Description: Define surreal zero. This is the simplest cut of surreal number sets. Definition from Conway p. 17. (Contributed by Scott Fenton, 7-Aug-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-0s | |- 0s = ( (/) |s (/) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | c0s | |- 0s |
|
| 1 | c0 | |- (/) |
|
| 2 | cscut | |- |s |
|
| 3 | 1 1 2 | co | |- ( (/) |s (/) ) |
| 4 | 0 3 | wceq | |- 0s = ( (/) |s (/) ) |