Anecdote from the 1970s, when there used to be a sleeper service that ran from Inverness to Glasgow/Edinburgh—because the trip didn't take the whole night, they would let passengers board an hour or two before it was due to leave.
So, I'm on the Glasgow to Stirling train, going home in the evening, and I happen to be sitting behind a couple of British-Rail-as-was employees going off-shift. The conversation went as follows:
BR1: So, how was your day then? BR2: It was sh*te. BR1: Oh? BR2: Well, see, I was on the Inverness tae Glasgow sleeper, an' there was some trouble wi' the engine. So one o' my passengers wakes up, sees we're in a station, an' asks if we're in Glasgow already, an' I have to tell him, "No, we havenae left Inverness yet." BR1: Ah. BR2: So, eventually we get going, an' the driver's goin' full tilt tryin' to get us to Glasgow on time. An' we're just goin' through Larbert station at about 100 mph when we realise we've forgotten to drop the Edinburgh coaches off at Stirling...
]]>Considering that this is the book that had to be rewritten after the post-Brexit debacle convinced Charlie that he'd seriously underestimated politicians' similarity to headless chickens—yes, probably.
]]>That's not what virtual particles are. They certainly aren't "bespoke items": they have the normal quantum numbers as determined by the interaction, and if there isn't a particle with the required quantum numbers the reaction won't happen. The difference from real particles is that a virtual particle does not obey the standard relation E2 = c2p2 + m2c4, where E is the total energy, p is the momentum, m is the invariant mass, and c is the speed of light. As a result, it can only exist for a limited time, which is defined by the Heisenberg uncertainty principle ΔEΔt > ℏ/2 (in other words, you can violate the energy-momentum-mass relation by an amount ΔE provided you do so for a time less than Δt = ℏ/2ΔE, because according to the uncertainty principle such a violation isn't measurable—the 11th commandment, "thou shalt not get caught"). Virtual particles occur as internal lines in Feynman diagrams: for example, the reaction e+ + e– → μ+ + μ– goes (assuming that the centre-of-mass energy is much less than 90 GeV) by a virtual photon whose mass, in the simple case where the electron and positron have equal and opposite momenta, is equal to the total energy.
The number of distinct particles mediating a given interaction is defined by the group structure of the interaction: there is only one photon, because QED is an Abelian group (the photon mediates interactions between electric charges, but does not itself have electric charge) but there are 8 gluons, because QCD is non-Abelian (the gluon carries colour charge, and gluon-gluon interactions are possible).
The properties of the (entirely hypothetical) graviton can be deduced from the properties of gravity. It has to be massless, since gravity is a long-range force (this is the uncertainty principle at work again), and it has to have spin 2, because it is related to a rank 2 tensor and not a simple vector as the other force particles (all of which have spin 1) are. Unfortunately, gravity is not easy to describe as an exchange force—there are very fundamental mismatches between general relativity and quantum mechanics—so talking about the properties of the graviton is not really very justified.
]]>I recall Glaswegian graffiti, circa late 1970s, where it was "Jesus saves! But Dalglish scores on the rebound!"
Elderly Cynic @21 It would help a lot if they didn't regard the working hypotheses of Uncle Albert as having been written on tablets of stone and brought down from a mountain.
We don't. For example:
And, of course, Einstein was quite wrong about "hidden variables" in quantum theory.
]]>To save you wading through the technical terminology of cladistics (yuck), there is a clear account of the bottom line in Tetrapod Zoology.
The key point isn't really the time or place of origin (these are side-effects), but the fact that their analysis breaks what has been considered to be the fundamental division in dinosaur classification, between ornithischian ("bird-hipped", which confusingly doesn't include birds, but does include things like Triceratops) and saurischian ("lizard-hipped", which, er, does actually include birds). Instead, Baron et al. find that Triceratops and friends—the usual Ornithischia—group with the theropods (that's T. rex, velociraptors, and my budgie), and leave the big sauropods (traditionally grouped with the theropods in Saurischia) out on their own (well, actually grouped with the herrerasaurs, which nobody outside the field has ever heard of).
It appears to be a sound analysis, not that I have any pretensions to being a cladist, but as it's so radical it needs confirmation.
]]>Absolutely. The first motorised vehicle I ever owned (a small motorbike) met its death when someone in a minivan turned right (in the UK, so across the oncoming traffic) right in front of me and the bike wound up underneath it. The bike in question was bright pink, it had its headlight on, and I was wearing a bright yellow helmet. Van driver still didn't see me. (Fortunately, something—I still don't know what—tipped my subconscious off about what was about to happen, and I was already reaching for the brake when she turned. Braked too hard, bike skidded, I wound up sitting, undamaged apart from skinned knee, on road while bike, now on its side, disappeared under van.)
Amusing aftermath: at the time, my mother was working as a teacher of severely impaired kids at the local mental hospital. Turned out van driver was one of the doctors there. She arrived at hospital later, visibly distressed, and said "I just had a terrible experience—I nearly killed a young girl on a motorbike." "Yes," snarled my mother, "that was my daughter!" Exit doctor, stage left.
]]>My late father used to tell horror stories about the trolley buses in Huddersfield (this would have been in the 1930s). Apparently in the winter or in fog they would regularly misjudge corners and lose contact with the overhead wires, whereupon the passengers had to disembark and help push them back under...
OTOH, I've ridden trolley buses in Geneva, and they seemed fine (and must be able to cope with winter conditions, albeit in a country that does not grind to a halt after 5 cm of snow).
Sheffield has both trams and hybrid buses (nearly all the Sheffield Stagecoach double-decker buses seem to be hybrids, though the single-deckers are still diesels). There is a plan to extend the tram to a light rail, although building about 100 m of track to connect it to the rail network at Meadowhall seems to be taking more time than building the entire tram network did in the first place!
]]>The hills in Sheffield are steep enough to be annoying, but not steep enough to build into by and large (there are a few big Victorian terraces I've seen where people have dug subterranean garages, but that's about it).
The gritstone Edges around Sheffield are "near places people would want to stay", but they are also made of b**y hard rock. There are houses that look as though they're built into them, see the picture of Stoney Middleton on this page, but they're really just backed up against them for shelter.
There are plenty of caves in the Peak District, but they tend to be nasty wet places. Nice to visit, wouldn't want to live there, as they say.
]]>Yes, I know, the M80 through Glasgow is just as bad (I used to commute to Glasgow Uni from Larbert), but you would have thought that having made that mistake once would discourage the motorway planners from doing it again...
]]>An interesting feature of German is that diminutive suffices are always neuter, so words like Fraulein and Mädchen are neuter, despite referring to (young) women.
]]>That's actually one of the areas in which American English differs from British English: the Americans still apply the collective-nouns-are-singular rule, whereas we have more or less given it up, at least in everyday usage. Weinreich seems to me to be being fairly careful in distinguishing number from gender—see his remarks on the difference between mass gender, which is a singular (cheese is a dairy product), and count genders, which are plural (Edam cheeses are typically cylindrical in shape, with a red wax coating).
He is cheating in counting seven, though: what he really means is "most Yiddish dialects, including the standard one, have three genders, but I have studied an obscure dialect that has four, which do not map one-to-one on to the standard three." As far as I can see, there is no case where more than four would actually be in use.
]]>This use of the word actually has priority over the "classification by sex" use, which the Oxford English Dictionary notes as "Originally extended from the grammatical use at sense 1", so Weinreich is entitled to use it as he does. But the modern sense is so pervasive nowadays that linguists have taken to calling the grammatical concept "noun classes" instead.
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