Lifeboat Foundation

JILA researchers have tricked nature by tuning a dense quantum gas of atoms to make a congested “Fermi sea,” thus keeping atoms in a high-energy state, or excited, for about 10% longer than usual by delaying their normal return to the lowest-energy state. The technique might be used to improve quantum communication networks and atomic clocks.

Quantum systems such as atoms that are excited above their resting state naturally calm down, or decay, by releasing light in quantized portions called photons. This common process is evident in the glow of fireflies and emission from LEDs. The rate of decay can be engineered by modifying the environment or the internal properties of the atoms. Previous research has modified the electromagnetic environment; the new work focuses on the atoms.

The new JILA method relies on a rule of the quantum world known as the Pauli exclusion principle, which says identical fermions (a category of particles) can’t share the same quantum states at the same time. Therefore, if enough fermions are in a crowd—creating a Fermi sea—an excited fermion might not be able to fling out a photon as usual, because it would need to then recoil. That recoil could land it in the same quantum state of motion as one of its neighbors, which is forbidden due to a mechanism called Pauli blocking.

The single-cell transcriptional profile of a human embryo between 16 and 19 days after fertilization reveals parallels and differences in gastrulation in humans as compared with mouse and non-human primate models.

Distinct phases of synaptic plasticity contribute to memory formation at different times and in different brain regions.

Rutgers researchers and their collaborators have found that learning — a universal feature of intelligence in living beings — can be mimicked in synthetic matter, a discovery that in turn could inspire new algorithms for artificial intelligence (AI).

The study appears in the journal PNAS.

One of the fundamental characteristics of humans is the ability to continuously learn from and adapt to changing environments. But until recently, AI has been narrowly focused on emulating human logic. Now, researchers are looking to mimic human cognition in devices that can learn, remember and make decisions the way a human brain does.

Some Drosophila species have cryptic sex-ratio drive systems. Here, the authors show rapid expansion of a driver gene family, Distorter on the X, in three closely related Drosophila species on the X chromosome and suppressors on the autosomes.

Solutions to the problems of interstellar travel

Given the insane scale of interstellar distances, how might we extrapolate from the physics we do understand to envisioning possible ways that aliens (or us in the future) could cross the cosmic void? There are a few possible solutions to the problem of interstellar travel.

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There’s a mysteriously shaped cluster of stars at the center of the Andromeda Galaxy, around 2.5 million light-years away and neighbor to the Milky Way. It’s been causing astronomers to furrow their brows and stroke their chins for decades at this point.

However, new research into how galaxies – and the supermassive black holes at their centers – can collide together may offer an explanation for this cluster. It seems that it might be caused by a gravitational ‘kick’, something similar to the recoil of a shotgun but on a cosmic scale.

This latest study suggests the kick would be powerful enough to create an elongated mass of millions of stars – technically known as an eccentric nuclear disk – instead of the sort of symmetric star cluster that would typically be in the center of a galaxy like Andromeda.

For the first time, SpaceX has teamed up with researchers from NASA and several other US institutions to publicly discuss how it plans to use Starship to build Mars Base Alpha.

Save for a handful of comments spread around the periphery of SpaceX and CEO Elon Musk’s main focus, Starship itself, the company and its executives have almost never specifically discussed how the next-generation fully-reusable rocket will be used to create a permanent human presence on Mars. For the most part, that clear focus on near-term hurdles is hard to fault. Half a century of mostly theoretical analysis has made it abundantly clear that a permanent and sustainable extraterrestrial human outpost is impossible without a radical reduction in the cost of access to space. For decades, NASA has studied and studied and studied slight variations of a plan that would cost hundreds of billions of dollars to send a few astronauts to Mars for a few months at a time.

Put simply, without a revolution in space transport, even a temporary presence on Mars where inhabitants are mostly dependent on imported goods is infeasible unless Mars exploration is made a national or international priority on the order of tens of billions of dollars per year. Over the 80–90 years that spaceflight has been seriously pondered, dozens of groups and papers and studies and space agencies have imagined what that revolution might look like and SpaceX is not unique for proposing a solution to that longstanding problem. However, SpaceX is the first of that long list of contenders to propose a solution and both invest significant resources and put hammer to metal in an attempt to make that vision real.