Reply #43: I'm Curious About How Cells Divide

[jberryhill]

My background is in physics and engineering. I know practically nothing about biology.

What I do know about biology, in fact, is that I know practically nothing about it.

I've also done some teaching, and I think the biggest lie told by teachers everywhere is "There is no such thing as a stupid question." I'm of the opinion there is. Maybe not "stupid questions", but questions which are themselves simple, but belie an ocean of ignorance in their superficial simplicity - i.e. the assumption that all simple questions have simple answers.

Asking "Why is the sky blue?" is a simple question. The answer is stunningly complex. If a child asks the question, I am not going to go into a semester course in electromagnetics in order to lay the foundation to understand Raleigh scattering.

Why is the sky blue? Because the number 4 appears next to a greek letter in this:



Are you going to tell that to a kid? No. You will tell the child "Because light is made up of a lot of colors, and the blue part of the light is bounced around more by air than the other parts of the light are" or something like that. In fact, most adults think it has something to do with refraction because they are familiar with the way a prism splits up light. That has nothing to do with Rayleigh scattering and in fact most adults have no freaking clue why the sky is blue. Those that think it has something to do with refraction - i.e. most that think they know why - are wrong.

But if you ask me to tell you, an adult, why the sky is blue, then I'm more likely to say "Rayleigh scattering". And if you don't like the answer, it is not because of some lack of curiosity on my part - because you are perfectly capable of going off and learning about it on your own.

I'm not curious about why the sky is blue. I know why, and I know the answer is actually quite complicated, and is not going to be really understood unless you have a foundation from which to understand the mechanism by which it occurs.

Now, your assumption in this and two other threads is that there is a "simple" way to model ejected debris from a failing structure comprising thousands of interconnected components stressed to the breaking point. Elsewhere in one of threads, you didn't even notice the dripping sarcasm from someone whose answer amounted to "sure, if you don't mind dealing with a zillion variables".

How solid things break, and what the pieces of those things do when they break, is easily two semesters worth of study alone.

Here is MIT course 3.35 - Fracture and Fatigue
http://ocw.mit.edu/OcwWeb/Materials-Science-and-Engineering/3-35Fall2003/CourseHome/

It's all about "how stuff breaks". There is not a third year MIT course in "how stuff breaks" because it is some kind of simple question.

What you've repeatedly gotten in response to your question, from people with technical backgrounds is "no it is not a simple question". And forgetting even the mechanics of it - which is what you want - to the simpler question of the dynamics of it, is still not a simple question. Bazant's papers discuss some large scale dynamics of the problem, but you seem to think there is some "simple" way to take a large scale dynamic framework and reduce it to the mechanical results for a fractured piece of a complex structure during collapse.

No, you can't do that.

But what any engineer knows from the overall dynamics of the situation is that there is a tremendous amount of energy available, and there are lots of mechanisms to fling things outward during the collapse. But you got upset with me for simply stating the first thing that came to my mind to attempt an analogy with hitting a glass with a hammer - downward force and outward shattering.

Curiosity is a great thing. Getting angry with people because you do not recognize the oversimplification inherent in your question is inappropriate.

I was curious about physics too once, and I remain curious about a lot of things. One of the things I did to satisfy my curiosity about physics was to spend years of my life studying it. Among the things I learned was that the simplest of questions, and one of my favorites is:

"Why is copper reddish colored while other metals are silvery?"

...is a question to which the answer is devilishly complicated. That's a simple question that I used to know, but would take me at least an hour to get back up to speed on the Brillouin space energy diagram of copper electron momentum levels to even try to reduce to a simple answer.

You are not being curious. You are being a bully. Your question "opens the door" to your lack of understanding of the complexity of structures, and why structural engineers need large computer modeling capability to understand what is going on in order to simply make a building stand up - which is a LOT less complicated than what goes on when a building fails.

But anyway, I have no idea how cells divide, when they divide, or what makes them want to do it. I also have absolutely no knowledge whatsoever of French literature, and so I realize I'm not bloody likely to come up with a wizbang way for the Sorbonne to organize its library.