. Similar to those Jim and I already spotted in the cathedral of Chartres! In Amiens, there were several of them, including a vivid representation of the life and afterlife of Saint Fermin. (With an exhumation of his body (below) worth the visit by itself: the priest using the spade is so much into it!) As well as a life of John the Baptist, whose head was supposed to have ended up in the cathedral…