Definition:Transposition
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Definition
Let $S$ be a set.
A transposition on $S$ is a $2$-cycle.
That is, a transposition is a permutation $\rho$ on $S$ which exchanges, or transposes, exactly two elements of $S$.
Thus if $\rho$ is a transposition which transposes two elements $r, s \in S$, it follows from the definition of fixed elements that:
- $\Fix \rho = S \setminus \set {r, s}$
Adjacent Transposition
Let $S_n$ denote the symmetric group on $n$ letters.
An adjacent transposition is a transposition that exchanges two consecutive integers $j$ and $j + 1$, where $1 \le j < n$.
In cycle notation, they are denoted:
- $\begin {pmatrix} j & j + 1 \end {pmatrix}$
Also known as
A transposition is colloquially known as a two-letter swap.
Sources
- 1966: Richard A. Dean: Elements of Abstract Algebra ... (previous) ... (next): $\S 1.6$
- 1968: Ian D. Macdonald: The Theory of Groups ... (previous) ... (next): Appendix: Elementary set and number theory
- 1971: Allan Clark: Elements of Abstract Algebra ... (previous) ... (next): Chapter $2$: The Symmetric Groups: $\S 79$
- 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): transposition
- 1996: John F. Humphreys: A Course in Group Theory ... (previous) ... (next): Chapter $9$: Permutations
- 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): transposition
- 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): transposition