Questions tagged [operators]
Questions about using or composing operators--functional mappings from one state or vector space to another.
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Clebsch–Gordan coefficient calculation for L-S basis in system of three particles
I am trying to calculate eq (A3)
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2
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1
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83
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General solution of a differential equation
I'm a beginner in Mathematica and I'm learning about dealing with differential equations but I'm stuck in this problem
What I tried to do is I observed that I have the same differential operator ...
9
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1
answer
181
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List[...] + Association[...], or Association[...] + List[...], when does the order matter?
Values of a list can be added to an association's values like so,
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70
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How to define a composition of operators?
If I define P[x]=D[#,x]& (derivative operator)
How can I define another operator $Q$ such that $Q(f(x))=Pf(x)+a$ (for example)?
Thanks.
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46
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Taking sums of differential operators
If I define a differential operator:
T[i_] := D[#, x[i]] &
I am able to apply it multiple times to a function without any issues:
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3
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3
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205
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Finite Differences:
I am having difficulty implementing finite differences in the correct columns of my code.
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2
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1
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Defining custom operators for indexed objects [closed]
I have some symbolic indexed objects $A_i$, $B_{ij}$, $C_{ijk}$, $D_{ijkl}$, etc.
I want to define a symbolic differential operator $\partial_{xy}$ that acts on these indexed objects in the following ...
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6
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Applying several functions to the same argument
Is there a more concise way of achieving the following result (possibly without d |->)?
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How to define the square root of an operator [duplicate]
How can I define the operator $\sqrt{m^2-\frac{\partial^2}{\partial x^2}}$, such that it acts on the function $\psi(x)$ as follows: \begin{eqnarray*}
\sqrt{m^2-\frac{\partial^2}{\partial x^2}}\...
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3
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Apply central difference formula to a variable twice
I am working with finite difference methods analytically and I would like to be able to perform operations on subscripted variables.
I would like to generate the following expression by applying a ...
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3
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273
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How can I construct a determinant-type differential operator?
How can I construct a determinant-type differential operator, where the multiplication of elements in the determinant represents the composition of multiple differential operators?
\begin{align*}
\...
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Nested RowBox in MakeExpression reports error when I define my own curl operator, but the single RowBox in MakeExpression works well
I want to define my own vector notation so that the input \[Del] \[Cross] a outputs curl[a] while the ...
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Doing algebra with differential operators
I'm doing some work on stochastic processes, where I use random functions which are defined by their properties over averages, i.e $$\langle f(t) \rangle =0 \\ \langle f(t) f(t')\rangle = \alpha(x,y) ...
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Could Mathematica analytically work with operators (such as $\nabla$) and vectors?
I have the following expression: $$(\nabla+\vec{P})^2$$
where $P=(r\cos\theta sin\phi,r^4\sin\theta,r\cos^3\phi)$
I would like to open the brackets and simplify the expression.
Are there in ...
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