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Soflasnapper
01-16-2010, 05:01 PM
I've bought some pool books from Amazon, so they e-mail me with suggestions to buy new books in that category from time to time.

This new one they suggest makes my head hurt just reading the title and description, even though I have a degree in mathematics.

Dynamical Billiards: Dynamical System, Specular Reflection, Speed, Hamiltonian Mechanics, Cue Sports, Non-Euclidean Geometry, Surface, Curvature, Outer ... Riemannian Manifold, Reflection (Physics) (Paperback)

Editorial Reviews
Product Description
High Quality Content by WIKIPEDIA articles! A billiard is a dynamical system in which a particle alternates between motion in a straight line and specular reflections from a boundary. When the particle hits the boundary it reflects from it without loss of speed. Billiard dynamical systems are Hamiltonian idealizations of the game of billiards, but where the region contained by the boundary can have shapes other than rectangular and even be multidimensional. Dynamical billiards may also be studied on non-Euclidean geometries; indeed, the very first studies of billiards established their ergodic motion on surfaces of constant negative curvature. A three-dimensional analogue of such a surface is the holly leaf. The study of billiards which are kept out of a region, rather than being kept in a region, is known as outer billiard theory.The motion of the particle in the billiard is a straight line, with constant energy, between reflections with the boundary (a geodesic if the Riemannian metric of the billiard table is not flat). All reflections are specular: the angle of incidence just before the collision is equal to the angle of reflection just after the collision.
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Whew! Sounds like they're talking about playing on odd-shaped tables, lol! (Plus angle of incidence does NOT equal angle of reflection in real life, except under certain conditions, right?)

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Soflasnapper
01-17-2010, 07:41 PM
The purchase at Amazon that made me think I'd want this book was 'Banking with the Beard'!

I think their suggestion engine needs a little work.

dr_dave
01-17-2010, 10:53 PM
To be honest, it makes my head hurt too ... not exactly leisurely reading (and probably not very useful to pool players ... even those interested in the detailed physics of the game). Physicists sometimes use the word "billiards" to mean something a little different from what we mean.

Regards,
Dave

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Soflasnapper</div><div class="ubbcode-body">I've bought some pool books from Amazon, so they e-mail me with suggestions to buy new books in that category from time to time.

This new one they suggest makes my head hurt just reading the title and description, even though I have a degree in mathematics.

Dynamical Billiards: Dynamical System, Specular Reflection, Speed, Hamiltonian Mechanics, Cue Sports, Non-Euclidean Geometry, Surface, Curvature, Outer ... Riemannian Manifold, Reflection (Physics) (Paperback)

Editorial Reviews
Product Description
High Quality Content by WIKIPEDIA articles! A billiard is a dynamical system in which a particle alternates between motion in a straight line and specular reflections from a boundary. When the particle hits the boundary it reflects from it without loss of speed. Billiard dynamical systems are Hamiltonian idealizations of the game of billiards, but where the region contained by the boundary can have shapes other than rectangular and even be multidimensional. Dynamical billiards may also be studied on non-Euclidean geometries; indeed, the very first studies of billiards established their ergodic motion on surfaces of constant negative curvature. A three-dimensional analogue of such a surface is the holly leaf. The study of billiards which are kept out of a region, rather than being kept in a region, is known as outer billiard theory.The motion of the particle in the billiard is a straight line, with constant energy, between reflections with the boundary (a geodesic if the Riemannian metric of the billiard table is not flat). All reflections are specular: the angle of incidence just before the collision is equal to the angle of reflection just after the collision.
------------

Whew! Sounds like they're talking about playing on odd-shaped tables, lol! (Plus angle of incidence does NOT equal angle of reflection in real life, except under certain conditions, right?)

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</div></div>

dr_dave
01-17-2010, 10:54 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Soflasnapper</div><div class="ubbcode-body">The purchase at Amazon that made me think I'd want this book was 'Banking with the Beard'!

I think their suggestion engine needs a little work. </div></div>Well stated!

bradb
01-18-2010, 12:56 PM
It appears to me its trying to say that if you hit a ball it will go straight then slow down.

I think they are on to something here.