English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Many articulations of the Fermi Paradox have as a premise, implicitly orexplicitly, that humanity has searched for signs of extraterrestrial radiotransmissions and concluded that there are few or no obvious ones to be found.Tarter et al. (2010) and others have argued strongly to the contrary: brightand obvious radio beacons might be quite common in the sky, but we would notknow it yet because our search completeness to date is so low, akin to havingsearched a drinking glass's worth of seawater for evidence of fish in all ofEarth's oceans. Here, we develop the metaphor of the multidimensional "CosmicHaystack" through which SETI hunts for alien "needles" into a quantitative,eight-dimensional model and perform an analytic integral to compute thefraction of this haystack that several large radio SETI programs havecollectively examined. Although this model haystack has many qualitativedifferences from the Tarter et al. (2010) haystack, we conclude that thefraction of it searched to date is also very small: similar to the ratio of thevolume of a large hot tub or small swimming pool to that of the Earth's oceans.With this article we provide a Python script to calculate haystack volumes forfuture searches and for similar haystacks with different boundaries. We hopethis formalism will aid in the development of a common parameter space for thecomputation of upper limits and completeness fractions of search programs forradio and other technosignatures.

How Much SETI Has Been Done? Finding Needles in the n-Dimensional Cosmic Haystack