I love my city youtu.be/uttoyAX4ntc?...

The impact of Alfred Menezes in cryptography is profound. Francisco RH and I are organizing an afternoon session in Latincrypt to celebrate Alfred's career: menezesfest.info If you're coming to Medellín, consider attending!

Always bothers me when you lose the 1/N factor in a multi-user security proof. Was thinking about how to dodge it; consider this for Schnorr signatures: you are an active adversary against a single challenger, with access to a multi-user adversary.

I wrote a bit about options for phones at protests, explaining the benefits and drawbacks, and added some security tips at the end.

Ursula K. LeGuin on technology

An out-of-schedule update to my quantum landscape chart: sam-jaques.appspot.com/quantum_land..., prompted by @craiggidney.bsky.social 's new paper: arxiv.org/abs/2505.15917. A startling jump (20x) in how easy quantum factoring can be! Also: much improved web design!

Seriously embarrassed myself in front of my cat: Middle of the night, cat sits there wanting pets. I can't see a thing, I reach out and try to pet a dirty pair of shorts.

I'm often asked if I'll redo the 2019 quantum factoring estimate. Denser storage by yokes, smaller magic factories by cultivation, slimmer approx arithmetic by Chevignard et al… surely the cost is lower now? Yes, it's lower now. security.googleblog.com/2025/05/trac... arxiv.org/abs/2505.15917

Almost all good points. I also see too much tendency to conflate moral skepticism of AI (i.e., that AI is doing a lot of harm) with technical skepticism (i.e., that AI is not useful or powerful)

Dang, AI is really making the Internet suck

"If you want to prompt ChatGPT 40 times, you can just stop your shower 1 second early." "If I choose not to take a flight to Europe, I save 3,500,000 ChatGPT searches. this is like stopping more than 7 people from searching ChatGPT for their entire lives."

My biggest threat model for my online accounts is that I will be in another place, with the wrong sim, or my phone falls in the ocean, and I will need access to an absolutely essential piece of documentation. Single-factor authentication saves me.

I actually learned an embarrassing amount from this episode securitycryptographywhatever.com/2025/03/23/p...

On the anniversary of the sinking of the Titanic, we thought we'd answer a question that's often asked, "If they raised the Mary Rose, why not raise the Titanic?" Allow our scaled diagram to explain...

I think cities should red team their building codes and hire a contractor to build the most unhinged home that is technically up to code

Spooky thought: most job markets implicitly assume there are at least as many entry level jobs as senior jobs, so that people can get the experience they need to do the senior jobs. But if you can cheaply replace the entry level workers with AI, the balance could flip

Had a student on a project to do some simulation analysis of errors in Shors algorithm but we hit this problem: how do you even know when things went right, if random noise can factor just as well?

uh oh

Here's an argument against area-time cost, and instead for total operation cost: if large portions of a computer are idle during an algorithm, they could just be programmed to mine cryptocurrency instead, to recover costs for the attacker

Great article! Had no idea how insanely readable COBOL code was until now. Let alone the gendered/gatekeeping dynamics behind its historical denigration or modern downplaying of the number of active coders…

This jibes with contemporary reporting that the raids hit several residential buildings, in each case killing about 15 people and wounding more. Maybe a little more of the conversation should be about how cavalier we apparently are about bombing civilian homes? www.aljazeera.com/news/2025/3/...

If Trump+Musk have taught us anything, it's that all press is good press. I fully expect these events to be good for Signal adoption long-term.

Opsec level: underfunded provincial museum

Suddenly struck with a cursed analogy for memory management: a bunch of blind alien roommates sharing a fridge. Waterloo CS students are lucky I only teach math courses!

If you discover a major security vulnerability in some company's software, and you short the company's stock before revealing the vulnerability, is that insider trading? (purely hypothetical!)

Unironically I kind of think "everything is an op" is an op

2024 update for my chart on the landscape of quantum computing: sam-jaques.appspot.com/quantum_land... Not much visible on the chart, but Google's result (the one with the recent press attention) is a pretty big deal

Props to Google for putting their RCS result at the absolute bottom of the "usefulness" axis:

Discussion Q: is post-compromise security actually useful? I can't imagine my device being seized by anyone who is sophisticated enough to clone its state and continue to intercept messages, but not sophisticated enough to replace my messaging app with a backdoored look-alike

Cryptographers last week:

I'm irrationally angry at the Amazon reviews complaining that their high density, high speed USB drives get too hot when they use them

Huge quantum computing news! Surface codes below threshold, distance 7, and below break even! arxiv.org/abs/2408.13687