Definition

1. Noun:
   • Cosmic Background Radiation: In cosmology, cbr refers to the cooled remnant of the hot big bang that fills the entire universe. It is electromagnetic radiation that can be observed today with an average temperature of about 2.725 kelvin. It is a key piece of evidence for the Big Bang theory.

Usage Examples

• Noun:
  • The discovery of the cbr provided strong evidence for the Big Bang model of the universe.
  • Scientists study the minute fluctuations in the cbr to understand the early structure of the cosmos.
  • The cbr is sometimes called the "afterglow" of the Big Bang.

Advanced Usage

• "cbr anisotropy": Refers to the tiny variations in temperature of the cosmic background radiation across the sky. These anisotropies are crucial for understanding the distribution of matter in the early universe.
  • The Planck satellite mapped the cbr anisotropy with unprecedented detail.

Variants and Related Words

• CMB (Cosmic Microwave Background): This is the full, more common term for . is often used as an abbreviation for CMB.
  • The CMB is a cornerstone of modern cosmology.
• Cosmic Microwave Background Radiation: The complete, formal name.
• 3K radiation: An older informal name, referencing its approximate temperature of 3 kelvin.

Synonyms

• Relic radiation: Emphasizes its origin as a remnant from the early universe.
• Primordial background radiation: Highlights its ancient, original nature.

Noun

1. (cosmology) the cooled remnant of the hot big bang that fills the entire universe and can be observed today with an average temperature of about 2.725 kelvin