![Scientific American Magazine Vol 324 Issue 2](https://static.scientificamerican.com/sciam/cache/file/F8501A13-75B7-496C-83A2DE64F356A6DB_source.jpg?w=300)
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Features
The Cosmological Constant Is Physics' Most Embarrassing Problem
Physicists have new ideas about why the energy of empty space is so much weaker than it is predicted to be
Now Is the Time to Reestablish Reality
We need to agree on the evidence—so we can disagree on what to do in light of it
The Epic, Absurdly Complex Battle between a Zombie Maker and Its Victim
The emerald jewel wasp is a cockroach’s worst nightmare
Hormone Levels Are Being Used to Discriminate against Female Athletes
Despite slim evidence, testosterone is keeping some women off the field
To Control COVID, Biden Needs to Marshal Federal Resources--and Change Attitudes
The incoming U.S. president must help skeptics see benefits in masks and persuade Congress to spend more money on testing and protective gear
Biden Should Restore the Role of Science in the U.S. Government
Four ways the new administration can elevate evidence and build up the science ranks
On Climate, Biden Must Do More Than Undo Trump's Damage
The new administration cannot just go back to the future on carbon emissions
Mysteries of COVID Smell Loss Finally Yield Some Answers
Explanations begin to arise at the molecular level for this vexing but commonplace symptom
Climate Change Hits Rock and Roll as Prized Guitar Wood Shortage Looms
Flooding and a wood-boring beetle threaten supplies of storied “swamp ash”
An Underappreciated Danger of the New Space Age: Global Air Pollution
As private launches increase dramatically, so will emissions of CO2, particulates and other noxious substances