← All parts of this equation

Equation 6 · Part 1 · The Corner of the Equivalence Principle No Experiment Has Touched

Symbol hateta

η^\hat\eta
η^\hat\eta

What this part means

hateta 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

hateta 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

…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, the paper argues, exactly five structurally distinct pieces fall out:

Read this part in the article →

Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

Open the illustrated variables: a letter stands for a value guide →

See this notation across published equations →

Sources cited in the surrounding passage

These citations provide research context; check each source for the exact claim it supports.