The pop rocker recently hooked up with famed Los Angeles tattoo artist Dillon Forte for a super sick work of art stretching from Ben's left shoulder all the way down to his fingertips!!!

The sleeve's one cosmic creation -- it's inspired by a higher consciousness. What the hell does that mean? Well, smoke something if ya got it, and bear with us.

We're told the repeating pattern represents "the interconnectedness of all life and the unified field of vibrations resonating cosmic intelligence." Ummm ... puff, puff, pass?

Ben started his sleeve last year, and then decided he wanted the ink to run down to his fingertips. Remember, the universe is ever expanding -- so the musician sat down for a 4-hour sesh at Dillon's Sri Yantra Tattoo Studio in Venice.

Dillon's inked up tons of celebs with his super intricate artwork ... including Kat Von D, Chris Hemsworth and a head tattoo for Usher!

Ben's tat will definitely add another wrinkle to Imagine Dragons' already killer live shows. Just don't get lost in the cosmicness, dude.