India, Nov. 17 -- There was a time when Delhi's winter sun signalled a change in the rhythm of the city. The elderly would be the first to don their woollen and their caps as they went about their morning walks - their group of friends growing in direct correlation with the sun's trajectory in the sky. Some would be seated on park benches, others in their courtyards or even by the wayside, lost in animated discussions over steaming cups of tea. It was a ritual of community - of warmth, movement, and laughter.

Over the past few years, that familiar scene has practically vanished in the smog. For the elderly, the shared commons - the parks, the pavements, the markets - are now places to avoid. Once free and open spaces now feel unsafe, eve...