Lifeboat Foundation

Generating, losing and reviving entanglement

In their experiment, the researchers generated entangled photons by sending light from a high-power “pump” laser into a nonlinear crystal. Under conditions where the photons’ energies and momenta are conserved, one pump photon will produce two entangled photons in a process called spontaneous parametric down conversion (SPDC). The two photons are entangled in all their properties. If a photon is detected at one location, for example, the position of the other entangled photon is automatically determined. The correlation exists for other quantities as well, such as momentum, angular position and orbital angular momentum.

As seen through the witness without any corrective measures, the researchers observed that position entanglement between photons disappears after about 4 cm of propagation. On the other hand, something interesting happens for angular-position entanglement. It disappears after about 5 cm of propagation, but after the photons have travelled another 20 cm, entanglement appears again (see figure). The researchers corroborated their experimental results qualitatively with a numerical model.

A team of researchers at the University of Minnesota Twin Cities has uncovered a way to manipulate objects using ultrasound waves, paving the way for contactless movement in industries like manufacturing and robotics without the need for an internal power source.

The findings have been published in the peer-reviewed journal Nature Communications.

Continue reading “Not Science Fiction: A New Method To Move Objects Without Contact” »

The biggest obstacle is that each robotics lab has its own idea of what a conscious robot looks like. There are also moral implications to building robots that have consciousness. Will they have rights, like in Bicentennial Man?

Considerations about conscious robots have been the domain of science fiction for decades. Isaac Asimov wrote several novels, including I, Robot, that examined the implications from the perspectives of law, society, and family, raising a lot of moral questions. Experts in ethical technology have considered and expanded upon these questions as scientists like those in the Columbia University lab work toward building more intelligent machines.

Science fiction has also brought us killer machines like in The Terminator, and conscious robots sound like a good way to have some. Humans might learn bad ideas and act upon them, and there is no reason to believe that robots will not fall into the same trap. Some of science’s greatest minds have warned against getting carried away with artificial intelligence.

Microsoft Corp. is in discussions to invest as much as $10 billion in OpenAI, the creator of viral artificial intelligence bot ChatGPT, according to people familiar with its plans.

What’s ahead for retail, from the metaverse and AI to Gen A’s spending power and an increased focus on sustainability.

In episode 220 of the Stem Cell Podcast, we chat with Dr. Michael Levin, the Director of the Allen Discovery Center and a Distinguished Professor of Biology at Tufts University. He talks about regenerating frog legs, using bioelectricity to direct development, and the potential applications of xenobots.

Roundup Papers:
1) https://go.nature.com/3NR8aaG
2) https://go.nature.com/3NFeGkT
3) https://bit.ly/39tYFiM
4) https://bit.ly/3HrKY0g.

Continue reading “Developmental and Synthetic Biology featuring Dr. Michael Levin | The Stem Cell Podcast” »

A van der Waals crystal, niobium oxide dichloride, with vanishing interlayer electronic coupling and considerable monolayer-like excitonic behaviour in the bulk, as well as strong and scalable second-order optical nonlinearity, is discovered, which enables a high-performance quantum light source.

Gemenefherbak was a vizier. As such, he was responsible for justice, a function symbolized by the pendant picturing the goddess Maat on his collar.

The chest is protected by a winged scarab, a personification of the reborn morning sun. On the back of the Sarcophagus, the deceased is shown twice worshiping the Djed-Pillar, a symbol of Osiris, lord of the underworld.

In spite of the size of the object and the hardness of the stone, the sculptors express all their virtuosity in the polish of surfaces and in a sophistication of detail that is typical for the 26th Dynasty.

That general question is still hard to answer, again in part because of those pesky errors. (Future quantum machines will compensate for their imperfections using a technique called quantum error correction, but that capability is still a ways off.) Is it possible to get the hoped-for runaway quantum advantage even with uncorrected errors?

Most researchers suspected the answer was no, but they couldn’t prove it for all cases. Now, in a paper posted to the preprint server arxiv.org, a team of computer scientists has taken a major step toward a comprehensive proof that error correction is necessary for a lasting quantum advantage in random circuit sampling — the bespoke problem that Google used to show quantum supremacy. They did so by developing a classical algorithm that can simulate random circuit sampling experiments when errors are present.