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# Simulating Reality

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A lot of events and phenomena can be simulated. With every passing year, not only does the universe of things that can be successfully subjected to simulation grow, but the degree of the endeavor and thus the accuracy of the results improves.

Let's use a dice as an example. The simplest simulation would be a one-liner program:

```Result = rnd(6);
```

This assumes a perfect dice, which is not always the case. Read on...

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Anecdote:
When I was a child in a carnival back home, there was a "magician" with a table and some dice. After reading the rules posted behind him, I was sure that there was a way I could easily win. Soon, the fool in me was separated from his money. So, I decided to stick around and observe the M.O. of the enterprising guy closely. Sometimes, he would insert his hand inside his pocket and retrieve another pair of dice. These ones were a tiny bit flattened. You could see that the black dots that formed the numbers 3 and 4 were smaller (you probably know that the opposite sides of a dice always add up to 7, correct?)
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Just to make the problem a thousand times harder, consider:

- the difference in weight of the 6 faces.

and a million times even harder

- the effect of aerodynamics in those carved tiny holes as the dice spins around in mid-air and bounces off the table.

For the impatient: With the advancements in science and technology, it turns out that simulating the fatal shot that hit president Kennedy -and thus discovering the precise trajectory of the projectile- is indeed a lot harder than my one-liner computer program above, but A LOT easier than the last dice simulation.

https://en.wikipedia.org/wiki/Simulated_reality

Edited by Ramon F. Herrera
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After high school, I worked several years for a baseball team in Venezuela ("Cardenales de Lara"). They had just purchased an electronic scoreboard (made in Venezuela, believe it or not, part of a Master's Thesis) and being the geeky type, I was appointed the operator. I was in charge not of the scores, but of the part that had rotating text:

"Do as Fred Manrique! Deposit your savings in Banco de Lara"

or otherwise made fun of the opposite team. At the heart of the system there was an Intel 8080. There was no floppy or anything (way too expensive) so I had to keep on retyping everything in the inter-innings.

During run-scoring rallies, using the industrial grade (to put it mildly) loudspeakers, we played a song that drove the visiting team nuts. A few years later, a friend of mine, member of the team's board was at the Toronto Blue Jays stadium, when one of the American players (Lloyd Moseby) recognized his face but could not remember my friend's name, pointed at him and started dancing and singing the catchy melody. Roy told me:

"Ramon, you are not going to believe this! People are singing your song in Canada!"

Of course, the William Tell Overture (aka, the Lone Ranger theme) was also played often. Well, as often as we were winning...

Long story short: I got hooked on computers, could not decide whether I preferred the hardware or the software better -as a major- ended up in the US.

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Anecdote:
It was quite coincidental. I met Fred at a time when sometimes he did not have enough money for cab fare, and my brother (motorcycle courier for the baseball team) drove him to a humble apartment, shared with a couple of teenage-ish baseball prospects. Little did we know that several years later, Manrique would be in the Big Leagues and I would be in the same city as him. First, he played for the St. Louis Cardinals: I was studying there and then he played for the Boston Red Sox while I lived in Cambridge. I kept on bumping into him at the Miami Airport AND he happened to buy an apartment back home, in the tower next to the one where my mom lives. Everybody recognized him because his was the only red (as in cardinal), convertible Mercedes in the city.
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In college I took a class titled "Computer Aided Analysis and Design of Electronic Circuits". Much to my amazement and delight, here in the US, if there is a topic that you particularly like, and there is no course that quite covers it, you may create your own course! That is a far cry from the dictatorial Latin American universities. The novelty of the software that I wrote was that instead of typing the components of the circuit ("R1", "Cshunt", "L35"), the user picked and dropped them. That is the natural way for electrical engineers to study circuits: drawing them. The Mac had just been invented (1985). I knocked off the Macintosh (Mac Paint) interface, with a palette that provided wires, capacitors, inductors, resistors, etc. To my discharge and before I am accused of plagiarism, my offense was seldom unique: Adobe stole the same idea for Photoshop, Illustrator, etc.

At this point you are probably wondering:

"What does all this have to do with the price of tea in China!!??"

Well taken. Recall the dice simulation? How reality can be simulated at many levels? A professor used to tell us:

"We are using values that facilitate the computations. Instead of a capacitance of 50 microFarads, we use 50 farads because the circuit only exists on a black board and your notebooks. If you young people can actually find a 50 Farad capacitor, it can probably lift a ship from the sea water".

