Uncertainty ironically is one thing you can be certain of in quantum mechanics and the first attempt to quantify this is the Heisenberg Uncertainty Principle. At the time that theory was developed though, an assumption was made which later has revised away by Heisenberg and others. Now researchers at the University of Toronto, as reported by the Optical Society of America, have proven that the original principle was indeed incorrect.
When the principle was first developed, Heisenberg stated that the uncertainty of a measurement is the result of making a measurement. Eventually this interpretation was changed as indeed uncertainty is an intrinsic property of quantum mechanical systems. What the University of Toronto researchers did is prove this by making small measurements of photons that were more accurate than the original uncertainty principle allowed. While measurement can still disturb a quantum system, gentle measurements do not disturb the system as much, and repeated gentle measurements can get the information you are after.
While demonstrating that an already outdated principle is indeed incorrect may not seem important, all research concerning precision measurements like those in this study are important. Such measurements are needed for future technologies such as quantum computers.