Computer solves a major time travel problem
It is more than 120 years since H.G. Wells published The Time Machine, the novel that was to popularise the concept of time travel and lead to myriad stories on the theme. But it is only now that we have finally developed a plotline for time travel that makes logical sense – and it has been penned by a machine. Read more
Six physics equations that changed the course of history
Physics equations are forms of magic. They allow us to explain the past, such as why Halley’s comet visits every 76 years, and predict the future – as far as the ultimate fate of the Universe. Occasionally over the past few centuries, a new equation endowed the next generation with a new magical tool, and so changed the course of history. Here are some of the most pivotal. Read more
Five ways to travel through time
Travel into the past is probably impossible. Even if it were possible, Hawking and others have argued that you could never travel back before the moment your time machine was built. But travel to the future? That’s a different story. Science as we know it allows for several methods to take the fast-track into the future. Here’s a rundown. Read more
CERN finds four new X particles – how big a deal is this?
Physicists at CERN discovered four new “tetraquark” particles – unusual arrangements of four fundamental particles called quarks. The new particles are highly unstable, decaying almost immediately into other particles. These are not new fundamental particles heralding a new era of physics but rather are new combinations of previously known particles in the standard model of particle physics. Read more
Spinning galaxies question existence of dark matter
Some 80 years after dark matter was first theorised, we still have no idea what it is. Now, a study casts doubt on its existence altogether. According to the standard model of cosmology, the immense gravity of dark matter is crucial for explaining why galaxies can spin so fast without tearing themselves apart. Read more
Particle physics: a primer to the theory of (almost) everything
The Standard Model categorises all of the particles of nature, in the same way that the periodic table categorises the elements. The theory is called the Standard Model because it is so successful it has become “standard”. There are still a few kinks to be ironed out (as well as a couple of whopping omissions). That’s why it is sometimes called the “Theory of Almost Everything”. Read more
Quantum physics for the terminally confused
Does quantum physics melt your brain? First, don’t panic. You’re not alone in your confuddlement. As legendary physicist Richard Feynman said: “I think I can safely say that nobody understands quantum mechanics.” Nevertheless, quantum theory is vital for describing how our world is screwed together. So we’ve broken down the ideas of quantum theory to the level where even a five-(or 55) year-old can get the gist. Read more
The dark side of the universe – a primer
Over the past 40 years astronomers have realised that everything we can see – all the stars, planets and galaxies – make up less than 5% of the entire universe. What is the rest? The short answer is, we have no idea. What we do know is there are two gaping holes in our understanding of our universe. As a placeholder, physicists call them dark matter and dark energy. Read more
Glimpses of the Madala boson: have we detected the dark Higgs?
Using the same data used to discover the Higgs boson in 2012, physicists from South Africa, India and Sweden claimed to see evidence of its dark matter counterpart – a new particle the team dubbed the Madala boson. If true, this could be groundbreaking – the long-sought-after connection between particle physics and dark matter, the mysterious ‘stuff’ that makes up around 85% of matter in the universe. Read more
Topology explained – and why you’re a donut
You are a donut. It boils down to topology, or the maths of shapeshifting, stretching and pulling, but not tearing. It makes strange connections between apparently unrelated objects, such as you and the donut. It also explains exotic quantum behaviour in superfluids and superconductors. And it’s leading to strange new kinds of materials which scientists never thought possible. Read more