How do the windows around Hagia Sophia’s dome create the impression that it floats?

The impression that the dome of the Hagia Sophia floats on air is achieved through the strategic placement of windows. These windows pierce the curtain walls above the galleries and the base of the dome itself.12

When daylight enters through these openings, the glare obscures the structural supports—such as the great marble piers—that hold the dome in place. By masking these load-bearing elements with light, the architects created the visual effect that the massive canopy is suspended or floating rather than resting on solid masonry.12