Graduate Dimension of \lambda constant in \delta potential

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In the context of the time-independent Schrödinger equation with a delta potential, the potential is defined as V(x) = -λδ(x), where λ > 0. The dimension of the potential V(x) is established as ML²T⁻². The wave function ψ(x) has a dimension of L⁻½, while the delta function δ(x) is determined to have a dimension of L⁻¹ based on the integral property ∫ dx δ(x) = 1. Consequently, the dimension of λ can be derived from these relationships, leading to a clear understanding of its dimensionality in the context of the delta potential. This analysis highlights the interplay between the dimensions of the potential, wave function, and delta function in quantum mechanics.
LagrangeEuler
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Time independent Schroedinger equation in ##\delta## potential ##V(x)=-\lambda \delta(x)##, where ##\lambda >0## is given by
-\frac{\hbar^2}{2m}\frac{d^2}{d x^2}\psi(x)-\lambda \delta(x)\psi(x)=E\psi(x).
How to find dimension of ##\lambda##? Dimension of ##V(x)## is
[V(x)]=ML^2T^{-2}.
Because it is one dimensional problem dimension of ##\psi(x)## is
[\psi(x)]=L^{-\frac{1}{2}}.
Is then also
[\delta(x)]=L^{-\frac{1}{2}}?
 
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The dimension of ##\psi## is irrelevant. From ##\int dx\,\delta(x)=1## it follows that the dimension of ##\delta## is ##L^{-1}##. From that, the dimension of ##\lambda## should be easy.
 
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Demystifier said:
The dimension of ##\psi## is irrelevant. From ##\int dx\,\delta(x)=1## it follows that the dimension of ##\delta## is ##L^{-1}##. From that, the dimension of ##\lambda## should be easy.
Thank you very much.
 
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