From the hunt for dark matter to quantum time travel, plus 100 years of Einstein, here are the Cosmos editors’ favourite physical science stories of the year.
Number 10:
Einstein’s gravitational waves remain elusive
The cosmic do-si-do of two supermassive black holes spiralling towards each other is a cataclysmic dance of such intensity, it should ripple the fabric of spacetime itself – or so says Einstein’s general theory of relativity. One hundred years have passed since Einstein first proposed the existence of gravitational waves, but they are yet to be detected directly. Read more
Number 9:
A better explanation for why sodium explodes in water
There’s nothing like an explosion to help you learn chemistry. Remember when your high school teacher dropped a lump of sodium into water? Bang! Lesson learnt: sodium is highly reactive. But it turns out there’s more to that lesson. Read more
Number 8:
Creating a blacker black
Black just got a whole lot darker. Researchers from Saudi Arabia’s King Abdullah University of Science and Technology created a material that absorbs up to 99% of visible and infrared light. And it was inspired by a bright white beetle. Read more
Number 7:
Atoms in close-up
“Nothing exists except atoms and empty space.” – Democritus 460-370 BC. Perhaps it was the whiff of baking bread that led Democritus to imagine that matter was composed of tiny, indivisible building blocks. Atoms, he called them, meaning something that cannot be cut. If only the Greek philosopher could take a peek through today’s scanning transmission electron microscopes. Read more
Number 6:
Ghost traps: the hunt for dark matter
If you were designing a villain’s lair for a James Bond movie, you would be hard pushed to create one as spectacular as Italy’s subterranean Gran Sasso Laboratory. Hidden beneath a mountain, Gran Sasso physicists are hunting for dark matter. This elusive material makes up 85% of the matter in the Universe. We know it must be out there – without it galaxies would fly apart and we would not exist. Are we finally closing in on dark matter? Read more
Number 5:
Enter the graphene era
True or false? It’s possible to make a sheet of carbon that is a single atom thick. If you’d asked that question before 2004, most scientists would have laughed you out of the room. With the introduction of graphene in 2004, two-dimensional carbon is not only possible, it is promising to usher in a new industrial age. Read more
Number 4:
New model of the cosmos: a Universe that begins again
The failure so far to find gravitational waves has some cosmologists wondering if the ‘inflationary’ theory of the Big Bang is right – or whether the Universe actually behaves quite differently to that. Read more
Number 3:
Time travel and the single atom
We all have times we wish we could go back in time and make a different decision. Now that appears to be possible – for single atoms, at least. Physicists have confirmed one of the most profound thought experiments of quantum physics. It appears to show that present actions can affect past events. Read more
Number 2:
Shape-shifting neutrinos that led to a Nobel Prize
Every second, thousands of billions of high-energy particles called neutrinos fly through your body at close to the speed of light. Fortunately, they’re harmless – although distinctly strange. The 2015 Nobel prize in physics was awarded to two scientists who discovered neutrinos continually shape-shift as they move through space. Read more
Number 1:
General Relativity – still ahead of its time
A century ago Einstein sweated blood to give us his mind-bending theory of gravity. As technology caught up, his predictions were verified, one by one. Now only gravitational waves remain. Read more