The ultimate Babbage machine was described by K Eric Drexler in his 1987 book "Engines of Creation". This was a "rod logic" device about the size of a bacterium, and Drexler talks about it here: http://www.halcyon.com/nanojbl/NanoConProc/nanocon2.html

to give you an idea of where Drexler thought this could go:

10. Computers from Molecular Mechanical Components These computing devices are smaller than the transistors that were commonly in use in computers a couple of years ago by a factor of 104 in linear dimension, which means 1012 in volume. Thus a device of the capability of a single chip microprocessor, like the Z80 or Motorola 68000 made with 3 micron technology, could be put into a volume of 1/1000th of a cubic micron.

For random access memory, you should get nanosecond access times with 5 cubic nanometers per bit, or allowing for overhead, a density of about 1020 bits per cubic centimeter. That's more information in a cubic centimeter than people have written down since they started making marks on papyrus.

Tape memory gives you another factor of 100 in memory density. Bits would be stored by the presence of a bulky or less bulky side group on a polymer chain, such as polyethylene. To read the tape, you would mechanically probe it to find out how bulky the side group was. The write operation would involve chemical transformation. A reasonable length for such a tape is several microns; a reasonable spooling speed is like a meter per second. To get from one end of the tape to the other is thus a matter of microseconds. We're talking here about tape systems that are far faster than present day hard drives.

Estimates of power dissipation are relatively fuzzy. Making a gigahertz clock assumption and assuming a dissipation of 50kT per bit of a 32-bit word per cycle, we're talking of power dissipation in nanowatts. For a single device in good thermal contact with its environment that's a temperature rise of less than a thousandth of a degree Kelvin.

Thus a large computer can be small on the scale of a mammalian cell, giving some plausibility if you also assume some other hardware and a lot of software development, to the notion of cell repair systems. Also, yesterday I estimated the computational capacity that you could get in one cubic centimeter using this crude mechanical technology - more computational power in a desk top than exists in the world today.

There are a number of papers that discuss this and related topics. If you write to the Foresight Institute [Box 61058, Palo Alto, CA 94306] and send $5, you can get a packet of papers that describes these things in more technical detail. For a donation of $25, you can subscribe to the Foresight Institute newsletter "Foresight Update."

[For more up-to-date information, see the Foresight Institute home page. See also Chapter 12 of Nanosystems.]

So if you have the technology to make wormholes, I suspect making bacterium sized supercomputers wouldn't be a really big deal either. If such a device can be made "self aware" is a different question altogether.

The ultimate Babbage machine was described by K Eric Drexler in his 1987 book "Engines of Creation". This was a "rod logic" device about the size of a bacterium, and Drexler talks about it here: http://www.halcyon.com/nanojbl/NanoConProc/nanocon2.html

to give you an idea of where Drexler thought this could go:

10. Computers from Molecular Mechanical Components These computing devices are smaller than the transistors that were commonly in use in computers a couple of years ago by a factor of 104 in linear dimension, which means 1012 in volume. Thus a device of the capability of a single chip microprocessor, like the Z80 or Motorola 68000 made with 3 micron technology, could be put into a volume of 1/1000th of a cubic micron.

For random access memory, you should get nanosecond access times with 5 cubic nanometers per bit, or allowing for overhead, a density of about 1020 bits per cubic centimeter. That's more information in a cubic centimeter than people have written down since they started making marks on papyrus.

Tape memory gives you another factor of 100 in memory density. Bits would be stored by the presence of a bulky or less bulky side group on a polymer chain, such as polyethylene. To read the tape, you would mechanically probe it to find out how bulky the side group was. The write operation would involve chemical transformation. A reasonable length for such a tape is several microns; a reasonable spooling speed is like a meter per second. To get from one end of the tape to the other is thus a matter of microseconds. We're talking here about tape systems that are far faster than present day hard drives.

Estimates of power dissipation are relatively fuzzy. Making a gigahertz clock assumption and assuming a dissipation of 50kT per bit of a 32-bit word per cycle, we're talking of power dissipation in nanowatts. For a single device in good thermal contact with its environment that's a temperature rise of less than a thousandth of a degree Kelvin.

Thus a large computer can be small on the scale of a mammalian cell, giving some plausibility if you also assume some other hardware and a lot of software development, to the notion of cell repair systems. Also, yesterday I estimated the computational capacity that you could get in one cubic centimeter using this crude mechanical technology - more computational power in a desk top than exists in the world today.

There are a number of papers that discuss this and related topics. If you write to the Foresight Institute [Box 61058, Palo Alto, CA 94306] and send \$5, you can get a packet of papers that describes these things in more technical detail. For a donation of \$25, you can subscribe to the Foresight Institute newsletter "Foresight Update."

[For more up-to-date information, see the Foresight Institute home page. See also Chapter 12 of Nanosystems.]

So if you have the technology to make wormholes, I suspect making bacterium sized supercomputers wouldn't be a really big deal either. If such a device can be made "self aware" is a different question altogether.