I use Bousso’s causal diamond measure to make a statistical prediction for the dark matter abundance, assuming an axion with a large decay constant fa ≫ 10 GeV. Using a crude approximation for observer formation, the prediction agrees well with observation: 30% of observers form in regions with less dark matter than we observe, while 70% of observers form in regions with more dark matter. Large...

It is explained in detail why the Anthropic Principle (AP) cannot yield any falsifiable predictions, and therefore cannot be a part of science. Cases which have been claimed as successful predictions from the AP are shown to be not that. Either they are uncontroversial applications of selection principles in one universe (as in Dicke’s argument), or the predictions made do not actually logicall...

We discuss the Carter's formula about the mankind evolution probability following the derivation proposed by Barrow and Tipler. We stress the relation between the existence of billions of galaxies and the evolution of at least one intelligent life, whose living time is not trivial, all over the Universe. We show that the existence probability and the lifetime of a civilization depend not only o...

In the context of open inflation, we calculate the probability distribution for the density parameter V . A large class of two field models of open inflation do not lead to infinite open universes, but to an ensemble of inflating islands of finite size, or ‘‘quasi-open’’ universes, where the density parameter takes a range of values. Assuming we are typical observers, the models make definite p...

We evaluate the problem of galaxy formation in the landscape approach to phenomenology of the axion sector. With other parameters of standard ΛCDM cosmology held fixed, the density of cold dark matter is bounded below relative to the density of baryonic matter by the requirement that structure should form before the era of cosmological constant domination of the universe. Galaxies comparable to...

In this lecture I make some educated guesses, about the landscape of string theory vacua. Based on the recent work of a number of authors, it seems plausible that the lanscape is unimaginably large and diverse. Whether we like it or not, this is the kind of behavior that gives credence to the Anthropic Principle. I discuss the theoretical and conceptual issues that arise in developing a cosmolo...

Anthropic reasoning is a form of statistical reasoning based upon finding oneself a member of a particular reference class of conscious beings. By considering empirical distribution functions defined over animal life on Earth, we can deduce that the vast bulk of animal life is unlikely to be conscious.