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WOEFUL COMPLETENESS. “We show that these assumptions allow us to do our calculation analytically, and we get a result very similar to that of another haystack, as calculated by Tarter et al. (2010): our current search completeness is extremely low, akin to having searched something like a large hot tub or small swimming pool's worth of water out of all of Earth's oceans.” https://lnkd.in/dKzsrBv View in LinkedIn

THE SAD REALITY. “The total volume of Earth's oceans is approximately 1.335 × 10(21) liters, meaning that the total searching done to date is equivalent of ~8000 l of seawater, which is somewhere between the volumes of a large hot tub and a small swimming pool.” https://lnkd.in/dKzsrBv View in LinkedIn

THE CALCULATION. “To illustrate a haystack calculation, we have chosen a particular set of haystack dimensions that might exemplify any particular narrowband radio search with an eye toward determining whether we can yet rule out large numbers of narrowband transmitters in the solar neighborhood (that is, determining a rigorous—if weak—upper limit for SETI).” https://lnkd.in/dKzsrBv View in LinkedIn

LIMITATIONS. “Calculating search completeness requires defining the boundaries of the search; in many cases, one can always look harder for ever rarer or more subtle or more extreme events. The huge range of potential technosignatures also means that one survey cannot hope to be sensitive to all of them, requiring searchers to hypothesize a particular form of signature that they can put interesting limits on with their survey.” https://lnkd.in/dKzsrBv View in LinkedIn

PRIORITIZATION. “As we have seen, the choice of the number of dimensions for a haystack depends on the method used, and for many surveys, multiple dimensions can be "collapsed" into a single dimension, simplifying the problem. For our present purposes, we choose the following (not necessarily orthogonal) dimensions of a radio communication SETI haystack. (See criteria).” https://lnkd.in/dKzsrBv View in LinkedIn

TARGET SENSITIVITY. “This will also be true with haystacks in general: the size, shape, and dimensionality of the haystack—and one's completeness in searching it—will necessarily depend on the sorts of needles one is searching for.” https://lnkd.in/dKzsrBv View in LinkedIn

SEARCH SPEEDS. “The figure of merit one chooses thus depends on the haystack one is searching and how one is searching it; because different searches historically have had very different search methodologies—even among narrowband radio searches at the same wavelengths—it can be difficult to compare their relative search speeds.” https://lnkd.in/dKzsrBv View in LinkedIn

CAUSE AND EFFECT OVER TIME. “A star dying soon after the beginning of the universe could be disrupting cell phone reception today.” https://lnkd.in/dQjsKCx View in LinkedIn

A DYNAMIC COSMOS. “Black holes are commonly surrounded by a hot 'soup' of plasma particles that carry a magnetic field.” https://lnkd.in/dh362Q9 View in LinkedIn