evidence: India's richest man brings Rihanna, Mark Zuckerberg and 1,200 guests to a pre-wedding celebration for his son [...] Billionaire Mukesh Ambani is kickstarting big fat Indian wedding celebrations for his son, Anant Ambani, 28, who is set to marry his longtime girlfriend Radhika Merchant. [...] Indian billionaires Gautam Adani and Kumar Mangalam Birla are also expected to attend, along with retired cricketer Sachin Tendulkar.