From returning to the Moon to establishing outposts on Mars, NASA has the need for more power than ever before. Could nuclear fission be the solution they’ve been searching for?
Watch more Focal Point! | https://bit.ly/2J9b9LC
Continue reading “NASA’s New Space Engine Is Powered by Nuclear Fission” »
About 80% of all the matter in the cosmos is of a form completely unknown to current physics. We call it dark matter, because as best we can tell it’s…dark. Experiments around the world are attempting to capture a stray dark matter particle in hopes of understanding it, but so far they have turned up empty.
Recently, a team of theorists has proposed a new way to hunt for dark matter using weird “particles” called magnons, a name I did not just make up. These tiny ripples could lure even a fleeting, lightweight dark matter particle out of hiding, those theorists say. [The 11 Biggest Unanswered Questions About Dark Matter]
We know all sorts of things about dark matter, with the notable exception of what it is.
In the summer of 1935, the physicists Albert Einstein and Erwin Schrödinger engaged in a rich, multifaceted and sometimes fretful correspondence about the implications of the new theory of quantum mechanics.
The focus of their worry was what Schrödinger later dubbed entanglement: the inability to describe two quantum systems or particles independently, after they have interacted.
Until his death, Einstein remained convinced that entanglement showed how quantum mechanics was incomplete. Schrödinger thought that entanglement was the defining feature of the new physics, but this didn’t mean that he accepted it lightly.
Photons normally do not interact with each other, but researchers found that they can get particles of light to interact with each other like matter does. They produced particles called Floquet polaritons.
Photons — those fundamental particles of light — have a slew of interesting properties, including the fact they don’t tend to crash into one another. That hasn’t stopped physicists from trying, though.
University of Chicago physicists have now come up with a new, highly flexible way to make photons behave more like the particles that make up matter. It might not give us lightsabers, but making photons collide could still lead to some fantastic technologies.
The trick to getting particles of light — which have no mass — to acknowledge one another’s existence is to have them meet in the quiet confines of an atom, and combine their properties with those of an electron.
Credit where credit is due: Evolution has invented a galaxy of clever adaptations, from fish that swim up sea cucumber butts and eat their gonads, to parasites that mind-control their hosts in wildly complex ways. But it’s never dreamed up ion propulsion, a fantastical new way to power robots by accelerating ions instead of burning fuel or spinning rotors. The technology is in very early development, but it could lead to machines that fly like nothing that’s come before them.
You may have heard of ion propulsion in the context of spacecraft, but this application is a bit different. Most solar-powered ion spacecraft bombard xenon atoms with electrons, producing positively charged xenon ions that then rush toward a negatively charged grid, which accelerates the ions into space. The resulting thrust is piddling compared to traditional engines, and that’s OK—the spacecraft is floating through the vacuum of space, so the shower of ions accelerate the aircraft bit by bit.
You’ve read your last complimentary article this month. To read the full article, SUBSCRIBE NOW. If you’re already a subscriber, please sign in and and verify your subscription.
Every type of atom in the universe has a unique fingerprint: It only absorbs or emits light at the particular energies that match the allowed orbits of its electrons. That fingerprint enables scientists to identify an atom wherever it is found. A hydrogen atom in outer space absorbs light at the same energies as one on Earth.
Lurking behind Einstein’s theory of gravity and our modern understanding of particle physics is the deceptively simple idea of symmetry. But physicists are beginning to question whether focusing on symmetry is still as productive as it once was.
Unifying all the forces and particles would require a particle accelerator far more powerful than humans have ever built.
