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MatFac15 :: tangentKernelDimension

tangentKernelDimension -- compute the dimension of the kernel of the tangent map

Synopsis

Description

The module M =coker M0 is a syzygy module of N over the coordinate ring of a cubic hypersurface. Using some exact sequences we compute the kernel of map from the firt order deformation space of N as an SX module and to the first order deformations of M.

i1 : kk=ZZ/10007

o1 = kk

o1 : QuotientRing
i2 : S=kk[x_0..x_4]

o2 = S

o2 : PolynomialRing
i3 : N=constructEx1(S);
i4 : (M0,M1) = matrixFactorizationFromModule(N);
i5 : time cd=tangentKernelDimension(N,M0)
     -- used 0.452893 seconds

o5 = 3

Ways to use tangentKernelDimension :

  • tangentKernelDimension(Module,Matrix)