E=MC² is the eleventh studio album by American singer-songwriter Mariah Carey. It was released in the United States on April 15, 2008 by Island Records. The singer began recording the album in 2007 in Anguilla, after writing and composing most of its material during and after her 2006 Adventures of Mimi Tour. Carey worked with several notable songwriters and producers during the course of the project, including Jermaine Dupri, Bryan-Michael Cox, Stargate, The-Dream, Tricky Stewart, Scott Storch and Danja.
The album revealed a more personal and intimate side of the singer, illustrated in its declarative theme of emancipation from her previous marriage, and from her personal and professional setbacks. Although it shared similar vocal production as well as an inclination to her signature pop and R&B ballads, the album also encompassed a variety of dance-oriented and uptempo styles. It was meant to be a continuation, or a second part of her tenth studio album, The Emancipation of Mimi (2005). Carey collaborated with a number of artists on the album, including T-Pain, Damian Marley and Young Jeezy. Though considered by critics very similar to the formula its predecessor had been built on, E=MC² included other genres she had never explored, such as reggae, and her continued recording of gospel-influenced hymns.
E=MC² was generally well received by music critics, with many complimenting the record's broad genre influences, and musical and production styles. Some critics, however, felt that the album was too similar to The Emancipation of Mimi, and didn't offer anything new from the formula. The album debuted at number one on the US Billboard 200 with opening week sales of 463,000 copies; the highest first-week sales of Carey's career. It opened inside the top-five on the albums chart in Australia, Canada, Switzerland and the United Kingdom. The album achieved worldwide sales of over 2.5 million copies worldwide.
Four singles were commission in promotion of the album. The album's lead single, "Touch My Body", became Carey's eighteenth chart topper on the Billboard Hot 100, making her the solo artist with the most number one singles in United States history, surpassing the record held by Elvis Presley. Additionally, it gave Carey her 79th week atop the chart, tying Presley for most weeks at number one. It achieved strong worldwide charting, peaking within the top five of the singles charts in Italy, Japan, New Zealand, Switzerland and the United Kingdom. "Bye Bye" served as the album's second release. Although hailed by critics, and expected to have achieved large commercial success, the song stalled at number nineteen on the Hot 100, and managed to chart weakly internationally. Both the third and fourth singles, "I'll Be Lovin' U Long Time" and "I Stay in Love" failed to garner success in any prominent music market.