String Theory

When as a child i read a book आकाशाशी जडले नाते (meaning got connected with sky) and got very much interested in astrophysics, cosmology . After that i took computer science as career option but sometimes i love to visit my older interest and read some stuff about it.
Today i watched a very interesting ted video about String theory . Brian Greene is one of the great physicist of our time and he is also prolific speaker who can simplify something like string theory which you and i can understand at least conceptually. He takes us on path about how these theories came into existence . Newton explained much about gravity but he could not explain certain things like how and why it is there. Einstein attempted to solve the question by trying to come with Unified theory. He added 4th dimension as time along with three dimensional space around us. Then came Kaluza who tried to explain the question raised by Einstein's theory by adding one more dimension in space. He tried to add one dimension and see what he gets and after solving the equations he got famous electromagnetic equation so he was very thrilled that he found unified theory. The speaker tries to explain how string theory is related to this .
We all know everything is made up of molecules which are made up of atoms which in turn can be divided into electrons ,protons & neutrons . This can be further divided into quarks. String theory takes this theory one step further and explains how this can be thought of divided into strings vibrating in different dimensions causing everything to be the way it is in this universe. But the problem with String theory is it can be applied practically if we consider only 3-4 dimensions of space. If only we think of 10 spatial and one time dimension string theory can be practically to understand the Universe. And that might suggest there are more dimensions out there.
If they are there why can not we see it ? Simply because the dimension might be very very small that we can not see it which is possible as we are not always able to see things which have already proven to be there. How can we 'look' for such dimensions then ? Brian Greene tells us that in coming years (may be 5-6 ) we might be able to come up with experiments which might detect (or prove it does not exist) other dimension in space. One of the experiments can be large hadron collider. They are trying to collide particles travelling around speed of light and the hope is that when they collide some mass might get converted into energy and escape into other dimensions. We can measure this by the loss of mass + energy. This might prove the existence of other dimensions.
The speaker also tries to explain that more or less in 20 very important physics constant we can explain many things in universe. But we do not know why these constant have those values that they have but one thing is certain Universe as we see it today will not be same if those constants had different value. And so its likely that other dimensions are there and we are not able to 'see' them .
Frankly speaking anything more than 3 dimensional in space starts becoming complex to me , so i am not going to go in much details of String theory but just to have general idea of what are those basic questions for Unified theory and how scientists are trying to come up with theories to explain Universe, everybody should watch this video.