Physicists in France have figured out how to optimise an advanced type of electric rocket thruster that uses a stream of plasma travelling at 72,420 km/h (45,000 mph) to propel spacecraft forward, allowing them to run on 100 million times less fuel than conventional chemical rockets.
Known as a Hall thruster, these engines have been operating in space since 1971, and are now routinely flown on communication satellites and space probes to adjust their orbits when needed. These things are awesome, and scientists want to use them to get humans to Mars, except thereâs one â rather large â problem: the current lifespan of a Hall thruster is around 10,000 operation hours, and thatâs way too short for most space exploration missions, which require upwards of 50,000 hours.
As sci-fi fans will attest, scenes of the distant future arenât too difficult to imagine. Weâve got fleets of intergalactic ships exploring the inscrutable vastness of space. Weâve got legions of hardy settlers terraforming strange, new worlds. Thereâs a great galactic chain of humanity forged through will, knowledge, and intellect stretching across the Milky Way and beyond. At least, thatâs one version. Some would describe a brutal, militaristic future for humanity, or one of disembodied consciousnesses and networks of planet-spanning artificial intelligence. But in each version, thereâs one crucial element that humanity canât do without: energy.
Energy is such a fundamental, critical component to civilization â off-world or not â that Soviet astronomer Nikolai Kardashev in 1964 labeled spacefaring civilizations based on how much energy they consumed; the higher the ranking, the more advanced, as Space.com explains. Weâre talking far, far beyond crude fuel like oil and coal. Earth isnât even a Type I civilization because we havenât harnessed all the energy available on our own planet. By contrast, a Type II civilization would be able to build an energy-harnessing structure like a Dyson sphere around its own sun, as described in Popular Mechanics. After all, all those intergalactic ships, stations, settlements, etc., need power from somewhere, same as they need materials.
The brain comprises billions of interconnected neurons that transmit and process information and allow it to act as a highly sophisticated information processing system. To make it as efficient as possible, the brain develops multiple modules tasked with different functions, like perception and body control. Within a single area, neurons form multiple clusters and function as modulesâan important trait that has remained essentially unchanged throughout evolution.
Still, many unanswered questions remain regarding how the specific structure of the brainâs network, such as the modular structure, works together with the physical and chemical properties of neurons to process information.
Reservoir computing is a computational model inspired by the brainâs powers, where the reservoir comprises a large number of interconnected nodes that transform input signals into a more complex representation.
Researchers at North Carolina State University have discovered a new distinct form of silicon called Q-silicon which, among other interesting properties, is ferromagnetic at room temperature. The findings could lead to advances in quantum computing, including the creation of a spin qubit quantum computer that is based on controlling the spin of an electron.
âThe discovery of Q-silicon having robust room temperature ferromagnetism will open a new frontier in atomic-scale, spin-based devices and functional integration with nanoelectronics,â said Jay Narayan, the John C. Fan Family Distinguished Chair in Materials Science and corresponding author of a paper describing the work published in Materials Research Letters.
Ferromagnetism in materials outside of transition metals and rare earths has excited scientists worldwide for a long time. This is because spin-polarized electrons can be used to process and store information with atomic resolution. However, materials with even numbers of electrons, such as carbon and silicon, without unpaired spins were not considered seriously in terms of bulk ferromagnetism. The dangling bonds in bulk carbon and silicon materials usually reconstruct and eliminate sources of unpaired electrons.
For the first time, researchers using pulsar timing arrays have found evidence for the long-sought-after gravitational wave background. Though the exact source of this low-frequency gravitational wave hum is not yet known, further observations may reveal it to be from pairs of supermassive black holes orbiting one another or from entirely new physics at work in our universe.
A New Window onto Gravitational Waves
In 2016, researchers reported the first detection of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO), opening a new window onto a universeâs worth of collisions between extreme objects like black holes and neutron stars. Though this discovery marked the beginning of a new observational era, many sources of gravitational waves remained beyond the reach of our current detectors on Earth.
Topological phases of matter can enable highly stable qubits with small footprints, fast gate times, and digital control. These hardware-protected qubits must be fabricated with a material combination in which a topological phase can reliably be induced. The challenge: disorder can destroy the topological phase and obscure its detection. This paper reports on devices with low enough disorder to pass the topological gap protocol, thereby demonstrating gapped topological superconductivity and paving the way for a new stable qubit.