Lifeboat Foundation

Physicists at the University of Basel have experimentally demonstrated for the first time that there is a negative correlation between the two spins of an entangled pair of electrons from a superconductor. For their study, the researchers used spin filters made of nanomagnets and quantum dots, as they report in the scientific journal Nature.

The entanglement between two particles is among those phenomena in quantum physics that are hard to reconcile with everyday experiences. If entangled, certain properties of the two particles are closely linked, even when far apart. Albert Einstein described entanglement as a “spooky action at a distance.” Research on entanglement between light particles (photons) was awarded this year’s Nobel Prize in Physics.

Two electrons can be entangled as well—for example in their spins. In a superconductor, the electrons form so-called Cooper pairs responsible for the lossless electrical currents and in which the individual spins are entangled.

Physicists have long struggled to explain why the universe started out with conditions suitable for life to evolve. Why do the physical laws and constants take the very specific values that allow stars, planets and ultimately life to develop? The expansive force of the universe, dark energy, for example, is much weaker than theory suggests it should be—allowing matter to clump together rather than being ripped apart.

A common answer is that we live in an infinite multiverse of universes, so we shouldn’t be surprised that at least one universe has turned out as ours. But another is that our universe is a computer simulation, with someone (perhaps an advanced alien species) fine-tuning the conditions.

Continue reading “How to test whether we’re living in a computer simulation” »

Superconducting materials are characterized by the fact that they lose their electrical resistance below a certain temperature, the so-called transition temperature. In principle, they would be ideal for transporting electrical energy over very long distances from the electricity producer to the consumer.

Numerous energy challenges would be solved in one fell swoop: For example, the electricity generated by wind turbines on the coast could be channeled inland without losses. However, this would only be possible if materials were available that have superconducting properties at normal room and ambient temperatures.

In 2019, an unusually high transition temperature of minus 23 degrees Celsius was measured in experiments coordinated by the Max Planck Institute in Mainz. The measurement took place at a compression pressure of 170 gigapascals—1.7 million times higher than the pressure of the Earth’s atmosphere. The material was a lanthanum hydride (LaH_10+δ), a compound of atoms of the metal lanthanum with hydrogen atoms. The report on these experiments and other similar reports remain highly controversial. They have internationally aroused great interest in research on lanthanum hydrides with different compositions and structures.

The fine structure constant is one of the most important natural constants of all. At TU Wien, a remarkable way of measuring it has been found—it shows up as a rotation angle.

One over 137: This is one of the most important numbers in physics. It is the approximate value of the so-called fine structure constant—a physical quantity that is of outstanding importance in atomic and particle physics.

There are many ways to measure the fine structure constant—usually it is measured indirectly, by measuring other physical quantities and using them to calculate the fine structure constant. At TU Wien, however, an experiment has now been performed, in which the fine structure constant itself can be directly measured—as an angle.

The James Webb Space Telescope (JWST) has just scored another first: a detailed molecular and chemical portrait of a distant world’s skies.

The telescope’s array of highly sensitive instruments was trained on the atmosphere of a “hot Saturn”—a planet about as massive as Saturn orbiting a star some 700 light-years away—known as WASP-39 b. While JWST and other space telescopes, including Hubble and Spitzer, have previously revealed isolated ingredients of this broiling planet’s atmosphere, the new readings provide a full menu of atoms, molecules, and even signs of active chemistry and clouds.

Continue reading “James Webb Space Telescope reveals an exoplanet atmosphere as never seen before” »

NASA’s Imaging X-ray Polarimetry Explorer allowed scientists to probe a distant blazar, shedding new light on the cosmic giants.

Scientists made observations of bright, shining jets of particles shooting out of a supermassive black hole and they published their findings in a paper in Nature.

Investigating a blazar with state-of-the-art instruments.

Continue reading “Scientists observe bright jets of light shooting from black hole like never before” »

A new proposal seeks to solve the paradox of quantum spin.

According to the Standard Model of Particle Physics, the Universe is governed by four fundamental forces: electromagnetism, the weak nuclear force, the strong nuclear force, and gravity. Whereas the first three are described by Quantum Mechanics, gravity is described by Einstein’s Theory of General Relativity. Surprisingly, gravity is the one that presents the biggest challenges to physicists. While the theory accurately describes how gravity works for planets, stars, galaxies, and clusters, it does not apply perfectly at all scales.

While General Relativity has been validated repeatedly over the past century (starting with the Eddington Eclipse Experiment in 1919), gaps still appear when scientists try to apply it at the quantum scale and to the Universe as a whole. According to a new study led by Simon Fraser University, an international team of researchers tested General Relativity on the largest of scales and concluded that it might need a tweak or two. This method could help scientists to resolve some of the biggest mysteries facing astrophysicists and cosmologists today.

The team included researchers from Simon Fraser, the Institute of Cosmology and Gravitation at the University of Portsmouth, the Center for Particle Cosmology at the University of Pennsylvania, the Osservatorio Astronomico di Roma, the UAM-CSIC Institute of Theoretical Physics, Leiden University’s Institute Lorentz, and the Chinese Academy of Sciences (CAS). Their results appeared in a paper titled “Imprints of cosmological tensions in reconstructed gravity,” recently published in Nature Astronomy.

Realizing that matter and energy are quantized is important, but quantum particles isn’t the full story; quantum fields are needed, too.