Nabla is the symbol (∇). The name comes from the Greek word for a Hebrew harp, which had a similar shape. Related words also exist in Aramaic and Hebrew. The symbol was first used by William Rowan Hamilton in the form of a sideways wedge: ⊲. Another, less-common name for the symbol is atled (delta spelled backwards), because the nabla is an inverted Greek letter delta. In actual Greek usage, the symbol is called ανάδελτα, anádelta, which means "u...
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Nabla is the symbol (∇). The name comes from the Greek word for a Hebrew harp, which had a similar shape. Related words also exist in Aramaic and Hebrew. The symbol was first used by William Rowan Hamilton in the form of a sideways wedge: ⊲. Another, less-common name for the symbol is atled (delta spelled backwards), because the nabla is an inverted Greek letter delta. In actual Greek usage, the symbol is called ανάδελτα, anádelta, which means "upside-down delta".
The nabla symbol is available in standard HTML as ∇ and in LaTeX as \nabla. In Unicode, it is the character at code point U+2207, or 8711 in decimal notation.
Nabla is used in mathematics to denote the del operator. It also can refer to a connection in differential geometry, as well as the all relation (most commonly in lattice theory). It was introduced by the Irish mathematician and physicist William Rowan Hamilton in 1837 . William Thomson wrote in 1884: "I took the liberty of asking Professor Bell whether he had a...
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