How to manage this template's collapsible groups/sections option
This template includes collapsible groups/sections. When it first appears, one of these groups/sections may be set to be visible ("expanded") while the others remain hidden ("collapsed") apart from their titlebars. To achieve this, include the parameter|name where name is one of the following words that identify the groups/sections (omit any speech or quotation marks):
fundamentals
phenomena
equations
solutions
spacetime
scientists
For example: {{General relativity sidebar/doc |phenomena}}