  Noether's theorem is one of the fundamental laws of physics, relating
continuous symmetries and conserved currents. Here we explore the role of
Noether's theorem at the deconfined quantum critical point (DQCP), which is the
quantum phase transition beyond the Landau-Ginzburg-Wilson paradigm. It was
expected that a larger continuous symmetry could emerge at the DQCP, which, if
true, should lead to emerged conserved current at low energy. By identifying
the emergent current fluctuation in the spin excitation spectra, we can
quantitatively study the current-current correlation in large-scale quantum
Monte Carlo simulations. Our results reveal the conservation of the emergent
current, as signified by the vanishing anomalous dimension of the current
operator, and hence provide supporting evidence for the emergent symmetry at
the DQCP. Our study demonstrates an elegant yet practical approach to detect
emergent symmetry by probing the spin excitations, which could potentially
guide the ongoing experimental search for DQCP in quantum magnets.
