Scientists invent the abacus
A high-tech spin on an ancient system could signal a revolution in high-speed computation. Andrew P Street reports.
In a thrilling development for science, an international team of researchers has developed the hottest new tool in computational technology: the abacus!
That might not sound entirely cutting edge, since humans have been using abaci for about 5000 years. But this abacus is a little bit more sophisticated than the ones being manipulated by trade-savvy Mesopotamians: it’s nanoscale, makes its calculations using pulses of light and does so billions of times per second.
The team’s paper in the journal Nature Communications outlines what this could mean for conventional computing.
Where a traditional abacus would use beads, this uses crystallisation of nanoscale phase-change materials, triggered by pulses of light: an amorphous state registers as zero while crystallisation reads as one.
With that binary system established, all the common abacus calculations can be performed – addition, subtraction, division, multiplication – at light-speed.
This isn’t just some obscure piece of tech-acrobatics, either. This is a development which could usher in a new age of computational speed, partially because using photons is much faster than traditional microchips which calculate by storing and freeing electrons in batteries of transistors. However, the real genius of this nanoscale photonic abacus is that it can both count and record the pulses of light in the one unit.
As the study’s lead author, Wolfram Pernice of the Institute of Physics at Germany’s Münster University, explains, "Rather than wooden beads as found on traditional abacuses, our innovative device calculates with pulses of light and simultaneously stores the result."
This is a huge change from the traditional system by which computers process data, where the calculation and storage duties are handled by separate pieces of architecture.
In the traditional Von Neumann design for computers, first published in 1945, these are called the arithmetic logic circuit and the control unit, respectively, except that by combining processes in the one unit this photonic system avoids the “Von Numann bottleneck” where data is transferred back and forth between the CPU and memory.
What’s even more encouraging is that this seems immensely scaleable for production.
The abaci reside on silicon and indium phosphide photonic microchips, which are simple to manufacture, meaning that this is less likely to be one of those exciting-sounding theoretical advancements which languish until economics and technology eventually catch up. Watch this space.