A little tipple before marking Quantum Mechanics sheet 3 can be excused as a demonstration to my students about why operators don’t necessarily commute with each other. It remains to be seen what [drink,mark] turns out to be.
Yesterday, the House of Lords had a debate, among other things, on ‘Populism and Nationalism’. (Such a vague title should already smell of bullshit.) The transcript of the debate is at Hansard (and the relevant section can also be heard on iPlayer here). Among other speakers, Lord Blencathra (Conservative) gave a critical view of Obama:
Tomorrow, we will be rid of the most useless American President I have ever seen in my entire lifetime, whose only legacy is rhetoric. He has withdrawn America from the world stage and left a disastrous vacuum that has been filled by Putin and China. […] But never mind, he has his place in history: the next time I visit the United States, I will be able to use the transgender toilets.
I quote President Obama because I consider him to be a perfect example of the liberal international order which is now being routed around the world. […] Mr Timothy Garton Ash, writing in the Guardian on 13 October, says:
“Liberal internationalists have to own up: we left too many people behind”.
The phrase ‘transgender toilets’ was a reference to the North Carolina bill, whose passage now grants transgender people the right to use whichever public toilet they feel more comfortable using.
It really struck me that Lord Blencathra chose to use the issue of transgender toilets as an example of a trivial, unimportant piece of legislation pushed by ‘liberal internationalists’. Indeed the number of transgender people is relatively small, but for some reason this is taken to imply that transgender people form a sort of elite (unlike, say, Ministers of State, Members of the House of Lords, or Tory Party Chief Whips). Perhaps most worryingly, he views a civil rights victory for a discriminated-against group not as a step towards a more equal society to be celebrated, but instead, ironically, as an example of everybody else being left behind.
The legal battle for transgender rights is nowhere near won (and not to mention the cultural and social changes that will need to take place). A new bill being tabled in Texas will require transgender people to use the toilets corresponding to their birth sex, in the name of ‘common sense, common decency and public safety’. It remains to be seen what stance the new President will take, but given that the bill comes from his heartland supporters, I am not optimistic.
I have been invited to give a talk on fluid dynamics at Queens’ Mathematical Society this term. Details are yet to be decided, but the talk will be an introduction to fluids and a focus on boundary layers, including the mathematical notion of a singular limit.
While writing the talk, I thought it might be nice to have a little fun with it.
The flow of a | fluid is | governèd
By the interact-si | -on of | four main | forces:
Viscosity * gravity * inert-si- | -a and | pressure.
Depending on the context | one may | dominate an- | -other.
In fast flows | or large | lengthscales
Inert-si- | -a is | domin- | -ant
These include many im- | -portant | contexts
Such as household plumbing * oil pipelines * submar- | -ines : and the | upper | atmosphere.
Unfortunately * the | limit of | Reynolds number
Going to infinity | is a | singular | limit.
The behaviour of an in- | -viscid | fluid
Is quite different from | that of | one with low vis- | -cosity.
I read in the Independent about a group of Oxford students and activists who have occupied one of the many unused buildings around the city to house the city’s rough sleepers:
I think there is plenty of scope for a similar project at Cambridge. There are sites owned by university or colleges which lie unused. These include the former site of the Mahal and Dojo’s, next to the Mill Lane lecture theatres, which a consortium of colleges (including, I am ashamed to say, Queens’) bought four years ago with the intention of turning it into student accommodation. The existing businesses, which had been part of the fabric of Cambridge’s culture, were evicted while the colleges knew that they did not have the finances to actually build their accommodation blocks. Other sites include prime locations on Market Square, including the former pasty shop which was forced out of business by a rent increase two years ago, and has since lain dormant.
These are good examples of market failure, but a deeper fallacy is to think that these unwise decisions are bad for the owners of the buildings but hurt nobody else. An unused or abandoned building brings social costs. Homelessness is not an economic choice, but a situation of having no choice. When we remember that being housed is a human right, perhaps we will stop referring to buildings as ‘properties’ and treating them as investments.
My secondary school, CRGS, admits (or used to admit–I’m not sure now) 100 people each year (technically, 96+4). They are to be split into h = 4 houses, such that the houses have equal numbers and siblings are in the same house as each other. What happens if they have a year of fifty pairs of twins, or twenty-five sets of quadruplets?
(I believe there’s also a condition on how the four houses should be distributed evenly across the forms, but for simplicity let us ignore it.)
More serious question: Let us call an intake unresolvable if the two conditions cannot be satisfied. For a given probability distribution of twins, triplets, etc., consider the probability P(n) that an intake of hn people will be unresolvable. What values of n are local minima of P(n)?
It is more convincing, however, to read the list, prepared by Facebook itself, of a subset of the data that it collects (and saves permanently). Every search, every message, every defriending, every poke. They let you download and view a subset of this subset. For me, this download comes to around 80MB (of which around 31MB is ‘private’ messages).
A few months ago, Facebook disabled Messages on its mobile website in an attempt to get people to download the Messenger app. I refuse to do that, and because of that, I now mostly use SMS messages and emails to contact most of my friends or contacts. (There is a workaround by using the ‘basic mobile’ website, which offers limited (but sufficient) functionality.) Completely leaving Facebook has proved difficult because (a) there isn’t an adequate substitute for group chat, and (b) there are some people for whom I have no other means of contacting. When we meet new people, we no longer share contact details such as our email (or physical) addresses or phone numbers: The default is to add newly-met people on Facebook and to conduct all communication there (and asking for other contact details is seen, ironically, as too personal).
A first step towards society moving away from Facebook should be that we start sharing our contact details properly, as we used to. Mine are available on the home page of this website, and I invite you to tell me yours as well.
- For group chat, WhatsApp and Skype are problematic for the same reasons. Regretfully, IRC and XMPP are not so widely used, even though they have good merits as open and decentralised protocols. Part of the reason is that Windows and OS X do not ship with an IRC client.
- This is not primarily about privacy or security. Like any other form of communication, emails, SMS messages and IRC may be intercepted. The advantage of these systems is that they are decentralised, in the sense that your communications are not controlled by a single company. You can switch between email and mobile providers quite easily.
- Unfortunately, many people’s personal emails are from Google Mail or Yahoo! Mail, which means their email address–that is, part of their identity–is tied to Google or Yahoo!.
- Although WhatsApp and Skype promise end-to-end encryption, they are closed-source, centralised systems and you have no guarantee of it.
- Encrypting emails is relatively straightforward using tools such as Enigmail.
- While they are useful as soapboxes, Facebook, Twitter, Reddit and such are vulnerable to censorship (as discussed in Virani’s post) and therefore should not be exclusively relied upon.
- An article such as this one (written to, stored on and displayed from my personal website) is at the mercy of only my ISP (currently the SRCF at the University of Cambridge), which would have no motive in taking down this website, and even then I could switch to a different ISP. (Unless, for example, my ISP receives a court order for a takedown, for example if I write hate speech.)
- On either privacy or censorship, there is little that you can do against a sufficiently determined eavesdropper or adversary. Courts can order takedowns and intelligence services and police have the technical capability to tap lines and crack passwords. Whether they should use these privileges is a subject for policymakers, but there is no reason to give Facebook these privileges as well.
The mathematical justification for the adage ‘never read the comments’ is the notion of ‘fractal awfulness’. This says that there exist arbitrarily petty people that have misguided or bigoted views about decreasingly small communities, and that their inflammatory language and style are all self-similar to each other.
It would be interesting to look for a scaling law between ‘number of people who have/identify as X’ and ‘number of people who have a negative view of people who have/identify as X’.