Seen through the eyes of giants, the galaxies of our universe cling like bubbles to the surface of an eternal ocean, drawing clumps and threads around an inky void.
This glowing web began billions of years ago as an evenly spread mist of white, hot particles fresh out of the oven of the Big Bang, and then gradually solidified and held together under the guidance of gravity over many years. It cost.
This growth seems slow to us laymen, but University of Michigan physicists Nhat Minh Nguyen, Dragan Hutterer, and Yue-Wei Wen are trying to slow it down even further, and in the process, we’ve discovered some of science’s most troubling tools. I want to solve one of the problems.
Their proposed tweaks to the model that currently best describes our universe could resolve a major discrepancy in observations of the universe’s expanding waistline.
You can complain that you can’t get anything for free these days, or that you have more free space today than you did yesterday. Something is growing out of nothingness, pushing into the interstices of galaxies, and quietly pushing the vast fabric of the universe apart at ever-increasing speeds.
We don’t know what is behind this mysterious thrust, so we call it dark energy.
“If gravity acts like an amplifier that increases perturbations in matter to grow into large-scale structures, dark energy acts like an attenuator that dampens these perturbations and slows the growth of structures.” To tell Nguyen is the lead author of the study on the growth of large buildings.
“By studying how the structure of the universe assembled and grew, we can understand the nature of gravity and dark energy.”
The exact expansion rate, known as the Hubble constant (H0), is not at all clear. Measuring the distance of a certain type of exploding star as it recedes into the distance could yield an acceleration of 74 kilometers per second per megaper second. Using stretched radiation “optical echoes” still bouncing around after the Big Bang (Cosmic Microwave Background (CMB)), H0 approaches about 67 kilometers per second.
It may not seem like a big difference, but with enough research this discrepancy persists and can no longer be dismissed as a minor error.
Mr. Nguyen, Mr. Hutterer, and Mr. Wen. Flat ΛCDM Coincident cosmological models as a potential source of incorrect assumptions. If cosmology were a game of chess, it would be a board and pieces arranged on tiles of general relativity, moved by the propulsion of dark energy and aligned by the gravitational influence of dark matter. Masu.
If we rewind the chess pieces we see today, we can effectively see how the game began in the blink of an eye. rapid inflation From the time when the first stars collapsed, to the formation of galaxies, to the time when they finally emerged as giant interconnected threads.
If for some reason this process deviates from what is predicted by the coincidence model, and the growth of the large-scale structure of the Universe is prevented, the tension between the different measures of the accelerated expansion of the Universe would disappear.
The researchers combined their measurements, including details of cosmic web ripples, gravitational lensing, and the cosmic microwave background, to statistically demonstrate that the cosmic web is growing more slowly than predicted by a flat ΛCDM-consistent cosmology model. A convincing conclusion was reached.
“These growth rate differences that we potentially are finding become more pronounced as we move closer to the present.” To tell Mr. Nguyen.
“These different spacecraft individually and collectively show growth suppression. Either we’re missing some systematic error in each of these spacecraft, or we’re missing some new late stages in the standard model. Either the physics is missing.”
There are no clear candidates that could put the brakes on the growth of the cosmic web, but future measurements of the large-scale structure of the universe may at least hint at whether this idea should be explored further. .
It took 13.7 billion years for the universe to look this beautiful. It may take several more years to unravel the secrets of these beautiful cosmological wrinkles.
This research physical review letter.