For 10 points, name this effect used as evidence the universe is expanding and to calculate the distance of distant galaxies, an apparent lengthening of the wavelength of light from its source to its observation.
The Pound-Rebka-Snider experiment confirmed the Einstein or gravitational version of this effect, which also occurs when two beamed energy sources interact, an interaction known as the Wolf Effect. The Relativistic Doppler effect provides an exact equation for calculating this, an approximate form of which is z = v divided by c, where v is the velocity of the source of light that is moving away from the viewer. For 10 points, name this effect used as evidence the universe is expanding and to calculate the distance of distant galaxies, an apparent lengthening of the wavelength of light from its source to its observation.
The Pound-Rebka-Snider experiment confirmed the Einstein or gravitational version of this effect, which also occurs when two beamed energy sources interact, an interaction known as the Wolf Effect.
{redshift} (prompt on “Doppler” before it is read)