Indians are certain they invented the zero. But can they prove it? NEW DELHI — Indian students are taught very early in school that India’s contribution to the world of mathematics is zero. Way back in the 5th century, an Indian mathematician used zero in the decimal-based place-value system, an achievement that citizens here have always celebrated with pride. Now, a small but ambitious team of Indian and international scholars called Project Zero wants to go deeper. In the past year, they have been asking the question: What made the invention of zero possible in India? The initiative is a heady cocktail of academic research and cultural pride, and it coincides with a new wave of hyper-patriotism among Indians that has risen since Hindu nationalist Prime Minister Narendra Modi came to power in 2014. Indians are reclaiming their heritage, embracing yoga , promoting the ancient Sanskrit language, buying traditional herbal products and celebrating — at times exaggerating — ac