Sunday, December 21, 2008

Ice Crystal Patterns on My Home Window

Today I was amazed by seeing the little funny crystals on the window of my home. The following picture show them.

From Guage Invariance Photoblog

What are these crystals?

My window has double pans, the outer one touches a freezing temperature and the inner one a comfortable high temperature of +25 Celsius. My living room heaters are right underneath that window, therefore the transmission of hot air around the window is high. Moist cools to water and gradually into ice on the outer glass.

When the outside temperature falls gradually, the water molecules have enough time to cool down less disorderedly and form a crystal. The water crystals are frosted based on the glass surface conditions. In fact, when a piece of glass is polished at the time it was made in the glass factory, or when we scrub its surfaceby soap or glass cleaners some hidden patterns are left on it. These patterns play an important role of being the main base to nucleate the way these frost crystals condensate and grow on the window.

The main question is where these symmetric flower patterns come from? To learn it, see here.

Below there are some more photo of my window:

From Guage Invariance Photoblog

From Guage Invariance Photoblog

From Guage Invariance Photoblog

From Guage Invariance Photoblog

Friday, December 19, 2008

Snow strom in Waterloo

Today, I was excited in the morning. Finally the moment of having a real snow storm in our city has arrived! Interesting, because this was the only way to see Navier-Stocks equations in front of your eyes, specially when winds are blown out from the edge of a building. You see how the smooth wind fronts get hurly and produces the little funny curly wind flows right after the edges.

I took some pictures in the university that I put here some.

From Guage Invariance Photoblog

From Guage Invariance Photoblog

From Guage Invariance Photoblog

From Guage Invariance Photoblog

From Guage Invariance Photoblog

From Guage Invariance Photoblog

Tuesday, November 18, 2008

Scientific inquisition

It is difficult to talk about the things that I like because you see them in my works. They are in my paintings, in my radio theaters, in my papers. It is easier for me to talk about things that I don't like. I mean I cannot describe what I like in words. They are more interesting than words.

But in all, I do not like to engage in telling some useless stories in my papers about towards this theory and that theory. I like to be mystified by physical world instead of ordering to the reality on how it should be. I don't like to arouse the readers of my papers emotionally or give them some advices about how should he or she study from now on. I don't like to belittle him or burden him with a sense of guilt that he or she is ignorant and there are a lot to learn before thinking about nature. These are things I don't like to read in papers written by others as well. I think a good paper is one that has a lasting power and you start to reconstruct it right after you leave reading it.

There are lots of papers that seem to be boring but they are decent pieces of science. On the other hand, there are papers written by sometimes famous people that nail you to your seat in your office when you read it and overwhelm you to the point that you forget everything. I have experienced this feeling in the near past and now I feel I am cheated. These are the well-written papers that took me hostage! I absolutely don't like the papers in which the scientist provoke his or her readers with some fake calculations that artificially describe what was raised by that great mind in a seminar as an imaginary problem of some imaginary concepts.

I have to confess there are some papers in my office right now that have made me doze off when I read them, but the same papers have made me stay up at night, wake up thinking about them in the morning and keep on thinking about them for weeks. Those are the kind of papers I like.

I have imaginations but there are differences between illusion and reality. Not everything I imagine will be found in nature even if they are linked to theoretical physics. I can't tell you what part of me is reality and what part is illusion, or why I've had this game of vacillation from reality to illusion and back to reality in my ordinary life, not necessarily as a physicist. The capacity to dream is the most important human characteristic, shared not proportionality but enough for each. Though all of us dream, only a very few of us can write it in the form of formulae.

Imagination is one of the most extraordinary gifts granted to human beings. But, why must we dream? I think, we resort to dreaming at times when we are unhappy with our circumstances. And how extraordinary is it that no dictatorship in research institutions can control it?

Obviously there is a scientific inquisition running in some of the academic research institutes even where freedom in science is being advertised from. However, it is surely true these only can affect the most boring part of science. No interesting part that really exists let the scientific inquisition control a true scientist's fantasies. They can throw you in a jail (i. e. a dark well) of ideas, but you still have the ability to live your sentence outside the prison without anyone holding you there. Through the imagination, you can pass over the insurmountable walls of stupid ideas without leaving any trace of yourself, and you can always go back. Now the question is, once out why we go back?

Friday, October 24, 2008

Entropy of a Research Center

In an interview with Martinus Veltman back to 1999 hosted in the Nobel Prize Organization website, Veltman talks about differences in the educational systems of Europe and USA in the first two minutes. It goes this way:

Interviewer: What was a difference between being a student today and the time when you were a student?

Veltman: It was less disciplined [then]. In my student era you could do nothing for a few years. And you start working again, and I liked that a lot and I did nothing for a number of years. But today in Europe, it is no more possible because they stop supporting you and so on. They made the system such that you cannot do it.

I am strongly in favor of a system in which someone can momentarily go out and later on come back again, for whatever reason; maybe he is not mature enough or maybe he wants to have other experiences. That was [possible] in a system of my time. Today, it is no more possible, it is very difficult.

