Visual Art review: Treading fine line between something and nothing

CERITH WYN EVANS ***

INVERLEITH HOUSE, EDINBURGH

RONI HORN: 'THE TINIEST PIECE OF MIRROR IS ALWAYS THE WHOLE MIRROR' ****

THE COMMON GUILD, GLASGOW

TWO years ago, Cerith Wyn Evans exhibited an empty room at the ICA in London. To be more precise, he removed a false wall in an empty room which exposed the windows to the street.

There is a precedent for exhibiting empty rooms going back at least as far as Yves Klein, but Evans' work was about his personal relationship with the ICA, in particular a show he saw there by Marcel Broodthaers in 1975, which was crucial in his artistic formation. Now, he has taken the idea a step further by ripping out two fragments of wall from the ICA and exhibiting them attached to the wall of Inverleith House.

Works of this kind of conceptual minimalism tread a fine line between something and nothing. They might open up for you the blossoming possibilities of gallery walls – the walls at Inverleith House, for example, on which works by Douglas Gordon, Ian Hamilton Finlay, Robert Ryman and Richard Wright are still extant, under layers of white emulsion. Or it might leave you thinking nothing much, except possibly whether there are now holes in the wall at the ICA.

Evans is perhaps best known for his chandeliers, which illuminate messages in Morse code. One of these occupies the first room on Inverleith House's first floor. It is an immense wedding cake of a thing in Murano glass, slowly pulsing out text, which is deciphered by a nearby computer. What it reveals is not a great work of literature but a scientific text about astro-photography, illustrating that, though the idea of capturing the heavens is ambitious and poetic, the technical procedures involved are really quite tedious.

The next room is empty save for a speaker transmitting white noise. However, it all becomes more interesting when we learn that the sounds are recordings of signals from radio telescopes, devices capable of registering events billions of light years away. The idea that the whooshes and whines you are hearing might have been made millions of years ago will either give you a frisson of wonder or leave you wondering what all the fuss is about. It probably depends on your state of mind.

I didn't get a frisson of anything from Evans' film, A Film (I've been fooled by love), which is being shown in the basement. He started out as a film maker, and this is his first for some years, but it seems no more than a chopped-up selection of scenes from a Japanese porn movie manipulated in an editing suite and shown in endless sequence with a jaunty soundtrack by R&B singer Geno Washington. Apart from a crude juxtaposition of image and sound, I couldn't really see the point.

Evans uses two plants from the Botanic Garden in a final new work, Dear Lucifer, exhibiting them on mirrored plinths with a third left vacant to represent the "fallen angel". As spiritual symbolism goes, it's rather clumsy. The most interesting thing is the way the mirrors play off one another, offering a multi-fractured view of the room and the viewer.

Mirroring is a crucial component of the work of New York artist Roni Horn, currently on show at the Common Guild in Douglas Gordon's elegant townhouse in Woodlands Terrace. Indeed, for an artist fascinated by doubling and reflecting, it's a idea place to show: mirrors loom large in the otherwise minimal decor.

Horn was recently the subject of a major retrospective at Tate Modern and it would not be possible or appropriate to duplicate that show here. Curator Katrina Brown wisely plays to the strengths of the space and chooses work that suits the domestic scale, even if it means she has to omit the full scope of Horn's work, the concerns with landscape, water and weather, the long-term inspiration of Iceland.

The most striking work here is Gold Field, a sheet of 99.99 per cent pure gold hammered paper thin and laid on the floor of the upstairs lounge where the morning light from the bay window begins to fall across it. Horn's main concern is to draw our attention to the material, its preciousness, fragility, the extraordinary iridescent shade of orange with which it shines when it curves back on itself trapping light between the folds.

Also included is part of the series of photographs she created with actress Isabelle Huppert, Portrait of an Image. She photographed Huppert as herself, impersonating her various film roles, and the results are curious: naked emotion yet still veiled in the process of acting. Where is the real woman; who is really doing the looking? It's an artful way of illustrating the way Horn likes to leave her audience with more questions than answers.

Brown has chosen to include one of her pigment drawings, something Horn describes as "the primary activity". But a line is not a line to her; it is something she fragments and rearranges like a mathematical puzzle, or the pieces of a broken mirror. It is a process that she extends into her silkscreens and photocollages – Clownpout is an unsettling example of mirroring and fragmenting using a clown's face.

Horn's work is far from easy, yet it is imbued with a sense that it contains more than it reveals. It is beloved of writers – her Tate show was reviewed by both Jeanette Winterson and Kathleen Jamie – and is rich with literary references: Emily Dickinson is a favourite, and the title for this show comes from the Brazilian novelist Clarice Lispector. Its kernel is as elusive as the meaning of a poem, nor will it yield its riches easily, but there are hints that there may be gold here for those with the patience to dig.

&149 Cerith Wyn Evans until 5 July; Roni Horn until 4 July.