articles

Using an atomic quantum simulator, scientists at the University of Illinois at Urbana-Champaign have achieved the first-ever direct observation of chiral currents in the model topological insulator, the 2-D integer quantum Hall system.

Topological Insulators (TIs) are arguably the most promising class of materials discovered in recent years, with many potential applications theorized. That’s because TIs exhibit a special quality: the surface of the material conducts electricity, while the bulk acts as an insulator. Over the last decade, scientists have extensively probed the microscopic properties of TIs, to better understand the fundamental physics that govern their peculiar behavior.

In the first ecosystem-wide study of changing sea depths at five large coral reef tracts in Florida, the Caribbean and Hawai’i, U.S. Geological Survey researchers found the sea floor is eroding in all five places, and the reefs cannot keep pace with sea level rise. As a result, coastal communities protected by the reefs are facing increased risks from storms, waves and erosion.

The unpredictable annual flow of the Nile River is legendary, as evidenced by the story of Joseph and the Pharaoh, whose dream foretold seven years of abundance followed by seven years of famine in a land whose agriculture was, and still is, utterly dependent on that flow. Now, researchers at MIT have found that climate change may drastically increase the variability in Nile’s annual output.

A trace gas present in the atmosphere in miniscule amounts is helping scientists answer one of the biggest questions out there: Has plant growth increased alongside rising levels of carbon dioxide in the atmosphere?

Con una simple orden ejecutiva emitida a finales de marzo, la administración Trump lanzó un sólido esfuerzo para revertir las políticas climáticas de la era Obama diseñadas para reducir las emisiones de dióxido de carbono (CO2) en los Estados Unidos. La principal de estas políticas es el Plan de Energía Limpia, que se dirige a las centrales eléctricas de carbón y gas natural que representan alrededor del 40 por ciento de las emisiones de CO2 del país.