Need of High Energy Physics to Discover Particles

From the discovery of electron, proton and neutron, physicist believed that these are the fundamental particles from which matter is made of. But later on, with the with the growth in technology, scientists were able to detect many other unstable subatomic particles. It was very difficult to produce unstable particles, because of their very short life span.

Due to their ‘point like’ structure, these are called fundamental particles and these are very hard to detect, but quantum mechanics provided us a good way to detect and produce these smaller particles. The concept is straight forward, we just have to increase the energy of incident particles. Let us understand this process mathematically.

From de Broglie hypothesis, we know that the wavelength associated with moving particle is given by

$\begin{equation}\lambda=\frac{h}{p},\end{equation}$

where h is Planck’s constant and p is the momentum of the particle.

Now, if beam of the particles have energy corresponding to momentum p, then the resolution of the instrument which is measuring the particle of the beam must be comparable with this wavelength, i.e., if $\triangle r$, is the minimum resolution of the instrument then

$\begin{equation}\triangle r = \frac{h}{p}.\end{equation}$

Hence, we can say that, if we increase the energy to higher and higher value, we can easily detect smaller and smaller particles. With the technology advancement, we are able to produce high energy and able to detect smaller particles. In the beginning of twentieth century, technology was not so advance to produce high energy and therefore we were able to detect only few subatomic particles like proton and neutron.