When you're a musician talking about another musician, even the slightest tinder of a comment can start a brushfire that's re-ignitable by the merest Google search. It doesn't matter whether it's outright criticism or just a void where the diss would go. The world wants feuds, and by golly, it will have them. Case in point: Swedish pop star Robyn, opening for Katy Perry's California Dreams tour, made this giggly/pointed comment in a Time Out interview:

You’re opening for Katy Perry this summer—how did that happen?

I was asked by her to do it and thought it was a good way of getting to know her audience. It’s bigger than mine. [Laughs]

And are you a fan of hers?

You know what? I have to go now. [Giggles]

As disses go, this one's pretty wink-wink, but fans and haters alike interpreted it the same way: Robyn and Katy Perry have beef. Potentially tour-trampling beef. When Nicki Minaj passing on Britney's European tour dates can get U.S. sites in a tizzy, you can imagine how much of a problem this could be, enough that Robyn had to shoot the rumors down in a mea non culpa MTV interview:

"I think that girls are always expected to have opinions about each other, and maybe I don't have an opinion about some things, you know? ... We're always expected to have thoughts about what the other person is doing, and I think that's silly. You very rarely get asked about another guy as a male artist."

She's got a point: while male artists certainly raise beef and ignite fan wars, rarely do they rise to the no-explanation-needed level of Britney vs. Christina or, this year, Adele vs. anybody else. But there's more to the Katy Perry/Robyn un-feud that makes it so plausible at first: the idea of authenticity.

There are the surface arguments, of course. Robyn's a left-field alternative pop star (who used to be a mainstream pop star, but nobody brings that up in these arguments) with an asymmetric haircut and boyish look; Katy Perry's fully mainstream and fully enhanced with pinup makeup. Robyn's sung about sex in "Hang with Me," but to our knowledge, whipped cream's never been shot out of any part of her costume. Robyn's videos find her awkwardly punching the air; Katy's have her lying nude on top of clouds.

More generally, Robyn's hits--particularly in the Body Talk era--are largely about championing the outsiders. She's often the spurned lover, on "Be Mine," or her Royksopp collaboration "The Girl and the Robot," or especially her biggest hit this cycle, "Dancing on My Own." Even steelier songs like "Indestructible" have an underdog narrative built in. All Robyn's strength, in other words, is forged from solitude, blows and sheer don't-give-a-fuck. Meanwhile, if Katy Perry mentions the outsider at all, it's to toss them a nerd stereotype and sticks a hundred punchlines into it like pushpins.

Take a closer look at the two artists, however, and things get more complicated. The "artificial" argument, for instance, falls apart like cheap polyester. There's plenty of processing on Robyn's voice, then and now; meanwhile, Katy Perry claims not to use Autotune, and even on studio recordings, her vocals tend toward the gruff. Katy Perry's singles are built from the latest, most ubiquitous sounds in Dr. Luke and Max Martin's everpresent production catalog--"California Gurls" sounds like "TiK ToK" and so forth--but Robyn's just mining a slightly different quarry of dance beats, and she's got plenty of Max Martin in her repertoire anyway. Take "Show Me Love," 100% a relic of its time:

And even if "sexy" equaled "fake" (it doesn't), Robyn and Katy's musical personalities and subject matter are quite similar. Both artists deliver their songs with a light, slightly cheesy wink--and both have had to fend off accusations of being too cutesy. Robyn's "Fembot," for instance, is precisely the sort of cheeky, gimmicky song Katy Perry loves--if the Swedish singer hadn't laid claim to lines like "I've got a lotta automatic booty applications" or "I'm a very scientifically advanced hot mama," Perry could well have sung them a few years down the line, perhaps complete with a video where she's a spark-shooting femdroid or Snoop Dogg's robot pal. (Robyn's got a Snoop collaboration too, incidentally.)

And both Robyn and Katy, at their best, excel at the same thing: cavernous pop songs that are louder than life. In the MTV interview, Robyn called the pre-chorus of "Teenage Dream" "amazing" and said that she wished she wrote it herself. It's a perfect example: not only is "Teenage Dream" Katy's best song by far, but it makes love, teenage or otherwise, sound just this side of epic, realer than life. "Dancing on My Own" does the same thing.

So it shouldn't be that surprising that the singers of two of 2010's biggest songs are touring together. All these similarities, in a way, are beside the point. Katy's a fan of Robyn's work, Robyn's a fan of at least some of Katy's work, and anyone listening can be a fan of both, either or neither. There's no need to argue about who's "real" and who's "fake"--the only thing fake is the distinction.