Is it me or am I wrong that 100 million data entries cannot cover 100,000 galaxies? Also, why do cosmologists think that another civilization would emit infrared light waves? They always think in our limited understanding of space and time which change according to the latest theory. String theory is still a theory, based on math equations.
But then there is creation by design. However, I have a problem why the creator would create such an expanse for just one tiny sand grain to evolve into sentient beings. But then, maybe he/it just threw out the Singularity to see what would develop? No one knows and I believe possibly never will.
Another question is how long does infrared travel in space before it is absorbed by interstellar dust? Eventually it would get absorbed and re-emitted, which would "fog up" the ability to see the real source.
I'm guessing that they don't. I'm guessing that whatever wavelength they do use will slow down over time and distance and will look to us as Doppler "red-shifted" infrared waves.
-PJ