17 pictures that show how mind-bogglingly large the Universe is

[Irish_Dem]

13. The Fermi paradox is not resolved?

https://forum.effectivealtruism.org/posts/kvZshdx5FzTPjyhxG/the-fermi-paradox-has-not-been-dissolved

Conclusion
In this essay I have argued that the analysis presented by Sandberg et al. concerning the dissolution of the Fermi paradox is multiply flawed. First, the approach of multiplying many parameter intervals with an upper bound at one, but no corresponding lower bound, predisposes the resulting distribution of the number of alien civilisations to exhibit a very long negative tail, which drives the reported result. Second, the method used to estimate the distribution of the parameter fl is insufficiently justified, and the main result of the paper disappears if this parameter is modelled in the same way as the other parameters. Furthermore, the very low estimates of fl and fi reported in the literature review as supporting evidence are mostly misstated from their sources, and are based on vague speculation rather than specific scientific evidence. Third, an alternative modelling approach which incorporates the evidence of the early emergence of life on Earth, and also makes slightly different assumptions regarding the other parameters of the Drake equation, finds a much lower probability that Earth is unique in the Milky Way, and a negligible chance of being alone in the universe. Overall, while Sandberg et al. have made a significant contribution to the study of the Fermi Paradox and the Drake equation by illustrating how computational methods can be used to construct distributions for the probability of various numbers of alien civilisations, I do not believe they have succeeded in showing that the probability of Earth being alone is sufficiently high so as to dissolve the Fermi paradox. Indeed, I present two different set of parameters which yield a negligible probability of Earth being alone in the universe, and hence insomuch as the estimated number of alien civilisations depends crucially on the chosen modelling assumptions, the Fermi Paradox remains very much an open question.