In the 1950s, an iconoclastic quantum scientist and mathematician named Hugh Everett developed the many-worlds theory, a controversial idea that would lay the groundwork for a canon of alternate universe sci-fi detailing parallel dimensions.Hugh Everett’s work focused on the splits in the universe caused by measuring quantum objects, but became fodder for the idea that alternate realities besides our own are forming continually. I don’t know how many people in the audience at Wednesday night’s Amazon Music concert at New York’s Hammerstein Ballroom have nerded out on Everett’s theory, but a bastardised version played out as Taylor Swift brought her stadium show to a far more intimate gathering to promote the site’s Prime Day next week.In one universe, singer and songwriter Taylor Swift the consummate businesswoman has been publicly airing out her grievances over music manager Scooter Braun’s purchase of her former record label Big Machine and, subsequently, the master recordings for her first six albums. “This is my worst case scenario,” she wrote late last month on Tumblr. “All I could think about was the incessant, manipulative bullying I’ve received at Braun’s hands for years.” It’s the closest the music industry has had to a hot war in a while, with pop stars taking sides in Braun vs Swift like it’s the last two minutes of Michael Jackson’s “Beat It” video. In one sense, it’s very inside baseball, with “industry insiders,” shadowy cabals of kingmakers and the rest of the music industry all watching a typically backroom deal play out in a public setting. In another, it has led, softly, to a wider discussion about an author’s ownership of their own music that is only beginning to reverberate.In Wednesday night’s alternate universe, though, royalty rates, deal points, masters ownership and the like did not exist, as Swift’s nine-song, 45-minute set eschewed the recent dirty laundry to focus on fan favourites that blended the intimate with the spectacle. Heavy is the head that wears the gown. But Swift knew why her fans were there. While the night’s other performers Dua Lipa, SZA and Becky G all admirably welcomed the intimacy afforded the venue – a H-shaped stage that extended to the middle of the floor made a relatively small space look even smaller – Swift brought her massive stadium show to a diminished setting. Opener “Me!” featured pyrotechnics that augmented her four back-up singers. Steam machines exploded out on “I Knew You Were Trouble.” And “Shake It Off” featured inordinate amounts of confetti raining down on the shrieking crowd.This was Swift’s evening; an easy victory on her promo tour for next month’s release of ‘Lover’. Who knows if she publicly escalates her battle with Braun and Big Machine CEO Scott Borchetta in the run-up to ‘Lover’. But tonight was Taylor Swift as uncontroversial superstar and for an adoring crowd, that was all that was neededIt was hardly all pyro and fireworks, though. Swift utilized the rare small stage to perform “Welcome to New York” with only an acoustic guitar. It’s not unprecedented for her, but seeing it in a venue 1/10th the size of what she’s used to is the closest most of us will get to a Taylor Swift: Unplugged concert.Still, you never forgot why you were there. Thanks to 360-degree wallpapering, a giant screen in the middle of the stage showcasing their latest shows, and random actors coming out between sets to hype up Prime, Amazon made sure you knew that mom and dad were paying for this party. Call it Amazon’s “superliminal” approach to marketing. This is the first show I’ve ever seen in which the crowd exuberantly cheered the phrase “free shipping,” as “Academy Award-watching actress” Jane Lynch genially kept the night moving.The night did not solely belong to Swift. Dua Lipa continues to be a more powerful force on record than onstage, slithering through “Blow Your Mind,” “One Kiss” “Electricity” and “IDGAF” with robotic-chic choreography that’s either sophisticated cool or bored insouciance. The Amazon machine is strong, as the singer opened the last song of her 20-minute set with “Alexa, play ‘New Rules.'”Becky G showed a confidence and charisma onstage that shows the 22-year-old singer coming into her own. Flanked by a half-dozen dancers, the California native breezed though a set that included “Dollar,” “Mayores” and “Sin Pijama” and was warmly received by the Taylor-dominant crowd. SZA proved her 2017 debut album CTRL still has legs, performing “Supermodel,” “Broken Clocks” and “Love Galore” alongside her tour staple cover of Sixpence None the Richer’s “Kiss Me.”But this was Swift’s evening; an easy victory on her promo tour for next month’s release of Lover. Who knows if she publicly escalates her battle with Braun and Big Machine CEO Scott Borchetta in the run-up to Lover. But tonight was Taylor Swift as uncontroversial superstar; and for an adoring crowd, that was all that was needed.