What Causes Cosmological Redshift of Photons That Reach Us from Distant

question 117

Multiple Choice

What causes cosmological redshift of photons that reach us from distant galaxies?

• A) The photons have moved from high gravitational field regions toward lower fields,thereby becoming reddened.
• B) The photons were emitted from the galaxies much earlier in time when the overall temperature of matter was much lower.Hence,the observed photons are redder,the farther away from Earth that they were produced.
• C) The photons have traveled across space that has been expanding and their wavelengths have expanded with it,becoming redder.
• D) The photons were emitted by objects that were moving rapidly away from us,and thereby have been reddened by the Doppler effect.

---

Definitions:

Cash Received

The total amount of cash received by a company during a specific period of time, from various sources.

Present Value

The current worth of a future sum of money or stream of cash flows given a specified rate of return, often used in investment and financial decision-making.

Compound Interest

Interest accumulation on a loan or deposit which is based on the principal amount as well as on all previously gathered interest from past periods.

Annuity

An investment vehicle designed to provide a consistent payment flow to a person, often employed to secure a steady income for individuals in retirement.