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tooltower

642 karma · joined November 9, 2020

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tooltower··on Making RAM at Home [video]
https://en.wikipedia.org/wiki/Dynamic_random-access_memory#P...

It turns out they intentionally drain a bit of the storage capacitor, and amplify that weak signal. Some of that amplified charge is then fed back to storage.

tooltower··on What are skiplists good for?
In my personal projects, I've used it to insert/delete transactions in a ledger. I wanted to be able to update/query the account balance fast. Like the article says, "fold operations".
tooltower··on We can't have nice things because of AI scrapers
> Rather than downloading our dataset in one complete download, they insist on loading all of MusicBrainz one page at a time.

Is there a standard mechanism for batch-downloading a public site? I'm not too familiar with crawlers these days.

tooltower··on Zero knowlege proof of compositeness
Are we sure that the base reveals nothing about the factors if n is composite? I have never seen a proof of that.

Usually, zero knowledge proofs also require a prover who knows the answer (the factors in this case). This is just a primality test that can be performed locally.

tooltower··on Why is hash(-1) == hash(-2) in Python?
This article is not about the API contract of the hash function, or the abstraction it provides. If you are just trying to hash things, you don't need any info here.

It's very much trying to go _under_ the abstraction layer to investigate its behavior. Because it's interesting.

This is very similar to how people investigate performance quirks or security issues.

tooltower··on GenChess
I still don't see the settings. Can anyone help?
tooltower··on Google’s TOS doesn’t eliminate a user’s Fourth Amendment rights, judge rules [pdf]
The hash functions used for these purposes are usually not cryptographic hashes. They are "perceptual hashes" that allows for approximate matches (e.g. if the image has been scaled or brightness-adjusted). https://en.wikipedia.org/wiki/Perceptual_hashing

These hashes are not collision-resistant.

tooltower··on LHC experiments at CERN observe quantum entanglement at the highest energy yet
Kind of? Keep aside quantum mechanics for a second. In any classical experiment that has random outcomes, would you say that the probability distribution is a property of a single system or a bunch?

You can only deduce a distribution from repeated measurements. But most physicists would have no problem talking about a single experiment having many possible outcomes, governed by a probability distribution. It's almost a philosophical question about whether probability means anything in single systems.

It's the same way in quantum mechanics. The effects of entanglement can only be discerned if you take repeated samples. But we still feel okay talking about single systems governed by such entanglement.

tooltower··on LHC experiments at CERN observe quantum entanglement at the highest energy yet
> How can entangled system be differentiated from a nonentangled system?

The canonical answer to your question is Bell's inequality: https://en.wikipedia.org/wiki/Bell's_theorem. But TL;DR: the distinction only shows up in the statistics of repeated experiments. There is _no way_ to distinguish them in single-fire experiments. Entanglement is defined in terms of "odd" statistics.

In repeated measurements of related properties (e.g. spin along varying angle), entangled systems show more correlation than it should be possible classically.

tooltower··on Chain of Thought empowers transformers to solve inherently serial problems
Constant depth circuits can solve everything? I feel like I missed some important part of circuit complexity. Or this is BS.
tooltower··on CrowdStrike ex-employees: 'Quality control was not part of our process'
This is like online reviews. If you selectively take positive or negative reviews and somehow censor the rest, the reviews are worthless. Yet, if you report on all the ones you find, it's still useful.

Yes, I'm more likely to leave reviews if I'm unsatisfied. Yes, people are more likely to leave CS if they were unhappy. Biased data, but still useful data.

tooltower··on "Firefox added [ad tracking] and has already turned it on without asking you"
I have been donating a few hundred dollars to Mozilla every year (or at least most years) for the last 7 years. It's not much, but I might stop that donation now.
tooltower··on Safer roundabouts are replacing traffic signals (2023)
I didn't get from the article: are they better than all traffic signals, or signals with unprotected left turns? And what's a good vs. bad turnabout like?

