# Why does relativity allow quantum tunnelling to ‘take no time’?

@article{Sokolovski2004WhyDR, title={Why does relativity allow quantum tunnelling to ‘take no time’?}, author={Dmitri Sokolovski}, journal={Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences}, year={2004}, volume={460}, pages={499 - 506} }

In quantum tunnelling, what appears to be an infinitely fast barrier traversal can be explained in terms of an Aharonov–like weak measurement of the tunnelling time, in which the role of the pointer is played by the particle's own coordinate. A relativistic wave packet is shown to be reshaped through a series of subluminal shifts which together produce an anomalous ‘superluminal’ result.

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