
Structure and Interpretation of Classical Mechanics - octatoan
http://groups.csail.mit.edu/mac/users/gjs/6946/sicm-html/book.html
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pckspcks
I found this one of the most useful books I've read, but less so for the
physics (which was mostly an intellectual curiosity), and more so for
understanding how to write good code.

In it, Sussman shows you how to:

* Write a Lagrangian

* Symbolically convert it into Lagrange's Equations

* Compile those into native code

* Numerically integrate the with an optimized numerical algorithm to get a path of motion.

And all of this, with beautiful, clean, concise, simple code.

A-fing-mazing.

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sasvari
previous submissions with discussions:

[https://news.ycombinator.com/item?id=6947257](https://news.ycombinator.com/item?id=6947257)

[https://news.ycombinator.com/item?id=1581696](https://news.ycombinator.com/item?id=1581696)

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cmrx64
I love love _love_ this book. Its explanations are wonderful and for someone
deeply entrenched in CS like me it is a great approach to learning modern
classical mechanics.

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agumonkey
I've read somewhere that the Lagrangian approach was too computationally
intensive; leading to explosion of possible paths and dimensions. Anyone can
confirm ?

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ble
Too computationally intensive for what?

The Lagrangian approach is kinda great. If you can describe the potential
energy and the kinetic energy of a system as two functions of whatever
variables, Lagrangian mechanics allows you to derive the differential
equations that govern the evolution of that system for free.

There's absolutely zero fucking around with forces, torques, etc. to get
yourself a set of equations with which to model system behavior. You do have
to add one constraint equation for every constraint on the system, but this is
way easier than trying to formulate a set of differential equations that just
happens to satisfy an arbitrary set of constraints.

I don't know of a reason why Lagrangian mechanics would tie one to a
particular algorithm or class of algorithm; pretty much no matter how you do
it, if you're modeling a mechanical system, you're solving some differential
equations in one way or another.

TL:DR; can't confirm at this time

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SilasX
But doesn't it have a hard time with coulomb friction, since you can only work
with conservative fields/forces? A quick search confirms you have to use a
bolted-on "dissipation function".

~~~
pckspcks
Correct. In contrast to Newtonian mechanics, Lagrangians and Hamiltonians
completely describe essentially all fundamental laws of physics -- including
things like quantum and relativity.

However, they are cumbersome to work with for some complex, compound
phenomena, such as friction.

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MaxScheiber
Is there a solutions manual available for this book? I couldn't find any
mention of one on the MIT Press website, and a quick Google search wasn't
helpful.

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userbinator
It looks like the result of combining the first volume of
[http://en.wikipedia.org/wiki/Course_of_Theoretical_Physics](http://en.wikipedia.org/wiki/Course_of_Theoretical_Physics)
with SICP.

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rr56
Is anybody familiar with any Scheme notebooks preferably with math.js or
something similar?

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PaulHoule
Frankly I find it uninteresting because it doesn't talk much about chaos,
which is the normal condition of classical mechanics. You certainly can model
aspects of resonance with classical perturbation theory, but the most
remarkable think about classical perturbation theory is that it doesn't work
very well.

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pckspcks
Yes it does. I'm confused why you believe it doesn't....

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aswanson
Any pdf downloadable version?

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bitsofpancake
Link on Wikipedia:
[https://drive.google.com/file/d/0BxVCLS4f8Sg5MDIzMzJmZDQtZGE...](https://drive.google.com/file/d/0BxVCLS4f8Sg5MDIzMzJmZDQtZGEzMS00NjgxLWE0MjYtMmNlMDA5ZGNmMjg2/view)

