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A gooey substance normally wouldn’t seem like it could stop a bullet, but an Air Force Academy cadet has created just that. Air Force Academy Cadet 1st Class Hayley Weir created a goo-like substance that can stop bullets. Cadet 1st Class Hayley Weir’s interest in bullet-stopping materials was piqued when she took a chemistry class at the academy in 2014. The class was given three materials to combine in a way that could stop a bullet. “Up to that point, it was the coolest thing I’d done as a cadet,” Weir, a senior at the academy, told Air Force Times....

Container's material properties affect the viscosity of water at the nanoscale Sep 19, 2013 Enlarge Georgia Tech associate professor Elisa Riedo poses with a glass water bottle and a plastic water bottle. While container materials don't significantly affect the rate at which water pours from bottles of this size, a new study shows that the properties of containers at the nanoscale dramatically affect the viscosity of water. Credit: Rob Felt Water pours into a cup at about the same rate regardless of whether the water bottle is made of glass or plastic. But at nanometer-size scales for water and potentially...

Perfect liquids suggest theory’s math mirrors something real Shadows live in a simple world. They glide effortlessly across any sort of surface, oblivious to the higher dimension of space in which 3-D bodies move, collide and sometimes block the paths of rays of light. Shadows have no idea how important that third dimension is, and how objects in it endow those very shadows with their quasi-physical existence. Indeed, the laws of shadow physics all depend on the third dimension’s presence. And just as the clueless inhabitants of the shadow world require an extra dimension to explain how they exist and...

Black holes may define the perfect fluid, suggests a study of black holes that only exist in a theoretical 10-dimensional space. The finding may have spawned a new universal law in physics, which puts constraints on the way fluids behave in the real world. Dam Thanh Son from the University of Washington, US, and his colleagues used string theory to model a 10-dimensional black hole as a liquid. String theory tries to explain fundamental properties of the universe by predicting that seven more spatial dimensions exist on top of the known three. While the concept is currently unproven as a...