What is Eigenvalue problem: Definition and 85 Discussions

In mathematics, the quadratic eigenvalue problem (QEP), is to find scalar eigenvalues



λ


{\displaystyle \lambda }
, left eigenvectors



y


{\displaystyle y}
and right eigenvectors



x


{\displaystyle x}
such that




Q
(
λ
)
x
=
0

and


y




Q
(
λ
)
=
0
,


{\displaystyle Q(\lambda )x=0{\text{ and }}y^{\ast }Q(\lambda )=0,}
where



Q
(
λ
)
=

λ

2



A

2


+
λ

A

1


+

A

0




{\displaystyle Q(\lambda )=\lambda ^{2}A_{2}+\lambda A_{1}+A_{0}}
, with matrix coefficients




A

2


,


A

1


,

A

0





C


n
×
n




{\displaystyle A_{2},\,A_{1},A_{0}\in \mathbb {C} ^{n\times n}}
and we require that




A

2




0


{\displaystyle A_{2}\,\neq 0}
, (so that we have a nonzero leading coefficient). There are



2
n


{\displaystyle 2n}
eigenvalues that may be infinite or finite, and possibly zero. This is a special case of a nonlinear eigenproblem.



Q
(
λ
)


{\displaystyle Q(\lambda )}
is also known as a quadratic polynomial matrix.

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  1. G

    Put the eigenvalue function in self-adjoint form

    Here’s my work: The integrating factor I find is (x^(2)-1)^1/2. The self adjoint form I find is -d/dx (((1-x^(2))^(3/2))*dy/dx))=k(x^(2)-1)^(1/2). Am I right?
  2. CuriousLearner8

    A Eigenvalue Problem of Quantum Mechanics

    Hello, I hope you are doing well. I had a question about the eigenvalue problem of quantum mechanics. In a past class, I remember it was strongly emphasized that the eigenvalues of an eigenvalue problem is what we measure in the laboratory. ##A\psi = a\psi## where A would be the operator...
  3. A

    Engineering Book considering FEM analysis for complex eigenvalues (incl. damping)

    Can anyone recommend a book in which complex eigenvalue problems are treated? I mean the FEM analysis and the theory behind it. These are eigenvalue problems which include damping. I think that it is used for composite materials and/or airplane engineering (maybe wing fluttering?).
  4. Viona

    Operator acts on a ket and a bra using Dirac Notation

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  5. B

    I It seems that the eigenvalue problem rules out the possibility of E=0?

    Since the eigenvalue problem can't distinguish between a non-existent wavefunction (and therefore a non-existent particle), and the energy being zero. This is the next thing that has started bothering me on my journey to understand quantum mechanics. For example, in the algebraic derivation of...
  6. Andrew1235

    Finding the directions of eigenvectors symmetric eigenvalue problem

    In the symmetric eigenvalue problem, Kv=w^2*v where K~=M−1/2KM−1/2, where K and M are the stiffness and mass matrices respectively. The vectors v are the eigenvectors of the matrix K~ which are calculated as in the example below. How do you find the directions of the eigenvectors? The negatives...
  7. P

    A Eigenvalues of block matrix/Related non-linear eigenvalue problem

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  8. T

    I Simple Generalized Eigenvalue problem

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  9. M

    A Eigenvalue problem: locating complex eigenvalues via frequency scan

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  10. T

    I Eigenvalue Problem -- Justification

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  11. bluesky314

    I Question about an eigenvalue problem: range space

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  12. peguerosdc

    I Confusion with Dirac notation in the eigenvalue problem

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  13. M

    Quadratic eigenvalue problem and solution (solved in Mathematica)

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  14. M

    MATLAB Solving Polynomial Eigenvalue Problem

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  15. S

    Eigenvalue problem -- Elastic deformation of a membrane

    Homework Statement An elastic membrane in the x1x2-plane with boundary circle x1^2 + x2^2 = 1 is stretched so that point P(x1,x2) goes over into point Q(y1,y2) such that y = Ax with A = 3/2* [2 1 ; 1 2] find the principal directions and the corresponding factors of extension or contraction of...
  16. M

    Mathematica Eigenvalue problem and badly conditioned matrices

    Hi PF! I am trying to solve the eigenvalue problem ##A v = \lambda B v##. I thought I'd solve this by $$A v = \lambda B v \implies\\ B^{-1} A v = \lambda v\implies\\ (B^{-1} A - \lambda I) v = 0 $$ and then using the built in function Eigenvalues and Eigenvectors on the matrix ##B^{-1}A##. But...
  17. M

    A Solving an ODE Eigenvalue Problem via the Ritz method

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  18. M

    A Eigenvalue Problem and the Calculus of Variations

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  19. A

    MHB A question on matrix's eigenvalue problem from Eberhard Zeidler's first volume of Nonlinear Function

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  20. C

    Sturm-Liouville Eigenvalue Problem (Variational Method?)

    Homework Statement Using Sturm-Liouville theory, estimate the lowest eigenvalue ##\lambda_0## of... \frac{d^2y}{dx^2}+\lambda xy = 0 With the boundary conditions, ##y(0)=y(\pi)=0## And explain why your estimate but be strictly greater than ##\lambda_0##Homework Equations ##\frac{d}{dx} \left...
  21. Mr Davis 97

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  22. Hamza Abbasi

    I Eigenvalue Problem: What Is It?

    While reading problems in my physics book , I encountered a statement very often "Eigen Value Problem" , I read about it from many sources , but wasn't able to understand it . So what exactly is an Eigen Value Problem?
  23. I

    Eigenvalue Problem: Find All Eigen-Values & Eigen-Fns

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  24. J

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  25. M

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  26. M

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  27. K

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  28. maajdl

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  29. N

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  30. H

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  31. T

    What is an eigenvalue problem?

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  32. V

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  33. P

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  34. J

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  35. W

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  36. P

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  37. J

    How to solve this kind of eigenvalue problem?

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  38. D

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  39. Y

    Help finding a general solution for an eigenvalue problem

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  40. C

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  41. J

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  42. R

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  43. H

    Solving Eigenvalue Problem with Periodic BCs: Find b for Self-Adjointness

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  44. D

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  45. M

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  46. 3

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  47. C

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  48. Hootenanny

    Mathematica Generalised Eigenvalue Problem in Mathematica

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  49. M

    Multilinear eigenvalue problem

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  50. A

    True or false eigenvalue problem

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