20 November 2011

What is String Theory?

For the past decade, physicists all over are focusing their attention on string theory. But what is string theory?

A simple explanation to string theory is that it is the basic fundamental building block for everything. When all the matter in the universe is broken down to its most basic component, it will be tiny particles that look like strings; String Theory.

That basically is the most simple answer to what String Theory is. But going one step further is where things get really complicated.

When we look an object, we know it is made up of molecules. These molecules are broken up into individual atoms. These atoms are then made up of protons, neutrons, and electrons. Protons and neutrons are made up of quarks. These particles have already been discovered by scientists.

According to string theory, these quarks (including the electron) can still be broken up into smaller units. These are tiny one dimensional particles called "strings". These strings vibrate in different frequencies which dictate what kind of particle they make up. Basically, in string theory, a neutron and and a proton are made up of the same material.

What string theory suggests is that the whole universe is made up of these strings. But it doesn't just stop there. String theory opens up more complex questions.

Based on the math, for these strings to exists, the universe has to be made up of not just three dimensions, but ten dimensions. Ten dimensions plus one dimension of time.

Video: David Tong, a physicist at Cambridge University, explains String Theory

Why is string theory important?

Presently, there are four known forces existing in the universe. These forces are gravity, electromagnetic force, strong nuclear force, and weak nuclear force. Each of these forces are governed by its own set of rules and equations. Some of these rules contradict or are even not acknowledged by the others.

For example, gravity according to Einstein is transmitted through the dimension of space. But what about electromagnetic force? What dimension does it exist in?

String theory attempts to unify all these forces into one theory. The theory of everything. Where all the forces of nature can be explained in one equation. That is what string theory is all about.

Video: Brian Greene explains String Theory. Highly recommended

To get real world implications of string theory, we look at the history of physics.

When we discovered gravity and understood this force, we entered the industrial age.

Electromagnetic force welcomed the electronic age with electricity. With the knowledge of the strong and weak nuclear forces, we were brought into the nuclear age with nuclear power.

Learning string theory, will unify all these forces and would probably usher in a new age in human civilization. How will it actually impact us specifically? We still don't know. String theory is just still that. A theory.

It is theorized that the size of a string is of the Planck scale which is 1.616252×10−35 m. These strings are so small that if we can magnify a hydrogen molecule to be as big as the milky way, these strings would still be the size of a width of a human hair. The Large Hadron Collider and other experiments are being conducted to verify the existence of strings.

There are also other theories that attempt to unify the forces of the universe without using strings. One such theory is Loop Quantum Gravity. This will be the topic of a future article.

Video: Michio Kaku, co-founder of Field String Theory explains why the universe has 11 dimensions

Related Links

What Is Antimatter?
What Is The Higgs Boson And Why It Matters
Speed of Light Theory To Be Challenged Again
Project Sixtrack: The Large Hadron Collider and Your Computer
Whats New @CERN 07 Nov 2011
Particles Travel Faster Than Light Again
Whats New @CERN 06 Dec 2011
CERN Press Release: Higgs Particle Search Status Still Inconclusive
Bartenders Use Physics in Mixing Cocktails
Danceroom Spectroscopy: Quantum Physics on the Dance Floor.