Exponentials as eigenfunctions in LTI Systems

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The discussion focuses on the concept of eigenvalues in linear time-invariant (LTI) systems, specifically regarding the expression e^{s t} as an eigenvalue. The user questions the validity of the eigenvalue equation involving integrals of the system's impulse response function h(t) and its Laplace transform H(s). There is a belief that the integrals H(s) and the integral of h(τ) should be unique, suggesting that there is only one solution for the relationship H(s) = ∫_{-\infty}^{\infty} h(τ) e^{-s τ} dτ. The conversation also references the fundamental theorem of calculus to support the uniqueness of the integral. Overall, the thread seeks clarity on the uniqueness of solutions in the context of eigenvalue equations for LTI systems.
Tanja
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I hope I catched the correct forum.

Under http://en.wikipedia.org/wiki/LTI_system_theory
e^{s t} is an eigenvalue.
I don't really understand that the following is an eigenvalue equation:
\quad = e^{s t} \int_{-\infty}^{\infty} h(\tau) \, e^{-s \tau} \, d \tau
\quad = e^{s t} H(s),

where

H(s) = \int_{-\infty}^\infty h(t) e^{-s t} d t .

The integrals H(s) and \int_{-\infty}^{\infty} h(\tau) \, e^{-s \tau} \, d \tau should be unique, isn't it? So there is only one solution for H(s) = \int_{-\infty}^{\infty} h(\tau) \, e^{-s \tau} \, d \tau with one e^{s t}, isn't it?

Thanks
Tanja
 
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e^{s t} is an eigenvalue.
I don't really understand that the following is an eigenvalue equation:
\quad = e^{s t} \int_{-\infty}^{\infty} h(\tau) \, e^{-s \tau} \, d \tau
\quad = e^{s t} H(s),

where

H(s) = \int_{-\infty}^\infty h(t) e^{-s t} d t.

The integrals H(s) and \int_{-\infty}^{\infty} h(\tau) \, e^{-s \tau} \, d \tau should be unique, isn't it? So there is only one solution for H(s) = \int_{-\infty}^{\infty} h(\tau) \, e^{-s \tau} \, d \tau with one e^{s t}, isn't it?
F(x) = \int_a^xf(t)dt is unique by the fundamental theorem of calculus.
 
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The standard _A " operator" maps a Null Hypothesis Ho into a decision set { Do not reject:=1 and reject :=0}. In this sense ( HA)_A , makes no sense. Since H0, HA aren't exhaustive, can we find an alternative operator, _A' , so that ( H_A)_A' makes sense? Isn't Pearson Neyman related to this? Hope I'm making sense. Edit: I was motivated by a superficial similarity of the idea with double transposition of matrices M, with ## (M^{T})^{T}=M##, and just wanted to see if it made sense to talk...

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