How's my presentation?

[AviSchiffmann]

Hey guys I have 3 minutes max to make this presentation. How are the facts in this? It's about how black holes work. Also if anyone has any cool ideas on how I can visually do an experiment relating to black holes or anything in the video please tell me. Also should I get rid of the part about field equations and replace it with hawking radiation or the photon sphere? Thanks!

 

 

(Black solid with text saying 40 billion M☉)

40 billion solar masses.

(Cut to me)

That’s the size of the S5 0014+81, the largest known black hole in the universe. But did you ever wonder how they work?

 

It all begins with Stars. In their core, nuclear fusion combines four hydrogen nuclei into one helium nucleus, releasing an enormous amount of energy in the form of radiation. This energy pushes against the gravity on the star, maintaining a balance between forces. The energy from the fusion allows stars to fuse heavy elements until it reaches iron. Iron does not release any energy when it is fused, so gravity gains the upper hand, breaking the equilibrium. When a very massive star uses the rest of its nuclear fuel, and there are no more reactions to fight the gravity, it explodes as a supernova. If the core remaining is at least 2.5 times the mass of the sun, gravity will eventually collapse the core into a singularity. A singularity is a mathematical point with virtually zero volume and infinite density.

When this happens, it would require a velocity greater than the speed of light to escape the singularity’s gravity. According to Einstein's Theory of Relativity, it is impossible for any object to reach a speed faster than light. Therefore any matter or radiation, including light, that passes within the event horizon of a black hole is trapped forever.

Wait. What was that about the Einstein? (Maybe wear a cutout photo of Einstein as a mask? Or have Einstein as a green screen standing next to me)

In the early 20th century, Albert Einstein published two theories of relativity. The Special Theory of Relativity, and the General Theory of Relativity. But we only care about the general one right now. According to the general theory of relativity, matter and energy bend space and time. Also known as gravity. This is why objects that travel near a large mass will appear to move along a curved path in space-time. Why do we care? To do this theory, Einstein needed a set of formulas called the field equations. This is where Karl Schwarzschild comes in with a solution. The field equations state that an extremely dense ball of matter create a spherical region in space where nothing can escape. Sound familiar? That’s because it is. Using the field equations we know that if we have the mass of a black hole, we can determine the size of the sphere that surrounds the black hole. This is where Karl comes in. The radius of that sphere is called the Schwarzschild radius, and the surface area that surrounds that sphere is called the event horizon. And as we know from earlier, once something enters the black hole, it’s not coming back.

Is there only one type of black hole? Nope! There are three main types that are classified based on their size and mass. The smallest ones are known as Primordial black holes, and are believed to be as small as an atom, but have have the mass of a mountain. Next there are medium-sized black holes. These are called Stellar black holes because their mass can be up to 20 times greater than the mass of our sun and fit into a radius of 8 km. Then we have the champion of all black holes. Supermassive black holes have masses that are greater than 1 million suns and are about as big as our own solar system. Scientists believe that a supermassive black hole resides in the center of all galaxies, including the milky way.

Edited June 10, 2018 by AviSchiffmann

[Mordred]

Not bad fairly accurate. I would keep the mention of the field equations and Schwartzchild. Hawking radiation and the photon sphere are other dynamic involved with a BH they don't define a BH.

Edited June 10, 2018 by Mordred

[koti]

Looks nice and compact. As for the visual experiment I would try to show the scales to „wow” the attendants.