Astraphobia Astraphobia Astraphobia, also known as astrapophobia, brontophobia, keraunophobia, or tonitrophobia is an abnormal fear of thunder and lightning, a type of specific phobia. It is a treatable phobia that both humans and animals can develop. The term astraphobia is composed of the words ἀστραπή (astrape; lightning) and φόβος (phobos; fear). A person with astraphobia will often feel anxious during a thunderstorm even when they understand that the threat to them is minimal. Some symptoms are those accompanied with many phobias, such as trembling, crying, sweating, panicked reactions, the sudden feeling of using the bathroom, nausea, the feeling of dread, insertion
Irrational number rely on deductive reasoning for proof.” This method of exhaustion is the first step in the creation of calculus. Theodorus of Cyrene proved the irrationality of the surds of whole numbers up to 17, but stopped there probably because the algebra he used could not be applied to the square root of 17. It was not until Eudoxus developed a theory of proportion that took into account irrational as well as rational ratios that a strong mathematical foundation of irrational numbers was created. Geometrical and mathematical problems involving irrational numbers such as square roots were addressed very early during the