Consolidation Earth
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It took a significant amount of work to re-engineer my high-vacuum chamber and ancillary equipment to accommodate both the existing devices and a newly acquired SEM, while giving all of them targeting access to the existing mobile sample stage upon which the nanoscale device under construction - at least, attempted construction - was mounted. Of course, this also required additional funds and, as is often the case in a university environment, the acquisition of those funds took longer than the actual work itself. Grant applications and evaluation forms and peer reviews: such is the life of the professional academic. Scanning Electron Microscopes are famous for being able to provide fabulously detailed pictures of truly tiny objects: microscopic insects, grains of pollen, bacteria and viruses are the standard examples used. What is less well known is that they have a significant trade-off between the resolution of the image they provide and the time taken to capture that picture. Even with the most modern examples, a grainy, noisy moving feed at a few frames per second might be possible under ideal conditions: enough to be able to pan around and zoom in on a likely-looking feature. Once locked in, it might take more than a minute to capture at much higher resolution the kind of detailed picture you might expect, with any blurriness caused by the subject moving, which it would only do if you had done a bad job of sample mounting. Finally, I was ready for a first trial. First, I progressed the build through many steps until I reached the one just before the step which always failed, confirming in the usual way that the build had gone correctly. Then I brought the SEM online, scrolling up and down while squinting at flickering fuzzy images on the computer screen until I found the half-formed nanodevice I was making and got it centred in the field of view. The device under construction looked good, and I pressed the button for a full-resolution scan, which took a little over a minute - although it felt like much longer - and produced a beautifully detailed image. Then I turned the SEM off; I did not want the electron beams to interfere with one another. The microscope beam is relatively low power, so that it does not move around the molecules of the object being imaged, thus breaking it. On the other hand, the assembly beam actively wants to move molecules to new positions and is therefore much more powerful. I had decided to run the next assembly operation until about half complete and then take another look with the microscope. Through the flicker and noise, I re-centred the image; the device looked pretty much exactly as I had expected, so I concluded that whatever the failure mode was had not yet occurred. I was just about to turn off the SEM and restart the construction when I glimpsed something moving, some distance from the device. Something was emerging from the gold foil which formed the work surface, rising up like some hunting sea creature shrugging off the seabed sand which had camouflaged it until moments ago. Whatever it was, it had an ellipsoid body with a spherical head at one end and moved across the worksurface using neither legs nor wheels but some kind of articulated toothed sprockets which adhered to the surface. Whatever it was, it crawled its way over to where my half-finished device stood quiescent and then started to climb, the same sprocket wheels extending more and longer teeth for extra grip. It reached the section I was in the process of assembling. It froze, apparently studying what I could only think of as its target. I dragged my attention away from the screen for a moment and pressed the button which started the high-resolution scan, just in time to capture the thing's head split open and whatever was inside starting to dissolve my newly created component. The device's head was dissolving too, whatever engineered macromolecules within tearing apart both itself and its target. It was clear that the ellipsoid nanodevice must be one of billions, trillions, no, nonillions of such things - as numerous as viruses, at least - which infests every part of our world; otherwise it would be statistically infeasible that one just happened to be within a fraction of a micron of the device I was trying to make in my vacuum chamber. As a scientist, my reactions were torn: on the one hand, it was a beautifully articulated device, perhaps half the size of a typical virus, a masterpiece of nanoscale engineering: flexible, probably self-replicating in a way that even viruses cannot manage without coopting the biochemical engine of a much more complex organism - cells of one kind or another. On the other hand, I felt genuine visceral horror at the thought that these devices, or something like them, were present everywhere in our world, presumably capable of disguising themselves as innocuous substrates, all kinds of surfaces: metals, plastics, the cell membranes of every part of my own body. Somehow, though, I had managed to trick one into displaying at least some of its abilities. At the completion of the detailed scan, the SEM reverted automatically to low-resolution near-real-time images, just in time for me to see the mysterious nano-device explode into a cloud of simple molecules, exactly the kinds of things that the hard-vacuum pumps were designed to remove efficiently, leaving no evidence that it had been there at all, and taking with it a substantial fraction of the device I had been trying to construct. No wonder my attempts at fabrication had been unsuccessful: something out there was actively preventing exactly such a development.
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Part 2