The Passage of Time

As everyone knew, energy and energy sources were not the same thing, so there was no need to elaborate. Humanity understood this perfectly well.

Take the antimatter fuel currently used by Lyra and other Level 4 Civilizations. It was merely a high-level form of energy utilization. Producing antimatter consumed more energy than the antimatter itself contained, and that energy came from stars.

That was precisely why the Dynamic Image Civilization had needed one-sixth of a Dyson Sphere as a factory. Its energy source had still been a star.

Energy spontaneously transferred from high-temperature objects to low-temperature objects. This was one of the fundamental principles of the Second Law of Thermodynamics, an empirical summary that all physical and chemical processes related to thermal motion within finite space and time were irreversible.

This law was not wrong, but it had a range of applicability. It only applied to systems composed of very large numbers of molecules and macroscopic processes within limited bounds; it did not apply to small microscopic systems. As for extending it to the entire universe and claiming that the universe would end in heat death, humanity still did not know whether that was correct.

But humanity could now be certain that even a Level Six Civilization could not violate the Second Law of Thermodynamics. They could not reverse this process either.

Therefore, although the energy levels they utilized were far higher than humanity's current ones, their ultimate source of energy was still the heat produced by the process of Cosmic Entropy Increase—the process described by the Second Law of Thermodynamics, in which heat spontaneously transferred from high-temperature objects to low-temperature objects.

And in this process, heat could not be converted with one hundred percent efficiency. There would inevitably be losses.

This was not the same concept as the commonly