Big Bang Theory

2. A pair of equal and oppositely charged or magnetized poles separated by a distance.
4. The study of the relations between heat, work, temperature, and energy.
7. A star that pulsates radially, varying in both diameter and temperature.
10. Unit of thermodynamic temperature.
11. when an object is moving towards us, the light from the object is known as __________.
13. The strong force, the weak force, the electromagnetic force, and the gravitational force.
15. Hypothetical form of matter.
16. The science of the origin and development of the universe.

1. Physics is the only science that specifically studies it.
3. A theory - introduced in 1981 to solve several important problems in cosmology.
5. Apparent change in frequency of a wave in relation to an observer moving relative to the wave source.
6. An alternative term for the radiation era in the Big Bang theory, during which the Universe was hot and dense and was dominated by the effects of radiation.
7. Average density of matter required for the Universe to just halt its expansion, but only after an infinite time.
8. A completely empty space.
9. The physical interaction among electric charges, magnetic moments, and the electromagnetic field.
12. A system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity.
14. A point at which a function takes an infinite value, especially in space-time when matter is infinitely dense, as at the center of a black hole.