Songfacts®:

• This dance-floor ballad finds Lady Gaga singing about the power of music. Titled after the shape of sound waves - sine curves – it finds the Mother Monster extolling music's healing properties. She told Apple Music's Zane Lowe: "That sound, sine, from above is what healed me to be able to dance my way out of this album. That was later in the recording process that I actually was like, 'And now let me pay tribute to the very thing that has revived me, and that is music.'"
• Sir Elton John joins Lady Gaga on the song, marking the second collaboration between the pair. They previously recorded a tune together for the soundtrack of the 2011 animated film Gnomeo & Juliet titled "Hello, Hello."
• Gaga and John are good friends and have shared the stage several times, including performing a fusion of their respective hits "Your Song" and "Speechless" during the 2010 Grammy Awards. She described him to Zane Lowe as her "mentor" and explained how the British star played a significant role in her road to recovery from past traumas. "He's always challenged me to keep my head above water and it's something that I always appreciate is that he knows when I'm down," she said.