337 articles from WEDNESDAY 5.5.2021

Long-term monitoring shows successful restoration of mining-polluted streams

Many miles of streams and rivers are polluted by toxic metals in acidic runoff draining from abandoned mining sites, and major investments have been made to clean up acid mine drainage at some sites. A new study based on long-term monitoring data from four sites in the western United States shows that cleanup efforts can allow affected streams to recover to near natural conditions within 10 to 15...

Swarm of photons can somersault in lockstep

Scientists demonstrate the surprising result that photons in vacuum can have orbital angular momentum (OAM) vectors pointing sideways, at 90 degrees to the direction of propagation - a result literally orthogonal to the decades-long expectation that OAM vectors could only point forward or backward.

Yes, you can have more than 150 friends: New study deconstructs Dunbar's number

An individual human can maintain stable social relationships with about 150 people. This is the proposition known as "Dunbar's number"—that the architecture of the human brain sets an upper limit on our social lives. A new study from Stockholm University indicates that a cognitive limit on human group sizes cannot be derived in this manner.

HS2 workers to exhume 3,000 bodies in Buckinghamshire churchyard

Archaeologists say findings at Old St Mary’s church in Stoke Mandeville will shed light on life dating back to Norman timesHS2 contractors are planning to disinter 3,000 bodies discovered in a churchyard in Buckinghamshire that lies in the path of the new high-speed rail link.Archaeologists excavating a site at Old St Mary’s church in Stoke Mandeville, Buckinghamshire, which was built shortly...