String theory is a concept developed by physicists trying to explain the fundamental nature of matter and space. The concept has various interpretations, but has the ability to explain the phenomenon of existence. Since the most fundamental particles do not exhibit the properties of matter that bigger objects have, some scientists consider them non-dimensional (Van Proeyen 12).

This means they do not have width, length or depth. General relativity holds that all matter and space exists in four dimensions. Depth, width, and length of all matter and space exist through time (Kane 46). This means that time is the fourth dimension.

Distortion of time results in distortion of the other three dimensions, which are the dimensions of space. This is quite different from Newtonian physics, which does not consider time a dimension.

However, practical science is based on Newtonian physics. Although the theories of relativity are not applicable in practical science to a satisfactory extent, they are accepted as the true explanations of the phenomenon of existence (Zwiebach 16). The effort to understand the seemingly dimensionless nature of fundamental particles and the four dimensional nature of matter and space in one theory has led to development of string theory.

According to string theory, there are other more fundamental dimensions contained in the four dimensions of physical existence that are normally experienced. The additional dimensions add to the four known dimensions to make eleven-dimensional world (Van Proeyen 41). Compression of these dimensions into the fabric of universal existence makes them undetectable by any physical means. However, several mathematical models have been used to prove their existence and the nature of their interaction.

The string theory explains the manner in which the one-dimensional basic particles interact to result into a four dimensional existence. Matter, space, and time are a yield of this interaction. Fundamental particles are made up of one-dimensional strings, which interact with unidirectional membranes to create a particle (Zwiebach 18). Gravitational force, a phenomenon that has not yet been understood by scientists is explained as a product of string interaction. Scientists have already developed a mathematical form for gravity.

The wave nature of matter is a part of the theory explaining how the fundamental particles exist. One certain kind of wave motion is responsible for all behaviors of matter and space. The string theory is the only theory that offers a single explanation to the nature of matter and space. However, since the theory proposes the existence of dimensions that cannot be physically assessed, it is not possible to test its integrity.

Other challenging theories have endured criticism to emerge as possible alternatives to the string theory since they can be tested, and have an observable fundamental constant. Advocates of the string theory believe that a universal constant exists within the string theory, but a mathematical proof has not been developed yet (Zwiebach 22). This constant and a testing mechanism for the string theory are the only remaining constituents that can establish the theory as a proven fact.

The nine-dimensional vibration of each string is unique and yields the properties of fundamental particles. The ends of a single cosmic string are joined such that an indefinite loop is formed. Forces of interaction attract the string towards the centre of the loop (Van Proeyen 45). This action is responsible for the appearance of fundamental particles as singular points with no dimensions at all.

The dimensions of the physical world are fixed in certain directions according to Newtonian physics. In string theory, dimensions are mathematical representations with no directional properties of the three spatial dimensions. Moreover, these dimensions are compressed into a manifold such that they are not testable by any physical means (Zwiebach 30). This is attributed to the infinitesimal distances that represent the particular dimensions.

Since mathematics is largely based on spatial dimensions, there is no method to test the presence of cosmic strings within the current mathematical scope. Several propositions assume that the invisible dimensions are responsible for the unexplained forces that are observed in nature.

Electromagnetic wave is assumed to be made up of a certain combinations of the dimensions. Gravity, a force whose presence is established by empirical evidence only, is also considered a product of the additional dimensions (Van Proeyen 15). This is why gravitational force and its characteristics such as inertia do not seem to emanate from any one physical location.

The string theory presents a single explanation for existence of all matter and space. Through the string theory, it is possible to understand the relation between space and time. The relative relationship that makes time similar to space can be understood through string theory. The small dimensions of the strings make it impossible to investigate the pattern in which they are woven together (Van Proeyen 7).

If a definite pattern in which the strings are woven is identified, it is possible to understand the construction of forces and the difference between various forces. However, the ability to understand the fundamental constituents of time and force can discredit all conventional physics, as it is understood today (Zwiebach 74). Such knowledge could also result in breakdown of phenomena such as the construction of time towards the future.

## Works Cited

Kane, G. L.. *Perspectives on supersymmetry II*. Singapore: World Scientific, 2010. Print.

Van Proeyen, Antoine. “A First Course in String Theory.” *Intensive Theoretical Studies* 5.3 (2008): 5-60. Print.

Zwiebach, Barton. *A first course in string theory*. New York: Cambridge University Press, 2009. Print.