Some twenty-five years ago Marc Weiser set out a vision of the computer for our twenty-first century. He imagined technology integrated "seamlessly into the world at large"; "hundreds" of processors, screens, boards and tablets, all networked and interacting, woven into the everyday details of our life, responsive to our voices and gestures. Many of the technical details of Weiser’s vision of ubiquitous computing were prescient: wireless networks, tablet computers, voice interfaces. But his ideas also describe a powerful vision of a relationship between human technology and the environment. For Weiser the human environment becomes technological, populated with systems that answer our whims and support our work. This technology will be less frustrating, more "calm" — more like our experience of the natural world: "Machines that fit the human environment ... will make using a computer as refreshing as taking a walk in the woods."

Our computers are certainly ubiquitous; and technologists continue to offer us visions of seamless integration, voice command and virtual assistants. As well as fragmenting into more and smaller devices, our digital lives have moved to the connective atmosphere of the "cloud", hovering everywhere and nowhere at all times. Yet for all this ubiquity, we seem as un-calm as ever. For one thing, it seems that our digital environment is less a walk in the forest, more a cryptic underworld. In October 2016 large sections of the internet were rendered unusable by attackers who took over thousands of networked devices — mainly video recorders and security cameras. For another, we’re increasingly aware that this "cloud" is not exactly nowhere; it’s just in someone else’s computer. The massive data-centers that run the cloud suck terrifying amounts of power; they emit as much carbon as the global aviation industry. As Benjamin Bratton argues, our digital infrastructure has reached planetary scale. It may be that as it continues to grow it makes the planet unlivable, and not just for humans. Marc Andreesen declared in 2011 that software was "eating the world"; this is more than just a figure of speech.

So in the swirling, intractable mix of anxieties and crises that we swim through now, this axis between technology and the environment seems to strike a chord. I want to look at HC Gilje’s work along this axis. His work gently reconfigures this relationship, deconstructing technology into basic, elemental forms only to re-weave it to intensify the world around us.

In Trace (2013), white light pulses glide through a dark, industrial basement. They seem to emerge from the walls and travel slowly across the room, lighting the space and spraying shadows across the floor; they twist and jump; the nondescript fittings lining the space — pipes and cables — throw off quick pockets of darkness. It’s hard not to think of these pulses as little signals, packets of data, which travel too as pulses of light and voltage through the networks all around us; but Gilje has slowed them down and carefully drawn them out into the room. And here they are signals again, but in a different way. The network’s optical pulses serve communication; their energy is literally channelled, sender to receiver, boosted and contained, passing the message on. We never see it: to see it would break the chain, and the message would be lost. The pulses in Trace are not messages: they are pings. A ping is a signal whose only purpose is to evoke a response; an impulse to create echoes. In this case, a light to create shadows, to push energy into the world in order to reveal it.

In a series of later works these energy pulses move through forests and tunnels, over lattices and frames. Their slowness is notable, and again unlike the data-pulses we usually inhabit. Information and communication technology sets out to collapse space through a process of accelerated transmission; lightspeed flickers that cross the ocean in tenths of a second, and faithfully reproduce what is here, over there. In the pulse works Gilje inverts this process; instead of collapsing space, he expands it, opens it up. This slowness is a form of scanning, a methodical sweep; instead of tunneling through space Gilje lingers on the details; the pivoting shadows are a sort of matrix of implications, a fleshing out that ramifies and multiplies naked spaces and minimal structures into holographic depth.

In Beacon (2016) the slow pulses return, though here reconfigured into orbital sweeps rather than linear scans. Once again light, space and information come into play. A beacon is a signal in primal form: a marker of presence that says only "I am here", its information content is spatial and relational, rather than encoded. The beacon can tell me where I am, but only in relation to the signal of its own presence. Again these signals scan the room, forming an interlocking matrix of light and shadow; they mark three bright points, but in the slow play of their beams this intensity branches out to fill the space: tiny reflections and revelations emerge all around. Instead of the two points of stable orientation — the sailor and the lighthouse — this space is here and here and here and here. As ever, Gilje uses light as a material rather than a neutral carrier; it acts in a spatial and material ecology. The watery lenses of Beacon mirror and invert the material terms of the lighthouse; instead of a point of light standing over the ocean, the ocean is internalised. In fact it becomes a technology, a lens to focus and direct light, but one that deliberately bypasses the refined technological ancestry of optical glass and mirrors. A proto-technology, a pre- or alter-technology, emerging from the interaction of simple materials.

The rotary sweeps of Beacon are prefigured in Barents (Mare Incognitum), where Gilje’s custom-made orbital camera scans the Barents sea in slow, stomach-turning cycles. At first glance this work seems to be at odds with the artist’s minimal, sculptural palette of light and space, but the same ideas are at work. Barents scans its environment just like Beacon and the light pulse works. What it gathers are (superficially) images, but the rotary movement of the camera literally twists them out of our grasp, away from the familiarity of landscape and towards an implacable machine vision, like data from a space probe or a satellite. There is no clear message in these scans, no identifiable subject, but a spinning field of flux — a forensic sample that carries with it a material force. In screening the work it sprays past the edges of the screen, into the surrounding environment. Despite an apparent blankness, its felt implications are unavoidable: a queasy, churning, pervasive anxiety. Not necessarily for the ocean, which spins on regardless, but for our stable human point of view, which seems to have been permanently unmoored.

In treating video as a material force Barents shows its connections with Gilje’s light projection works, such as the Blink series, which once again adapts technologies of mediation into architectures of intensification. In these works digital projections are precisely tailored to prepared environments; image becomes an articulated structure of light, painting and playing the space. As I have argued previously, this approach is aligned with a powerful post-screen trajectory in contemporary media arts. The most overt symptoms of our technologised environment are the "glowing rectangles" all around us — from the one in your pocket, to the one in your office, and the one in your living room. The screen is a hole in space — a universal window to elsewhere, anywhere, but never here. Gilje’s environments subvert the screen twice over. First they spatialise it, inflating the universal rectangle and adapting it to the room, addressing what is here, rather than importing what is elsewhere. Second, these works wind back the image to its material constituents: it becomes a concrete matrix of light, a bundle of energy beams. Once again these are pings, pulses bouncing through the room; in coming back they are returning space to us, and maybe bringing us back to space as well. Reflection and diffusion are key; incident light (ordinarily the projected image) triggers a chain reaction of echoes, sprays, echoes of sprays and sprays of echoes. Light and space are interleaved; projecting on wall and floor simultaneously generates a reciprocal volume, a crossing of image and reflection that opens into an integral landscape.

The ping is an impulse for response; shouting to hear an echo, or shining a torch in the dark. Energy beamed out to test what returns. What do Gilje’s pings return to us, then? Here again the artist works against the grain of information, for these impulses don’t bring us a simple answer. Gilje describes his practice as "conversations with spaces", and a conversation is always more than a question answered. What they return is an intensification of space, a heightened and performative presence. Networked media and technology encase us in holes, thread us together with faithful transmissions from elsewhere. As in Weiser’s vision of ubiquitous computing, technology forms a "human environment", but in many ways this comes at the cost of our presence, our sense of being in the world; and finally this is what Gilje’s work offers to return to us.