Do gravitational waves stretch the wavelength of light?

We often get some version of this question:

If a gravitational wave stretches the distance between the LIGO mirrors, doesn’t it also stretch the wavelength of the laser light? If so, then how can LIGO detect gravitational waves?

This is a great question! Here are a few different resources for understanding the answer:

https://www.ligo.org/science/faq.php#mirror-distance

https://www.americanscientist.org/article/wavy-gravy

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