taustalähteestä

Taustalähde refers to background radiation in physics. It is the electromagnetic radiation that permeates all of space. This radiation is a remnant of the early universe, specifically from the Big Bang. The most prominent component of this background radiation is the Cosmic Microwave Background (CMB), which was discovered in 1964 by Arno Penzias and Robert Wilson. The CMB is a nearly uniform glow of microwaves coming from all directions in the sky, with a temperature of about 2.7 Kelvin.

The existence and properties of the CMB are strong evidence for the Big Bang theory. Variations in the temperature of the CMB, though very small, provide crucial information about the initial conditions of the universe and the seeds of cosmic structure formation. Scientists study these anisotropies to understand the age, composition, and evolution of the universe. Other forms of background radiation can also exist, depending on the context, such as general environmental electromagnetic noise or sources of light and sound that are not the primary subject of observation but may influence measurements. However, in a cosmological context, taustalähde almost always refers to the CMB.