Why is it not possible to look all the way back to the Big Bang itself?
A)Photons are not produced until the stars begin to shine at a redshift of z ≈ 20.
B)From redshifts of z = 0 to 100,photons are gravitationally lensed by the dark matter in the universe.
C)At redshifts of z 1,000,most of the photons are blocked by large amounts of cold gas and dust.
D)For redshifts of z 1,000,photons are heavily altered because they easily react with individual protons and electrons in the universe.
E)Photons from the Big Bang would be so strongly redshifted that we could never detect them.

Question

Why is it not possible to look all the way back to the Big Bang itself?
A)Photons are not produced until the stars begin to shine at a redshift of z ≈ 20.
B)From redshifts of z = 0 to 100,photons are gravitationally lensed by the dark matter in the universe.
C)At redshifts of z > 1,000,most of the photons are blocked by large amounts of cold gas and dust.
D)For redshifts of z > 1,000,photons are heavily altered because they easily react with individual protons and electrons in the universe.
E)Photons from the Big Bang would be so strongly redshifted that we could never detect them.

Quizplus · Accepted Answer

Before the universe became transparent, it was a hot, dense plasma where photons were constantly interacting with protons and electrons, preventing them from traveling freely. This state persisted until the universe cooled enough for electrons and protons to combine into neutral atoms, a period known as recombination, which occurred at a redshift of z ≈ 1,000.

Why Is It Not Possible to Look All the Way