Tag

Dimension

All articles tagged with #dimension

Knots Fall Apart in Four-Dimensional Space, But Surfaces Remain Knotty
science18 hours ago

Knots Fall Apart in Four-Dimensional Space, But Surfaces Remain Knotty

The article explains that in four dimensions a knot tied on a rope cannot stay knotted, because the extra dimension lets strands slide past each other; by contrast, two-dimensional surfaces such as balloons can still be knotted in higher dimensions. A guiding formula says you can knot an object of dimension d only up to dimension 2d+1; for a rope (1D) that means up to 3D, while a 2D surface can be knotted in up to 5D. The piece uses analogies (ants on a line, a movie-like sequence of 3D frames) to visualize 4D space and notes that knotted surfaces in 4D is a vibrant area of research linking geometry to our understanding of four-dimensional space.

"Triangle Shrinkage: The Incredible Shrinking Shape"
mathematics2 years ago

"Triangle Shrinkage: The Incredible Shrinking Shape"

Mathematicians Alex Cohen, Cosmin Pohoata, and Dmitrii Zakharov have made a breakthrough in the Heilbronn triangle problem, a mathematical puzzle that has stumped researchers for decades. The problem involves finding the largest possible smallest triangle formed by three points within a square. The trio of mathematicians discovered a new upper bound for the size of the smallest triangle, using techniques from intersecting shapes, number theory, and Fourier analysis. Their findings have revitalized research on the problem and revealed new connections to other areas of mathematics.