5 desirable technologies the world will never see

4. Invisibility cloak

We were all Harry Potter fans. Remember how he wrapped himself in the invisibility cloak in the Philosopher’s Stone? Recent research has shown that there is a fundamental limit to how well cloaking devices can work without breaking the laws of physics. In nature, there are no materials capable of equally well reflecting waves of different lengths: light, radio waves. Hypothetically, even the best invisibility cloaks will only be able to make objects partially invisible.