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Is there an infinite-dimensional, non-commutative complex local algebra $A$ (which is not a field) with the (unique) maximal left-ideal finitely generated as a left ideal? Or as a right ideal?

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up vote 1 down vote accepted

Yes, the following should do the trick:

Let $D$ be any skew field over $\mathbb{C}$. Then $D[[X]]$ is a local ring with maximal left ideal $(X)$ (see Lam, A first Course in noncommutative Rings, after 19.7) and $D[[X]]$ is clearly infinite-dimensional as $\mathbb C$-algebra.

So it suffices to find $D$. According to Cohn's book quoted in


$D$ can be choosen to be a twisted Laurent series ring over $\mathbb C$ (see Prop. 2.3.5 in google books).

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Perfect, thank you! – Alex Ortega Mar 14 '12 at 0:55

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