Archive for February 26, 2020

Clifford’s `Space-Theory of Matter’

Posted in Beards, History, mathematics, The Universe and Stuff with tags , , , on February 26, 2020 by telescoper

Well, here’s another thing I didn’t know until I was informed by Twitter.

Way back in 1876 –  forty years before Einstein presented his Theory of General Relativity – the mathematician W.K. Clifford (who is most famous nowadays for the Clifford Algebra) presented a short paper in the Proceedings of the Cambridge Philosophical Society in which he speculated that space might be described by Riemannian rather than Euclidean Geometry.

Here are a couple of excerpts:

and

The paper does not contain any actual equations, and his concentration on small scales rather than large was misguided, but it is quite remarkable that he was thinking about such matters such a long time ago!

Unfortunately Clifford died very young, in 1879, at the age of 33, tuberculosis. Had he lived longer he might have been able to develop these ideas a bit further.

As a postscript I should mention that Clifford had an impressive beard.

Ash Wednesday Observance

Posted in Uncategorized on February 26, 2020 by telescoper

So today is post-Pancake Day, or Ash Wednesday as it is sometimes known. I remember this time two years ago when I was very much a newcomer to Maynooth being quite surprised to see some folk wearing a cross marked in ash on their forehead as in the picture above. I think this practice is a tradition within the Roman Catholic Church with which Maynooth has long historical associations, so it’s not really surprising to see it here. Having been brought up in Protestant England I had never seen this before moving to Ireland, but it has become a familiar sight to me to see people with crosses on their foreheads.

Apparently the tradition used to be for ashes to be sprinkled on the top of the head of a male worshipper but a cross to be made on the forehead of a woman because she would be expected to be wearing a hat. Based on a small sample of those I have observed it seems both genders wear the cross on the forehead nowadays.

Anyway, although I’m not a Christian myself, respect to all those observing the season of Lent (Quadragesima), whether that means fasting, devotional prayer, or just giving up luxuries, such as reading this blog perhaps.

P.S. I’m told that the normal rule for Lent is `One meal and two collations’. The word collation, in the sense of ‘light meal,’ comes from the title of John Cassian‘s early fifth-century work Collationes patrum in scetica eremo (Conferences with the Egyptian hermits), which was read in Benedictine communities before a light meal. I haven’t heard that English word for a while, but it has the same origin as the Italian colazione, used in prima colazione (breakfast).