lesson 1.1

Question 1

● cosmological model explaining how the universe began.

Answer 1

big bang theory

Question 2

It suggests that the universe started its expansion about _____ ago based
on the latest calculations.

Answer 2

13.8 billion years

Question 3

● The idea of the big bang theory -> similar to the ____

Answer 3

bread-raisin model

Question 4

● The bread is compared with the ____, whereas the raisins are the _____.

Answer 4

universe, galaxies

Question 5

● The big bang theory suggests that the universe began as a

Answer 5

“singularity.”

Question 5

a point in the universe that is predicted to be in the core of a black hole with extremely high temperature and density.

Answer 5

Singularity

Question 6

The nature of the singularity is still a _____ but this singularity
expands and cools constantly.

Answer 6

mystery to many scientists,

Question 7

● The rate of expansion is __ to the rate of cooling.

Answer 7

almost equal

Question 8

what led to the formation of matter and antimatter particles?

Answer 8

The intense heat led to the formation of matter and antimatter particles that were
destroyed every time they collided with each other.

Question 9

is the formation of elements, such as hydrogen and helium.

Answer 9

Nucleosynthesis

Question 10

● The presence of these elements led to the formation of _____.

Answer 10

stars and galaxies.

Question 11

Proponents of Big Bang Theory

Answer 11

1. Georges Henri Joseph Edouard Lemaître
2. Edwin Powell Hubble
3. Arno Penzias and Robert Wilson

Question 12

● suggested the idea of the expanding universe.

Answer 12

1. Georges Henri Joseph Edouard Lemaître

Question 13

● first proponent of the big bang theory.

Answer 13

1. Georges Henri Joseph Edouard Lemaître

Question 14

universe originated in an explosive act of a primeval atom or the “cosmic
egg,” which was like a huge atomic nucleus

Answer 14

1. Georges Henri Joseph Edouard Lemaître

Question 15

● not supported by empirical evidence at that time.

Answer 15

1. Georges Henri Joseph Edouard Lemaître

Question 16

● the universe came from a hot state, it would leave traces that can be subjected to analysis. He then realized that there were traces in the form of cosmic rays

Answer 16

1. Georges Henri Joseph Edouard Lemaître

Question 17

● the universe came from a hot state, it would leave traces that can be subjected to analysis. He then realized that there were traces in the form of ____

Answer 17

cosmic rays

Question 18

were “ashes and smoke of bright but very rapid fireworks,”

Answer 18

cosmic rays

Question 19

primeval atom or

Answer 19

the “cosmic
egg,”

Question 20

● was an American astronomer who established Hubble’s law, which provided evidence that the universe was not static but expanding.

Answer 20

2. Edwin Powell Hubble

Question 21

● In ____, Hubble spotted what he thought was a flaring nova star in the M31 nebula or the Andromeda constellation using a Hooker telescope.

Answer 21

1923

Question 22

● The ______ is now known as the Andromeda galaxy, the nearest galaxy in the Milky Way.

Answer 22

Andromeda constellation

Question 23

Then in ___, he noticed that all the galaxies seemed to be moving away from Earth with velocities that increased in proportion to their distance.

Answer 23

1929

Question 24

This relationship of the velocities of distant objects in the universe in proportion to their distance from Earth is called

Answer 24

Hubble’s law

Question 25

● He published a report in the same year about his discovery.

Answer 25

2. Edwin Powell Hubble

Question 26

● In 1923, Hubble spotted what he thought was a flaring nova star in the ______ using a _____ telescope.

Answer 26

M31 nebula or the Andromeda constellation Hooker

Question 27

American astronomers Arno Penzias and Robert Wilson studied ____ in __.

Answer 27

cosmic radiation in 1964.

Question 28

● They discovered that microwaves with wavelengths of about ____.

Answer 28

7 centimeters were present in space.

Question 29

● They discovered that microwaves with wavelengths of about 7 centimeters were present in space.

Answer 29

3. Arno Penzias and Robert Wilson

Question 30

These waves were referred to as ______.

Answer 30

cosmic microwave background (CMB) radiation.

Question 31

is believed to be the thermal energy released when the ionized gasses became neutral particles as the early universe cooled down.

Answer 31

CMB radiation

Question 32

● This radiation served as a “___” when the universe was formed. The

Answer 32

leftover

Question 33

The discovery of this _____ provided strong evidence that the universe began from the sudden expansion of a singularity, which supported _____.

Answer 33

cosmic radiation Lemaître’s study.

Question 34

Drawbacks of the Big Bang Theory

Answer 34

1. It fails to explain how the universe was created 2. The big bang theory violates the assumptions of the first law of thermodynamic