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Equation 2 · Part 1 · The Corner of the Equivalence Principle No Experiment Has Touched

Symbol hat M

M^\hat M
M^\hat M

What this part means

the call it.

Its job in the formula

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

Where the article explains it

Model that operator, call it M^\hat M , as M^\hat M = m(1 + H^int\hat H_{int}/mc2c^2) , where H^int\hat H_{int} is the system’s internal Hamiltonian, and let the gravitational mass be mgm_g = mi(1+η^)m_i(1 + \hat\eta) for some violation operator η^\hat\eta acting on the internal, and for two-body tests the joint, Hilbert space.

The passage around this formula

…but an operator, and equivalence has to be stated as equivalence between its rest, inertial, and gravitational internal-energy operators rather than between their average values [ 1 ] . Model that operator, call it M^\hat M , as M^\hat M = m(1 + H^int\hat H_{int}/mc2c^2) , where H^int\hat H_{int} is the system’s internal Hamiltonian, and let the gravitational mass be mgm_g = mi(1+η^)m_i(1 + \hat\eta) for some violation operator η^\hat\eta acting on the internal, and for two-body tests the joint, Hilbert space. Expand that operator and,…

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Sources cited in the surrounding passage

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