Greyship
A greyship is a spaceship which contains a region of density 1/2 (generally the stripes agar) that can be extended to an arbitrary size both horizontally and vertically.
The first greyships were found by Hartmut Holzwart and Jason Summers in 2005.[1][2][3] These ships traveled orthogonally at c/2. Since then greyships have been found for speeds c/3, c/4, c/5, and 2c/5.[4]
Types of greyships
Most known greyship components use the stripes agar and travel with-the-grain (parallel to the stripes); There are some known against-the-grain greyships, in which the stripes are perpendicular to the direction of travel; however, these are only known for a speed of c/2.[5]
Other than the stripes agar, there are a few known greyships that use the chicken wire agar[6], and some with other types of discontinuity.[7][8] A looser definition of greyship may also include ships with extensible, high-density agars of higher periods.
See also
References
- ↑ Dave Greene (July 9, 2005). "c/2 and 2c/4 "greyships"". Game of Life News. Retrieved on February 24, 2018.
- ↑ Dave Greene (September 6, 2005). "Greyship Update". Game of Life News. Retrieved on February 24, 2018.
- ↑ Dave Greene (December 10, 2005). "Holiday Greyships -- Grey No Longer!". Conway's Life: Work in Progress (weblog). Retrieved on February 24, 2018.
- ↑ Dave Greene (January 10,2011). "First c/5 greyship, and a new c/3". Game of Life News. Retrieved on February 24, 2018.
- ↑ Dave Greene (December 16, 2005). "New perpendicular greyships". Game of Life News. Retrieved on February 24, 2018.
- ↑ Dave Greene (April 3, 2006). "Chicken-Wire-Agar Greyships". Game of Life News. Retrieved on February 24, 2018.
- ↑ Dave Greene (December 16, 2005). "Hybrid greyships (perpendicular and parallel stripes)". Game of Life News. Retrieved on February 24, 2018.
- ↑ Dave Greene (December 18, 2005). "Fixed-Width and Slipping-Stripe Greyships". Game of Life News. Retrieved on February 24, 2018.
External links
- Greyship at the Life Lexicon