Lifeboat Foundation

Yesterday, the physics community got hyped-up over rumours that scientists might have finally detected gravitational waves — ripples in the curvature of spacetime predicted by Einstein 100 years ago — and that their observations could be coming to a peer-reviewed journal near you soon.

So far, our understanding of how gravity affects the Universe has been limited to observations of natural gravitational fields created by distant stars and planets. In fact, gravity is the last of the four fundamental forces that humans haven’t figured out how to produce and control. But now André Füzfa, a mathematician at the University of Namur in Belgium, has published a paper proposing a device that could do just that — albeit in tiny doses. And it wouldn’t require any new technology.

Let’s be clear, we’re talking about incredibly small gravitational fields here, not the type of ‘artificial gravity’ that’s used throughout science fiction to keep characters on shows like Star Trek and Battlestar Galactica walking, not floating, around spacecraft. As yet, that technology isn’t possible.

(8 April 2020 — ESA) Astronomers have assumed for decades that the Universe is expanding at the same rate in all directions. A new study based on data from ESA’s XMM-Newton, NASA’s Chandra and the German-led ROSAT X-ray observatories suggests this key premise of cosmology might be wrong.

Konstantinos Migkas, a PhD researcher in astronomy and astrophysics at the University of Bonn, Germany, and his supervisor Thomas Reiprich originally set out to verify a new method that would enable astronomers to test the so-called isotropy hypothesis. According to this assumption, the Universe has, despite some local differences, the same properties in each direction on the large scale.

Widely accepted as a consequence of well-established fundamental physics, the hypothesis has been supported by observations of the cosmic microwave background (CMB). A direct remnant of the Big Bang, the CMB reflects the state of the Universe as it was in its infancy, at only 380 000 years of age. The CMB’s uniform distribution in the sky suggests that in those early days the Universe must have been expanding rapidly and at the same rate in all directions.

The laws of physics imply that the passage of time is an illusion. To avoid this conclusion, we might have to rethink the reality of infinitely precise numbers.

Astronomers have detected two stellar corpses whirling around each other, and they might be producing gravitational waves.

White dwarf stars are what become of stars like our sun after they run out of fuel and turn into leftover hot cores. For many years, researchers have predicted that there should be binary, or two-object, systems made up of white dwarf stars. According to general relativity, two such masses orbiting each other should emit energy in the form of gravitational waves, which are ripples or disturbances in the fabric of spacetime.

O,.,o.

Physicists have conducted the most high-energy test of the speed of light yet, and found that it is still constant, everywhere in the Universe, even in gamma rays spewed out of sources such as exploding stars.

This means that, even at the highest energies we can detect, one of the pillars of Albert Einstein’s theory of special relativity still stands firm.

Continue reading “Physicists Have Tested The Speed of Light at The Highest Energies Yet” »

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In these troubled times, enforced home-working is producing remarkable results for physicists and astronomers.

Shoot a rifle, and the recoil might knock you backward. Merge two black holes in a binary system, and the loss of momentum gives a similar recoil—a “kick”—to the merged black hole.

“For some binaries, the kick can reach up to 5000 kilometers a second, which is larger than the escape velocity of most galaxies,” said Vijay Varma, an astrophysicist at the California Institute of Technology and an incoming inaugural Klarman Fellow at Cornell University’s College of Arts & Sciences.

Continue reading “New method predicts which black holes escape their galaxies” »

A long-held mystery in the field of nuclear physics is why the universe is composed of the specific materials we see around us. In other words, why is it made of “this” stuff and not other stuff?

Specifically of interest are the physical processes responsible for producing heavy elements—like gold, platinum and uranium—that are thought to happen during neutron star mergers and explosive stellar events.

Scientists from the U.S. Department of Energy’s (DOE) Argonne National Laboratory led an international nuclear physics experiment conducted at CERN, the European Organization for Nuclear Research, that utilizes novel techniques developed at Argonne to study the nature and origin of heavy elements in the universe. The study may provide critical insights into the processes that work together to create the exotic nuclei, and it will inform models of stellar events and the early universe.

Philip Anderson, the theoretical physicist whose ideas reshaped condensed matter physics and stretched to the forefront of other fields, died yesterday in Princeton, New Jersey. He was 96. Anderson had spent the past 45 years at Princeton University, which confirmed his death in a statement.

Combative savant made contributions—and enemies—across many fields.