The marriage of art and science

Valencia isn't the first city to commission spectacular buildings to impress the world, but it does have the luck to be the home town of the visionary architect Santiago Calatrava. Jay Merrick visits Spain and is dazzled by the scale and beauty of his work

At 11.08pm, the television in room 407 of Valencia's Holiday Inn Express is showing FlashBack Regreso al Pasado. In front of a small, hip-looking studio audience, a portly man in a three-piece suit – think oleaginous pool-shark Minnesota Fats in The Hustler – is physically restraining a middle-aged woman called Maribel. She's on a red sofa next to her friend Manuela, who's also been put into a trance.

Maribel is hysterical, jerking around like a lipsticked Joe Cocker. The hypnotist has sent them back in time, to a painfully shared moment in their lives. The show's director keeps cutting to a close-up on the face of a pretty twenty-something who's stifling laughter.

Look out of the window of that room, over the medium-rise hectareage of the El Saler commercial centre, and another programme is on view half a kilometre away. It has a title – City of Arts and Sciences – and it stars a collection of buildings that, as midnight approaches, resemble luminous, arachnid motherships. Minnesota Fats and the mumbo-jumbo sisters are still at it but, in Valencia, Santiago Calatrava is the hottest show in town.

Calatrava's extraordinary architecture is problematic in one sense, because to experience it is to find one word turning over and over in the mind: beautiful. Understanding why it's beautiful is an interesting exercise, but not one that may seem important to the millions who have already flocked to the centrepiece Museum of Science and the glittering, half-submerged eyeball next to it known as L'Hemisferic.

And how many will also wonder if this fabulous architecture is only that – an arbitrarily beautiful landmark into which various forms of knowledge and interactivity can be crammed to suit seasonal programming? It's a question that applies to virtually all large new-wave visitor attractions – perhaps most particularly in our own Lotto-sculpted landscape. But the question is often downplayed in the names of throughput and urban regeneration.

In Valencia, despite the huge popular success of the museum and L'Hemisferic – and the locally proud fact that Madrid and Barcelona possess nothing so obviously stupendous – the problems facing the curators in the museum's sensational series of spaces cannot be airbrushed away. At the Museum of Science, the directors were given little opportunity to discuss, in advance, the detailed in-use requirements of the building with either the architect or Valencia's project managers. The directors were given a year to devise their schema, by which time the building was more or less done and dusted.

Calatrava designed the 41,000sq m science museum to transcend what the Valencian government describes as "the traditional notion of the museum as a storehouse for the custody of works of art. It encourages the present-day concept of culture as a live activity in touch with social tendencies and all kinds of audiences". Translation: in order to attract the widest possible audience, it must be modern in terms of its ability to entertain.

If interactivity – the "gee-whiz" factor – is the key, does the container matter that much? The short answer is that, even if it doesn't, you might as well have a great building in which to push buttons and activate stuff. Calatrava has delivered two so far in the City of Arts and Sciences. L'Hemisferic is sold as The Eye of Knowledge, a rather portentous tag considering that it operates simply as an Imax cinema, laserium and planetarium.

The Museum of Science's form draws from the female body and falling water. As usual with Calatrava, it is beautifully sculpted music for the eyes; and they really know how to form and finish concrete in Spain. Repetition, interlocking shapes, asymmetry, subtly melting tensions, moments of soaring release – it's all there in a strangely gothic take on monumental Modernism. The Museum of Science might almost be part of a post-millennial Brasilia remix. Oscar Niemeyer, Brasilia's architect, would have loved it.

But it is still portmanteau architecture, a generalist building in which curators find themselves dealing with beautiful – that word again! – spaces as best they can. The truth is that architects and interactivity do not yet mix coherently. And if the gizmo suppliers aren't quite sure what sort of spaces they need, why should architects worry excessively about the kind of internal volumes they supply? Perhaps the problem is insoluble in the short term; the history of large-scale interactivity-cum-education has, after all, only just begun.

Two of the science museum's sections provide good examples of the relationship between the overall space and the interactivity, and they happen to be supplied by British specialists. Helifilms' Space Academy is a progressive series of modules which simulate the experiences of weightlessness, rocket launch, docking with the International Space Station, re-entry and touchdown. It's remarkably effective: realistic G-force effects are created in the docking module, and the zero-gravity chamber is a particular triumph; nothing floats past you, but the sense of disorientating weightlessness is very cleverly achieved.

The Space Centre – whose 24-minute "ride" is educational and experiential rather than interactive – opened two weeks ago, and two-hour queues became the norm within days. The Space Centre's layout is surprisingly compact, a modest intrusion in the cathedral-like space of the Museum's soaring top-floor exhibition area.

The displays supplied by Ian Russell of Interactive Science Ltd are a charming throwback to the hands-on era of interactivity. Two of them, demonstrating the gravitation of black holes and planetary systems, are decidedly low-tech, yet addictive. Yet the Space Centre, Russell's series of apparatus, and much of the rest of the "experiences", are rather humbled by the gloriously moulded space above and around them.

The relationship between exhibits and internal volumes works a little better on the museum's first floor because the ceiling is quite low. Not dull, though. Calatrava's structural form has produced a flowing and interlocking overhead ferro-concrete grid of wonderful plasticity.

That sense of plasticity is everywhere: in the crafted beauty of the north façade, the accordioned waterfall glazing of the south façade, and in the steel tracery and Gaudiesque car-park vents of the L'Umbracale raised gardens alongside the Museum. The delicacy of those steel arches is quite wonderful, and the eye returns to them again and again because the scale – overall, and in detail – is so satisfying. If the museum building is a grand organ piece by Louis Vierne, L'Umbracle is a repeated tracery of harpsichord notes.

The City of Science is a tribute to Valencia's ambition. When the other buildings are completed – the opera house, take note, will be a 24-carat wonder – the city will not so much have been Tango'd, but Calatrava'd. There is, though, the lingering suspicion that the Museum of Science could just as easily have been morphed, without much change, into an equally dazzling airport terminal.

Not that Minnesota Fats would care. In room 407, we have touchdown and audience-lock. Fats is tapping Maribel and Manuela on their foreheads. The ladies wake up, startled. The studio audience applauds. The pretty girl is still doubled over with laughter. She loves a bit of interactive.

More of Calatrava's work can be found on his website, www.calatrava.com