[Worldbuilding] Divergent, retro and other 'not of this world' Computers and Software

[Anaraxes]

For a setting with analog computers, you're going to want some doubletalk dealing with problems in error control and propagation. (If you're the sort to worry about such things, that is; otherwise, just blast off and show the Overlord of Jupiter a thing or two.) All of the input to an analog computer is valid, and produces variations in the output. One of the virtues-from-necessity of digital logic is that it tolerances a lot of variance in the input, as ultimately it has to be a "0" or "1". There's no such thing as a 0.001 or 0.01 to worry about.

Another advantage was of course simply miniaturization, transistors to ICs. We happened to figure out how to make tiny digital logic circuits cheaply, so they could be employed in massive numbers. We still don't know how to make tiny gears and cams. The alternate tech setting could either settle for less complexity in the computers, or some more handwavium.

The third advantage that comes to mind is ease of reprogrammability. This doesn't matter for computers dedicated to one job, like fire control on WWII battleships. But it's vital if you have general-purpose computers so "there's an app for that". Sculpting custom cams for each equation in every problem won't scale well. So you might invent something programmable, or have massive computers with lots of special execution units, or perhaps some T-1000 liquid metal will come in handy.

[panton41]

Keep in mind there were (and are) chip-based analog computers so it's not just gears and cams and vacuum tubes. The F-16A and F-14A had chip-based analog computers (both mated with digital computers) and the SID chip (sound chip) on the Commodore 64 included analog circuits. All analog really means in that the input and processing is based on a curved waveform rather than on-off.

For that matter "fuzzy logic" is an attempt to bring to digital computing some of the abilities of analog computers. Varying levels of "maybe" are useful in lots of places.

[Anaraxes]

Originally Posted by ciaran_skye

Keep in mind there were (and are) chip-based analog computers.

Yes. Nothing like the density of digital circuits, and there are some issues with precision of the component values (capacitance, resistance, etc) as well as range. But it's possible to have integrated analog circuits. It's also common to have a few analog components on a chip with mostly digital logic.

For another example, radar systems often used analog memories to store incoming waveforms at radar frequencies and play those back (to jam the original signal, for instance, or control something else related to that signal). Only relatively recently have digital electronics been fast enough and large enough to capture signals at the multi-gigahertz frequencies needed for ECM.

[johndallman]

Originally Posted by Anaraxes

We still don't know how to make tiny gears and cams.

We're making real progress on that. Making the parts is fairly easy with mask-and-etch techniques derives from integrated circuit fabrication. I get the impression that assembling them into large systems may be harder.

[vicky_molokh]

Mathseer

A Mathseer is an analogue of computers for a magical setting of some sort. It is an enchanted device that, as the name implies, precognitive in the mathematical field. Here's how it works:

The operator sits behind a mathseer and visualises a mathematical problem that needs solving. The problem can be extremely complex, taking centuries to solve; however, the operator must be capable of solving it, even if it would require an abacus and enormous amounts of ink and paper.

As the operator visualises the first steps of a solution, the mathseer forges a temporary bond with the operator's spirit. Through this link, it provides insights into the answers to the next step. There is a positive feedback loop, and the longer the operator works on a problem, the further into the future the mathseer can look, and the faster it can provide the next step - even many times faster than normal people can think.

Game mechanically, a mathseer gives its use Intuitive Mathematician, as well as a limited form of Enhanced Time Sense that can only be used for interfacing purposes.

[Luke Bunyip]

How about a TL4 computer which is an entire building, full of clerks and mathematicians. This in turn is linked via a semaphore network to other cities, and their computational centres.
Read it in an obscure Australian Sci Fi book. Peddle powered trains, librarians dueling with matchlock pistols, AND a scaled up 'computer'.