Incredible Curiosities #4

1. My time is not your time

For many years, classical mechanics assumed that time was absolute to everybody, independently of their physical state (moving, standing still,...).However, Einstein came to prove these folks wrong. According to the principle of relativity, light is a constant velocity, c, and will always remain the same (in vacuum). Then, this would not follow the theorem of addition of velocities proposed by our friend Newton. This is how Relativity emerged. Through some calculations I will not cite now, it proved that, the bigger your velocity or the gravity you are experiencing, the slower time passes to you.

2.Spooky Action at a Distance

Have you ever felt that you were “magically connected” to someone? That actually exists, and it is called Quantum Entanglement, or “spooky action at a distance”, according to Einstein. Two particles are entangled when one action upon one particle immediately affects the other, that will do the exact opposite of its partner, despite any distance. Albert Einstein was firmly against this thought, and, unlike Schrodinger and his dead-alive cat, believed everything was already ‘prearranged”

3. Black Holes shrink over time

Nothing is eternal. Not planets, not stars, not even our universe. So, of course not black holes. Scientists thought that black holes would eventually die with our universe, when they run out of matter to “eat”. However, it looks like they might even be gone before that. The brilliant physicist Stephen Hawking discovered what he calls “Hawking Radiation”. It is based on the exchange of mass between a black hole and its outside, where, eventually, they would lose all of their mass.

But don’t get your telescope and expect to watch a black hole disappearing. It would take billions, billions of years for this to happen. Maybe, even longer than the age of our own universe -- one of the reasons why we never really observed that.

4. Light is a wave… I mean, a particle

Have you ever wondered what light is? Well, this is a very, very old question. Back in the ancient times, people believed that light emanated from our eyes until somebody came to prove this wrong. Now, you must think: “Of course scientists know what light is… We are so advanced!” Oh, sorry for that. What we do know is that, sometimes, light acts like a wave and, sometimes, like a particle. This is called the particle-wave duality. It was first discovered through the famous double slit experiment.

5. Nothing ever touches anything

This idea seems absurd. We all feel when we touch our skin, the grass or a blanket. How can that be untrue? But this is what really happens. At a quantum level ( this is, to the size of atoms), there is no “touching”. What we perceive as “touch” is simply the interaction among atoms. This can be a bit frustrating indeed, having such a logical and natural statement being (once more!) contested by scientific minds. Physically saying, the closest you can ever get to someone is when you are a baby in your mother’s uterus -- yes, physics can be beautiful.