Wormholes and Blackholes

Blackholes are a region of spacetime with a gravitational effect so strong that nothing can escape it.

Looks completely black because it absorbs any light it touches.

What are black holes?

No force can keep a dead star from collapsing under the influence of gravity.

However, instead of collapsing forever on a single point, as the star collapses, it gets closer to its event horizon.

Time on the “Surface” of the star slows down relative to observers. When the surface reaches the event horizon, time stops.

How do black holes form?

Most black holes form from the remnants of a large star that dies in a supernova explosion.

Small stars (less than 8 solar masses) turn into white dwarves.

Larger stars (8 to 30 solar masses) turn into Neutron Stars.

Stars of more than 30 solar masses turn into black holes.

Structure of a black hole

Stellar Black Holes

• Formed from the deaths of individual stars.

• Small compared to other black holes, but very dense.

• Consume surrounding dust, gas, and when they get big enough, other celestial bodies, in order to grow bigger.

Intermediate Mass Black Holes

• Mass is too high to have formed due to the collapse of a single star.

• There are three theories as to how these could have formed:

• - Merging of multiple high-density celestial bodies.

• - Runaway collision of stars in dense stellar clusters.

• - They are primordial black holes formed just after the Big Bang.

Theory 1: Merging

Mass was reached via the merging of multiple high-density celestial objects, sun as black holes and neutron stars.

This explains why they have so much more mass than stellar black holes.

Theory 2: Stellar Chain Reaction

Mass was reached via the collision of several stars.

Theory 3: Primordial Black Holes

Formed right after the Big Bang, when most of the universe was compacted into a few cubic centimetres, making it easy for black holes to form.

Due to the high density of matter, it would be easy for black holes with a mass much higher than stellar black holes to form.

Supermassive Black Holes

Black holes with a mass higher than 100,000 solar masses.

Exist at the centre of every large galaxy.

No exact cause for the formation of these objects has been determined

When these black holes feed, they are referred to as quasars and essentially become galaxy-sized stars.

Wormholes:

A wormhole is a tunnel that connects two black holes or 2 points in space-time.

It can act as a shortcut to reduce travelling times.

Reflection:

Today’s lesson was interesting and I learnt a lot about black holes, wormholes and white holes. The presenters kept us engaged and we were having fun understanding the different concepts of wormholes, black holes and white holes. The presentation was not rushed. To summarise, we learnt about different black holes and the physics behind them. We also learnt about the different white holes and the physics behind them. We also learnt about how wormholes work.