As artificial intelligence grows bigger and more powerful, one problem is becoming impossible to ignore that is energy. Training and running advanced AI models requires massive amounts of data to move constantly between chips, servers and data centres. Today, most of that data travels through electrical signals and copper connections. But as AI systems scale up, experts say this approach could soon become a major bottleneck. That is why chip giant Nvidia is pouring billions of dollars into a technology many believe could redefine the future of AI infrastructure: photonics.