Albert Einstein's Theory of Relativity states that no object in the universe can travel faster than the speed of light in a vacuum. Scientists at CERN have recently measured particals that have exceeded that speed limit, even if by billionths of a second. They are now seeking scrutiny of their testing as confirmation could shake physics up a bit.
The teamhas published its workso other scientists can determine if the approach contains any mistakes.
If it does not, one of the pillars of modern science will come tumbling down.
Antonio Ereditato added "words of caution" to his Cern presentation because of the "potentially great impact on physics" of the result.
The speed of light is widely held to be the Universe's ultimate speed limit, and much of modern physics - as laid out in part by Albert Einstein in his theory of special relativity - depends on the idea that nothing can exceed it.
Thousands of experiments have been undertaken to measure it ever more precisely, and no result has ever spotted a particle breaking the limit.
"We tried to find all possible explanations for this," the report's author Antonio Ereditato ofthe Opera collaborationtold BBC News on Thursday evening.
"We wanted to find a mistake - trivial mistakes, more complicated mistakes, or nasty effects - and we didn't.