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.
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The Smith Commission is expected to set out new powers for the Scottish Parliament that could lead to major change for Wales
Remaining largely cloudy through the day with some intermittent drizzle likely in the east
Close interest is being paid in Wales to the recommendations of the Smith Commission for future devolution to Scotland