# What is String Theory?

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String Theory is a mathematical theory that tries to explain certain phenomena which are not currently explainable under the standard model of Quantum physics. String theory is a "work in progress" theory in particle physics that attempts to bring together Quantum mechanics and Einstein’s Theory of Relativity. It is a challenger for the “Theory of Everything” (TOE), a manner of describing the known fundamental forces and matter in a mathematically complete system.

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### What is the History of string Theory?

Prior to string theory, sub atomic particles were envisioned as tiny balls or points of energy. String theory works on the premise that the tiniest sub atomic bits that make up the elements of atoms actually behave like vibrating strings found in guitar or violin. String theory was originally developed during the late 1960s and early 1970s in an attempt to explain some inconsistencies with the energy behavior of hadrons and other fundamental particles of physics.

The strings of String theory are so small that Physicist Brian Greene has postulated that if a single atom were enlarged to occupy the footprint of our solar system, a string would still be no larger than a tree. Since the tiny vibrating strings are responsible for the properties of all matter, the cosmos has been linked to a cosmic symphony of super strings. While the analogy of strings on a guitar might seem appealing, the strength of string theory is that it accounts for all 4 known forces in one elegant theory. These fundamental forces are gravity, electro magnetism, strong nuclear, and weak nuclear forces.

### What are the basics of String Theory?

At its core, string theory uses a model of one dimensional string in place of the particles of Quantum physics. These strings the size of Planck length (10-35 meter) vibrate at specific resonant frequencies. Some recent versions of string theory have found that the strings could have a longer length up to a millimeter in size which would mean that experiments could detect them. The formulas that result from string theory predict more than 4 dimension (10 or 11 in the most common variants, though one version needs 26 dimensions), but the extra dimensions are “curled up” within Planck length. In addition to the strings, string theory contains another type of fundamental object called a “Brane”, which can have many more dimensions. In some “Braneworld scenarios”, our universe is actually “stuck” inside a 3-dimensional brane, called a 3-brane.

### What are the Variants in String theory?

• Bosonic string Theory: The first String theory which focused only on Bosons, the subatomic particles which obey Bose-Einstein’s statistics.
• Super String theory: The variant of string theory incorporates fermions and super symmetry. There are 5 independent super string theories. They are Type 1, Type 2A, Type 2B, Type HO and Type HE.
• M-Theory: A superstring, proposed in 1995, which attempts to consolidate all the above said types as variants of the same fundamental physics model.

### What is the latest research in String theory?

At present, string theory has not successfully made any prediction that cannot be explained through an alternative theory. Although it hasn't be proven (or discarded), it has mathematical features which give it great appeal to many physicists. A number of proposed experiments might have the possibility of displaying string effects. The energy needed for many such experiments is not currently obtainable, although some are in the area of possibility, in the near future, such as possible observations from black holes.

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