The landmark projects of the London Design Festival use light to explain architectural history

Halo by Moritz Waldemeyer at the London Design Festival 2023

Less known than Saint Paul's, the Church of St Stephen Walbrook designed by Sir Christopher Wren is a decidedly intimate and precious space. Architecturally, a sort of dress rehearsal for St Paul's given that it is here that Sir Christopher Wren tested for the first time an alternative way of building a dome: positioning the base not on a square but on a circle, developed in height through 8 arches supported on 12 columns.

In Halo, a kinetic and meditative work in which algorithms and digital light mix with poetry, architecture and art, Moritz Waldemeyer celebrates all the greatness of Sir Christopher Wren: who was an architect but also an astronomer, a mathematician and a physicist.

Halo is a flattened-shaped brass pendulum hanging from the lantern of the church dome thanks to a 20-metre invisible wire. Above the saucer-shaped base is a strip of LEDs programmed to send light up and down the pendulum: the light is perfectly synchronized to follow the path of a tilted halo as it rotates.

The pendulum therefore oscillates a few centimeters from the edge of the travertine marble altar sculpted by Henry Moore and the light sways together with it according to a movement that is at the same time circular, around the round altar, and vertical, that is, along the cable.

If you observe the movement of the pendulum with a long exposure camera, for 10s, the light leaves a luminous trail in space which creates a halo (hence the name).

“The pendulum is inspired by experiments conducted by Sir Christopher Wren, who was also a great astronomer,” explains Moritz Waldemeyer whom we met on the occasion of the inauguration of the installation at the London Design Festival.

“It is also made of brass, a material Wren would recognize, is operated manually, as he would have done, and is subjected to the same physical stresses and restrictions, then spiraling inwards very slowly over time due to air friction. Every now and then it has to be reactivated, which transforms the installation into a performance”.

Observing Halo is therefore an almost meditative experience, enriched by the presence of projections on the dome, "inspired by cosmic phenomena that fascinated Christopher Wren, who was also an astronomer", concludes Waldemeyer. But also an opportunity to discover the thoughts of Sir Christopher Wren and his poetics, in a non-didactic way

Aura by Pablo Valbuena

Aura is a long, narrow aluminum structure, which runs through the heart of St Paul's Cathedral – where services take place – from top to bottom, hanging from the center of the huge dome.

Aura is like a spear covered in LEDs. A cut in space which, thanks to an algorithm, lights up when the LEDs interpret the sounds of the Cathedral, transforming them into light signals, varying in intensity depending on the frequencies.

We observed it at the best moment: during a religious function, when the singing of the choristers, the sound of the organ and the voice of the priest fill the vaults, the naves, the dome itself, a jewel of knowledge Wren's architectural making.

You can feel the result on your skin and in your heart: and it leaves you astonished with its subtle grandeur, present but not shouted out.

“To get the 100 kilos of Aura up there it was necessary to assemble it directly on the supporting wire”, explains Pablo Valbuena. “It was done by some very brave kids, who climbed the architectural structures with harnesses, like mountaineers”

Aura is very striking because it is a visual transposition of the ritual

To create it, in fact, Valbuena was inspired - as well as by Wren's architecture - also by the interpretation of the rites carried out by the philosopher Byung Chul-Han: "the rituals they are to time as housing is to space, they make time habitable”.

Aura therefore perceptually intensifies the ritual and symbolic dimension of the space of St Paul's - already grandiose and immersive by its nature - and adds the element of time to the equation, making it visual and present.

After seeing the two landmark projects of the London Design Festival, suddenly Sir Christopher Wren's famous phrase ("light is God's greatest gift to Man") suddenly acquires more meaning and value even in contemporary times.