‘Cold Spot’ in the CMB. tagged posts

An illustration of a nitrogen-doped graphene quantum dot like those being tested at Rice University for use as catalysts to reduce carbon dioxide, a greenhouse gas, into valuable hydrocarbons. Courtesy of the Ajayan Group

Graphene quantum dots may offer a simple way to recycle waste CO2 into valuable fuel rather than release it into the atmosphere or bury it underground, according to Rice University scientists. Nitrogen-doped graphene quantum dots (NGQDs) are an efficient electrocatalyst to make complex hydrocarbons from carbon dioxide, according to the research team led by Rice materials scientist Pulickel Ajayan. Using electrocatalysis, his lab has demonstrated the conversion of the greenhouse gas into small batches of ethylene and ethanol.

NGQDs worked nearly as efficiently as copper, w...

The cosmic microwave background over the whole sky, with the unusual ‘Cold Spot’ feature circled at the lower right. Credit: Image courtesy of University of Portsmouth

The map of cosmic void positions – large empty spaces with relatively few galaxies – and superclusters – huge regions with many more galaxies than normal – can be used to measure the effect of dark energy ‘stretching’ the universe. The results confirm the predictions of Einstein’s theory of gravity. Lead author Dr Seshadri Nadathur from the University’s Institute of Cosmology and Gravitation said: “We used a new technique to make a very precise measurement of the effect that these structures have on photons from the cosmic microwave background (CMB) – light left over from shortly after the Big Bang – passing through them...