The universal cover of an algebra without double bypass
نویسنده
چکیده
Let A be a basic and connected finite dimensional algebra over a field k of characteristic zero. We show that if the quiver of A has no double bypass then the fundamental group (as defined in [17]) of any presentation of A by quiver and relations is the quotient of the fundamental group of a privileged presentation of A. Then we show that the Galois covering of A associated with this privileged presentation satisfies a universal property with respect to the connected Galois coverings of A in a similar fashion to the universal cover of a topological space.
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