Sunday, August 28, 2011

Randomness and its constant uniformity

Random - How do you perceive it? Chaotic? Disorderly? Higgledy-piggledy? For most of us, these are the defining words for "Randomness". When you think about it, sometimes anything random seems to exhibit the most consistent behaviour. I thought of it and have come up with certain examples, the cases in which randomness is not really random!

1) A non-crystalline material
A crystal has the atoms arranged in an orderly manner. Hence, it is anisotropic - that is, it does not exhibit the same characteristics (Physical, optical, etc) in all the directions - irony. But a non crystalline material exhibits properties that uniform regardless of the direction. 

2) Concrete
My prof once asked me why they add small stones to cement and mix it thoroughly. Why? Its because they want the position of stones in the cement to be as random as possible. Again why? They want it to be "Isotropic" so that it does not have any planes or lines of weakness which will be there when the stones are arranged in an orderly way. It can be better explained with a potato and a wooden log. Try cutting a potato in different directions and you'll find it the same effort is required for all the directions. But thats not the case with a wooden log. Its easier to cut the log in the longitudinal direction than the transverse directions because the fibres are lined along the longitudinal direction (An orderly arrangement)

3) Sampling
For quality tests in industries to surveying people, always a "random sample" is taken. Why? It gives a  result that more or less describes the characteristics of the whole group of entities. No survey is accurate only when a particular closely related section of people are answering the questionnaires. 

4) Chemical reactions
Most of the chemical reactions take place when the reactants are "uniformly"  mixed. So, what is this uniform mixture?? Reactant A placed on top, B in the middle and C at the bottom? No, they call it uniform when the mixture is chaotic and random. For that matter, any uniform mixture is one that is random.

Entropy the term that measures the degree of randomness is something so important in this universe. Want to know why? Read this.

No comments:

Post a Comment

Please leave your comment here.