Strings as Particles

 

Particles in string theory are one-dimensional threads which we can see only the cross section of it (as a point). Point particles in quantum mechanics on the other hand, do not posses any dimension.

The strings in the String Theory are either loops or free end. These elements with their different vibration patterns can represent different energy level. Then the energy can be translated as mass of the particle. One expects that the liberty to choose any vibration should help us to find a particular vibration which matches at least one of the known particles. The problem is, after three decades of extensive research, there was no resemblance between particles in string theory and the actual sub-atomic particles.
Then the next assumption came to rescue. If extra-dimensions have different sizes, then the loop’s vibration in different dimensions with different sizes will open a new possibility to explore. Maybe if we find the right size for each dimension, we can come up with vibrations that resemble the common particles. So the legend continued.

Branes as Particles

 

Even if particles arise as oscillation modes of strings, string oscillation don’t necessarily account for all particles found in nature. Therefore, Andy Strominger and colleagues at Santa Barbara came with another idea. They proposed that in certain space-time geometries the branes give rise to new types of particles. These are called p-branes. They speculated that since branes can come in different shapes, forms and sizes, we can assume a very tinny curled up brane acting as an independent object that interact with its environment. Therefore, assumed wrapped branes can be candidates for the particles that are not found in string form.
Then there were problems of complicated calculations so they assumed that there are symmetries in the whole elements of the universe. Calculations by using symmetry principles were easier and solvable.

The strings are so small that can not be detected so the whole idea could not be tested and therefore could not be proved. Then Super-symmetry came to picture and the assumption that there are much bigger particles which are symmetric to small and not observable strings. This assumption created the hope that sometime in the future we can observe the bigger partners and prove the conjectures.

 

Brian Greene himself questions the string particles:

 

“Just as string theory shows that the conventional notion of zero- dimensional point particles appear to be a mathematical idealization that is not realized in real world, might it be the case that an indefinitely thin one dimensional strand is similarly a mathematical idealization.”1

 

String of Assumptions

 

The string of assumptions does not stop here. The complexities imposed by confining ourselves to space-time arena, led the string theorists to even believe in possibility of existence of as many as 10⁵⁰⁰ different worlds. Thus they indorsed the multiverse concept. The multiverse idea advocates the presence of many parallel worlds.

With so many assumptions, one can find a solution for any kind of puzzle. Imagine you have the liberty to redesign a crossword puzzle by moving around the black squares to your will and select your own words to place in the squares. Moreover, you take the liberty to choose the shape and the size of the puzzle. Solving the puzzle will get very easy this way. As the problems aroused more postulations came to rescue. Now we have built a fascinating theory that is mind wrenching and a good challenge for the boys to entertain themselves. Is this waste of talents and knowledge of brilliant physicists and mathematicians?