| 1 | So these are the only forces that act on this object. | |
| 2 | The only force holding them together is gravity. | |
| 3 | The most likely reason: a mysterious cosmic force known as dark energy. | |
| 4 | My current research is also investigating how tsunami forces change with distance from the shoreline. | |
| 5 | Lurking under the surface could be hidden worlds, complete with their own matter particles and forces. |