Given that such a freedom is necessary to create new science, unfortunately what he says and we are experiencing is a lack of free-thinking in today's science.

I personally have no professional academic experience in my home country Iran to be in a University as a faculty member but from what I heard from friends, I think, this is still possible one can do nothing for a number of years without being kicked out of the University in Iran. I hope they keep up the good job!

However, there are some model research institutes in Iran that are supposed to percolate the body of Iranian science within universities and these Institutes seems to be very well disciplined. This is unfortunate because if anywhere else in the world must become more and more disciplined, this should be the other way around and the entropy should get raised inside research institutions. A scientist needs new ideas to be extracted from a Hurley burly of thoughts.

Tuesday, May 13, 2008

Gravity in small scales (Part 1 - Tradiational Gravity)

By: Mohammad H. Ansari

What sort of laws shape the universe? The answer is given by understanding two
things: 1) what is space-time, 2) what is the dynamics of space-time.

The first question has no unique answer. In fact, there could be many answers to it, among some of which are: metric fields, frame fields and connections, causal sets, causal sites, strings, topological fields, spin networks, etc. Usually any reasonable assumption for simplifying a physical system such as space-time is acceptable as long as its dynamics satisfies some physical facts. What makes a theory successful is mostly its dynamics.

So far there have been many different models for studying space-time dynamics in quantum scales; from perturbative to non-perturbative and also from continuum to discretized ones.

The traditional quantum gravity started with fixing a background metric and defining quantum effects as the perturbations of background metric. The diffeomorphism constraint is linearized and it appears to be solvable. This theory in this format becomes similar to a local field theory with two degrees of freedom defined at each point. The Feynman rules for constructing the diagrams are obtained from the Einstein-Hilbert Lagrangian coupled to matter using standard procedures of quantum field theory.

Comparing to other field theories, in this localized field theory of gravity the perturbative part of metric turns out to interact with itself on the fixed background by some additional derivatives. This suggests the interaction coefficient to be of length dimension.

Quantum field theory of gravity has an infinite number of complicated interaction vertices. Where the momentum of the internal loop propagator becomes arbitrary large the loop diagrams diverge. In other theories such as chromodynamics the similar UV divergences appear; however those theories are renormalizable. Renormalizability means that the divergences from high energy scales can be absorbed into the redefinition of original parameters appearing in the theory. However, in the quantum field theory of gravity, we cannot eliminate UV divergences in the original Lagrangian because the gravity coupling G carries dimension of length.

To be continued ...

Wednesday, April 16, 2008

The Intelligent Village

The following Bulgarian Animation by Donyo Donev explains one of the most common problems in quantum gravity papers for years now. Somebody makes a model. It contradicts a classical fact. It is modified. It breaks something. It gets modified. It is redone again and again for several times. Finally, the initial problem for whose solution the initial assumption was made is forced to be back to the theory. It is back and resolves some post-created problems but yet there exists the main problem there.

Wednesday, April 02, 2008

How to convert jpeg images into eps?

If you use windows to write LaTeX files (by editors like WinEdit etc.) you may feel that it is terribly hard to find an effective way to convert a picture with format jpeg, bmp, etc into the appropriate format of LaTex, which is eps.

If you google it you will get many softwares which are mostly non-free. I tried several of them and faced with funny problems. For instant when you convert a picture in one of them, it does it on its trial version but it stamps (!) the outcome eps picture with a very large signature of their company, which makes the picture useless. Another software convert it with very poor quality in its trial version, etc.

I found two simple way to overcome this problem.

First method:

1- First install GSview and GhostScript from this page on your windows.

2- Download the humble, effective and small software called "jpeg2ps" that let you convert jpeg to eps with acceptable quality (and you can increase its quality manually). jpeg2ps is available from here and many other sites, notably CTAN mirrors.

UPDATE: If you are lost and do not know how to work with jpeg2ps software in Windows, read my jpeg2ps pedagogical helps on it.

Second method:

1- First install GSview and GhostScript from this page on your windows.

2- Install the driver of a Postscript printer (denoted by a "PS" at the end of the printer name. This can be done as follows: Start -> Control Panel -> Printers -> Add printer. Press next a couple of times until you reach the page where you can choose between different manufacturers. Choose a Postscript printer.) I have chosen the printer "Apple Color LW 12/660 PS."

3- Now come back to My Computer and find the picture you want to convert. Right click on it and press Edit, or you Open With - > Paint. If you do not know what Paint is, go to Start -> Accessories -> Paint. Now, File -> Print. Choose the printer you just installed. Tick on "Print to a file." Click on the printer Preferences - > Advanced. Where there is "PostScript Option" in the tree diagram, click on the little + sign next to it such that you see its sub-branches. In the "PosScript Output" change the default which might be Optimized for Speed into "Encapsulated Post Script (EPS)." You also can play with other features and properties to change the quality of the outcome EPS picture. Then OK everything and choose a name for the outcoming file. It will be created at the same foldr as the original file was in.


More information:

How to work with jpeg2ps software in Windows? (Gauge Invariance)