Physical observables in a gauge theory$^1$ are independent of gauge-fixing choices$^1$. Conversely, gauge-fixing choices are unphysical.

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$^1$ Here we have applied the narrow definition of a gauge theory where gauge symmetry represent a redundant description of a physical system, cf. e.g. this Phys.SE question. In other words, we have ignored gauge transformations that actually change the physical configuration, cf. answer by tparker.

$^2$ By a gauge-fixing condition, we assume a condition that intersect each gauge-orbit precisely once. Note that some conditions do not actually fulfill this, e.g. only partially fixes a gauge. Also there might be a Gribov problem.

Physical observables in a gauge theory$^1$ are independent of gauge-fixing choices$^1$. Conversely, gauge-fixing choices are unphysical.

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$^1$ Here we have applied a narrow definition of a gauge theory where gauge symmetry represents a redundant description of a physical system, cf. e.g. this Phys.SE question. In other words, we have ignored (large) gauge transformations that actually change the physical configuration, cf. answer by tparker.

$^2$ By a gauge-fixing condition, we assume a condition that intersect each gauge-orbit precisely once. Note that some conditions do not actually fulfill this, e.g. only partially fixes a gauge. Also there might be Gribov problems.

Physical observables in a gauge theory are independent of gauge-fixing choices. Conversely, gauge-fixing choices are unphysical.

Physical observables in a gauge theory$^1$ are independent of gauge-fixing choices$^1$. Conversely, gauge-fixing choices are unphysical.

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$^1$ Here we have applied the narrow definition of a gauge theory where gauge symmetry represent a redundant description of a physical system, cf. e.g. this Phys.SE question. In other words, we have ignored gauge transformations that actually change the physical configuration, cf. answer by tparker.

$^2$ By a gauge-fixing condition, we assume a condition that intersect each gauge-orbit precisely once. Note that some conditions do not actually fulfill this, e.g. only partially fixes a gauge. Also there might be a Gribov problem.