Laser excitation of Th-229 nucleus

Big discussion from another URL https://news.ycombinator.com/item?id=40194636 (405 points | 18 hours ago | 177 comments)

“New findings suggest classical quantum physics and nuclear physics can be combined”

Seems like the bigger part of the title

what does it mean for a nucleus to be in a higher energy state? is there any macro phenomenon that is related to it? when it drops back down, it gives off a gamma ray or something?

https://en.wikipedia.org/wiki/Nuclear_isomer

In some cases, one configuration of the nucleus is football-shaped, and there's an energy difference between that and the round shape. In other cases, a set of two protons and two neutrons will be jolted loose from the rest of the nucleus, and sort of orbit around it.

HTTP 404 now, but it's still linked from the site's "Physics" category page, so it's not a typo...