You think it was primarily poor people who were driving their cars into Midtown?
Readit Newsevanb commented on In New York City, congestion pricing leads to marked drop in pollution e360.yale.edu/digest/new-... · Posted by u/Brajeshwar
I animated these and related 'proofs' some time ago
1/3 = 1/4 + 1/16 + 1/64 + ...
https://evanberkowitz.com/images/2014-03-15-quarters/Triangl...
1/7 = 1/8 + 1/64 + 1/512 + ...
1/8 = 1/9 + 1/81 + 1/729 + ...
evanb commented on AI agents find $4.6M in blockchain smart contract exploits red.anthropic.com/2025/sm... · Posted by u/bpierre
At first I read this as "fined $4.6M", and my first thought "Finally, AI is held accountable for their wrong actions!"
Careful what you wish for. Negating the predicate of "A COMPUTER CAN NEVER BE HELD ACCOUNTABLE. THEREFORE A COMPUTER MUST NEVER MAKE A MANAGEMENT DECISION" might open us up to the consequence.
evanb commented on Using Antigravity for Statistical Physics in JavaScript christopherkrapu.com/blog... · Posted by u/ckrapu
Such a dumb name for an IDE, damn...
I think it's a reference to https://xkcd.com/353/
evanb commented on Tesla sales in Germany have cratered from last year, data shows cnbc.com/2025/11/05/tesla... · Posted by u/moosedman
> Roman salute
Btw, note that it was not actually a Roman salute (though it may have been adopted by Italian fascists because they incorrectly believed it had been used by the Romans; they were keen on Roman iconography).
Indeed, but if I had called it the Nazi salute I'd have been begging the question---or something like it.
evanb commented on Tesla sales in Germany have cratered from last year, data shows cnbc.com/2025/11/05/tesla... · Posted by u/moosedman
> Summary: A dot product is a weighted sum of two vectors.
Nope. This is incorrect. The dot product is a weighted sum of a vector's elements, where the weights are the elements of the other vector. Weighted sum of two vectors would require a third entity to provide the weights.
A dot product is a weighted sum of two vectors, but not in the way the author suggested. The author's use is that one of the vectors is the weights and the other is 'the' vector, so the dot product is the weighted sum of ONE vector. It just so happens that because the author is not interested in the geometric interpretation of the dot product that they forgo the metric.
On the other hand, it is common to need a metric, which is actually the set of weights in the dot product. If `g` is the metric,
dot(a, g, b) = np.einsum('x,xy,y->', np.conj(a), g, b)
evanb commented on Show HN: Strange Attractors blog.shashanktomar.com/po... · Posted by u/shashanktomar
> A small change in the parameter a can lead to vastly different particle trajectories and the overall shape of the attractor. Change this value in the control panel and observe the butterfly effect in action.
I think this is slightly inaccurate. The butterfly effect is about the evolution of two nearby states in phase space into well-separated states. But the parameter a is not a state. To see the butterfly effect by changing a we would need to let the system settle down, give the parameter a small change, and then change it back. The evolution during the changed time acts as a perturbation on states.
Instead, showing that the attractor changes qualitatively as a function of the parameter is more akin to a phase transition.
evanb commented on A laser pointer at 2B FPS [video] youtube.com/watch?v=o4TdH... · Posted by u/thunderbong
As I understand it, this is sort of simulating what it would be like to capture this, by recreating the laser pulse and capturing different phases of it each time, then assembling them; so what is represented in the final composite is not a single pulse of the laser beam.
Would an upgraded version of this that was actually capable of capturing the progress of a single laser pulse through the smoke be a way of getting around the one-way speed of light limitation [0]? It seems like if you could measure the pulse's propagation in one direction, and the other (as measured by when it scatters of the smoke at various positions in both directions), this seems like it would get around it?
But it's been a while since I read an explanation for why we have the one-way limitation in the first place, so I could be forgetting something.
No, you cannot escape the conclusion of the limitations on measuring the one-way speed of light.
While the video doesn't touch on this explicitly, the discussion of the different path lengths around 25:00 in is about the trigonometric effect of the different distances of the beam from the camera. Needing to worry about that is the same grappling with the limitation on the one-way speed.