California scientists have achieved a major advance in fusion energy, a technology that could potentially provide clean, carbon-free power in years to come, the Department of Energy announced Tuesday. The work uses giant lasers to create heat and pressure close to that found in the sun, enough to drive atoms together, releasing tremendous energy.   The hope is that in time, this process can be scaled up and done cheaply enough to create power that is carbon-free without the creation of radioactive waste that is the challenge with fusion's more problematic sibling, nuclear fission. "It's a scientific milestone," said Arati Prabhakar, director of the White House Office of Science and Technology Policy. "It's also an engineering marvel beyond belief." Click the link in our bio to learn more about the breakthrough.