The sculpture, called How It Is, is by Miroslaw Balka and is the tenth work in Tate Modern's annual series of Unilever commissions, which began with Louise Bourgeois' giant spider in 2000 and has since included an enormous sun, thousands of boxes and a giant crack in the floor.
The Warsaw-born artist has created a piece that the gallery fully expects will unnerve and unsettle visitors. The structure is enormous – 30 metres long, 10m wide and 13m high – and once inside it, visitors will walk into complete blackness hoping – presumably – that they don't then bump or knock into fellow art-lovers.
Tate Modern said health and safety had been on its mind and the space will be regularly patrolled by attendants with torches.
Balka is alluding to many things in the work – the biblical Plague of Darkness, black holes in space, images of hell – but curator Helen Sainsbury said reactions to the work would differ.
"Each one of us will approach this work and experience it very differently," she said. "For some it may be an incredibly sombre experience, for most it will be unnerving. For others there will be something quite comforting about going into a space like this full of strangers, yet being aware of each other."
Balka has been working on the piece, from concept to installation, for a year. Asked what his first reaction on walking into the completed container was, he said: "Whoa. It works."
The title, How It Is, is taken from Samuel Beckett's novel of the same name and Balka said the piece should be seen as being about everything and nothing. "There is no one single direct inspiration for the piece and the words of the artist are not so important. The work is important. It is good or bad. It works or it does not work."
Balka said he was using it as a space for contemplation and hoped others would do the same, just as people repeatedly visited Olafur Eliasson's The Weather Project in 2003, often lying on their backs and gazing up to the sun.
Tate Modern's director, Vicente Todolí, said it was a coincidence that this and recent commissions had been rather dark or sombre – before Balka there was Dominique Gonzalez-Foerster's shelter from permanent rain and Doris Salcedo's 167-metre-long crack in the floor. "When we select the artists we don't select them because of the possible message. We select them because of their past work and how they might deal with the space."
The work has been built by a structural metalwork company, Littlehampton Welding, and the interior walls are lined with a soft flock that is 10 times blacker than normal black paint. It can be seen free of charge from tomorrow until 5 April.
