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Equation 5 · Part 1 · A Reference Frame Becomes Classical by Publishing Its Orientation

Symbol J_z

JzJ_z
JzJ_z

What this part means

JzJ_z 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

JzJ_z 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

A laboratory description often begins with an unmentioned gift: an external frame. A Hamiltonian contains JzJ_z ; a detector sits at angle θ\theta ; a photon is called horizontally polarized. Those symbols presuppose an axis relative to which “z,” “angle,” and “horizontal” have meaning. Quantum-reference-frame research asks what happens when the object providing that axis is finite and quantum.

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the article section

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