Empty Sum - Significance of "terms" of An Empty Sum

Significance of "terms" of An Empty Sum

Since an empty sum by definition has no terms, it seems contradictory to talk about its terms; however in practice there almost always is an expression that describes the terms of a summation, even if the range of summation happens to be empty. Since this expression is never instantiated in an empty sum, its value is irrelevant; for instance the harmonic number

is perfectly well defined. However, the kind of values denoted by the summand is of importance for the value of the summation; for instance, an empty summation of elements of a vector space has as value the zero vector in that space, rather than the number 0. Even more important is the fact that the operation is summation; by contrast, the empty product—a product of no factors at all—has as value of one.

Read more about this topic:  Empty Sum

Famous quotes containing the words significance of, significance, terms, empty and/or sum:

    “I am not afraid that I shall exaggerate the value and significance of life, but that I shall not be up to the occasion which it is.”
    —Henry David Thoreau (1817–1862)

    “I am not afraid that I shall exaggerate the value and significance of life, but that I shall not be up to the occasion which it is.”
    —Henry David Thoreau (1817–1862)

    “It is surely a matter of common observation that a man who knows no one thing intimately has no views worth hearing on things in general. The farmer philosophizes in terms of crops, soils, markets, and implements, the mechanic generalizes his experiences of wood and iron, the seaman reaches similar conclusions by his own special road; and if the scholar keeps pace with these it must be by an equally virile productivity.”
    —Charles Horton Cooley (1864–1929)

    “Full bottles are quiet; it’s the empty ones that make all the noise.”
    —Chinese proverb.

    “The sum and substance of female education in America, as in England, is training women to consider marriage as the sole object in life, and to pretend that they do not think so.”
    —Harriet Martineau (1802–1876)