Inspired by acid trips, beautiful women, an old circus poster and more, The Beatles’ “Sgt. Pepper’s Lonely Hearts Club Band” shattered genre norms when it first came on the music scene on June 1, 1967, a full half-century ago. Today, after being certified 11x multi-platinum, The Beatles’ eighth studio album is one of the best-selling records in history.

Aside from topping charts, “Sgt. Pepper’s” introduced a new era in Beatles history — one where the Fab Four stepped away from their overwhelming fame and refused to tour, at least as themselves. As part of the concept album, The Beatles performed as a fictionalized Edwardian military brigade led by the character Sgt. Pepper. The album’s whimsy, both in concept and sound, made it a pioneer in the progressive and psychedelic rock genres as well as an anthem for the counterculture revolution.

But, after all this time, why are we still listening to songs like “Lucy in the Sky with Diamonds”? What does this album say about our musical and political past, and will it still hold up 100 years after its release? To answer those questions, Jordan Runtagh (@JordanRuntagh), the music editor at People Magazine and a contributor at Rolling Stone who recently went through “Sgt. Pepper’s” track by track — joined us for a Twitter chat June 2.

Read highlights from the chat below.