Flashcard: 1.2: The Big Bang Theory [Notes]

Front

What is the Big Bang Theory?

Back

The Big Bang Theory is the leading explanation for the origin of the universe, proposing that it began as a singularity approximately 13.8 billion years ago and has been expanding ever since.

Front

What is cosmic background radiation?

Back

Cosmic background radiation is the afterglow radiation from the Big Bang, filling the universe and providing evidence for the Big Bang Theory.

Front

What does redshift indicate about a galaxy's movement?

Back

Redshift indicates that a galaxy is moving away from Earth, as the light waves are stretched to longer wavelengths.

Front

What does blueshift indicate about a galaxy's movement?

Back

Blueshift indicates that a galaxy is moving closer to Earth, as the light waves are compressed to shorter wavelengths.

Front

Who is Edwin Hubble?

Back

Edwin Hubble was an American astronomer who provided key evidence for the Big Bang Theory through his observations of galaxies and their redshifts.

Front

What is the significance of Hubble's Law?

Back

Hubble's Law states that the farther away a galaxy is, the faster it is moving away from us, supporting the idea of an expanding universe.

Front

What is the observable universe?

Back

The observable universe is the portion of the universe that we can see and measure, limited by the speed of light and the age of the universe.

Front

What is the role of dark matter in the universe?

Back

Dark matter is a form of matter that does not emit light or energy, making it invisible, but it exerts gravitational effects on visible matter.

Front

What is the role of dark energy in the universe?

Back

Dark energy is a mysterious force that is driving the accelerated expansion of the universe.

Front

What evidence supports the Big Bang Theory?

Back

Evidence includes cosmic background radiation, the abundance of light elements, and the redshift of distant galaxies.