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hanche

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Retired Norwegian mathematician with an interest in computing.

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There’s an old story about that. Possibly apocryphal, but here goes:

IBM mainframes used to come with documentation in ring binders. Some pages might indeed be marked “This page intentionally blank”. And they would from time to time send out update packages to their customers, with instructions to replace pages so-and-so with the included replacements. On the replacement pages, text that had been altered would be marked with a change bar in the margin.

Lo and behold, one day an update package was received, replacing one completely blank page with one bearing the text “This page intentionally blank”. Complete with a change bar in the margin.

You can't know. However, it is a consequence of the axiom of choice (AC). You can't know if AC is true either; but mathematics without it is really really hard, so it usually assumed.

Heh. To borrow an idea from xkcd (measuring gas consumption as area): The kWh measures energy, right? And energy is force times distance. So energy divided by distance is force! Let’s all start measuring EV consumption in newtons, folks. It even makes intuitive sense: It correlates well with how hard you need to push the car to get it going at the usual travel speed. But it sucks if you need to figure out how far you can travel on a given charge.

Even worse with just two digits for the year! 01/02/03 could be 1 Feb 2003, or 2 Jan 2003, or 3 Feb 2001. Let’s just be thankful no one ever uses any of remaining three permutations.

Good point about pluralization. I tend to be confused about that because we don't pluralize units in Norwegian (except the equivalent of degrees). But confusingly, in English, you sometimes see people trying to pluralize the abbreviations, such as kgs for kilograms. Or (even worse) ms for meters. That way madness lies.

No Hello 1 year ago

I could have sworn it was Asimov, but now I’m not so sure. As I remember it, the problem was communication with astronauts in the outer reaches of the solar system.

They have a RAT (ram air turbine) that deploys automatically under specific conditions. It’s basically a turbine providing electric and hydraulic power. It was almost certainly deployed on the accident flight. It will only power the most critical equipment, though. Possibly, that does not include the ADS-B transmitter (which broadcasts position and related data).

A properly scathing resignation letter catches media attention better than anything you say after being fired, which would be interpreted by many as whining.

Indeed. Likely a wing tip strike, the right wing was ripped off, then the left wing is of course still flying so its lifting force rolls the plane over until that wing hits the ground. I think it stayed attached, so after that, the plane just slid to a stop. Edit: Saw a video, looks like the pilot flying failed to flare so they just hit the ground really hard but wings level, probably the landing gear collapsed. Not clear what caused the right wing to be removed. In any case, the plane left the frame so you couldn’t see what happened next.

I guess if we all add our favourite papers, we’ll end up with a very long list indeed. My own additions: As we may think by Vannevar Bush, and then something on Project Xanadu. There doesn’t seem to be any foundational paper on the latter, but there is Ted Nelson’s book Literary Machines.

They can, but they need to learn the proper techniques. In a country like Norway with a high proportion of electric cars, I think all fire departments know the drill by now – even if they never had to do it themselves. Most important: Don’t stop fighting the fire the moment it’s out, or it will reignite. You need to keep cooling the battery pack a long time.

sometimes the reviewer selection is an utter crap shoot

Indeed, but when someone of Tao's caliber submits a paper, any editor would (should) make an extra effort to get the very best researchers to referee the paper.

Normally, referees are unpaid. You're just supposed to do your share of referee work. And then the publisher sells the fruits of all that work (research and refereeing) back to universities at a steep price. Academic publishing is one of the most profitable businesses on the planet! But univesities and academics are fighting back. Have been for a few years, but the fight is not yet over.

It’s called the modified Julian day (MJD). And the offset is 2,400,000.5 days. In the Julian day way of counting, each day ended at noon, so that all astronomical observations done in one night would be the same Julian day, at least in Europe. MJD moved the epoch back to midnight.

https://en.wikipedia.org/wiki/Julian_day