Scientists say they believe they have captured the elusive Higgs Boson particle that gives matter mass.
Professor John Womersley, chief executive of the Science and Technology Facilities Council, told reporters at a London briefing that they had discovered a particle consistent with the Higgs Boson.
Discovery is the important word. That is confirmed. It's a momentous day for science.
There is a strong Welsh connection to the groundbreaking scientific project as Dr Lyn Evans from Aberdare was the project leader.
More top news
After the warmest Halloween on record, it's all about to go rapidly downhill!
An artist has created a tribute portrait of late presenter Lynda Bellingham made entirely from beef Oxo cubes.
A speed camera on a busy stretch of road in Swansea is catching 200 drivers a day - but so far none have been fined.