Well, after a couple decades, I decided to take a close look at the state of the art in simulation. My jaw dropped when I saw advances such as the ones below:

Edited by Ramon F. Herrera
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Hey Ramon,

I became interested in computers (and later it became my career) in the Army. I had taken a computer course in high school and had learned a tiny bit about computers punching holes in cards and stacking them in a loader so that the computer could read what I wrote. Around the the same time, I was introduced to my first simulator, one of my best friend's grandfather had invented the LINC trainer for training pilots in WW2 and the friend had a working model with it's command desk in his basement! We spent hours drinking beer and simulating bombing runs on all kinds of locations long before that activity would be considered politically incorrect. Later in 1984, in Germany, two little green trailers appeared on my base. These were prototypes of the US Army's first tank simulators. It was very expensive to gas up an M1 tank and take it out to the range, the simulators, based now on a computer generated graphics engine were designed to alleviate that cost. My earlier exposure to simulators, albeit analog not computer based simulators, gave me an edge and I quickly became one of the most proficient gunners. I also became proficient in the cabling, setup and troubleshooting of the systems. This eventually led to my career in MIS (now IT) in Operations as a Systems Analyst.

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Hey Ramon,

I became interested in computers (and later it became my career) in the Army [...]

Chris,

I was amazed when you mentioned a Bell modem. I thought I was old-timer! My first one (bought with the computer, the very first IBM PC sold in the state of Iowa and likely one of the first ones in Venezuela) was a Hayes Smartmodem, invented by Dennis Hayes. It ran at the glorious speed of 300 baud. In the Christmas break, I took the computer back home. The customs person in the Caracas airport asked me to open the container (a box of wood with a handle, covered by make believe "leather", advertised in the new, very thin, stapled magazine "PC World"):

Customs agent: "What is that?"

Ramon: "A personal computer"

Customs agent: (scratches his head, puzzled, impatient) .... "Just move on..."

Since I had no other modem to connect to (international phone calls were extremely expensive at the time - Later while at MIT I dialed extensively, long calls from Barquisimeto to Cambridge) my younger brothers had fun taking the other telephone extension, chirping and making all kinds of unnatural noises while I had a communications software running (*). The modem placed random characters on the screen. That is impossible today, with the modern modulation (quadrature, trellis) schemes.

I had a queue of neighbors, relatives, visitors, wanting to see the novelty. I sold it to one of them.

(*) A terminal emulator which IBM included for free, with source code, written in BASIC.

Edited by Ramon F. Herrera
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My first one (bought with the computer, the very first IBM PC sold in the state of Iowa and likely one of the first ones in Venezuela) was a Hayes Smartmodem, invented by Dennis Hayes. It ran at the glorious speed of 300 baud.

I got my first Hayes Modem at Radio Shack. It was a modem/phone, a push button phone with 300 baud modem built in. It was a very good clear phone and I used it as such for years after upgrading my modems. I don't have my first computer, it was a shamefully horrible Coleco Adam (cassette drive, built in printer for output and no display). I do have the next one I bought, for a small fortune at the time, an Apple 512ke that's still in my closet, packed in it's original box. My wife wanted to kill me for that.

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After a couple decades, I decided to take a close look at the state of the art in simulation. My jaw dropped when I saw advances such as the ones below:

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Abstract

For the structure mechanics of human body, it is almost impossible to conduct mechanical experiments. Then the finite element model to simulate mechanical experiments has become an effective tool. By introducing several common methods for constructing a 3D model of cranial cavity, this paper carries out systematically the research on the influence law of cranial cavity deformation. By introducing the new concepts and theory to develop the 3D cranial cavity model with the finite-element method, the cranial cavity deformation process with the changing ICP can be made the proper description and reasonable explanation. It can provide reference for getting cranium biomechanical model quickly and efficiently and lay the foundation for further biomechanical experiments and clinical applications.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3576802/ (Cool images! Hover the mouse over Figure 1, etc )

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Edited by Ramon F. Herrera
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After a couple decades, I decided to take a close look at the state of the art in simulation. My jaw dropped when I saw advances such as the ones below:

See this nice guy:

Check out the cool things that he and his team are working on:

Finite element simulation of bullet impacting skull (1/2)

Finite element simulation of bullet impacting skull (2/2)

Notice the 2nd. YouTube video, Comments Section. You can see how I posted a note (in Spanish) inviting Alejandro to participate in the JFK case. He politely declined. :-(

-Ramon

Edited by Ramon F. Herrera