# The Biggest Questions in the Universe

- Institution: Gresham College
- Speaker: Professor Joseph Silk
- Year: 2015
- Level: For everyone
- Language: English
- Subjects: Physics, Astronomy and space
- Source: [Gresham College](https://www.gresham.ac.uk/watch-now/series/biggest-questions-universe)
- Licence: [Educational use (Gresham College's terms)](https://www.gresham.ac.uk/terms-and-conditions)
- Who can watch: Tweens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

The universe underwent an inflationary period of expansion. From an extremely hot beginning, it cooled down then reheated to form the expanding universe that we observe today. The relic radiation generated the fossil glow of the cosmic microwave background radiation, a testament to its fiery origin. Microwave telescopes map out the structure of the universe long before the galaxies were present, only 370,000 years after Big Bang. The current challenges in cosmic microwave background astronomy will be described.

## Lectures

1. [The Primordial Fireball](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/33ca8f064209) (YouTube)
2. [The First Stars](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/583be8c73283) (YouTube)
3. [Galactic Archaeology](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/85d8bff94f12) (YouTube)
4. [The Formation of our Galaxy](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/69e1f5f16eb8) (YouTube)
5. [How Common is Life in the Universe?](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/fc0c409d611d) (YouTube)
6. [The Dark Side of the Universe](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/8d1ec8cc6062) (YouTube)
7. [Black Holes](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/82f3e15038af) (YouTube)
8. [The Expanding Universe](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/9aa7e6d39772) (YouTube)
9. [The First Three Minutes of Creation](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/edf7d60dd18f) (YouTube)
10. [Should We Trust a Theory?](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/5116faf17bce) (YouTube)
11. [The Accelerating Universe](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/c370ae9070c4) (YouTube)
12. [Observing the Dark Ages](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/2798d01b32ee) (YouTube)
13. [How Were The Stars Formed?](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/26babee3e6da) (YouTube)
14. [Are We Alone In The Universe?](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/83f07a1e3aa9) (YouTube)
15. [How Special Is Our Universe?](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/e3bbeee570c4) (YouTube)
16. [The High Energy Universe](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/e37c868102b9) (YouTube)
17. [Elementary Particles and Their Interactions](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/ac0d16497230) (YouTube)
18. [Existential Risks in the Solar System](https://invisiblenetwork.ai/learn/gresham/series-biggest-questions-universe/a745c5c2956c) (YouTube)