Equation 135 · Part 1 · The Clock That Comes Back Wrong by Exactly Its Mass
Symbol c
What this part means
c 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
c 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 c→Article meaning
The passage around this formula
There is a second, sharper constraint worth stating honestly rather than glossing over. Strict, exact Galilean invariance would forbid any coherent superposition of states with different mass eigenvalues outright — the Bargmann superselection rule, taken literally [ 1 ] . Every atomic clock ever operated superposes exactly such states, since an excited internal configuration carries strictly more rest mass than its ground configuration by E/ , and Ramsey-type coherence between them is measured routinely. This is not a contradiction; it is direct, everyday evidence that nature is Poincaré symmetric rather than exactly Galilei symmetric, with the superselection rule surviving only as…
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Sources cited in the surrounding passage
- [1] On Unitary Ray Representations of Continuous Groups ↗
- [5] Puzzling Out the Mass-Superselection Rule ↗
- [4] On Galilei Invariance in Quantum Mechanics and the Bargmann Superselection Rule ↗
These citations provide research context; check each source for the exact claim it supports.