Metal expands more than glass when both are heated. How can this fact be used to help open a metal screw top on a glass bottle which appears to be stuck?

A favorite method that usually works is to put the lid under running hot water for about 30 seconds. They also try to twist it off. This will heat up the metal lid and expand it more than the glass jar top. You also get a better grip by using a towel to grab the lid.