Yvonne Rainer, Threesome Review: Watching this electrifying performance for free feels like an enormous privilege | Art and design

AAt the back of the Turbine Hall, three people are dancing. If it weren’t for the vinyl dance floor and the white line separating her from the crowd, you might not realize it right away. You could be forgiven for thinking they were performing a distinct form of tai chi, or that they had taken a lot of drugs, if this were a different dance floor: one rolling on the floor, another extending his arms out, and a third diving in with his hips and touching his toes. Everyone seems so enamored with the actions of their bodies that they are oblivious to their partners on stage and the audience in front of them.

This being the Tate Modern on a Friday afternoon, this audience includes not only art school children dressed in the same casual costumes as the artists on stage, but also children screaming from prams and mischievous school children screaming from the mezzanine. None of this seemed to bother the dancers. After completing her routine, one of them steps away from the carpet and disappears through a door at the back of the hall. The others follow in their own time, and the audience applauds. After a short while, they are replaced on stage by a new trio of performers, and the dance begins again.

Yvonne Rainer’s Triple A is among the most influential works of art to emerge from that remarkable period in New York’s cultural history from the mid-1950s to the mid-1970s. The show at the Tate marks the 60th anniversary of his first concert, when Reiner (who continues to teach new dancers in the work), along with David Gordon and Steve Paxton, marked a revolutionary moment in dance as an art form. The reasons for this are tedious to describe – it introduced everyday movements into the choreography, stripping the dance of its traditional theatricality – but quietly exciting to observe.

Each performance lasts about five minutes, and if you join in halfway through, you might initially think the dancers were improvising, so naturally each pose follows from the last. It may only take a second viewing before you realize that not only are the dancers following a strict choreography, but each other’s own as well same Choreography. It’s just that when you do it at their own pace, they quickly get out of sync. Part of what makes Trio A so compelling to watch is that each performer is licensed to execute the poses at the tempo they feel is most appropriate for them, which means some hold the pose a little longer or move more quickly during certain transitions. There is no need to coordinate this rhythm, so the peculiarities appear in the different performances performed by dancers of different ages and body types.

Rainer’s innovation was to remove psychodrama from dance by insisting that the performers ignore the audience and each other. So you get three people executing a set of precise instructions for no one’s benefit but their own. This dancer is weak, and that dancer is fickle; Her expressions are more specific, his expressions more lyrical. I’m reminded of those 18th-century paintings that depict the sitter absorbed in an activity—playing the guitar, for example, or reading a book—rather than looking to meet the viewer’s gaze. Defining us by our inner lives rather than by our appearance in the eyes of others is a fundamentally modern idea. Rainer extends this principle to dance. These dancers aren’t performing for you, but that doesn’t make them any less compelling to watch.

Instead, the experience is hypnotic, especially with the benefit of repeated viewings afforded by Tate’s decision to present it as a repeated performance over several hours each day. Movement in the choreography is evenly distributed: no position carries more weight than another, there is no sense of climax or relaxation in lulls, there is triumph or tragedy. In this respect it is reminiscent of some of the more ecstatic music of Philip Glass, another great artist emerging from the New York scene of the period.

Simply observing highly trained humans fully concentrate on executing a set of physical instructions, with varying degrees of precision and elegance, feels like a privilege. It is a matter of pride that this should be freely available to anyone in London who has a few moments of time, without having to pay the exorbitant entrance fees that turn museums elsewhere into entertainment centers for the rich. For the two hours I was there, the audience moved back and forth as the dancers moved and changed. It seems appropriate for business that the dancers are allowed to continue their solo work, with the world revolving around them.