What is string theory?

Answer 1

It is a theory that looks at physics differently to try and combine General Relativity with Quantum Mechanics, something the Standard Model (the most widely accepted theory of how the universe work) has not been able to do. Instead of using zero dimentional point particles, it uses one dimentional strings which cleans out some of the complications with the Standard Model. However, most of its predictions have yet to be verified, so its not as widely accepted or as successful as the Standard Model. The amazing thing about String Theory (actually, it is a whole bunch of theories) is that it predicts Gravitons, something the Standard Model has been trying to do for very long but hasn't been able to.

Answer 2

String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. String theorists are attempting to adjust the Standard Model by removing the assumption in quantum mechanics that particles are point-like. By removing this assumption and replacing the point-like particles with strings, it is hoped that string theory will develop into a sensible quantum theory of gravity. Moreover, string theory appears to be able to "unify" the known natural forces (gravitational, electromagnetic, weak and strong) by describing them with the same set of equations.

No experimental verification or falsification of the theory has yet been possible, though the Large Hadron Collider near Geneva, Switzerland may produce relevant data.

Studies of string theory have revealed that it predicts not just strings, but also higher-dimensional objects (branes). String theory strongly suggests the existence of ten or eleven (in M-theory) spacetime dimensions, as opposed to the relativistic four (three spatial and time).[1]
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Answer 3

A string theory is one that includes a fourth dimension as one of the measuring unit known as 'time'.
A three dimensional figure is well known to every one as we come across every now and then.
In this case the time considered for visualising the dimension is negligible or ignored whereas one can not ignore the fact of time when it comes as a question of visualising the heavenly bodies.
No heavenly body is in its place as we see now.
What we see now may the position of the heavenly body a million years back.
Here a fourth dimension known as 'time' becomes a string between the present position and the apparent position.
This is how a complecated string theory is developed and it has not become practical for common scientist.
The string theory in computer term is different from what I explained here. That is another net within net in computer language that has nothing to do with fouth dimension.

Answer 4

String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. Due to this, string theory avoids problems associated with the presence of point-like particles in theories of physics and helps to develop a sensible quantum theory of gravity. Moreover, string theory appears to be able to describe the known natural forces (gravitational, electromagnetic, weak and strong) with the same set of equations. Studies of string theory have revealed that it predicts not just strings, but also higher-dimensional objects (branes). String theory strongly suggests the existence of ten or eleven (in M-theory) spacetime dimensions, as opposed to the relativistic four (three spatial and time).[1]

Answer 5

It's a sexy new theory that captured the imagination of the physicits in about 2004.
It speaks of a multidimensional world. The world we live in consists of 4 dimensions, the three axes and time.
But according to this theory there are 11 dimensions. It goes to the level of atoms and abolishes the belief that quarks are the fundamental units. It says that the fundamental units are strings are are present in huge number inside the quarks.

Einstein beleived in unification of the universe, one theory to rule them all, one theory to explain it all. There are 5 types of forces in the universe gravitational, electronic, magnetic, strong nuclear, and weak nuclear. The magnetic and electrostatic were combined by Maxwell, by his well known equations. Quantum theory combined both nuclear and electromagnetic.
Now this new babe string theory claims to combine all the forces under one theory. The basic mathematics governing the behaviour of 'strings', the fundamental particles of this theory is "THE GAMMA FUNCTION". It represents the behaviour of a string and that is can move in 11 dimensions.

Answer 6

Think of a guitar string that has been tuned by stretching the string under tension across the guitar. Depending on how the string is plucked and how much tension is in the string, different musical notes will be created by the string. These musical notes could be said to be excitation modes of that guitar string under tension.
In a similar manner, in string theory, the elementary particles we observe in particle accelerators could be thought of as the "musical notes" or excitation modes of elementary strings.
In string theory, as in guitar playing, the string must be stretched under tension in order to become excited. However, the strings in string theory are floating in spacetime, they aren't tied down to a guitar. Nonetheless, they have tension. The string tension in string theory is denoted by the quantity 1/(2 p a'), where a' is pronounced "alpha prime"and is equal to the square of the string length scale.
If string theory is to be a theory of quantum gravity, then the average size of a string should be somewhere near the length scale of quantum gravity, called the Planck length, which is about 10-33 centimeters, or about a millionth of a billionth of a billionth of a billionth of a centimeter. Unfortunately, this means that strings are way too small to see by current or expected particle physics technology (or financing!!) and so string theorists must devise more clever methods to test the theory than just looking for little strings in particle experiments.
String theories are classified according to whether or not the strings are required to be closed loops, and whether or not the particle spectrum includes fermions. In order to include fermions in string theory, there must be a special kind of symmetry called supersymmetry, which means for every boson (particle that transmits a force) there is a corresponding fermion (particle that makes up matter). So supersymmetry relates the particles that transmit forces to the particles that make up matter.
Supersymmetric partners to to currently known particles have not been observed in particle experiments, but theorists believe this is because supersymmetric particles are too massive to be detected at current accelerators. Particle accelerators could be on the verge of finding evidence for high energy supersymmetry in the next decade. Evidence for supersymmetry at high energy would be compelling evidence that string theory was a good mathematical model for Nature at the smallest distance scales.

Answer 7

according to this theory everything in the universe is made up of strings means build by combinations of strings and the behavior of the body formed by string depend on the frequency of their vibration