Black Holes and Dark Matter explained [video]

Today I had some free time so I roamed through some YouTube videos and stopped at these. They explain what black holes are and why dark matter is such an important concept for astrophysicists.

Black holes are cosmic objects so dense that not even light can escape from them if it gets too close. They have usually millions of solar masses and can eat up entire stars. Dark matter on the other hand is a term used to define a huge amount of mass of the Universe that is not composed of black holes, stars, comets, asteroids or plantes.

It is believed to be composed of WIMP or axions, subatomic particles that do not interact with light. Also, today (13th April 2012) Science Daily reports that the dark matter it could be composed of Majorana particles, named after italian physicist Ettore Majorana. Ettore deducted that the Majorana particle is at the border of matter and antimatter and that it is in itself particle and anti-particle.

This is getting weird. But nothing form quantum physics ever was “normal” 😀 So, enjoy the videos and let’s be happy that even Sci-Fi movies missed the incredible findings or today.

The Dark Matter Mystery: Stars Are Moving Too Fast

The Dark Matter Mystery: 39 Billion Missing Suns

The Dark Matter Mystery: Gravitational Lensing

The Dark Matter Mystery: Most Of The Universe Is Missing

2 Responses to “Black Holes and Dark Matter explained [video]”

  1. “Black holes are cosmic objects so dense that not even light can escape from them if it gets too close.” Not true, as it takes forever to reach this dense object due to time dilation. Please do not mislead the public. See “Basic Assumptions and Black Holes”, Physics Essays 22, 559 (2009). You may read this paper at http://www.analysis-knowledge.com/msgTeaching.htm. In other words, the gravitational distortion of geometry is such that there is no inside to this denses object.

    • I mentioned “IF”, speaking of hypothetical situations. Even ESO seems to agree that “[…]a black hole’s event horizon, the boundary from within which not even light can escape.” http://www.eso.org/public/news/eso1229/

      Yes, thinking of Einsteins Special Relativity in which we know that time flows faster as you get farther from the center of gravity (see GPS and atomic clocks), yes, indeed, it would take infinity of time to get to the center of a black hole.

      IF you were to put light behind the event horizon that light would never escape, right? That was my reasoning. Thanks for the links. Astrophysics is interesting enough to devote long enough time to even learn those formulae 😀