[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

*To*: [email protected]*Subject*: Re: Crypto and new computing strategies*From*: [email protected] (FutureNerd Steve Witham)*Date*: Tue, 29 Mar 94 17:09:32 EST*Sender*: [email protected]

> Jim Choate writes: > > > In the latest issue of Scientific American there is an article... On Seth Lloyd's grain-of-salt computer, actually. I didn't know he was going to build one. Anyway, his technique *may* be useful to make quantum computers, but it's more likely to be useful for making regular deterministic massive single-instruction-multiple-data computers out of fairly simple crystals--"maybe even a grain of salt." His technique would make every repeating unit of the 3D crystal into a computing unit. You lose a couple factors of 10 for addressing, making higher-level modules, and error-correction. Still, that's a lot of compute power. Tim May says- > No need to worry just yet. > > There is no convincing evidence that "quantum computers" can calculate > in any way differently from "ordinary" computers. Right. This is just a large power increase using deterministic stuff. It's based on electrons in the shells of atoms in crystals responding to different frequencies of photons depending on their own and neighboring atoms' shells' states. > Devices that are built on a size scale where quantum effects are > important, such as quantum-well devices, don't use QM as a > computational mechanism per se. The devices are just real small. But > not small enough to matter for large RSA moduli--the computations > required to factor a 1000-decimal-digit number swamp even a universe > _made_ of computers! Which is what a naive guess would have said about 129-digit numbers. I would love to see some sort of curve of factoring algorithm efficiencies over time. You could show the log of the difficulty for a selection of number sizes over the past hundred years, say. The experts say it's flattening out and will probably stay that way. A sudden jump in the high end of computer power would mean that we would need to use larger keys sooner than we thought. A key length requiring a little bit more work on the user's part means a lot more work on the cracker's part, but I don't know how many more bits of key compensate for a 10^9 increase in cracking power, say. -fnerd quote me - - - - - - - - - - - - - - - blue pill, Pharm. a pill of blue mass, used as an alterative... alterative, adj. tending to alter... -----BEGIN PGP SIGNATURE----- Version: 2.3a aKxB8nktcBAeQHabQP/d7yhWgpGZBIoIqII8cY9nG55HYHgvt3niQCVAgUBLMs3K ui6XaCZmKH68fOWYYySKAzPkXyfYKnOlzsIjp2tPEot1Q5A3/n54PBKrUDN9tHVz 3Ch466q9EKUuDulTU6OLsilzmRvQJn0EJhzd4pht6hSnC1R3seYNhUYhoJViCcCG sRjLQs4iVVM= =9wqs -----END PGP SIGNATURE-----

**Follow-Ups**:**Re: Crypto and new computing strategies***From:*Jim choate <[email protected]>

**Re: Crypto and new computing strategies***From:*[email protected] (Mike McNally)

- Prev by Date:
**Call setup without warrants?** - Next by Date:
**Re: Ames/ clipper compromised?** - Prev by thread:
**Re: Crypto and new computing strategies** - Next by thread:
**Re: Crypto and new computing strategies** - Index(es):