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bertrandsballot.bsky.social
High school math teacher. Fun lover. And by fun I mean building homes, protected bike lanes, funding transit and other things that are good for people. Also board games.
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Today, I am feeling contemptuous of Americans for being so ill-informed. Not the best feeling. So back to work I guess.

submitted 4 days ago • 0 comments

The Desmos team increases functionality at a break neck pace. 🤯

submitted 5 days ago • 0 comments

I just submitted my comment. You should too. City Council needs to hear from people who actually want to solve problems (i.e. build housing).

submitted 6 days ago • 1 comment

trump take nest egg

submitted 6 days ago • 4 comments

🚨 San Diego's renown affordable housing program is under threat. The ADU Bonus Program created 115+ affordable homes in just 3 years (compared to 3 homes in the previous 7 years). On Tuesday, City Council votes to begin dismantling it. 🧵/6

submitted 7 days ago • 5 comments

No, this is the most ashamed you've felt as an American *so far*.

submitted 9 days ago • 127 comments

This model reminds me a lot of this video on visualizing 4 dimensions. The premise of the video is that projections onto lower dimensions hide some part of the image. Just like we can distribute the energy between these stacks, so can we distribute how much of each dimension we show in projections!

submitted 10 days ago • 0 comments

did you know air traffic controllers are required to retire in their '50s it is arguably a much higher-stress job than flying an airliner. we hung out with one often in chicago, a friend of a friend, guy was super nice but always moving, talking, thinking a million miles an hour

submitted 10 days ago • 26 comments

There is a YIMBY meeting tonight. And I so badly want to go. But I'm just worn down and my sickness lingers. So here I am at home.

submitted 11 days ago • 0 comments

We only know this man is in Gitmo because Noem tweeted a propaganda photo that included him and his sister saw it. He has no criminal record. He entered the US in January and immediately made an appointment with CBP to claim asylum. They sent him to a concentration camp bc of his basketball tattoo.

submitted 26 days ago • 742 comments

not even highly repressive regimes try to track down every individual protester. you are not trying to leave no signature. that is an unusual signature. you are trying to maximize the mutual entropy of your signature with a person who does not get arrested.

submitted 32 days ago • 16 comments

Contrapositives are for cowards. Instead of saying, "if you do your share of the dishes, we'll have a clean kitchen", they skulk around leaving sticky notes like "if the kitchen's messy, someone didn't do their share." Logically equivalent, but completely lacking in courage.

submitted 47 days ago • 1 comment

A thread on Felix Klein, Emmy Noether, and credit where credit is due. Felix Klein gave a lecture at the Mathematical Society of Göttingen #OTD in 1918. The title was “On Hilbert’s first note on the foundations of physics." 🧪 ⚛️ 👩‍🔬

submitted 46 days ago • 8 comments

I couldn't resist a go at this. A 'proof without words' using just Pythagoras' Theorem. Requires a bit of effort on the part of the reader (as PWWs do) but hopefully kept to a minimum. Wish I had a class actually that could talk through it and articulate the steps. #UKMathsChat #iTeachMaths

submitted 48 days ago • 1 comment

This is almost such an obvious point, it feels slightly crazy to point it out, but a politician winning a national election does not mean that the criticisms of that politician were wrong. Nixon and Bush both go reelected and everything their most unsparing critics said about them was right.

submitted 49 days ago • 164 comments

Does anyone have a proof of the parallelogram identity, with two requirements, no use of inner product and no trigonometry? I would be delighted if anyone has one. I've tried but have not made any headway at finding a proof or devising my own. #MathSky

submitted 49 days ago • 6 comments