Having systematically picked apart the critical arguments for and against Christopher Nolan‘s film “Inception” and the many possible meanings of that dream-within-a-dream-within-a-dream caper, the Web this week went another level into the movie by focusing on its music.

In recent days Internet denizens have gotten very excited about a viral video (posted above) that compares the Édith Piaf song “Non, je ne Regrette Rien” to Hans Zimmer‘s score for the movie. When the video’s pseudonymous author, camiam321, plays the key musical cue from that score, two ominous blares from a brass section, followed by a slowed-down version of the Piaf song (which the “Inception” characters play at regular speed as a warning to wake up from a dream state), they sound nearly identical.

In a telephone interview Mr. Zimmer, a film composer and producer who won an Academy Award for his music for “The Lion King” and was nominated for films including “Rain Man” and “Gladiator,” said the sonic similarity was not only intentional but also the one element of an enigmatic movie “that wasn’t supposed to be a secret.”

Speaking of the viral video, Mr. Zimmer excitedly said: “I’ve seen it. I’ve seen it. I was surprised how long it took them to figure it out.”

The musical cue, Mr. Zimmer said, “was our big signpost” in the film of its characters’ moving from one level of dreaming (or reality) into another. “It was like a drawing of a huge finger,” he said, “saying, O.K., different time.”

Mr. Zimmer said the idea for this musical game had begun with Mr. Nolan, the film’s director and writer.

“He had the Édith Piaf always written in the script, the ‘da-da, da-da,’ ” he said, imitating the cadence of that song. “It was like huge foghorns over a city, and afterward you would maybe figure out that they were related.”

Technically, Mr. Zimmer said, his score is not a slowing-down of the French song, which was composed by Charles Dumont and recorded by Piaf in 1960, but is constructed from a single manipulated beat from it.

“I had to go and extract these two notes out of a recording,” Mr. Zimmer said, using a little bit of “Inception” lingo. “I love technology, so it was a lot of fun for me to go and get the original master out of the French national archives. And then find some crazy scientist in France who would actually go and take that one cell out of the DNA.”

“Just for the game of it,” Mr. Zimmer said, “all the music in the score is subdivisions and multiplications of the tempo of the Édith Piaf track. So I could slip into half-time; I could slip into a third of a time. Anything could go anywhere. At any moment I could drop into a different level of time.”

In this sense, the score is Mr. Zimmer’s personal interpretation of “Inception,” which many viewers have read as a commentary on the nebulous boundary between dreaming and reality.

“Everybody thinks the dream is the important part,” Mr. Zimmer said. “For me, the time was the important part: the idea that, in a peculiar way, Chris had made a time-travel movie that actually worked.”

Mr. Zimmer, who in 2008 was briefly excluded from an Oscar nomination for the score to “The Dark Knight,” which was deemed to have had too many composers (the Academy of Motion Picture Arts and Sciences eventually reversed itself and allowed him and a co-composer, James Newton Howard, to compete for the award), said he had no idea how awards bodies would react to his “Inception” score’s incorporation of the Piaf track.

“I didn’t use the song; I only used one note,” Mr. Zimmer said. “But look, I so couldn’t care less about awards. I know I’m not supposed to say this. But when you work with Chris Nolan, when you work on a movie like ‘Inception,’ it’s for the adventure.”