### VietTUG.org - old forum - threads' archive

thread_id = 923, contains 923, 924, 925, 926, 927, 939, 948, 949
id = 923, parent = 0, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.121, time = 2006/01/12 (1137054875) ,
subject = hyperbolic geometry, hits = 2321, karma = 0+0-,
Những liên kết về H.G:

Một vài hình ảnh...

Note: thuộc http://www.geom.uiuc.edu/ -- trung tâm tính toán và biểu diễn cấu trúc hình học. Trung tâm hiện đã đóng cửa, chỉ còn lại những điều đã cũ...

id = 924, parent = 923, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.121, time = 2006/01/12 (1137055663) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
Hyperbolic Geometry using Cabri

URL: http://mcs.open.ac.uk/tcl2/nonE/nonE.html

Nội dung: sử dụng Cabri biểu diễn đối tượng của H.G

id = 925, parent = 924, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.121, time = 2006/01/12 (1137055879) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
Why is it Important for Students to Study Hyperbolic Geometry?

URL: http://www.cs.unm.edu/~joel/NonEuclid/why.html

Nội dung: tại sao phả nghiên cứu HG? article không đề cập đến các ứng dụng,... -- trả lời cho câu hỏi đặt ra là tính độc lập của tiên đề 5 của hình học Euclid

id = 926, parent = 925, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.121, time = 2006/01/12 (1137056104) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
The Geometry of the Sphere

URL: http://math.rice.edu/~pcmi/sphere/
We are interested here in the geometry of an ordinary sphere. In plane geometry we study points, lines, triangles, polygons, etc. On the sphere we have points, but there are no straight lines --- at least not in the usual sense. However, straight lines in the plane are characterized by the fact that they are the shortest paths between points. The curves on the sphere with the same property are the great circles. Therefore it is natural to use great circles as replacements for lines. Then we can talk about triangles and polygons and other geometrical objects. In these notes we will do this, and at the same time we will continuously look back to the plane to compare the spherical results with the planar results.

We will study the incidence relations between great circles, the notion of angle on the sphere, and the areas of certain fundamental regions on the sphere, culminating with the area of spherical triangles. Our ultimate goal is two very nice results. First we will prove Girard's Theorem, which gives a formula for the sum of the angles in a spherical triangle. Then we will use Girard's Theorem to prove Euler's Theorem...

id = 927, parent = 926, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.121, time = 2006/01/12 (1137058249) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
Hyperbolic Geometry (1996)

Bản preprint, giới thiệu nhanh về HG.
These notes are intended as a relatively quick introduction to hyperbolic geometry. They review the wonderful history of non-Euclidean geometry. They give five different analytic models for and several combinatorial approximations to non-Euclidean geometry by means of which the reader can develop an intuition for the behavior of this geometry. They develop a number of the properties of this geometry which are particularly important in topology and group theory. They indicate some of the fundamental problems being approached by means of non-Euclidean geometry in topology and group theory.

id = 939, parent = 927, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.83, time = 2006/01/13 (1137162979) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
Thư viện hình

URL: http://math.harvard.edu/~ctm/gallery/index.html

( thư viện hình. có vài hình minh họa cho HG )

id = 948, parent = 939, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.83, time = 2006/01/14 (1137235860) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
Đủ thứ về HG, có lẽ là có ích:

URL: http://www.ics.uci.edu/~eppstein/junkyard/hyper.html

id = 949, parent = 948, thread = 923, catid = 26, locked = 0, moved = 0,
userid = kyanh, ip = 222.252.232.83, time = 2006/01/14 (1137235980) ,
subject = Re:hyperbolic geometry, hits = 0, karma = 0+0-,
Neutral and Non-Euclidean Geometries

URL: http://www.math.uncc.edu/~droyster/math … /hyprgeom/

Một Ebook book (HTML format). Giúp có cái nhìn tổng quan về Hình học. HG ghỉ là góc rất nhỏ trong cuốn sách này!