← All parts of this equation

Equation 142 · Part 1 · The Bit Comes Back Before the Bearing

Symbol epsilon

ϵ\epsilon
ϵ\epsilon

What this part means

the depend on a joint choice of.

Its job in the formula

epsilon 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

It does, however, depend on a joint choice of ϵ\epsilon and δ\delta that this article has no privileged way to fix, and for a sufficiently coarse compass paired with a sufficiently strict qubit fidelity, the ordering in the title simply does not hold.

The passage around this formula

…— each is anchored to a cited, checkable piece of theory, and the crossover tolerance δ∗\delta^\ast is computed, not chosen after the fact to produce a headline. What is a choice, and should be named as one, is treating ϵ\epsilon and δ\delta as commensurate just because both are dimensionless numbers between zero and one. A fidelity and a normalized angular tolerance measure different things, and no law of physics says a “demanding” qubit fidelity and a “demanding” compass tolerance sit at the same point on their…

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 article section

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