String Theory, The Ultimate Theory?

In the standard model of particle physics, particles are as points move through space, the pursuit of a line with the name "World online. To take account of the different interactions in nature observed, the particles with more degree of freedom to their position and velocity, such as mass, electric charge, color (this is the "cargo" in conjunction with the strong interaction) or spin.
The standard model has been in a framework, known as Quantum Field Theory (QFT), which gives us the tools to build both in line with theories of quantum mechanics and special relativity theory. With these tools, theories have been built, describing with great success three of the four known interactions in nature: electromagnetism and the strong and weak nuclear forces.
It was a very successful agreement between electromagnetism and the weak force has been reached (electric Weak theory), and promising ideas put forward to try to strong force. But unfortunately the fourth interaction, gravity, as defined by Einstein's General Theory of Relativity (GR), does not seem to fit into this scheme. Whenever you try to apply the rules of

QFT GR to get results that make no sense.

The usual areas of the general theory of relativity and quantum mechanics are quite different. General relativity theory describes gravity and thus is usually limited to the largest and structures, including the massive stars, galaxies, black holes and even in cosmology, the universe itself quantum mechanics is very relevant in the description of the smallest structures in the

universe, such as Electrons and quarks.

In most normal physical situations, either general theory of relativity and quantum mechanics is a prerequisite for a theoretical understanding, but not both. However, there are extreme physical conditions, which require these two fundamental theories for an adequate theoretical treatment.

Prime examples of such situations are space-time singularities, as the central point of a black hole or the state of the universe shortly before the Big Bang. These exotic physical structures with enormous mass scale (and thus the general theory of relativity) and extremely small distance scales (quantum mechanics).

Unfortunately, the general theory of relativity and quantum mechanics are not compatible: any calculation, which also uses these two instruments, and the income nonsensical answers. The origin of this problem can be attributed to equations, which are badly behaved when particles interact with each other minutes scales in the order of 10-33cm - the Planck length.
Another problem with this model is that you assume that the existence of different forces and their carriers. Einstein hoped that a "unified" theory in which all the known forces would be composed of one single in a certain way. Electricity and magnetism used to be thought of as two forces, but now we know these are two different aspects of the same (electro-magnetic). Could the same kind of agreement to hold the four forces, which today are distinguishable?
String theory is currently the most promising example of a candidate unified theory. We do not yet know whether it correctly describes nature, but it seems to be a theory, largely describes a world similar to ours, and is endowed with beauty and consistency to an astonishing degree.

Strings
The physical idea is very simple. Instead of many types of point-like elementary particles, physicists postulate that in nature there are a number of individual string object. The string is not "everything" but it is a very simple and other things are made. As for the musical strings, this basic string can vibrate, and each vibration mode can be used as point-like elementary particles, as well as the Modes of a musical string perceived as their own notes!
String theory solves the problem of deep incompatibility of the two fundamental theories (GR and QFT) by modifying the properties of the general theory of relativity, if it scales in the order of the Planck length. Modern accelerator can only probe scales at a distance about 10-16cm, and thus these loops of string instruments seem to be objects.

However, the string theoretical hypothesis that they actually are tiny loops, dramatically changes the way in which these objects interact in the shortest distance from scales. This modification is allowed, what the gravity and quantum mechanics into a harmonious unit.
There is a price to pay for this solution, however. It turns out that the equations of string theory are self-consistent only if the universe contains, in addition to the time, nine spatial dimensions. Since the gross conflict with the perception of three-dimensional space, it might seem that string theory must be discarded. However, this is not true.

Several theories String
However, it is more than a theory. These theories are classified, depending on whether or not the strings are required closed loop, and whether the particles range fermions (particles, does matter). To fermions in string theory, there must be a special kind of symmetry called supersymmetry, which means for every boson (particles that transmits a force), there is a fermion. So does the supersymmetry particles, the forces to the particles that make up matter.
String Theory, which deals with bosons are not only more popular because they require 26 space-time dimensions and a particle with imaginary mass of the tachyon. There are a whole series of superstring theory, which is mathematically only require the ten dimensions. A few of the differences between them are closed-loop theories and others only with closed loop, the pause in open strings.

Massless theories with fermions only spinning one way (chiral) and string theories, the heterotic, which means the right and left moving strings. Different combinations of the above characteristics make us with 5 plausible (mathematically) theories.

M-theory
There was a difficulty in the investigation of these theories: physicists and mathematicians do not have instruments to the theories of all possible values of the parameters in the theories. Each theory was like a big planet, which we knew only a small island somewhere on the planet. But over the last four years, techniques have been developed to the theories more thoroughly, in other words, to travel around the lake in each of these planets and find new islands. And only then became clear that these five string theories are actually islands on the same planet and not different! There is an underlying theory of string that all theories are just different aspects. This was called M-theory.

One of the islands was found that in the M-theory planet corresponds to a theory that life is not at 10 but in 11 dimensions. This seems to be telling us that M-theory should than 11 dimensional theory that a 10 dimensional in some points in their area of parameters. Such a theory could have as a fundamental goal of a membrane, in contrast to a string. Like a drinking straw seen at a distance, the membranes would look like if we strings curl 11 Dimension in a small circle.