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Totally agree. I was disappointed to see the article follow the trend of framing everything in life around the notion of productivity. But one can only be thankful that poor mental health is correlated with poor productivity - it means the evolutionary pressure for modern capitalist society is at least acting in the right direction...

True, but the GP suggested that you can find the absolute reference frame by looking at the relative velocities of the dots (independent of any force measurements).

Rotation is inherently about different particles moving at different velocities. This is why there is an absolute reference frame for it: it is defined by these differences, so by reducing them to zero and making every particle in the ball have the same velocity, we can reach the "absolute".

Imagine the ball is floating in space, and you are watching things through a camera fixed to the ball. To you, the two dots will always appear stationary with zero relative velocity. So there is no way to determine your absolute reference frame.

Now suppose you are watching through an external camera, and suppose you observe the dots having a relative velocity. Is the ball spinning, or is the camera orbiting around the ball? Again, there is no way to tell.

The real problem with kraits is that they enter homes in the dead of night and bite people in their sleep.

A krait in the bed is the premise for the excellent short story "Poison" by Roald Dahl.

It tastes delicious and has a fantastic aroma. It's quite complex. I'd put it somewhere between vanilla, marzipan and cinnamon. I've tried it with chocolate, almond, vanilla, fruit, cream, custard with good results. It also apparently goes well with fish (haven't tried it yet).

He can go left and come out right to demonstrate that he knows the secret - without revealing the secret

Correct

The reporter would still not know how he did it

Correct

and could not pass his conviction on to the judges

Incorrect, in this case he could pass on his conviction to the judges simply by showing them the tape where Mick goes in left and comes out right in a single unbroken take. Such a tape cannot be faked by the fake reporter.

More evenings with no sleep, coupled with a 4 hour commute (both ways) means she is exhausted.

This stood out to me - I cannot imagine the detrimental effect that 8 hours commuting per day has on one's mental health. I'm glad she was able to change jobs.

I totally agree. In fact the systems studied by social sciences are so complex that the notion of an experiment in the classical sense (hypothesis, observations, repeatability, etc) can break down completely. This is partly why the concept of qualitative research exists [1]. Some physical scientists look down on such research methods; this is a category mistake on their part.

[1] https://en.wikipedia.org/wiki/Qualitative_research (not a great article IMO but I lack the experience to give a better reference)

NYC Bike Stats 10 years ago

The surface is the data. E.g. the ridership for Lafayette Street is the upper line of the green area, minus the lower line of the green area. This is called an area chart and is used to show cumulative data and how each part contributes to the whole. In this case it shows the total NYC ridership increasing from ~7000 to ~18000 (units are unclear!), while e.g. the Central Park West ridership has remained approximately constant.

OTOH, the terrible truth is that it was necessary to order thousands of soldiers to their almost-certain deaths in order to win the war, and without a disciplined army this would not be possible. This says something about the value of discipline (in war or maths!) even when it's not obviously in your personal interest.

Walking anywhere in London or navigating the subway during rush hour means having to make a mad, dodging, aggressive dance against an oncoming tide of people, many of whom seem oblivious to Britain’s long tradition of walking on the left.

I feel obliged to point out that this 'long tradition' only exists on escalators in the London Underground. Anywhere else in the country (or London for that matter) we walk on whichever side we feel like.

Classism in America 10 years ago

However this comes with the interesting caveat that the English upper classes don't like to appear too French, especially when it comes to pronunciation, where using the foreign pronunciation can be considered rather lower class. This is reflected in class shibboleths such as:

Upper class: valet [val-ett], fillet [fill-ett]. Middle class or lower: valet [val-ay], fillet [fill-ay].

Upper class: claret [clar-ett] (from French clairet). Middle class or lower: Bordeaux.

There is definitely pedagogical value. This issue is covered by the author, but when studying ODEs for the first time, at some point the student will come across the fact that exp(x) is a solution to y' = y, which is easy enough, but needs to be convinced that exp(x) is the solution up to linear combinations. To most students this is not at all obvious! Lack of explanation here is doing the student a disservice.

There are more than 50 thousand games that end in mate! Obviously this is minuscule compared to the size of the database, but I wonder if the players really didn't see it coming, or just "allowed" their opponent to finish what might have been a nice combination?

Or maybe forced their opponent to mate under time pressure?

I hate how programming is so inconsistent. I mean, in vim I press 'w' to move one word, whereas in Notepad I press Ctrl-Right. They're not even close! I hate it when I use someone else's editor and I have to re-learn all the commands. I wish programmers could standardise this stuff. Maybe there could be a committee whose job it is to standardise editor commands, then we could program in any editor without having to worry about it.

[I'm joking of course, but only half-joking. There's a serious point to be made, which is that mathematics exists completely independently of notation. When mathematicians don't care about notation, it's because they care about the actual mathematics instead. The reason mathematics notation is non-standardised is because standardising it wouldn't really help mathematicians that much. Unfortunately this means that non-mathematicians who use mathematics suffer.]

"it may be that he was sexually attracted to her and she may not have shown enough rejection signs"

The problem is that the onus should not be on her to show rejection signs.

'I'm sorry for mugging you, I thought you were just giving me that $50 - you didn't show enough rejection signs'

Absolutely, infrastructure is the real solution. Even if the full Dutch-style bike lane is not possible, quite minor things can make a difference.

E.g. around here there are some advance cycle stop zones and advance green lights for cyclists. Both are easy to implement but make a big difference to a cyclist's safety and visibility at a junction.

What was worse was that there was no objective way to measure progress so I didn't even know if it was doing anything.

I agree that not being able to measure progress is horribly demotivating. But I find the opposite, that exercise is one of the few areas in my life where I can objectively measure progress. For example:

  Body weight
  Resting heart rate
  5k run time
  Longest distance run without stopping
  Max weight / number of repetitions / duration for strength exercises
These are all objective measurements which can be tracked over long periods of time and directly correlate with the amount and quality of training that one does. I have found that this is the best long-term way to motivate myself.