Volume XXI

VOL XXI

Geombinatorics Quarterly

July 2011 (Volume XXI, Issue 1)

Editors Page   4
New Essays    
The Best Polynomial Bounds for the Number of triangles in a Simple Arrangement of n Psuedo-Lines By Jérémy Blanc 5
Representations of Spatial Variation: Geometric Approach and Environmental Applications By Micha Kosheleva, Octavio Lerma, and Craig Tweedie  
Fast Recognition of Planar Non-Unit Distance Graphs By Sascha Kurz 6
Book Reviews    
“Because Germany Needs Me,” A Review of David C. Cassidy’s book Beyond Unvertainty: Heisenber, Quantum Physics, and the Bom By Alexander Soifer 34
Recent Books   37
Subscription Form   39

July 2011 (Volume XXI, Issue 2)

Editors Page   44
New Essays    
A Geometric Extermal Result for Cubi Arrays By James Gossel and Peter Johnson 45
Side-Angle Reciprocity- A Survey By Branko Grünbaum 55
A Lower Bound for 4-Regular Planar Unit Distance Graphs By Sascha Kurz 63
Packing Constrained Point Coverings By Velt Elser 73
Recent Books   81
Subscription Form   83

January 2012 (Volume XXI, Issue 3)

Editors Page   88
New Essays    
Inversion of the “midpoints polygon” construction By Branko Grünbaum 89
A Convex Polygon with Small Sum of Squared Distances Between its Vertices By Janusz Januszewski 97
On Topological Diversity of Unbounded Convex Bodies in the Hyperbolic Space By Alexander Kuz’minykh 101
Chromatic numbers of two-distance graphs in Q2 By Matt Noble 110
A lovely bunch of coconuts By John E. Wetzel 117
Recent Books   122
Subscription Form   123

April 2012 (Volume XXI, Issue 4)

Editors Page   128
New Essays    
On the Cyclic Van Der Waerden Numbers By Daniel Grier 129
More on the Second Babai Number and Second Clique Number of Q3 By Matt Noble 132
Van der Waerden and Heisenberg:
The Story of One Friendship in Seventeen Sketches		 By Alexander Soifer 138
Tangles Thrackes By János Pach, Radös Radoičić and Gézá Tóth 157
Recent Books   170
Subscription Form   171