# Division ring

A ring with division is a (not necessarily associative) ring in which the equations

$$a \cdot x = b \quad;\quad\quad y \cdot a = b $$

are solvable for any two elements $a$ and $b$, where $a \ne 0$. If the solutions of these equations are uniquely determined, then the ring is called a quasi-division ring. In contrast to an arbitrary division ring, a quasi-division ring cannot have divisors of zero (cf. Zero divisor); the non-zero elements of a quasi-division ring form a quasi-group with respect to multiplication. Each (not necessarily associative) ring without divisors of zero can be imbedded in a quasi-division ring. An associative division ring is an (associative) skew-field. See also Division algebra.

#### References

[1] | A.G. Kurosh, "Lectures on general algebra" , Chelsea (1963) (Translated from Russian) |

#### Comments

#### References

[a1] | N. Jacobson, "The theory of rings" , Amer. Math. Soc. (1943) |

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Division ring.

*Encyclopedia of Mathematics.*URL: http://encyclopediaofmath.org/index.php?title=Division_ring&oldid=31221