However, there are
still the following points of criticism about the Drake
equation: The factor n represents the number of habitable planets. In our solar system there are three habitable planets. And only one has life. The triple number of habitable planets does not mean that there are three times as many civilizations. Basically, you're just looking for a planet with a civilization. The factor n is therefore 1 and can therefore be omitted. The factor fc can also be set to 1. If f_{c} = 0.5, this only means that half of civilizations do not want to communicate. But that doesn't make it any less civilizations. The factor f_{c} can also be neglected. This allows to modify the Drake equation. The modified Drake equation is:
This is how the "modified Drake equation" can be formulated:

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