- The University of Utah operates a cosmic ray detector called the Fly’s Eye II, situated at the Dugway Proving Ground about an hour’s drive from Salt Lake City. The Fly’s Eye consists of an array of telescopes which stare into the night sky and record the blue flashes which result when very high energy cosmic rays slam into the atmosphere. From the height and intensity of the flash, one can calculate the nature of the particle and its energy.
- Existential quantification (Wikipedia)
In predicate logic, an existential quantification is a type of quantifier, a logical constant which is interpreted as “there exists”, “there is at least one”, or “for some”. It is usually denoted by the logical operator symbol ∃, which, when used together with a predicate variable, is called an existential quantifier ("∃x" or “∃(x)” or “(∃x)”). Existential quantification is distinct from universal quantification (“for all”), which asserts that the property or relation holds for all members of the domain. Some sources use the term existentialization to refer to existential quantification.
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