Hacker News: gregdeon

New comment by gregdeon in "Artemis II Launch Day Updates"

gregdeon — Wed, 01 Apr 2026 23:27:19 +0000

I suspect that they might have switched away from the booster separation on purpose. That's probably a risky moment of the launch, and they may have wanted to avoid televising a disaster like in the Challenger launch.

Aside from that, agreed that the camera work was awful.

New comment by gregdeon in "2% of ICML papers desk rejected because the authors used LLM in their reviews"

gregdeon — Thu, 19 Mar 2026 18:05:35 +0000

The conference organizers are very much aware of this possibility. Prompt injection for the sake of getting a positive review is explicitly banned.

New comment by gregdeon in "Closure of the Weatheradio service in Canada"

gregdeon — Tue, 03 Mar 2026 03:05:08 +0000

Canadian checking in!

New comment by gregdeon in "British Columbia is permanently adopting daylight time"

gregdeon — Tue, 03 Mar 2026 02:52:53 +0000

> Unless you roll out of bed and instantly onto your commute, you're getting natural sunlight through all your windows for hours every morning.

Sadly, not if you're a student living in a basement in Vancouver!

New comment by gregdeon in "Fix the iOS keyboard before the timer hits zero or I'm switching back to Android"

gregdeon — Sat, 14 Feb 2026 03:17:24 +0000

Same here. If you shouldn't design for the average dimensions, what _should_ you design for?

New comment by gregdeon in "Advent of Code 2025"

gregdeon — Sun, 30 Nov 2025 19:15:32 +0000

Oof. I had a great time cracking the top 100 of Advent of Code back in 2020. Bittersweet to know that I got in while it was still a fun challenge for humans.

New comment by gregdeon in "I mathematically proved the best "Guess Who?" strategy [video]"

gregdeon — Sat, 29 Nov 2025 15:37:09 +0000

This is all right, but it just kicks the intuition into the assumption that the function is convex. As far as I can tell from the paper, this turns out to be exactly the argument they use to prove that (1/2, 1/2) is the optimal guess. But the majority of that proof is dedicated to showing that the function is indeed convex.

New comment by gregdeon in "I mathematically proved the best "Guess Who?" strategy [video]"

gregdeon — Sat, 29 Nov 2025 02:56:25 +0000

Sure, I think it makes intuitive sense to me that you should play riskier when you're behind. The surprising part to me is that when you're ahead, even if you know that your opponent will play "sub-optimally", that doesn't change your own optimal move.

New comment by gregdeon in "I mathematically proved the best "Guess Who?" strategy [video]"

gregdeon — Sat, 29 Nov 2025 02:52:56 +0000

I know that it minimizes the expected number of moves. But, the goal is to maximize the probability that you win in fewer moves than your opponent, not minimize the expected number of moves. Given that your opponent is playing some riskier strategy, it's not intuitively obvious to me that your optimal moves for those two objectives are the same.

New comment by gregdeon in "I mathematically proved the best "Guess Who?" strategy [video]"

gregdeon — Sat, 29 Nov 2025 00:32:20 +0000

I find it somewhat surprising that the optimal play when you're ahead is still just binary search. Is there an intuitive reason why it's not productive to make riskier guesses? Why not use my lead to have some chance of sealing my victory immediately, while still maintaining my lead if I'm wrong?

New comment by gregdeon in "Project Euler"

gregdeon — Wed, 12 Nov 2025 20:26:29 +0000

Wow. You reminded me of a computer engineering class years ago where we wrote assemblers and emulators for a simple architecture. I tested mine by writing a solution for one of the first Project Euler questions!

New comment by gregdeon in "I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours"

gregdeon — Tue, 11 Nov 2025 23:06:29 +0000

I wonder if it would show up on the heart rate (or heart rate variability) tracking from an Apple Watch or similar. My Garmin picks up stressful events all the time.

New comment by gregdeon in "Some people can't see mental images"

gregdeon — Fri, 31 Oct 2025 00:02:01 +0000

It always blows my mind how universal this experience was for people around my age. Mine was a bouncing ball...

New comment by gregdeon in "Bad Apple but it's played inside Super Mario Bros"

gregdeon — Wed, 01 Oct 2025 07:18:04 +0000

Incredible work! I recently gave a talk about TASing to an audience of CS grad students, and of course I had to mention your SMB3 runs. Your videos are phenomenal at making this stuff accessible outside of hardcore gaming circles.

New comment by gregdeon in "Bad Apple but it's played inside Super Mario Bros"

gregdeon — Tue, 30 Sep 2025 03:31:17 +0000

The entire TAS file takes about 16 MB, far more than the 4 KB of RAM on the NES. During the audio + video playback, the TAS is streaming via the controller by making inputs roughly 500 times per frame (15 kHz).

New comment by gregdeon in "No reachable chess position with more than 218 moves"

gregdeon — Fri, 26 Sep 2025 15:20:16 +0000

I'm not sure about Gurobi or how the author used it in this case. But in general, yes: these combinatorial solvers construct proof trees showing that, no matter how you assign the variables, you can't find a better solution. In simpler cases you can literally inspect the proof tree and check how it's reached a contradiction. I imagine the proof tree from this article would be an obscenely large object, but in principle you could inspect it here too.

New comment by gregdeon in "How inaccurate are Nintendo's official emulators? [video]"

gregdeon — Mon, 08 Sep 2025 14:57:41 +0000

What a pioneer. RIP Byuu.

New comment by gregdeon in "ICPC 2025 World Finals Results"

gregdeon — Fri, 05 Sep 2025 02:10:27 +0000

Wow, incredibly interesting to see what one of these manuals looks like! Thanks for sharing.

New comment by gregdeon in "Faking a JPEG"

gregdeon — Sat, 12 Jul 2025 02:16:28 +0000

Yes: the reason why some data can be compressed is because many of its bits are predictable, meaning that it has low entropy per bit.

New comment by gregdeon in "John Carmack talk at Upper Bound 2025"

gregdeon — Fri, 23 May 2025 16:12:07 +0000

I think it is. Latency was just one of the problems he described. A physical controller sometimes adds "phantom inputs" as the joystick transitions between two inputs. Physical actuators also slow down with wear. A physical Atari-playing robot needs to learn qualitatively different strategies that are somewhat more robust to these problems. Emulators also let the bot take as much time as it needs between frames, which is much easier than playing in real time. To me, all of this makes a physical robot seem like a decent way to start engaging with problems that come up in robotics but not simulated games.