A Brief History of Time

5. The idea that the Universe is identical whichever direction we look in
7. the redshift or blueshift of the light expelled of an object moving towards or away from us
8. made the theory that the universe can expand, also made models to show it
11. The principle that uses the fact that we can make observations as a base to describe things cosmologically
13. boundary of a black hole
14. branch of physics that describes the smallest particles and how they work, contradicts the Theory of Relativity
18. regions where gravity is so strong that nothing can escape it
20. the electromagnetic and weak nuclear force acting as one at high temperatures
21. number of flavors of quarks
23. subatomic particles that make up hadrons (protons and neutrons)
24. the force that charged molecules exert
26. theory attempting to explain the combined forces
27. force responsible for radioactivity
29. one of the first people to think the Earth is round
30. the point where something takes an infinite value

1. E=mc^2
2. Found that not everything has to orbit the Earth, also found 4 of Jupiter’s moons
3. ________ duality is the property of expressing properties of both waves and particles
4. the principle that we can’t know both the speed and location of an object with complete accuracy
6. Albert Einstein’s theory that combined the ideas of gravity, space, and time
9. Geocentric model of the Solar System
10. the force that holds neutrons, protons, and atomic nuclei together
12. Discovered that stars could collapse under their own gravity to reach extremely high densities
15. narrator of the book, also did groundbreaking work with black holes
16. shows us what a particle looks like from different directions
17. The idea that the Universe is identical where ever we are
19. Laws of Motion
22. the force that two bodies put on each other as a product of their masses
25. generally accepted theory of the beginning of the universe
28. the measure of disorder in a system