Hacker News: tromp

New comment by tromp in "I Don't Have a Smartphone"

tromp — Wed, 02 Sep 2026 20:21:45 +0000

> I still keep in a drawer an old OnePlus 5 I bought in 2017 with a pristine Android system.

How pristine is that when the last supported Android version is 10?

> This phone is sometimes necessary. Like when a known bug in /e/OS prevented my banking app from working for several months.

This surprises me. Until very recently I was using a phone I bought in 2017, which similarly supports no Android beyond version 10.

Since early this year, my bank app started insisting that I upgrade my Android to 11 or higher, and hence stopped working.

More recently, Gmail also started insisting I upgrade Android. As a result I had to get a new phone, which in many ways is worse than my old phone (still 7.2" but worse aspect ratio, no more full fingerprint sensor and much worse battery life).

So the idea of keeping an old phone around in order to bank seems rather odd to me.

New comment by tromp in "Commodore 64 released September 1, 1982"

tromp — Wed, 02 Sep 2026 12:05:17 +0000

Make that 44...

New comment by tromp in "Recover a Bitcoin private key from its public key, in the browser"

tromp — Wed, 26 Aug 2026 06:50:25 +0000

You may have missed this part:

> What this does not show

> The attack above depends on conditions that ordinary Bitcoin keys do not meet.

> Ordinary Bitcoin keys are not affected by any of this

> A properly generated private key is spread across roughly 2 to the power of 256 possibilities. The square root of that is 2 to the power of 128, which is not attackable by anyone, with any budget, ever.

New comment by tromp in "λλ: A Programming Language for Silicon Photonics"

tromp — Wed, 19 Aug 2026 14:58:24 +0000

That also sounds like a good french name for Binary Lamda Calculus.

New comment by tromp in "λλ: A Programming Language for Silicon Photonics"

tromp — Wed, 19 Aug 2026 08:41:24 +0000

Note that this is not an extension of the pure λ-calculus.

Abstraction (λx.e) and application (f a) are missing, although the let construct "let x = e1 in e2" is equivalent to their combination ((λx.e2) e1).

The paper has few details on the higher-level specification language in which users specify desired behaviour:

> Specification Language. Specifications are written as relations between input and output ports, expressed using linear expressions. On their own, specifications are not λ _λ programs. It is the job of the synthesizer to find λ _λ programs that realize a given specification. For example, a simple switching behavior can be specified as output[i] = input[j], while a 2x2 AllReduce operation can be written as output[1] = (input[1] + input[2])/sqrt(2) and output[2]= (input[1] - input[2])/sqrt(2).

New comment by tromp in "λλ: A Programming Language for Silicon Photonics"

tromp — Wed, 19 Aug 2026 08:24:30 +0000

The second λ is subscripted. As footnote 1 in the paper says:

> Pronounced “lambda lambda”. One λ refers to the λ-calculus and the other refers to an optical wavelength.

New comment by tromp in "How to put 170 atoms in an atom"

tromp — Mon, 17 Aug 2026 15:41:21 +0000

> So in 2018, an international team of scientists created a BEC out of strontium atoms, and hit one of those atoms with a carefully tuned laser, exciting its outermost electron and turning it into a Rydberg atom. Several other atoms from the BEC were caught within between that outer electron’s inflated orbital.

This is not so much putting 170 atoms in one, but inflating one beyond the size of its 170-atom neighbourhood.

The hard part being to cool the neighbourhood to such an extremely low temperature that the inflated atom doesn't ionize.

New comment by tromp in "The Dutch community where people live on strips of land in a lake"

tromp — Sat, 15 Aug 2026 19:01:46 +0000

You may find this area on google maps at https://www.google.com/maps/@52.1792241,5.0288801,516m

New comment by tromp in "Count Binface receives over a quarter of votes in Clacton by-election"

tromp — Fri, 14 Aug 2026 17:48:56 +0000

> Binface received 26.9% of the vote

> That's why Count Binface has been able to stand in so many high-profile elections. He has, however, lost his £500 every time, after failing to meet the minimum 5% of votes cast in order for his deposit to be returned.

