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Equation 134 · Part 2 · The Clock That Comes Back Wrong by Exactly Its Mass

Symbol c^2

ΔE/c2\Delta E/c^2
c2c^2

What this part means

The square of c: multiply c by itself.

Its job in the formula

c2c^2 is squared: multiply the underlying quantity by itself. The square is a mathematical operation, not a second independent variable.

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 Δ\Delta E/c2c^2 , 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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Learn the underlying idea

An exponent tells how a base is used in multiplication. In x³, x is the base and 3 is the exponent: x³ = x × x × x.

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Sources cited in the surrounding passage

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