“Is our universe extremely unnatural, a weird permutation among countless other possibilities, observed for no other reason than that its special conditions allowed life to arise, or, are the properties of the universe are inevitable, predictable, that is, ‘natural,’ locking together into a sensible pattern?” This is the question, the great unknown, that preoccupies theoretical physicist Nima Arkani-Hamed, a professor at the Institute for Advanced Study (IAS) in Princeton, N.J.
“For all we know, if galactic radiation-emitting civilizations exist, they could be located anywhere in the Milky Way. A signal reaching Earth could thus be as old as about 90,000 years, that is the time it takes for electromagnetic waves to cover the distance between us and the opposite edge of our galaxy, and this time span becomes even larger if we take into account signals from other galaxies. It is thus not unreasonable to think that, at the time we receive a signal, the emitting civilization no longer exist,” wrote Claudio Grimaldi, guest scientist at the Laboratory of Statistical Biophysics (LBS), Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland in an email to The Daily Galaxy.
“We actually saw this decay happen. It’s the longest, slowest process that has ever been directly observed, and our dark matter detector was sensitive enough to measure it,” said Ethan Brown, an assistant professor of physics at Rensselaer Polytechnic Institute about a process that takes more than one trillion times longer than the age of the universe. “It’s amazing to have witnessed this process, and it says that our detector can measure the rarest thing ever recorded.”
Today’s stories include Earth’s algae and moss could survive under the light of another star to Ancient stars of the Milky Way’s center confirmed, and much more.
“If space is truly infinite,” observes Dan Hooper, head of the Theoretical Astrophysics Group at the Fermi National Accelerator Laboratory, in At the Edge of Time, “the implications are staggering. Within an infinite expanse of space, it would be hard to see any reason why there would not be an infinite number of galaxies, stars, and planets, and even an infinite number of intelligent or conscious beings, scattered throughout this limitless volume. That is the thing about infinity: it takes things that are otherwise very unlikely and makes them all inevitable.”
Editor, Jackie Faherty, astrophysicist, Senior Scientist with AMNH. Jackie was formerly a NASA Hubble Fellow at the Carnegie Institution for Science. Aside from a love of scientific research, she is a passionate educator and can often be found giving public lectures in the Hayden Planetarium. Her research team has won multiple grants from NASA, NSF, and the Heising Simons foundation to support projects focused on characterising planet-like objects. She has also co-founded the popular citizen science project entitled Backyard Worlds: Planet 9 which invites the general public to help scan the solar neighbourhood for previously missed cold worlds. A Google Scholar, Faherty has over 100 peer reviewed articles in astrophysical journals and has been an invited speaker at universities and conferences across the globe. Jackie received the 2020 Vera Rubin Early Career Prize from the American Astronomical Society, an award that recognises scientists who have made an impact in the field of dynamical astronomy and the 2021 Robert H Goddard Award for science accomplishments.
“The fate of black holes in a quantum theory of gravity is, in my view, the most important problem in theoretical physics,” said Jorge Pullin, the Horace Hearne professor of theoretical physics at LSU.