TOPICS
Search

Kollár-Pardon Conjecture


The Kollár-Pardon conjecture asserts that a connected normal projective complex variety has a semialgebraic presentation of its universal cover precisely when the cover has a product decomposition

 X^~=D×C^m×F,

where m>=0 is an integer, D is a bounded symmetric domain, and F is a simply connected normal projective variety. A point is allowed for either D or F.

The presentation means a biholomorphism with a semialgebraic open subset of a projective variety, with openness in the ordinary complex topology. In affine algebraic charts, semialgebraic means a finite Boolean combination of real polynomial equalities and inequalities in real and imaginary coordinates. Neither the biholomorphism nor the deck transformations is required to be algebraic or to preserve the chosen semialgebraic structure. The projective factor may be singular. For curves the three possibilities are the projective line, the complex line, and the unit disk.


See also

Bounded Symmetric Domain, Normal Variety, Projective Variety, Semialgebraic Set, Universal Cover

Explore with Wolfram|Alpha

References

Kollár, J. and Pardon, J. "Algebraic Varieties with Semialgebraic Universal Cover." J. Topol. 5, 199-212, 2012. https://doi.org/10.1112/jtopol/jts001.

Cite this as:

Weisstein, Eric W. "Kollár-Pardon Conjecture." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Kollar-PardonConjecture.html

Subject classifications