18-year-old Ewin Tang has proven that classical computers can solve the “recommendation problem” nearly as fast as quantum computers. The result eliminates one of the best examples of quantum speedup.
Read more
Category: quantum physics
Sometimes, while waiting for quantum computers to become a thing, or complaining that your stupid laptop keeps dying on 5 percent battery, it’s easy to forget just how far technology has come over the past 50 years.
Sure, we can all list off a whole bunch of innovations that have changed the way the world works — the Internet, smartphones, radio telescopes — but it’s hard to really put that kind of change into perspective.
Thankfully, pictures often speak louder than words, and so below are nine photos that’ll make you stop and raise your *praise hand* emojis to the sky in honour of the scientists and engineers that have got us where we are today.
Read more
Some physicists claim the popular landscape of universes in string theory may not exist.
- By Clara Moskowitz on July 30, 2018
Read more
Using advanced fabrication techniques, engineers at the University of California San Diego have built a nanosized device out of silver crystals that can generate light by efficiently “tunneling” electrons through a tiny barrier. The work brings plasmonics research a step closer to realizing ultra-compact light sources for high-speed, optical data processing and other on-chip applications.
The work is published July 23 in Nature Photonics.
The device emits light by a quantum mechanical phenomenon known as inelastic electron tunneling. In this process, electrons move through a solid barrier that they cannot classically cross. And while crossing, the electrons lose some of their energy, creating either photons or phonons in the process.
Read more
The Casimir force and superconductivity are two well-known quantum effects. These phenomena have been thoroughly studied separately, but what happens when these effects are combined in a single experiment? Now, Delft University of Technology have created a microchip on which two wires were placed in close proximity in order to measure the Casimir forces that act upon them when they become superconducting.
Is vacuum really empty? Quantum mechanics tells us that it’s actually swarming with particles. In the 1940s, Dutch physicists Hendrik Casimir and Dirk Polder predicted that when two objects are placed in very close proximity, about a thousandth of the diameter of a human hair, this sea of ‘vacuum particles’ pushes them together – a phenomenon known as the Casimir effect. This attractive force is present between all objects and even sets fundamental limits to how closely we can place components together on microchips.
Superconductivity is another well-known quantum phenomenon, also discovered by a Dutchman, Heike Kamerlingh Onnes, in the early 20th century. It describes how certain materials, such as aluminum or lead, allow electricity to flow through them without any resistance at cryogenic temperatures. Over the last 100 years, superconductors have revolutionized our understanding of physics and are responsible for magnetically levitated trains, MRI scans and even mobile phone stations.
Read more
