What is the main evidence for the Big Bang theory?

The main evidence that we currently have to support the Big Bang Theory is the cosmic background radiation. This is electromagnetic radiation that appears to be evenly spread throughout the universe. It is mostly in the microwave spectrum, equating to a temperature of about 3K. This suggests that the universe was once very hot and compressed, and as the universe has expanded, the once very high energy, short wavelength radiation has red-shifted to lower energy, longer wavelength microwave radiation.

SE

Related Physics A Level answers

All answers ▸

The vehicle accelerates horizontally from rest to 27.8 m s–1 in a time of 4.6 s. The mass of the vehicle is 360 kg and the rider has a mass of 82 kg. 1. Calculate the average acceleration during the 4.6 s time interval.


A water jet starts at a point X and reaches its maximum height at a point Y. Air resistance has a negligible effect on the motion of the water jet. (i) State the direction of the force acting on the jet at Y. (1 mark)


Describe how a stationary wave is formed at a boundary?


Explain why a transformer is used in electrical power lines.