Relativity In Words Of Four Letters Or Less

This is an interesting writing on Relativity.

Relativity in words of four letters or less

Academic Earth - University Lectures

Recently, I found a link to an Introduction to Solid State Chemistry course that is OpenCourse. The lecture I listened to was on Diffusion and the professor showed the connection between mass transport by diffusion, Fourier's first Law, and Ohm's Law which Fick, himself, reported on about 150 years ago. Cool.

This is provided at Academic Earth and there are many subjects and many lectures from physics to the bible. Pretty impressive. Have a look.

Scientific Software Developer Mantra

"Care enough to be a better scientific software developer today than yesterday."


For several months now, I have been trying to word a personal mantra for a scientific software developer (SSD). There has been about half a dozen mantras that I have been tossing around without settling on anyone mantra. They all were similar and the basic idea started with was, "Get better each day." Which in life is a good mantra.

So I decided to settle on the one above and to use it until a more polished one emerges (refactoring for emergent design.) It may seem too wordy for a mantra but it conveys how I want to behave as a SSD. Of course, if I was doing other parts of computational physics then computational physicist could be inserted easily.

Recently, Dan Pink posted a video called "Two Questions" about two questions that could change your life in 2010. I thought question #2 was coincidentally appropriate for this post.

Follow-up To Where Is Software Development Really Learned?: Stroustrup's Article

A few months ago I pondered Where Is Software Development Really Learned? And my thoughts were, "We learn on-the-job and by professional development but not often in school. Even for many CS majors."

Recently, Bjarne Stroustrup wrote on a similar topic in What Should We Teach New Software Developers? Why?

Again, what jumps out at me in Stroustrup's article (especially in The Problem section) is where is software development really learned? One of his conclusions was similar to mine (internships and mentoring in industry along with formal education) in that academia and industry need to bridge this gap.

Interesting article.

Simulation Model: Stage Four - Verification

Thinking about Pople's Quantum Chemistry Models (or in more general Simulation Models), where five stages may be distinguished as:

1) Target
2) Formulation
3) Implementation
4) Verification
5) Prediction

I got to thinking about the fourth stage:

4) Verification
The next step is to test the model against known chemical facts to determine whether the target has been achieved. If quantitative accuracy is being sought, this can be done by various statistical criteria such as the root-mean-square difference between the results of the theoretical model and experimental data. In selecting such a dataset, it is important to make it as broad as possible, while limiting it to experimental facts known to be of high quality. If the results of such a comparison do meet the target requirements, the model may be said to
be validated.

and how this applies to almost any other type of scientific endeavor.

Can stage four be skipped? In doing so how do we know stage five (Prediction) results are correct? How do we start problem solving if stage five results are incorrect? If stage five results are correct then how do we know that several wrongs did not make a right?

There are many unanswered questions and there could be even more depending on the situation.

Without stage four, I would not be confident in the results of stage five for doing predictive science. Could one start from scratch and reproduce my results without stage four? Perhaps but most likely it would be fortuitous and if several persons tried to reproduce the results then most likely my results would be found out to not be very reliable. Without each stage where is my accountability?

Interestingly enough, these five stages could be associated (or at least have direct analogies) with doing experiment too. To take it even a step farther, these five stages could be said to be the outline of the scientific method.

Science is built in steps and with each step confidence and reliability is built. Without stage four are we really doing science or are we just playing around wasting time and money?