Fear of trains the social norms of a realistic fear, this anxiety may be classified as a specific phobia about trains. "Campbell's Psychiatric Dictionary" puts fear of trains under the "vehicle phobia", together with fears of boats, airplanes, automobiles, and other forms of transportation. A 1913 short story "Terror" by Jun'ichirō Tanizaki is a first-person narrative of a young man suffering of the morbid fear of travel in trains and streetcars. Tanizaki uses the German word , "railroad sickness". Other travel-related anxieties include: Other transport-related disorders include: Fear of trains The fear of trains is anxiety and fear associated with trains, railways, and
Irrational number A stronger result is the following: Every rational number in the interval formula_23 can be written either as "a" for some irrational number "a" or as "n" for some natural number "n". Similarly, every positive rational number can be written either as formula_24 for some irrational number "a" or as formula_25 for some natural number "n". It is not known if formula_26 (or formula_27) is irrational. In fact, there is no pair of non-zero integers formula_28 for which it is known whether formula_29 is irrational. Moreover, it is not known whether or not the set formula_30 is algebraically independent over