Synopsis
The paper “A qualitative classification of extraterrestrial civilizations” by Valentin D. Ivanov et al. proposes a new classification system for extraterrestrial civilizations (ETCs) based on their abilities to modify and integrate with their environments. The classification is as follows:
Class 0: Uses the environment as it is.
Class 1: Modifies the environment to fit its needs.
Class 2: Modifies itself to fit the environment.
Class 3: Fully integrated with the environment.
This classification is combined with the classical Kardashev scale, which measures the advancement of a civilization based on the amount of energy it can harness, to form a two-dimensional method for interpreting ETC properties.
The authors argue that the available energy is not a unique measure of ETC progress, as it may not correlate with how well that energy is used. The possibility of progress without increased energy consumption implies a lower detectability, meaning that the existence of a Kardashev Type III ETC in the Milky Way cannot be ruled out. This reasoning weakens the Fermi paradox, allowing for the existence of advanced, yet not energy-hungry, low-detectability ETCs.
The integration of ETCs with the environment will make it impossible to distinguish technosignatures from natural phenomena. Therefore, the most likely opportunity for SETI searches to find advanced ETCs is to look for beacons specifically set up by them for young civilizations like ours. Another SETI window of opportunity is to search for ETCs at a technological level similar to ours.
