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Yesterday, in the New York Review of Books, Freeman Dyson analyzed a trio of recent books on humanity’s future in the larger cosmos. They were How to Make a Spaceship: A Band of Renegades, an Epic Space Race, and the Birth of Private Spaceflight; Beyond Earth: Our Path to a New Home in the Planets; and All These Worlds Are Yours: The Scientific Search for Alien Life.

Dyson is “a brilliant physicist and contrarian,” as the theoretical astrophysicist Lawrence Krauss recently told Nautilus. So I was waiting, as I read his review, to come across his profound and provocative pronouncement about these books, and it came soon enough: “None of them looks at space as a transforming force in the destiny of our species,” he writes. The books are limited in scope by looking at the future of space as a problem of engineering. Dyson has a grander vision. Future humans can seed remote environments with genetic instructions for countless new species. “The purpose is no longer to explore space with unmanned or manned missions, but to expand the domain of life from one small planet to the universe.”

Dyson can be just as final in his opinions on the destiny of scientific investigation. According to Krauss, Dyson once told him, “There’s no way we’re ever going to measure gravitons”—the supposed quantum particles underlying gravitational forces—“because there’s no terrestrial experiment that could ever measure a single graviton.” Dyson told Krauss that, in order to measure one, “you’d have to make the experiment so massive that it would actually collapse to form a black hole before you could make the measurement.” So, Dyson concluded, “There’s no way that we’ll know whether gravity is a quantum theory.”

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Scientists at the University of Calgary successfully teleported a particle nearly four miles away in a breakthrough experiment that could revolutionize the way computers function.

Researchers used the entanglement property of quantum mechanics, known as “spooky action at a distance,” to teleport a particle. It’s a scientific property not even the renowned Albert Einstein could come to terms with it.

“Being entangled means that the two photons that form an entangled pair have properties that are linked regardless of how far the two are separated,” Dr. Wolfgang Tittel, a physics professor at the University of Calgary who was involved in the research, said in a press statement. “When one of the photons was sent over to City Hall, it remained entangled with the photon that stayed at the University of Calgary. What happened is the instantaneous and disembodied transfer of the photon’s quantum state onto the remaining photon of the entangled pair, which is the one that remained six kilometres [slightly less than 4 miles] away at the university.”

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Researchers from the Graphene Flagship use layered materials to create an all-electrical quantum light emitting diodes (LED) with single-photon emission. These LEDs have potential as on-chip photon sources in quantum information applications.

Atomically thin LEDs emitting one photon at a time have been developed by researchers from the Graphene Flagship. Constructed of layers of atomically thin materials, including transition metal dichalcogenides (TMDs), graphene, and boron nitride, the ultra-thin LEDs showing all-electrical single photon generation could be excellent on-chip quantum light sources for a wide range of photonics applications for quantum communications and networks. The research, reported in Nature Communications, was led by the University of Cambridge, UK.

The ultra-thin devices reported in the paper are constructed of thin layers of different layered materials, stacked together to form a heterostructure. Electrical current is injected into the device, tunnelling from single-layer graphene, through few-layer boron nitride acting as a tunnel barrier, and into the mono- or bi-layer TMD material, such as tungsten diselenide (WSe2), where electrons recombine with holes to emit single photons. At high currents, this recombination occurs across the whole surface of the device, while at low currents, the quantum behaviour is apparent and the recombination is concentrated in highly localised quantum emitters.

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This is the question tackled by theoretical physicists working on quantum gravity by creating models attempting to reconcile gravity and quantum mechanics.

Some of these models predict that spacetime at the Planck scale (10^-33cm) is no longer continuous — as held by classical physics — but discrete in nature.

Just like the solids or fluids we come into contact with every day, which can be seen as made up of atoms and molecules when observed at sufficient resolution. A structure of this kind generally implies, at very high energies, violations of Einstein’s special relativity (a integral part of general relativity).

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Quantum encryption uses the principle of “quantum entanglement” to foster communication that’s totally safe against eavesdropping and decryption by others.

The satellite’s true military nature is being disguised under the civilian name, Quantum Experiments at Space Scale, or QUESS. Publicly, QUESS is being billed as an international research project in the field of quantum physics.

Micius or Mozi is operated by the Chinese Academy of Sciences (CAS) while the University of Vienna and the Austrian Academy of Sciences run the satellite’s European receiving stations. The quantum satellite was launched last Aug. 16 from the Jiuquan Satellite Launch Center in the Gobi Desert.

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