> [!infobox] <s class="aside-in"><em>mentioned in 6 topics</em></s> #### <s class="topic-title">[[dark energy]]</s> > [!wikipedia] [dark energy](https://en.wikipedia.org/wiki/Dark%20energy) > > In physical [[cosmology]] and [[astronomy]], dark energy is an unknown form of energy that affects the [[universe]] on the largest scales. The first observational evidence for its existence came from measurements of [[supernovae]], which showed an [[expanding universe]]. Understanding the universe's evolution requires knowledge of its starting conditions and composition. Before these observations, scientists thought that all forms of matter and energy in the universe would only cause the expansion to slow down over time. Measurements of the [[cosmic microwave background radiation]] (CMB) suggest the universe began in a hot Big Bang, from which [[general relativity]] explains its evolution and the subsequent large-scale motion. Without introducing a new form of [[energy]], there was no way to explain how scientists could measure an accelerating universe. ##### ^dataviews > [!dataview]+ Related unlinked notes > > No results to show for list query. > [!dataview]- Other unlinked mentions > > - [[Lambda-CDM model]] > - [[cosmological constant]] > - [[dark matter]] > - [[inflation theory]]