For centuries, the field of archaeology has depended on what's visible to the naked eye. Now, researchers are revealing what lies beneath the surface of a key evolutionary fossil, Darwin's "dinobird."
The Big Bang created an equal number of particles and antiparticles. But we don't ever come into contact with antiparticles, and scientists don’t see any out there in the universe. What happened to all the antimatter? In a way, antimatter is the flip side of matter. Each subatomic particle has an antiparticle with the same mass but the opposite charge.
The Big Bang created an equal number of particles and antiparticles. But we don't ever come into contact with antiparticles, and scientists don’t see any out there in the universe. What happened to all the antimatter? In a way, antimatter is the flip side of matter. Each subatomic particle has an antiparticle with the same mass but the opposite charge.
What if it were possible to build a particle accelerator to explore energies beyond even that of the proposed 30 kilometer International Linear Collider - at a fraction of the size, power consumption and cost? SLAC physicists are studying new accelerator technology, called plasma wakefield acceleration, that could make it possible.
SLAC's two major X-ray user facilities support a variety of protein folding studies with applications in medicine, environmental, ecological and basic life sciences.
Water, by any measure, is strange stuff. It behaves unlike any other liquid. It has a tremendous capacity for carrying heat—which is how the Gulf Stream keeps Europe warm. Water's solid phase—ice—is less dense than the liquid, which is why ice floats; life on Earth as we know it could never have formed if oceans and lakes froze from the bottom up. Water also has unusually strong surface tension—a property essential for the capillary action at work in the roots of plants and within our cells. These strange properties are what make water such an essential substance to the existence of life.
Hydrogen - the most plentiful element in the universe - could play a role in meeting the world's demand for energy while reducing our dependence on carbon-based fuels. Although hydrogen has piqued the interest of researchers as a clean, renewable energy resource, a number of major obstacles remain before a system for producing and using hydrogen can supplant fossil fuel usage in a meaningful way.
Arsenic contamination of underground water supplies is a major problem around the world. Studies of how different forms of arsenic deposit in the ground at different depths and move through the water system are helping prevent arsenic poisoning, especially in developing nations like Bangladesh.