Which Potential Has a Lower Ground State Energy?

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The discussion focuses on comparing the ground state energies of two one-dimensional potentials, V0 and V1. The first potential, V0, is a square well with infinite boundaries, while V1 is a linear potential within the same boundaries. The participants are analyzing the implications of the Schrödinger equation and the behavior of eigenstates in these potentials. There is confusion regarding the treatment of non-square well potentials and how the value of V0 influences the ground state energy E1. Ultimately, the conclusion revolves around determining whether E0 is less than or greater than E1, emphasizing the fixed nature of E0 compared to the variable E1.
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Homework Statement



Let ϕn(x) be the complete ortho-normal set of eigenstates of the Hamiltonian H = T +V
and En, n = 0, 1, 2, are the corresponding eigenvalues. The E0 is the ground state energy.
(a) If ϕ(x) is an arbitrary normalized state, show that E0 < = ∫dxϕ(x)Hϕ(x).

(b) Consider one dimensional potential V0(x) = 0, abs|x| ≤ a/2 and = ∞ otherwise. The
second one dimensional potential V1(x) = (4V|x|)/a - V_0, |x|≤ a/2, V > 0 and = ∞otherwise.
If E0 and E1 are the ground state energies of the two potentials respectively. Find which
one (1) E0 < E1 (2) E0 > E1 is correct and prove your judgement.

Homework Equations



Schrodinger's Equation

The Attempt at a Solution



I think I have gotten part A correct. However, I am so confused at a non-square well potential. I know that the infinite potential boundary conditions still apply here, but it throws me off with what is going on inside the well.

Do I just do a normal solution of the T.I.S.E. and let my constant take care of the non-zero potential?

Any help is greatly appreciated.
 
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Wouldn't the answer depend on the value of V0? You can shift the value of E1 around by changing V0, but E0 is fixed.
 

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