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Jun 4, 2020

Stadium-sized asteroid heading near Earth this week

Posted by in categories: asteroid/comet impacts, existential risks

But it may be taller than the Empire State Building, which is 1,454 feet tall. The asteroid is estimated to be between 820 feet and 1,870 feet in diameter.

The asteroid was first spotted nearly two decades ago and is called 2002 NN4.

Seek and Destroy: How NASA Protects Us from Thousands of Asteroids.

Jun 4, 2020

Light turned into exotic Laughlin matter

Posted by in categories: particle physics, quantum physics

Solving a difficult physics problem can be surprisingly similar to assembling an interlocking mechanical puzzle. In both cases, the particles or pieces look alike, but can be arranged into a beautiful structure that relies on the precise position of each component (Fig. 1). In 1983, the physicist Robert Laughlin made a puzzle-solving breakthrough by explaining the structure formed by interacting electrons in a device known as a Hall bar1. Although the strange behaviour of these electrons still fascinates physicists, it is not possible to simulate such a system or accurately measure the particles’ ultrashort time and length scales. Writing in Nature, Clark et al.2 report the creation of a non-electronic Laughlin state made of composite matter–light particles called polaritons, which are easier to track and manipulate than are electrons.

To picture a Laughlin state, consider a Hall bar, in which such states are usually observed (Fig. 2a). In these devices, electrons that are free to move in a two-dimensional plane are subjected to a strong magnetic field perpendicular to the plane. In classical physics, an electron at any position will start moving along a circular trajectory known as a cyclotron orbit, the radius of which depends on the particle’s kinetic energy. In quantum mechanics, the electron’s position will still be free, but its orbital radius — and, therefore, its kinetic energy — can be increased or decreased only in discrete steps. This feature leads to large sets of equal-energy (energy-degenerate) states called Landau levels. Non-interacting electrons added to the lowest-energy Landau level can be distributed between the level’s energy-degenerate states in many different ways.

Adding repulsive interactions between the electrons constrains the particles’ distribution over the states of the lowest Landau level, favouring configurations in which any two electrons have zero probability of being at the same spot. The states described by Laughlin have exactly this property and explain the main features of the fractional quantum Hall effect, whereby electrons in a strong magnetic field act together to behave like particles that have fractional electric charge. This work earned Laughlin a share of the 1998 Nobel Prize in Physics. Laughlin states are truly many-body states that cannot be described by typical approximations, such as the mean-field approximation. Instead, the state of each particle depends on the precise state of all the others, just as in an interlocking puzzle.

Jun 4, 2020

SpaceX’s Starship SN4 launch vehicle prototype explodes after static engine fire test

Posted by in category: space travel

SpaceX had just conducted yet another static fire test of the Raptor engine in its Starship SN4 prototype launch vehicle on Friday when the test vehicle exploded on the test stand in Boca Chica, Texas. This was the fourth static fire test of this engine on this prototype, so it’s unclear what went wrong versus other static fire attempts.

This was a test in the development of Starship, a new spacecraft that SpaceX has been developing in Boca Chica. Eventually, the company hopes to use it to replace its Falcon 9 and Falcon Heavy rocket, but Starship is still very early in its development phase, whereas those vehicles are flight-proven, multiple times over.

SpaceX had just secured FAA approval to fly its Starship prototype for short, suborbital test flights. The goal was to fly this SN4 prototype for short distances following static fire testing, but that clearly won’t be possible now, as the vehicle appears to have been completely destroyed in the explosion following Friday’s test, as you can see below in the stream from

Jun 4, 2020

Europe bets R&D spending will bring jobs to battered economy

Posted by in categories: biotech/medical, economics, employment

The European Union wants a massive dose of research spending to lift it out of what could be the worst recession in its history. Last week, as part of a €1.85 trillion budget and pandemic recovery proposal, the European Commission, the EU executive arm, unveiled plans to pump €94.4 billion into research over 7 years, nearly €11 billion more than originally planned for the program, called Horizon Europe. But not everyone thinks the money is the best medicine.

Horizon Europe gets €13.5 billion to spend fast, spur growth.

Jun 4, 2020

Forget Dragon, the Falcon 9 rocket is the secret sauce of SpaceX’s success

Posted by in category: space travel

I’ve done crazier things than dry out a radio antenna.

Jun 4, 2020

Joined nano-triangles pave the way to magnetic carbon materials

Posted by in categories: chemistry, nanotechnology, particle physics

Graphene, a two-dimensional honeycomb structure made of carbon atoms with a thickness of only one atom, has numerous outstanding properties. These include enormous mechanical resistance and extraordinary electronic and optical properties. Last year a team led by the Empa researcher Roman Fasel was able to show that it can even be magnetic: they succeeded in synthesizing a molecule in the shape of a bowtie, which has special magnetic properties.

Now, researchers report another breakthrough. Theoretical work from 2007 predicted that graphene could exhibit if it were cut into tiny triangles. Over the last three years, several teams, including the Empa team, have succeeded in producing the so-called triangulenes, consisting of only a few dozen , by chemical synthesis under ultra-high vacuum.

Jun 4, 2020

A Digital Locksmith Has Decoded Biology’s Molecular Keys

Posted by in categories: biotech/medical, robotics/AI

Neural networks have been taught to quickly read the surfaces of proteins — molecules critical to many biological processes. The advance is already being used to create defenses for the virus responsible for COVID-19.

Jun 4, 2020

Graphene and 2-D materials could move electronics beyond ‘Moore’s law’

Posted by in categories: computing, mobile phones, nanotechnology, particle physics

A team of researchers based in Manchester, the Netherlands, Singapore, Spain, Switzerland and the U.S. has published a new review on a field of computer device development known as spintronics, which could see graphene used as building block for next-generation electronics.

Recent theoretical and experimental advances and phenomena in studies of electronic spin transport in and related two-dimensional (2-D) materials have emerged as a fascinating area of research and development.

Spintronics is the combination of electronics and magnetism, at the nanoscale and could lead to next generation high-speed electronics. Spintronic devices are a viable alternative for nanoelectronics beyond Moore’s law, offering higher energy efficiency and lower dissipation as compared to conventional electronics, which relies on charge currents. In principle we could have phones and tablets operating with spin-based transistors and memories.

Jun 4, 2020

The mystery is over: Greek mathematician successfully solves 78-year-old maths problem

Posted by in category: mathematics

A Greek mathematician has found the answer to a mind boggling maths problem that has remained unanswered for 78 years – until now.

Associate Professor of Mathematics Dimitris Koukoulopoulos together with Oxford University research professor James Maynard, has solved the Duffin and Schaeffer Conjecture.

First expressed in 1941 by mathematicians R J Duffin and A C Schaeffer, the last time a mathematician showed promise in solving the problem was in 1990. But it wouldn’t be until 29 years later that it would be fully proven by Koukoulopoulos and Maynard – two relatively young mathematicians, both aged in their 30’s.

Jun 4, 2020

A new 3D map illuminates the ‘little brain’ within the heart

Posted by in categories: genetics, neuroscience

Microscopy and genetic studies yield a comprehensive map of the nerve cells found in the heart of a rat.