It would seem he didn't lose his £500 this time...

New comment by tromp in "The lattice of sets of natural numbers is rich (2021)"

tromp — Thu, 13 Aug 2026 13:20:00 +0000

TREE(3) is also unimaginably tiny compared to the normal form size of (λa.aaa(λbλcλdλe.ebbbcde)aaaa)(λfλx.f(fx)) [1].

[1] https://wiki.bbchallenge.org/wiki/Lambda_Calculus#Champions

New comment by tromp in "Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone"

tromp — Sun, 09 Aug 2026 21:32:31 +0000

His dyneema driven drum is eerily similar to the dyneema driven drum (called "snek") https://rowingbike.com/nl/model/thys-222-revolver#content-7 on the Thys rowingbike https://rowingbike.com/nl/model/thys-222-revolver

New comment by tromp in "How real are real numbers? (2004)"

tromp — Mon, 27 Jul 2026 20:46:02 +0000

> You can easily demonstrate it [half an inch] as the ratio between one inch and two feet, compared to the reference ratio between one inch and one foot.

You seem to have your units confused. Half an inch is a distance, while ratios, or comparisons of ratios, are all dimensionless scalars.

New comment by tromp in "GM Backs Sodium Ion Batteries for U.S. Grid Storage"

tromp — Sun, 26 Jul 2026 07:00:56 +0000

> Sodium Ion can go to 10,000 cycles (27 years) with a 70% capacity reduction at that life.

The article claims much better:

> the company’s GS1.1 [Sodium Ion] system will store energy for 20 years, over roughly 20,000 cycles, and still retain 80 percent of its capacity. For LFP, a basic durability benchmark pegs them at 70 percent capacity after 8,000 cycles.

New comment by tromp in "Making ASCII Art in Vim"

tromp — Thu, 23 Jul 2026 15:09:34 +0000

> When asked, "do you need any special programs or software to make ASCII Art?", the great ASCII artist Joan G. Stark said: "All you need is a text editor with a fixed-width font."

You can find her impressive ASCII art archived at

https://web.archive.org/web/20091028031724/http://www.geocit...

New comment by tromp in "Computation as a universal and fundamental concept"

tromp — Fri, 10 Jul 2026 17:50:13 +0000

It can be solved if the memory is bounded. But unbounded memory comes with undecidable problems.

The PocketMage E Ink digital assistant

tromp — Fri, 10 Jul 2026 09:58:44 +0000

Article URL: https://www.engadget.com/2211733/pocketmage-e-ink-digital-assistant-that-absolutely-obsessed-with-wizards/

Comments URL: https://news.ycombinator.com/item?id=48857908

Points: 1

# Comments: 0

New comment by tromp in "Captcha proves you're human. HATCHA proves you're not"

tromp — Fri, 26 Jun 2026 12:39:32 +0000

This is like Proof-of-Work, but for an extremely small amount of work, that would already overwhelm human effort, like computing a single SHA256.

New comment by tromp in "What are peoples' biggest issues with Crypto?"

tromp — Thu, 25 Jun 2026 10:17:24 +0000

Every single cryptocurrency (except one or two) concentrates wealth on the founders and early adopters.

New comment by tromp in "Europe's housing shortages are worse than America's"

tromp — Tue, 23 Jun 2026 15:37:56 +0000

> In France, Germany, Austria, Switzerland, the Low Countries, Ireland and Scandinavia, however

What are the Low Countries? Is that a mis-translation of the Netherlands?

New comment by tromp in "Subterranean fungi networks more than 100 quadrillion km in length"

tromp — Wed, 17 Jun 2026 14:51:28 +0000

Meanwhile, a single human cell's DNA stretches for about 2 meter, one human's DNA stretches for about 2 x 5.4 trillion meter, and all living human DNA for a whopping 8.6 x 10^22 meters, nearly a thousand times longer than the fungi networks...

[1] https://www.reddit.com/r/theydidthemath/comments/1gfq6k2/how...