A sudden change in the depth of delta function potential well

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The discussion centers on the implications of changing the depth of a delta function potential well on continuum and bound states. It posits that continuum states will behave as free particle states, with the probability of transition calculated as |<Ψf | ΨB>|^2. The participants explore the relationship between old and new bound states, specifically |BS_A> and |BS_B>, to derive the probability of transfer to unbound states as 1 - ||^2. There is a debate on whether the relative magnitudes of the depths A and B affect the transition probabilities, suggesting that the well's depth changes may not significantly impact the outcomes. The conversation highlights the complexities of quantum state transitions in response to potential well modifications.
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Homework Statement
If a particle is initially in the bound state of a delta function potential well, having depth A, and at some point in time the depth suddenly changes to B. What is the probability that the particle will now be in the states of the continuum spectrum? both A and B are greater than zero.
Relevant Equations
equations are attached.
is it correct that the continuum states will be free particle states? and the probability will be |< Ψf | ΨB>|^2 . Where Ψf is the wave function for free particle and ΨB is the wave function for the bound state when the depth is B.
 

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Because we are well aware of the old and new bound states ##|BS_A>## and ##|BS_B>##, we can calculate
1-|&lt;BS_A|BS_B&gt;|^2
and I assume it as probability of transfer to unbound states.
I wonder it says relative magnitude of A and B, so deepening or shallowing of well, does not matter. Maybe I am wrong.
 
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The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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