In the Equation: Number of Civilizations =Np × Flife ×

question 60

Multiple Choice

In the equation: Number of Civilizations =Np × flife × fcivilization × fnow
What do we mean by fnow?

• A)the fraction of planets with civilizations on which the civilizations exist now
• B)the fraction of time since the Big Bang represented by the present era
• C)the fraction of all species ever to exist that we currently are aware of
• D)the fraction of planets in the galaxy on which a civilization could theoretically develop now
• E)the fraction of civilizations in the universe that currently are sending messages to us

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Definitions:

Tit-For-Tat Strategy

A strategy in game theory where a player replicates the opponent's previous action, generally used in reference to cooperation or retaliation.

Cheat

To act dishonestly or unfairly in order to gain an advantage, particularly in contexts like games, exams, or sports.

Payoff Matrix

A table that describes the potential outcomes of a game or decision involving multiple players, showing the payoffs for each strategy combination.

Dominant Strategy

An action in game theory that yields the best outcome for a player, regardless of what the other players do.