The descending wedge symbol ∨ may represent:
- Logical disjunction in propositional logic
- Join in lattice theory
- The wedge sum in topology
- The V sign, a symbol representing peace among other things
The vertically reflected symbol, ∧, is a wedge, and often denotes related or dual operators.
The ∨ symbol was introduced by Russell and Whitehead in Principia Mathematica, where they called it the Logical Sum or Disjunctive Function.[1]
In Unicode the symbol is encoded U+2228 ∨ LOGICAL OR (∨, ∨). In TeX, it is \vee or \lor.
One motivation and the most probable explanation for the choice of the symbol ∨ is the latin word "vel" meaning "or" in the inclusive sense. Several authors use "vel" as name of the "or" function.[2][3][4][5][6][7][8][9]
References
[edit]- ^ Whitehead, Alfred North (2005). Principia mathematica, by Alfred North Whitehead ... and Bertrand Russell.
- ^ Rueff, Marcel; Jeger, Max (1970). Sets and Boolean Algebra. American Elsevier Publishing Company. ISBN 978-0-444-19751-1.
- ^ Trappl, Robert (1975). Progress in Cybernetics and Systems Research. Hemisphere Publishing Corporation. ISBN 978-0-89116-240-7.
- ^ Constable, Robert L. (1986). Implementing Mathematics with the Nuprl Proof Development System. Prentice-Hall. ISBN 978-0-13-451832-9.
- ^ Malatesta, Michele (1997). The Primary Logic: Instruments for a Dialogue Between the Two Cultures. Gracewing Publishing. ISBN 978-0-85244-499-3.
- ^ Harris, John W.; Stöcker, Horst (1998-07-23). Handbook of Mathematics and Computational Science. Springer Science & Business Media. ISBN 978-0-387-94746-4.
- ^ Tidman, Paul; Kahane, Howard (2003). Logic and Philosophy: A Modern Introduction. Wadsworth/Thomson Learning. ISBN 978-0-534-56172-7.
- ^ Kudryavtsev, Valery B.; Rosenberg, Ivo G. (2006-01-18). Structural Theory of Automata, Semigroups, and Universal Algebra: Proceedings of the NATO Advanced Study Institute on Structural Theory of Automata, Semigroups and Universal Algebra, Montreal, Quebec, Canada, 7-18 July 2003. Springer Science & Business Media. ISBN 978-1-4020-3817-4.
- ^ Denecke, Klaus; Wismath, Shelly L. (2009). Universal Algebra and Coalgebra. World Scientific. ISBN 978-981-283-745-5.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction