Cryptographer swaps algorithms for the freezing crypt
Speaker's Corner Ralph Merkle
THE STRANGER a new idea is, Ralph Merkle says, the more people resist it – and the more he thinks it's worth researching. Merkle's first strange idea was for a mechanism by which strangers could agree on a cryptographic key to encrypt data in real time. His 1974 paper outlining this was rejected for five years.
"That told me it was not a well understood or accepted idea," he says. "His favourite: the publisher who said the paper didn't fit in with "mainstream thinking". Eventually, Merkle found Martin Hellman, with whom he shares patents and who, in 1979, published with Whitfield Diffie the paper that launched public key cryptography, now in everyday use.
That Merkle's first crazy idea is now mainstream makes it harder to dismiss his current crazy ideas.
After finishing his PhD at Stanford in 1979, Merkle went on to work in the San Francisco Bay Area: a Canadian telco, a startup, Xerox's famed PARC labs. He got married, and bought a house. "And I began to look ahead." Barring obstacles the decades ahead looked OK.
But extend far enough and, "People die. I decided this wasn't an optimal state of affairs, and given the astonishing advances of modern science and technology, is there some way of dealing with this problem?"
He began researching life extension: vitamins, exercise, early diagnosis. And then he came across cryonics. "I didn't think much of it at first, but when I began to analyse it I realised that indeed it should work."
Freezing in itself is not the problem: "At the temperature of liquid nitrogen you can preserve tissue for centuries, or even millennia." The problem – and the locus of controversy – is advancing medical technology sufficiently to revive people and cure them of whatever killed them. It's that problem that led Merkle to nanotechnology and, more precisely, molecular manufacturing. The idea of being able to build tiny robots at the molecular level goes back to a 1959 lecture by the the ultra-respectable Richard P. Feynmann, but it's been controversial ever since Eric Drexler published his 1986 book Engines of Creation.
"I read it shortly after it came out," says Merkle, "and I concluded that it was obviously true. If you read Feynmann's talk, it's clear that the intuition of a physicist with an excellent reputation for good intuition was that molecular manufacturing was feasible and would develop. There have been no real arguments against it – although at the same time one sees a number of people rather incoherently resisting it."
Merkle's efforts are concentrated on describing the tools that will be needed at the molecular level; a recent paper he wrote with Rob Freitas considers diamond mechanosynthesis. "We should be able to bring to the molecular level the same kinds of techniques used at the scale of us: hands pick up and assemble parts." The paper therefore describes a set of nine molecular tools and basic structures and how they might be built out of diamond, fullerenes, graphite, and germanium (needed to help chemical reactions). "It's laying out the road map. Describing what we're going to build, the steps of how to get there, how the tools react with the surface, how you build structures. As we make it clearer we will have a widening community of people who say they get it."
The technical problems aren't the key point. "The key issues deal with humans and human understanding of what is going on."
Which comes back to the question of getting people to think seriously about new ideas. Public key cryptography was easier: there was just a single barrier idea (that keys have to be secret) to get past. With nanotechnology, there are many many small barriers that add up to a very large one. The more complicated the idea the more emotions kick in.
The problem extends to scientific publishing and funding, which are done by committee. "Committees are very good when dealing with an accepted body of ideas and they're looking at incremental research." µ