London has a population of 7.6 million, and, with 2.3 residents added every hour, will have a projected 600,000 new citizens within the decade. This population will provide 20% of the United Kingdom’s GDP. Yet we are divided along ethnic and economic lines, and the demands of a boomtown capital makes our future seem uncertain.

These are the issues discussed in the Debate London talks and the Global Cities exhibition at Tate Modern.

Debate London included five debates over the last weekend. They discussed the future of a city alive with excitement and fear. Friday 22nd’s debate, 'Is London A United City?', was chaired with humour and insight by Hardeep Singh Kohli, presenter of Newsnight Review and writer of BAFTA-winning documentary ‘In Search of the Tartan Turban’.

The panel crossed the political and financial spectrum, including Boris Johnson; self-made billionaire Ivan Massow; Corporate Director of Tower Hamlets Emma Peters; left wing advocates and journalists Neal Lawson and Lynsey Hanley; and economist and governmental expert Tony Travers. The panellists outlined what they believed to be the causes of social divisions and suggested possible preventions.

Johnson, calling London "arguably the first world city since Rome", described Londoners as friendly and yet disunited, suspicious of strangers, with increasingly less solidarity and civility caused by "envy, self-loathing and rage". Johnson blamed this largely on the super rich, arguing that they should be integrated into society and encouraged to donate money.

Neal Lawson called for stiffer measures, including increasing the 10% taxes of the super rich to the average 40%. He further demanded the intervention of politics to stop harrowing statistical truths, such as the life expectancy that falls by a year with each stop travelled East on the Tube from Notting Hill.

The debate presented diverse solutions to the economic divide, ranging from taxes, greater social justice, and increased cohesion beginning in schools and ensured by affordable housing.

With challenging responses from the audience and heated argument from the panellists, including a loud ‘Tory bulls**t!’ from one panellist during a tax discussion, the debate was lively and relevant.

The exhibition

‘Global Cities’ presents the effects of urban growth on diversity, particularly through comparison with Tokyo, Mexico City, Sao Paulo, Shanghai, Cairo, Istanbul, Mumbai, Johannesburg and Los Angeles (LA).

27.1% of our population was born abroad, second only to LA’s 36.2%. Using this statistic the exhibition demythologises much of the stigma attached to immigration. Through digital footage and photography showing airline routes, worldwide houses, crowds and immigration patterns, London’s multiculturalism is given a map of origins, and a clear illustration of the economic counterbalance provided by immigrants for British born families leaving the city.

The exhibition also presents the effect of urban growth upon density of population. Our increasing populace will be contained within the 1943 Green Belt border of urban development, which currently covers 1,573 km2. By keeping the population within this boundary we are creating rapid inner city development. While digital images present the possible skylines of London following this spree of architecture in glittering new Gherkins, the other reality of development is presented in aerial photography and video footage.

High housing costs in relation to income will ensure that half the children in some central areas of London will contine to live below the poverty line. Conversely, the display employs thoughtful photography and sculpture to remind its viewers that our population is one million lower than its historical peak of 1939, and that our population density has the smallest growth rate amongst the ten cities.

The ten cities chosen explore the variety of worldwide architecture. This includes Oscar Niemeyer’s Sao Paulo modernist building photographed superbly by Andreas Gurskey, Mexico City’s identical houses and Johannesburg’s slums. Then there are Tokyo’s tightly packed homes, shown in Naoya Hatekayama’s 1/1000 scale paper model of the city.

Alongside these our own architects discuss the future of London’s cityscape. This is done with particular success by Nigel Coates in his scale model that, using biscuits, batteries, and golf balls amongst other items, presents the diverse cultures and lifestyle choices that will define the Thames Gateway following 160,000 new homes.

‘Global Cites’ is an impressive artistic social commentary, relevant for our times and a laudable attempt by the Tate Modern to inform its viewers of our social makeup and enliven public debate. It will remain open until 27th August 2007.