Dark matter is a hypothetical type of matter. It does not emit with electromagnetic radiation. Light emit with electromagnetic radiation, so we can see light in electromagnetic spectrum. But we cannot see dark matter. It is invisible in electromagnetic spectrum.Read more
A photon have dual nature: Wave and Particle. A photon is described by wave vector in quantum field theory.
The energy and momentum of a photon depends only on its frequency or inversely, its wavelength
Why fire burns upward? Usually you see that fire burns upward but you ever thinks about why fire burn upward? Why fireRead more
Scientist calculates that, In the universe 73% dark energy, 23% dark matter and 4% normal matter. Now, you know that dark energy and dark matter both are very important because they have almost 96%. When scientist use the telescope for seeing in the universe, then they feel something which invisible (something dark) and then they called it ‘Dark Matter’.Read more