Zollner's Illusion
In this Illusion, the Vertical lines in the above figure are Parallel, but appear to be tilted at an angle.
See also Illusion
References
Jablan, S. ``Some Visual Illusions Occurring in Interrupted Systems.'' http://members.tripod.com/~modularity/interr.htm. Pappas, T. The Joy of Mathematics. San Carlos, CA: Wide World Publ./Tetra, p. 172, 1989.
- Univariate Polynomial
- Universal Graph
- Universal Statement
- Universal Turing Machine
- Unknot
- Unknotting Number
- Unless
- Unlesss
- Unmixed
- Unpoke Move
- Unsafe
- Unsolved Problem
- Unstable Improper Node
- Unstable Node
- Unstable Spiral Point
- Unstable Star
- Untouchable Number
- U-Number
- Upper Bound
- Upper Integral
- Upper Limit
- Upper Sum
- Upper-Trimmed Subsequence
- Upward Drawing
- Urchin