Shufflecake ( https://shufflecake.net/ ) is a "spiritual successor" to TrueCrypt/VeraCrypt but vastly improved: works at the block device level, supports any filesystem of choice, can manage many nested layers of secrecy concurrently in read/write, comes with a formal proof of security, and is blazing fast (so much, in fact, that exceeds performances of LUKS/dm-crypt/VeraCrypt in many scenarios, including SSD use).
Disclaimer: it is still a proof of concept, only runs on Linux, has no security audit yet. But there is a prototype for the "Holy Grail" of plausible deniability on the near future roadmap: a fully hidden Linux OS (boots a different Linux distro or Qubes container set depending on the password inserted at boot). Stay tuned!
Have you ever wondered what will happen to those coaxial cables seen in every quantum computer setup, which scale approximately linearly with the number of physical qubits? Multiplexing is not really an option when the qubit waiting for its control signal decoheres in the meantime.
Regarding the coaxial cables, you seem to be an expert, so tell me if I'm wrong, but it seems to me a limitation of current designs (and in particular of superconducting qubits), I don't think there is any fundamental reason why this could not be replaced by a different tech in the future. Plus, the scaling must not need to be infinite, right? Even with current "coaxial cable tech", it "only" needs to scale up to the point of reaching one logical qubit.
https://gagliardoni.net/#20250714_ludd_grandpas
An abstract:
> "but then WHAT is a good measure for QC progress?" [...] you should disregard quantum factorization records.
> The thing is: For cryptanalytic quantum algorithms (Shor, Grover, etc) you need logical/noiseless qubits, because otherwise your computation is constrained [...] With these constraints, you can only factorize numbers like 15, even if your QC becomes 1000x "better" under every other objective metric. So, we are in a situation where even if QC gets steadily better over time, you won't see any of these improvements if you only look at the "factorization record" metric: nothing will happen, until you hit a cliff (e.g., logical qubits become available) and then suddenly scaling up factorization power becomes easier. It's a typical example of non-linear progress in technology (a bit like what happened with LLMs in the last few years) and the risk is that everyone will be caught by surprise. Unfortunately, this paradigm is very different from the traditional, "old-style" cryptanalysis handbook, where people used to size keys according to how fast CPU power had been progressing in the last X years. It's a rooted mindset which is very difficult to change, especially among older-generation cryptography/cybersecurity experts. A better measure of progress (valid for cryptanalysis, which is, anyway, a very minor aspect of why QC are interesting IMHO) would be: how far are we from fully error-corrected and interconnected qubits? [...] in the last 10 or more years, all objective indicators in progress that point to that cliff have been steadily improving
(disclaimer: I am co-inventor at a previous employer, I don't get royalties for it, just reporting)