I have had to go through a few that feel extremely dangerous compared to having all cars stop for me. So I know I must be missing something.

Edit: Also, I see a lot of comments on yield. I'm probably confused too, but how do they work when traffic is non-stop? Is there a specific traffic rate beyond which roundabouts become less safe?

tooltower··on "Firefox added [ad tracking] and has already turned it on without asking you"
I just found this setting in mobile, but I don't know if it's the same feature: Settings > Data Collection > Marketing
tooltower··on A reawakening of systems programming meetups
I'm interested in attending these in my area (SF South Bay). How should we discover similar meetups?

Is there a place we should subscribe to?

tooltower··on Text for Proofing Fonts (2020)
This reminds me of the difference between micro-benchmarks vs real programs. I would always include extracts from real texts of a few different types (novels, lists, technical writing, short paragraphs like in a playscript). But a test text like these are also helpful in exercising a few rare cases, like z, q, and certain ligatures.
tooltower··on Night-vision lenses so thin and light that we can all see in the dark
Thanks for the actual paper they published
tooltower··on Framework Laptop EC Driver Being Prepared for Linux
I'm not OP, but I had no idea KDE had that built in. I'll have to check for something analogous in my xfce config when I'm back at my laptop. Thanks!
tooltower··on CBMC: C bounded model checker (2021)
> [...] other algorithms may require the sort of induction one gets with constructive proofs to sufficiently verify. There is an art to this which will lead to style changes in C and a slightly different way of building up functions from pieces that can be trivially model checked.

Is there a book or article that talks more about this? I.e. how to write code in a way that is more amenable to model-checking (bounded or otherwise)?

tooltower··on Frawk: An efficient Awk-like programming language. (2021)
What's the common tool people use these days for manipulating json in an awk-like manner?
tooltower··on Roku says hackers gained access to 576k accounts in latest data-breach incident
Even the CDs these days will often refuse to play without an internet connection.
tooltower··on S.3819 – Shrinkflation Prevention Act of 2024
It might vary from state to state. Here in California it's pretty inconsistent. Anecdotally, in Virginia it was almost always there for every product.
tooltower··on A 1.9 solar mass neutron star candidate in a 2-year orbit
For one, it's really close to the upper end of how massive a neutron star can be. https://en.wikipedia.org/wiki/Tolman%E2%80%93Oppenheimer%E2%... says the limit is around 2.01 to 2.17 solar masses.
tooltower··on How much bigger could Earth be before rockets wouldn't work?
The idea is that you can pick up cargo, fuel, and rocket-building minerals directly from Mars.
tooltower··on Amazon and iRobot call off their planned acquisition
I haven't kept up in recent years. Who are the better competitors these days?
tooltower··on The bane of my existence: Supporting both async and sync code in Rust
The comment threads here discuss async in many different languages: Rust, Go, JavaScript, Python. Can somebody knowledgeable describe how they are subtly different between languages? Why are they painful in some but not in others?

Is there already an article that describes this well?

tooltower··on Solver Performance: 1989 vs. 2024
The latter. The real-world instances are not uniformly distributed across the language. It is pretty easy to randomly generate problems that are hard for current solvers.

Caveats:

* "uniform distribution" is a tricky concept over infinite countable sets. Famously, it doesn't exist. You have to restrict the length or something.

* I have no idea if there's a concrete result linking Kolmogorov complexity and solving ease. I suspect no, since even a complex but known problem can be solved rather quickly by special-casing.

tooltower··on Making a font
Speaking of fontforge, does anyone know how to preview a few paragraphs of text in a font as it's being designed?

A single sentence with a quick brown fox is often not enough.

tooltower··on Publishing my first game using PICO-8
Does anyone know of an open-source version of PICO-8? I don't even care about any of the features, as long as there's an active community around the project.
tooltower··on Conferences are inadvertently excluding many attendees from foreign countries
Visa type is also a factor. F1 and H1B frequently get capped to just 1 year.
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