This article in today’s paper about using human DNA to run computers

<a href=MSNBC News - Breaking News and News Today | Latest News>DNA sparks a computer revolution

contained the following quote:

“They’re also pursuing the idea that genetic material can self-replicate and grow into processors so powerful that they can handle problems too complex for silicon-based computers to solve.”

Sounded kinda familiar, they just left out the “self-reliazation” part.

This is pretty old news. The basics of DNA-based computing were laid out in…96? Something like that.

Back then, researchers were able to use a large batch of DNA to solve a problem in a few hours that would take days on a conventional computer.

The research was interesting, but very impractical. Since then, there have been designs proposed for the building blocks of a DNA-based computer, but I think they’re still pretty cost prohibitive.

Besides, at this point, quantum computation is all the rage, and with good reason: if it takes off, it’ll blow the lid off conventional computers, DNA-based computers, and most realistic sci-fi computers.

Yeah I read something on using dna strands to solve problems. Seemed like a nightmare…however quantum computers are sick. Once they have fully functional quantum computers it will be nutz. I saw a difference in the calulation times of 2 computers that had the same mhz but one was a quantum computer. Well the one computer took something like 100 thousand years to complete the problem and the quantum computer would have done it in less than a second! Yup fast. :slight_smile:

With QC (quantum computation), it gets even better.

In talking about program performance, rather than specify the time it takes as a number of seconds, we specify it as a function of the input size. How exactly input size is measured depends on the problem, so let’s sweep that issue under the rug.

So when talking about a simple program to sort a list of n numbers, we’d say that its running time is n^2. A program to search that same list for a given number has running time n. With me so far?

The problems we look at solving with quantum computation have running times like 2^n, or n! (see the first paragraph of Factorial -- from Wolfram MathWorld for a discussion of what that symbol means).

One such problem that I did a little work on might be interesting to the t-men. Suppose you have a set of exercises, each of which works a given group of muscles. What’s the least number of exercises that you can get away with to hit all the muscles that you’re interested in? It turns out that if you have e exercises, the running time of a program to solve this problem is about 2^e.

Furthermore, if you could find a program that solves this problem significantly faster, you would be instantly famous and you’d win a million dollars. You’d also be more clever than a large percentage of the mathematicians, computer scientists, and other geeks who’ve been working over the last couple years.

The other problems that are that hard relate to much more practical applications, like internet security or file compression.

Anyway, before I forget the point I was making, the exercise problem has a running time of 2^e on a conventional computer. On a quantum computer, it has a running time of e.

Let’s say that the running time corresponds directly to how many seconds it takes. With 30 exercises, you’d need about a billion seconds (roughly 31 years) to solve the problem on a conventional computer. On a quantum computer, you’d need 30 seconds. Throw in another exercise, and the time on the conventional computer goes to over 60 years. On a quantum computer, you need 31 seconds.

That’s why people want these so badly.

The interesting thing is that we’ve been studying QC for almost 20 years now, and in that time, we’ve developed exactly two programs that couldn’t be run on a conventional computer. So it may not be exactly the revolution that we’re looking at, but it’s still pretty cool.

I agree the news isn’t very earth shaking, it was the quote that got my attention. It sounds like the precursor to Skynet (think T2 here), but we’ll find out in about 2029 or so. If my name were John Conner I’d be keeping an eye on these developments.

The Terminator: The Skynet Funding Bill is passed. The system goes on-line August 4th, 1997. Human decisions are removed from strategic defense. Skynet begins to learn at a geometric rate. It becomes self-aware at 2:14 a.m. Eastern time, August 29th. In a panic, they try to pull the plug.