>> Why can’t they make visible light with an antenna?
> In terms of normal radio antenna designs, you could, I think, but antennas need to be sized proportional to the wave length of the light.
There is also one more difference to mention. For antenna design in radio frequencies the metals are taken as perfect conductors—meaning that the fields inside the metal are zero. This assumption relies on the fact that electrons in the metal respond the electric field basically instantaneously. However, the optical frequencies are significantly higher, so the movement of the electron cloud in the metal is no longer instantaneous relative to the outside fields. As a result metals at frequencies of visible light are way less "metal-like" when looking from the perspective of RF antenna design, so you can't directly use the exact same approaches for designing antennas.
It should be noted that ID+PIN is not just for the elections: it covers all of the e-services from online health records to online banking, also including digitally signing documents in your name. So I would assume that people wouldn't trust their ID+PIN to strangers.
Just a quick nitpick regarding to cultural/ethnical similarity with Russia: although the Baltic states were part of Russian Empire, the local culture had also strong German influences. Up until end of 19th century the Baltic Germans were the ruling class (although the region was in Russian Empira). So the local culture was mix of German and Russian influences, which makes it somewhat different with rest of USSR states.
> The input data usually is in decimal and needs only a small part of the accuracy that a decimal float format offers.
I would actually argue that majority of the time data is not in decimal. For example in computational science, for which the Herbie seems to be aimed at, you very rarely have decimal numbers. While input parameters to computations might be a decimal numbers, everything else apart from initial conditions would be irrational numbers. A good example would be numerical solving of harmonic oscillator equation -- the initial conditions might very well be decimal, but the numerical solution is not (neither would be analytic solution).
> When converting decimal to binary floating point numbers you will often use the full accuracy of the float format because the decimal floating point numbers can't be represented exactly in binary.
Inability to exactly represent decimal numbers isn't really the problem in these cases. Summation of numbers with wildly varying magnitudes would be problematic for decimal floats as well.