“Scientists know our universe is expanding. Now, they have a better idea how fast.
Cosmologists who study the universe know that it began with the big bang and that it has been expanding from a single point ever since. Even about 14 billion years later, this expansion moves objects like galaxies in it farther away from us. Scientists try to determine the rate of expansion because it can help tell us how old the universe is.
An international gathering of experts last year in Switzerland confirmed that objects recede faster as they become more distant. For instance, a galaxy 3 million light-years away will move away from us by 46 miles per second, the scientists calculated. A galaxy at twice that distance would be moving away at about 90 miles per second.
The rate, detailed recently in a study published in the journal Astronomy and Astrophysics, is the most precise ever calculated. It is also mind-bogglingly small: If you took an empty space the size of a football field, and it was expanding at the rate our universe is, it would take more than 1 million years to expand by a single centimeter, said study author Caroline Huang, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics.
The calculation has called into question a major scientific theory. It is about 10% faster than what the standard model of cosmology -- essentially our theory of how everything works in the universe -- says the rate should be.
This means there is probably something missing from the standard model, or a force we don't fully understand, said Stefano Casertano, an astrophysicist at the Space Telescope Science Institute in Baltimore and study co-author. Dark matter, the invisible cosmic glue that holds galaxies together, and dark energy, which pushes them apart, are two likely culprits.
The discrepancy also raises questions about what experts thought they knew about the end times.
Currently, a prevailing theory is that the universe will keep expanding until it experiences "heat death" -- stars will lose all their fuel and die in about 100 trillion years or so, leaving everything cold and dark, according to another study co-author, Dillon Brout, from Boston University.
"But now that we know there's a crack in our theory of what is governing the universe at the largest scales, we can't make any predictions at all for its fate," Brout said.
"It both keeps me up at night and wakes me up in the morning."” [1]
1. REVIEW --- Science Shorts: Scientists Figured Out How Fast the Universe Is Expanding --- The most precise measurement of the expansion rate ever made suggests an unknown force may be affecting the cosmos. Woodward, Aylin. Wall Street Journal, Eastern edition; New York, N.Y.. 09 May 2026: C4.
Komentarų nėra:
Rašyti komentarą