New posts in perturbation-theory

Can we approximate a.e. invertible matrices with everywhere invertible matrices in $L^2$ sense?

Reference: Continuity of Eigenvectors

Perturbative solution to $x^3+x-1=0$

Melnikov's method, homoclinic orbits, and bifurcation values

Boundary layer problem

How to solve an ODE with $y^{-1}$ term

Perturbation method to solve $\epsilon x^3=x+\epsilon$

Inverse of symmetric positive definite perturbation of symmetric positive definite matrix

How to find the critical point for this Coulomb field

Matrix function converges, how about the eigenvalues?

How to perturb nonzero elements to get nonzero elements

Series expansion of the determinant for a matrix near the identity

Characterizing (stationary) points by the number of valleys one can descent into