Equation 22 · Part 1 · The Corner of the Equivalence Principle No Experiment Has Touched
Symbol eta_cl
What this part means
the these bound a combination of.
Its job in the formula
etl is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol eta_cl→Article meaning
Where the article explains it
Because rubidium and potassium differ in composition rather than internal quantum state, these bound a combination of and , not the coherence or entanglement pieces.
The passage around this formula
Lay all of it out in one table, rows for experiments and columns for the five components, and four columns get real entries: constrained at the 10^{-15} level by MICROSCOPE, constrained by every dual-species and clock test in the list, constrained at the low- 10^{-9} level by Rosi and colleagues’ internal-superposition test, constrained by Overstreet and colleagues’…
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
- [5] Quantum Test of the Universality of Free Fall ↗
- [6] Quantum test of the Universality of Free Fall using rubidium and potassium ↗
- [4] Atom-Interferometric Test of the Equivalence Principle at the 10⁻¹² Level ↗
- [7] Quantum test of the equivalence principle for atoms in superpositions of internal energy eigenstates ↗
- [10] Observation of a gravitational Aharonov-Bohm effect ↗
These citations provide research context; check each source for the exact claim it supports.