This is another in the Pianist series. The dancers whirling dervishness calls forth a parallel universe. https://garyjkirkpatrick.com/pianist-singer-ballerina/ evoked that universe, causing the abstract incursion displayed on the rear wall. The additional energy produced by the dancers in this painting brought forth the more intense intrusion of a parallel universe.
Art meets string theory.
Or you can forget all that and just enjoy the contrast between the representative and the abstract, the muted values and the blaring values, the forms and motion, the unusual view from behind the performers.