## Main Difference – Higgs Boson vs String Theory

Higgs boson is a fundamental particle of the standard model. But string theory is a theoretical platform which goes beyond the standard model. Higgs boson is no longer a hypothetical particle because the existence of the Higgs has been already confirmed. But string theory is not a completely developed theory. It is still being developed. **Higgs boson is the particle which gives other particles mass**. **String theory is not a solution for a single question, but it is an attempt at explaining all the fundamental interactions and also the way in which matter is made of**. This is the main difference between Higgs Boson and String theory.

This article explains,

1. What is Higgs Boson – Definition, Theory/Concepts

2. What is String Theory – Definition, Theory/Concepts

3. What is the difference between Higgs Boson and String Theory

## What is Higgs Boson

In physics, all the force carriers are bosons and therefore, they obey the Bose- Einstein statistics. Unlike Fermions, bosons have integer spins. There are several types of bosons, namely composite bosons, W^{+}, W^{–}, Z^{0}, gluons, photon, graviton and the Higgs. According to the standard model, photon and gluons are considered to be the mediating particles in electromagnetics and strong interactions respectively. Also, W^{+}– and Z bosons are the mediating particles in the weak interaction. In addition, the graviton is considered to be the force carrier in gravitational interaction.

The Higgs boson, also known as the **God particle**, is a boson with zero spin. It was named after a British physicist; Peter Higgs. Higgs is a fundamental particle with no electric charge or color charge. It is normally denoted by the symbol “H ^{0}”. Even though the Higgs is a mediating particle, it is not a force-carrier of fundamental interaction.

According to the concepts of particle physics, the mediating particles or force carriers mediate interactions with their respective fields. For instance, the photon mediates interactions with the electromagnetic field, and it is a quantum excitation of the electromagnetic field. Similarly, the Higgs boson mediates with the Higgs field, and it is a quantum excitation of the Higgs field. According to the standard model, the Higgs boson interacts with the Higgs field and gives all other fundamental particles mass. Therefore, this mechanism is considered to be one of the most important phenomena in science.

Unlike in photon, invariant masses of graviton or gluon are zero; the Higgs boson is a massive particle with a mass in the range of 125 GeV/c^{2 }-126 GeV/c^{2}. Therefore, a large amount of energy is needed to create a Higgs boson. In a particle accelerator, charged particles are accelerated and strike against each other. As a result, the energy of the particles is converted into mass according to the Einstein equation E = mc^{2} . In order to create a Higgs boson, a particle accelerator must be able to accelerate the particles very close to the speed of light because Higgs boson is a massive particle. However, in 2013, the Large Hadron Collider (LHC) at CERN announced that they had succeeded in discovering the Higgs particle. Even though the standard model isn’t a completely acceptable story of matter and energy, the existence of the Higgs particle confirmed some other important predictions of the standard model: the existence of the Higgs field, the Higgs mechanism, and the way particles acquire their mass.

Higgs is a very unstable particle. It has been observed that the Higgs particles decay into two Z bosons, two W bosons or two photons immediately once they are created.

According to the standard model, the Higgs particle was a hypothetical boson until it was discovered in 2013, which gives mass to all fundamental particles. Therefore, the discovery of the Higgs particle (2012- 2013) solved the deepest puzzle of the standard model. The Higgs is no longer a hypothetical particle but a reality. The discovery of the Higgs boson is considered as a milestone in fundamental particle physics and also as a landmark of the human history.

## What is String Theory

By 1950, the two radical theories; Einstein theory of relativity and Quantum physics seemed to be sufficient to explain most of the observed physical phenomena/ features in the universe. The two theories were used to explain the things from the origin of the universe to the ultimate fate of the cosmological objects. However, little by little, scientists realized that the two theories were not sufficient to explain some observed phenomena and features. Thus, they had to develop a new theory which could explain those that could not be explained by quantum physics or theory of relativity. The first attempt was the standard model which explains all the fundamental particles, out of which matter is made of. The model also explained all the fundamental interaction in the universe with one exception; the gravitational interaction was not included in this standard model. Therefore, the standard model is not a completely unified theory. It was realized that combining the gravitational interaction with other three fundamental interactions was difficult.

String theory is a theoretical model which is based on one- dimensional fundamental objects. These objects are known as strings as they are believed to be one dimensional. In string theory, strings can vibrate in different vibrational states. Even though strings are one dimensional, they look like particles as they vibrate. Different vibrational states of strings correspond to different types of particles of which mass, spin, charge, and other properties are adjudicated by the vibrational states of the strings. One of the vibrational states of the string corresponds to the mediating particle of gravitational interaction called “graviton.” Thus, string theory is considered to be a theory of quantum gravity. The string theory includes all the fundamental interactions.

The strings in the string theories may be either closed or open strings or both. One can start to develop a string theory from any type of these strings. If he wants to develop a string theory only for bosons, it is a bosonic string theory. A bosonic string theory explains all the fundamental interactions except matter. The bosonic string theory is a theory of 26 dimensions. But if someone wants to develop a string theory which is capable of explaining all the fundamental interactions as well as matter, a special symmetry between the bosons (force carriers) and the fermions (matter particles) called “supersymmetry” is needed. Such a string theory is known as a “superstring theory.” There are five types of superstrings theories, and they are still being developed. The latest revolution in the string theory is “the M-theory” which is still under development.

## Difference Between Higgs Boson and String Theory

### Basic Definition

**Higgs boson: **Higgs boson is the particle which gives other particles mass.

**String theory: **String theory is a theoretical model which tries to explain the way matter is made of, fundamental interactions, etc.

### Acceptability

**Higgs boson:** The existence of Higgs boson has been confirmed.

**String theory: **String theory is still under development.

### Other Viewpoints

**Higgs boson: **Some physicists believe that there may be more than one Higgs boson.

**String theory: **Several types of string theories exist.

* Image Courtesy:*

*“Calabi *yau*” By *Jbourjai* – Mathematica output – created by author (Public Domain) via Commons Wikimedia*

*“Elementary particle interactions” By en:User:TriTertButoxy, User:*Stannered* – en:Image:Interactions.png (Public Domain) via Commons Wikimedia*