2 citations · 3 across the 4 of their papers we have counts for
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Polystability in positive characteristic and degree lower bounds for invariant rings
Harm Derksen, Visu Makam
We develop a representation theoretic technique for detecting closed orbits that is applicable in all characteristics. Our technique is based on Kempf's theory of optimal subgroups…
Maximum likelihood estimation for matrix normal models via quiver representations
Harm Derksen, Visu Makam
In this paper, we study the log-likelihood function and Maximum Likelihood Estimate (MLE) for the matrix normal model for both real and complex models. We describe the exact number…
Singular tuples of matrices is not a null cone (and, the symmetries of algebraic varieties)
Visu Makam, Avi Wigderson
The following multi-determinantal algebraic variety plays a central role in algebra, algebraic geometry and computational complexity theory: , consisting of all $…
Invariant theory and wheeled PROPs
Harm Derksen, Visu Makam
We study the category of wheeled PROPs using tools from Invariant Theory. A typical example of a wheeled PROP is the mixed tensor algebra , whe…
An exponential lower bound for the degrees of invariants of cubic forms and tensor actions
Harm Derksen, Visu Makam
Using the Grosshans Principle, we develop a method for proving lower bounds for the maximal degree of a system of generators of an invariant ring. This method also gives lower boun…
Weyl's polarization theorem in positive characteristic
Harm Derksen, Visu Makam
Let be an -dimensional algebraic representation over an algebraically closed field of a group . For , we study the invariant rings for the diagon…