What If Earth Had 16.4 Billion People?

What if Earth's population doubled overnight? Imagine waking up one day to find out more than 16.4 billion people inhabit our planet. The world would be so packed that finding empty space would be nearly impossible. Densely populated cities like Tokyo, New York, São Paulo, and Cairo would quickly become impossible to live in. But this surge in people wouldn't be spread evenly. Asia's population would jump past 9 billion, Africa's past 3 billion. Europe's major cities would overflow, and North America would have tens of millions more competing for the same space. Nature wouldn't stand a chance either. Forests would be cleared for farmland, wetlands paved over for housing, and rivers drained faster than they could refill. With twice as many people fighting for the same resources, the world would turn on itself. Food and water would run out, power grids would fail, and countries would clash over land and energy, sparking wars that could engulf the planet.