The Universe: How many dimensions are really possible?

We all are probably aware of the three dimensions that our daily lives revolve upon. Those that define the length, width, and depth of all the objects in our universe. (i.e. the x, y, and z axes, respectively). Beyond these three visible dimensions, scientists believe that there may be many more ruling the positions and the states of various things in our daily lives.

Albert Einstein, in his general theory of relativity, explained the concept of a four dimension universe with time being the Fourth dimension.Since, we all know that time always flows in the forward direction, The three dimensioned space and the uni dimensioned Time make up a four dimensioned Universe. That is the Universe consisting of space-time is of four dimensions.

Time is often thought of as the fourth dimension. Time plays a key role as a separate dimension in the mathematical formulations that define almost every physical laws and theories such as general relativity and string theory. However, The qualitative behavior of time as the fourth dimension is debatable.

Now, Talking about more probable dimensions which all are explained by string theory, a well known theory that is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings, It describes how these strings propagate through the space and interact with each other.

On distance scales larger than the string scale, a string looks just like an ordinary particle, with its mass, charge, and other properties determined by the vibrational state of the string. According to the string theory, one of the many vibrational states of the string corresponds to the Graviton. Graviton is a quantum mechanical particle that carries gravitational force. Thus, string theory is also a theory of quantum gravity.

Often marketed as one of the unsuccessful attempt of Albert Einstein, he once attempted to join and relate all the Physical forces acting on the universe by a single formulation called theory of everything.It is the theory which he could not formulate even after spending more than last 30 years of his life until eventually being dead.

However, many of the scientists today are working on the same project of confining the universe in a single mathematical formulation also called ” Theory of Everything”. The String theory could be a potential “theory of everything”, uniting all the matter and forces in a single theoretical framework, which describes the fundamental level of the universe in terms of vibrating strings rather than particles.

According to the string theory, a total of 11 dimensions are possible in the universe ( 10 of universe and 1 of time ) and each one of them is very important for the Theory of Everything.Though Scientists are applying all of their efforts and knowledge to find out all those possible dimensions, but nobody has succeeded yet. Hence based on all the scientific proofs and observations till now, we are living in the universe of only four dimensions.

Though Our basic understanding of physics makes this hard to process, string theorist Brian Greene has done a great job of framing the concepts in the terms most people can understand. In his 2005 TED Talk, Greene compares these invisible dimensions to the cables connected to telephone poles.

Quoting him, ‘From a window, a wire looks like a one-dimensional line. But if we were to study it up close we’d see that the cord is actually round, making it three-dimensional. No analogy comparing non-observable dimensions to objects in the observable world can ever be perfect, but this illustrates how something so fundamental to reality could be hiding in plain sight.’

Although from the above we can conclude that there are more than the 3 or the 4 dimensions, but the fact is that our Universe cannot have more than 11 dimensions. Because of the self consistency, they become unstable and collapse back down into 11 or 10 dimensions. Hence, there are more than four dimensions but are limited to 11.

The ted talk given by Brian Greene and referenced above is given below:

Article by: Radhakrishna Bhandari