New research suggests holographic dark energy could stop the universe’s expansion.
Category: cosmology – Page 33
Two supermassive black holes will collide in 10,000 years, warping space and time.
A Cosmic Collision in the Making
In a galaxy 9 billion light-years away, two enormous black holes are locked in a cosmic dance that will eventually end in a massive collision. These supermassive black holes, each hundreds of millions of times the mass of our sun, are currently orbiting one another. In about 10,000 years, they will merge in a violent event, unleashing enough force to distort space and time by creating gravitational waves—ripples in the universe’s fabric.
One proposed way of examining if such a force could exist is by closely monitoring asteroid trajectories, and few near-Earth asteroids are as well observed as Bennu. A new study by an international team of scientists analyzes Bennu to try and placing constraints on a possible fifth fundamental force in the search of ultralight dark matter.
Bennu, one of the most dangerous near-Earth objects, has been meticulously tracked by optical and radar astrometric data since it was discovered in 1999. As the destination for the OSIRIS-REx asteroid retrieval mission, additional X-band radiometric and optical navigation tracking data added even more trajectory precision. The idea is that any deviation in the expected trajectory of the asteroid could be the result of an unknown fifth force at work. The results of the study were published in the journal Nature Communications Physics.
Weekend posting was delayed by our trip to accept an honor from Caltech… but here it is! Almost entirely about space and science!! Stuff I promise you hadn’t heard before.
We just returned from Pasadena, where Caltech — my alma mater — installed me as Distinguished Alumnus. An honor that I sincerely never expected, given the many brilliant minds I knew when I was there. Reflecting on that is humbling — even ‘imposter syndroming’ — though people kindly urged me to think otherwise.
In today’s delayed posting, I’ll be mostly taking a pause from politics… though the topic of my previous blog — about the likelihood of blackmail poisoning top levels of the U.S. republic — remains horrifically plausible…
Our universe might be growing by absorbing smaller “baby” universes, not just dark energy.
Decomposing the dark matter of sparse autoencoders.
Joshua Engels, Logan Riggs, Max Tegmark MIT 2024 https://arxiv.org/abs/2410.
On mapping concepts in artificial neural networks with sparse autoencoders: we find that map errors exhibit…
Code for our paper ‘Decomposing The Dark Matter of Sparse Autoencoders’ — JoshEngels/SAE-Dark-Matter.
Physicists finally know whether black holes destroy the information contained in infalling matter. The problem is that the answer hasn’t lit the way to a new understanding of space-time.
Your consciousness could travel multiverse when you dream, claim scientists https://interestingengineering.com/science/alternate-reality-in-dreams
The universe’s structure spans a vast network 500 times the size of the moon.
According to ESA, “This first piece of the map already contains around 100 million sources: stars in our Milky Way and galaxies beyond. Some 14 million of these galaxies could be used to study the hidden influence of dark matter and dark energy on the Universe.”
Also, “This is just 1% of the map, and yet it is full of a variety of sources that will help scientists discover new ways to describe the Universe,” Valeria Pettorino, Euclid Project Scientist at ESA, added.
All our science, measured against reality, is primitive and childlike – and yet it is the most precious thing we have. – Albert Einstein (1879−1955)
Astronomers have observed light bending around a black hole, a phenomenon predicted by Einstein’s theory of general relativity. By studying X-rays from a black hole in the Zwicky 1 galaxy, scientists detected unexpected “light echoes” coming from behind the black hole, proving that the black hole’s gravity was curving space-time and allowing light to bend around it.
Although this effect was predicted over a century ago, it’s the first time astronomers have witnessed it. The researchers now aim to investigate how black hole coronas produce intense X-ray flares and continue studying space-time distortion.