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Tiny particles are interconnected despite sometimes being thousands of kilometers apart—Albert Einstein called this “spooky action at a distance.” Something that would be inexplicable by the laws of classical physics is a fundamental part of quantum physics. Entanglement like this can occur between multiple quantum particles, meaning that certain properties of the particles are intimately linked with each other.

Entangled systems containing multiple offer significant benefits in implementing quantum algorithms, which have the potential to be used in communications, or quantum computing. Researchers from Paderborn University have been working with colleagues from Ulm University to develop the first programmable optical quantum memory. The study was published as an “Editor’s suggestion” in the Physical Review Letters journal.

Quantum computing and communication often rely on the entanglement of several photons together. But obtaining these multiphoton states is a bit like playing the lottery, as generating entanglement between photons only succeeds a small fraction of the time. A new experiment shows how to improve one’s odds in this quantum game of chance. The method works like an entanglement assembly line, in which entangled pairs of photons are created in successive order and combined with stored photons.

The traditional method for obtaining multiphoton entanglement requires a large set of photon sources. Each source simultaneously generates an entangled photon pair, and those photons are subsequently interfered with each other. The process is probabilistic in that each step only succeeds in producing pair entanglement, say, once in every 20 tries. The odds become exponentially worse as entanglement of more and more photons is attempted.

Christine Silberhorn from Paderborn University, Germany, and her colleagues have developed a new method that offers a relatively high success rate [1]. They use a single source that generates pairs of polarization-entangled photons in succession. After the first pair is created, one of these photons is stored in an optical loop. When the source creates a new pair (which can take several tries), one of these photons is interfered with the stored photon. If successful, this interference creates a four-photon entangled state. The process can continue—with new pairs being generated and one photon being stored—until the desired multiphoton state is reached.

The rise of quantum computing and its implications for current encryption standards are well known. But why exactly should quantum computers be especially adept at breaking encryption? The answer is a nifty bit of mathematical juggling called Shor’s algorithm. The question that still leaves is: What is it that this algorithm does that causes quantum computers to be so much better at cracking encryption? In this video, YouTuber minutephysics explains it in his traditional whiteboard cartoon style.

“Quantum computation has the potential to make it super, super easy to access encrypted data — like having a lightsaber you can use to cut through any lock or barrier, no matter how strong,” minutephysics says. “Shor’s algorithm is that lightsaber.”

According to the video, Shor’s algorithm works off the understanding that for any pair of numbers, eventually multiplying one of them by itself will reach a factor of the other number plus or minus 1. Thus you take a guess at the first number and factor it out, adding and subtracting 1, until you arrive at the second number. That would unlock the encryption (specifically RSA here, but it works on some other types) because we would then have both factors.

Three scientists who laid the groundwork for the understanding of the odd “entangling” behavior of quantum particles have received the 2022 Nobel Prize in Physics.

French physicist Alain Aspect, Austria’s Anton Zeilinger and American John Clauser were honored for their experiments exploring the nature of entangled quantum particles.

A NASA X-ray spacecraft delivers new dimensions to the first images from the Webb telescope.


Images touch people in a way that words cannot. The unprecedented clarity of the Webb telescope’s first scientific images dazzled people across the world when they became public on July 12, 2022. Three months later, the team working on NASA’s Chandra X-Ray Observatory released new images of the same target objects: Stephan’s Quintet, galaxy cluster SMACS 0723.3–7327, and the “Cosmic Cliffs” of the Carina Nebula. An image that Webb later took of the Cartwheel Galaxy also got an update. All these visuals add more “turbulent” information about these structures and give the originals a whole new dimension.

The full set of images is available here. To appreciate the new data, Inverse set some of them side by side with their corresponding original image.

Electronic computing and communications have advanced significantly since the days of radio telegraphy and vacuum tubes. In fact, consumer devices now contain levels of processing power and memory that would be unimaginable just a few decades ago.

But as computing and information processing microdevices get ever smaller and more powerful, they are running into some fundamental limits imposed by the laws of quantum physics. Because of this, the future of the field may lie in photonics—the light-based parallel to electronics. Photonics is theoretically similar to electronics but substitutes photons for electrons. They have a huge potential advantage in that photonic devices may be capable of processing data much faster than their electronic counterparts, including for quantum computers.

STOCKHOLM — Three scientists jointly won this year’s Nobel Prize in physics Tuesday for proving that tiny particles could retain a connection with each other even when separated, a phenomenon once doubted but now being explored for potential real-world applications such as encrypting information.

Frenchman Alain Aspect, American John F. Clauser and Austrian Anton Zeilinger were cited by the Royal Swedish Academy of Sciences for experiments proving the “totally crazy” field of quantum entanglements to be all too real. They demonstrated that unseen particles, such as photons, can be linked, or “entangled,” with each other even when they are separated by large distances.

It all goes back to a feature of the universe that even baffled Albert Einstein and connects matter and light in a tangled, chaotic way.

Aspect, Clauser, and Zeilinger won the prize for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science.

The Nobel Prize in Physics has recently been announced.

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics 2022 to Alain Aspect, John Clauser, and Anton Zeilinger for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science.