Try talking to yourself without opening your mouth, by simply saying words internally. What if you could search the internet like that -- and get an answer back? In the first live public demo of his new technology, TED Fellow Arnav Kapur introduces AlterEgo: a wearable AI device with the potential to let you silently talk to and get information from a computer system, like a voice inside your head. Learn more about how the device works and the far-reaching implications of this new kind of human-computer interaction.