Lifeboat Foundation

The shape of our Universe has long been recognized to be flat. But that isn’t the only possibility.

Born shortly after the Big Bang, these cosmic monsters have perplexed astronomers for years. A new study may shed light on their origins.

Astronomers believe that new measurements from NASA’s Hubble Space Telescope confirm that the Universe is expanding about 9% faster than expected based on its trajectory seen shortly after the big bang.

This means that the Hubble constant (H0) — the measure of the current expansion rate of the Universe, named after Edwin Hubble, the man who first observed said expansion — needs adjustment from its current figure of ~2 × 10-¹⁸ s-¹.

Adam Riess, Bloomberg Distinguished Professor of Physics and Astronomy at The Johns Hopkins University, Nobel Laureate, says of the disparity between old calculations and these new findings: “This mismatch has been growing and has now reached a point that is really impossible to dismiss as a fluke. This is not what we expected.”

In 2016, Attila Krasznahorkay made news around the world when his team published its discovery of evidence of a fifth force of nature. Now, the scientists are making news again with a second observation of the same force, which may be the beginning of a unified fifth force theory. The researchers have made their original LaTeX paper available prior to acceptance by a peer-reviewed journal. Study of the hypothesized fifth force, a subfield all by itself, is centered on trying to explain missing pieces in our understanding of physics, like dark matter, which could be expanded or validated by an important new discovery or piece of evidence.

Everything in our Universe is held together or pushed apart by four fundamental forces: gravity, electromagnetism, and two nuclear interactions. Physicists now think they’ve spotted the actions of a fifth physical force emerging from a helium atom.

It’s not the first time researchers claim to have caught a glimpse of it, either. A few years ago, they saw it in the decay of an isotope of beryllium. Now the same team has seen a second example of the mysterious force at play — and the particle they think is carrying it, which they’re calling X17.

If the discovery is confirmed, not only could learning more about X17 let us better understand the forces that govern our Universe, it could also help scientists solve the dark matter problem once and for all.

At almost every frontier in theoretical physics, scientists are struggling to explain what we observe. We don’t know what composes dark matter; we don’t know what’s responsible for dark energy; we don’t know how matter won out over antimatter in the early stages of the Universe. But the strong CP problem is different: it’s a puzzle not because of something we observe, but because of the observed absence of something that’s so thoroughly expected.

Why, in the strong interactions, do particles that decay match exactly the decays of antiparticles in a mirror-image configuration? Why does the neutron not have an electric dipole moment? Many alternative solutions to a new symmetry, such as one of the quarks being massless, are now ruled out. Does nature just exist this way, in defiance of our expectations?

Through the right developments in theoretical and experimental physics, and with a little help from nature, we just might find out.

Calculations involving a higher dimension are guiding physicists toward a misstep in Stephen Hawking’s legendary black hole analysis.

Scientists hope that the future of gravitational wave detection will allow them to directly observe a mysterious kind of black hole.

Gravitational wave detectors have seen direct evidence of black holes with roughly the mass of giant stars, while the Event Horizon Telescope produced an image of a supermassive black hole billions of times the mass of our Sun. But in the middle are intermediate-mass black holes, or IMBHs, which weigh between 100 and 100,000 times the mass of the Sun and have yet to be directly observed. Researchers hope that their new mathematical work will “pave the way” for future research into these black holes using gravitational wave detectors, according to the paper published today in Nature Astronomy.

Physicists use two types of measurements to calculate the expansion rate of the universe, but their results do not coincide, which may make it necessary to update the cosmological model. “It’s like trying to thread a cosmic needle,” explains researcher Licia Verde of the University of Barcelona, co-author of an article on the implications of this problem.

More than a hundred scientists met this summer at the Kavli Institute for Theoretical Physics at the University of California (U.S.) to try to clarify what is happening with the discordant data on the expansion rate of the universe, an issue that affects the very origin, evolution and fate of our cosmos. Their conclusions have been published in Nature Astronomy journal.

“The problem lies in the Hubble constant (H0), a parameter which value—it is actually not a constant because it changes with time—indicates how fast the Universe is currently expanding,” points out cosmologist Licia Verde, an ICREA researcher at the Institute of Cosmos Sciences of the University of Barcelona (ICC-UB) and the main author of the article.