Finding general expression for probability current.

David Silva
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The conservation of probability says:

$$\partial_t J^{0} + \partial{i}J^{i} = 0$$

Use the Schrodinger equation to obtain$$ J^{i} (\vec r)$$.

I have no idea where to start this kind of problem because the notation makes no sense to me. I would appreciate a hint or nudge in the correct direction.
 
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What about the notation confuses you?
 
vela said:
What about the notation confuses you?
What do those partials mean? I am not used to seeing them this way? Also would I be using the general SE eq or the radial one since we are in r?
 
Typically ##x^0 = t##, ##x^1 = x##, ##x^2 = y##, and ##x^3 = z##, so ##\partial_1## would mean ##\partial_x##. The repeated index ##i## implies a summation from ##i=1## to ##i=3##.

You have ##J^\mu = (\rho,J_x, J_y, J_z)##, so in more traditional notation, conservation of probability is
$$\frac{\partial \rho}{\partial t} + \nabla \cdot \vec{j} = 0$$ where ##\vec{j} = (J_x, J_y, J_z)##.
 
vela said:
Typically ##x^0 = t##, ##x^1 = x##, ##x^2 = y##, and ##x^3 = z##, so ##\partial_1## would mean ##\partial_x##. The repeated index ##i## implies a summation from ##i=1## to ##i=3##.

You have ##J^\mu = (\rho,J_x, J_y, J_z)##, so in more traditional notation, conservation of probability is
$$\frac{\partial \rho}{\partial t} + \nabla \cdot \vec{j} = 0$$ where ##\vec{j} = (J_x, J_y, J_z)##.

Thanks, I will look at this later today and see if it helps!
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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