geek learn science

Why is light the fastest thing ever?

Light travels at the speed of 300 000 kmph or about 180 000 mph, which is a LOT. In fact, any object with mass cannot travel at that speed as you’d need to spend a infinite amount of energy to accelerate a body to that speed.

The fact that light, when stationary, is without mass allows light to travel only and only at the speed of light. In fact, any object that has no rest mass will travel at the speed of light.

Now you know why light is the fastest thing ever.

geek learn science

Misconceptions about the Universe? Well, learn that it is expanding at more than the speed of light

The Universe is expanding at more than the speed of light. In the near vicinity of us, up to 1 megaparsec, the space is expanding with about 70km/s, but at 2 megaparsecs, at 140km/s and so on. After a certain distance, the space is expanding as a rate faster than the speed of light. The Universe has been expanding faster that the speed of light since the Big Bang or everywhere stretch.

Thanks, Veritasium, for reminding us that we won’t reach some of the galaxies ever-never-ever 😛 Now, we cannot move through space faster than the speed of light, but that won’t stop space from expanding at more than the speed of light. In a certain way some galaxies are travelling farther away from us at more the speed of light right now. Ooops.

The Hubble sphere is the area beyond which everything is moving away from us faster than the speed of light. Just learned something new 😀

geek science

What if you would throw a ball at the speed of light?

Randall Munroe, the creator of XKCD and What IF XKCD, explains what would happen if you were to throw a baseball with a speed near the speed of light. If you throw a ball at 90% the speed of light then the air molecules get hit so hard that thermonuclear reaction occur and a flood of X-rays will spread out in a bubble with plasma inside.

Then a fireball will engulf the entire stadium resulting, in a short time of 40 nanoseconds, in a big explosion with a mushroom cloud rising over a good part of the city where the stadium was.

He also replies to many “what if” questions from which we can better understand how the things work around us and why some ideas cannot be simply be put in practice. Follow his What Ifs here.

geek learn

We can travel in time, theoretically. Forwards, but maybe backwards too

Head Squeeze tells it in simple words: Einstein’s relativity theory tells us that, if we travel at 99.5% the speed of light, we will tavel forwards in time with about 10 minutes for every minute. Now that is something.

The time travel is possible due to time dilation predicted by the relativity theory of Einstein. If reference systems move at different speeds then the time flows different in each of these systems. In any case, Einsteins physics, coupled with quantum physics are really strange. It is said that using wormholes we can travel back in time.

In each of these cases, forwards in time or backwards in time, we would need an absurd amount of energy. Best is if we word on quantum computers instead, ok?

entertainment geek

Mind bending game: a slower speed of light from MIT Game Lab

MIT Game Lab has the purpose to create games that promote technology and science in a fun way. In A Slower Speed of Light they created a game where you have to collect sphere and, after you collect enough such spheres, you will see a different light around you because you will be moving close to the speed of light.

Things around the speed of light are slightly different and Einsteins Relativiy comes at play in this video game too. You will experience effects like Doppler effect, the searchlight effect, time dilation, Lorentz transformation, and the runtime effect.

Via [Rares Twitter Feed].

learn on the web

The speed of light in glass – it’s the same, trust me [mith]

Guess you already knew that. But many don’t know that the speed of light in transparent materials is the same, but strange things happen as we measure that it is, in fact,… slower. Now what’s that?

Well, it’s true and false. Yes, the speed of light is the same, when we see the light as wave and then as particle, but it takes more time to cross the transparent material (glass) because it bounces back and forth from the atoms in that material. Now you’re coming back.

Watch an inspiring educational movie by Minute Physics. So, let’s get Physics-cal at light speed.