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Equation 4 · Part 1 · A Strained Crystal Is a Designer Spacetime

Symbol W

W(x)W(x)
WW

What this part means

W is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

W is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…statement as a single Hamiltonian, fixing the Fermi velocity vFv_F , the Pauli matrices σ\boldsymbol{\sigma} acting on the electron’s internal degree of freedom, the momentum-space shift b\mathbf{b} , and the tilt vector W(x) :

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Learn the underlying idea

A function assigns an output to each allowed input. The expression f(x) means “apply f to x”.

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Sources cited in the article section

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