Lifeboat Foundation

The empirical fact of short winter days and long winter nights has been known essentially forever, and has driven enormous amounts of human activity including the construction of monuments like the passage tomb at Newgrange that I keep banging on about in previous posts about timekeeping. The correct explanation of the phenomenon has only been understood for around 400 years, dating back to Johannes Kepler’s description of the orbits of the planets.

The change in the relative length of days and nights is due to a combination of the motion of the Earth about the Sun, and the rotation of the Earth on its axis. Specifically, it happens because the Earth’s axis is tilted by about 23 degrees relative to the axis of its orbit. And because angular momentum is conserved, that axis stays pointing in the same direction through the whole orbit, in the same way that a gyroscope on a gimbal mount will remain pointed in the same direction in space as it’s moved around.

Continue reading “Why Is December 21 The Shortest Day Of The Year?” »

A new scientific study says the universe may actually change its own laws of physics to achieve stability and evolution, called “The Autodidactic Universe.”

Physicists are translating commonsense principles into strict mathematical constraints for how our universe must have behaved at the beginning of time.

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It turns out that “nothing” is one of the most interesting somethings in all of physics. Signup for your free trial to The Great Courses Plus here: http://ow.ly/OOOp30beNyt.

Continue reading “The Nature of Nothing | Space Time” »

At this point, the paper mingles cosmology, or the study of the universe and its origins, with biology. “We ask whether there might be a mechanism woven into the fabric of the natural world, by means of which the universe could learn its laws,” the authors write. In other words, a universal law might transcend all scientific fields. That means that the laws of physics, as we know them, could be subject to higher-order laws of the universe that control them—and that we can’t even comprehend.

“Exploring links between fields is crucial because knowledge is not fundamentally compartmentalized,” says Bruce Bassett, professor at the University of Cape Town’s Department of Mathematics and head of the Cosmology Group at the African Institute of Mathematical Sciences in South Africa. We humans are simply narrow-minded. “We segment and compress knowledge into biology, and physics, and sociology because of our limited brains, and the cost of that segmentation and compression is that we easily miss the commonalities and hidden universality between branches of human knowledge.”

The months-long project demonstrates the physics behind the CPUs we take for granted.

Computer chips have become so tiny and complex that it’s sometimes hard to remember that there are real physical principles behind them. They aren’t just a bunch of ever-increasing numbers. For a practical (well, virtual) example, check out the latest version of a computer processor built exclusively inside the Minecraft game engine.

Continue reading “This 8-bit processor built in Minecraft can run its own games” »

Researchers at Kobe University and Osaka University have successfully developed artificial intelligence technology that can extract hidden equations of motion from regular observational data and create a model that is faithful to the laws of physics.

This technology could enable researchers to discover the hidden equations of motion behind phenomena for which the laws were considered unexplainable. For example, it may be possible to use physics-based knowledge and simulations to examine ecosystem sustainability.

The research group consisted of Associate Professor YAGUCHI Takaharu and Ph.D. student CHEN Yuhan (Graduate School of System Informatics, Kobe University), and Associate Professor MATSUBARA Takashi (Graduate School of Engineering Science, Osaka University).

Physicists from Trinity have unlocked the secret that explains how large groups of individual “oscillators”—from flashing fireflies to cheering crowds, and from ticking clocks to clicking metronomes—tend to synchronize when in each other’s company.

Their work, just published in the journal Physical Review Research, provides a mathematical basis for a phenomenon that has perplexed millions—their newly developed equations help explain how individual randomness seen in the natural world and in electrical and computer systems can give rise to synchronization.

We have long known that when one clock runs slightly faster than another, physically connecting them can make them tick in time. But making a large assembly of clocks synchronize in this way was thought to be much more difficult—or even impossible, if there are too many of them.

On April 28, 2021, at 933 UT (3:33 a.m. Eastern Daylight Time), NASA’s Parker Solar Probe reached the sun’s extended solar atmosphere, known as the corona, and spent five hours there. The spacecraft is the first to enter the outer boundaries of our sun.

The results, published in Physical Review Letters, were announced in a press conference at the American Geophysical Union Fall Meeting 2021 on December 14. The manuscript is open-access and freely available to download.

Continue reading “Parker Solar Probe: A spacecraft has ‘touched’ the sun for the first time” »