The rate of expansion of the universe presents an interesting puzzle to astronomers. That means it’s growing faster today than would have been expected based on the early days of the universe. Now, the James Webb Space Telescope shows that this difference is not due to measurement error, but may indicate undiscovered physics that could reshape our understanding of the universe. provided compelling new evidence.
Published in astrophysical journal |Estimated reading time: 5 minutes
“The discrepancy between the observed rate of expansion of the universe and the Standard Model predictions suggests that our understanding of the universe may be incomplete,” said Adam Rees, Bloomberg Distinguished Professor and Nobel Prize winner. (Thomas J. Barber, Bloomberg Distinguished Professor of Physics and Astronomy) said. Johns Hopkins University led the study. “Now that NASA’s two flagship telescopes have confirmed each other’s discoveries, we have to accept this. [Hubble tension] This is a very serious problem and a challenge, but also a great opportunity to learn more about our universe. ”
This cosmic conundrum, known as the Hubble tension, arises from a persistent mismatch between two methods of measuring the rate of expansion of the universe. Current observations of the universe consistently yield higher values compared to predictions based on the initial state of the universe. Although this difference may seem small, only 5 to 6 kilometers per megaparsec, it is too large to be ignored as a mere measurement error.
Reese’s team used Webb’s unprecedented infrared vision to analyze the distance to galaxies that had previously experienced supernovae, using three different measurement methods. The results were in surprisingly good agreement with previous Hubble Space Telescope measurements, effectively ruling out telescope errors as the cause of the tension. “The Webb data is like looking into space at high resolution for the first time, and really improves the signal-to-noise ratio of our measurements,” said Xiang Li, a graduate student at Johns Hopkins University. Masu.
The implications of this discovery go far beyond mere numbers. The expansion rate, known as the Hubble constant, does not affect our daily life or even our solar system, but it is an important key to understanding the structure and evolution of the universe since the Big Bang about 13 to 14 billion years ago. It works. Persistent tension between measurements may point to missing pieces in our understanding of the universe, such as previously unknown forms of matter and energy that influenced the universe’s initial expansion .
Glossary
- hubble tension: An unexplained discrepancy between different methods of measuring the rate of expansion of the universe suggests a potential gap in our understanding of astrophysics.
- mega parsec: A vast unit of astronomical distance equivalent to 3.26 million light years. One light year is the distance that light travels in one year (9.4 trillion kilometers).
- standard model of cosmology: A widely accepted framework for explaining how the universe works, calibrated using data from the cosmic microwave background.
TEST YOUR KNOWLEDGE
What is the main difference between the predicted and observed expansion rate of the universe?
The standard model predicts 67 to 68 kilometers per second per megaparsec, but observations show 70 to 76 kilometers per second, with an average of 73 km/second per megaparsec.
Why is confirmation of Hubble measurements with the Webb telescope important?
It rules out telescope measurement errors as the cause of the Hubble tension and suggests that the discrepancy may be due to unknown physics.
What method did the researcher use to validate the measurements?
They measured the distances using three different methods, including analysis of Cepheid variable stars, carbon-rich stars, and the brightest red giant stars in the same galaxy.
According to current theoretical proposals, how would the Hubble tension be resolved?
Potential explanations include initial dark energy, exotic particles, changing electron mass, primordial magnetic fields, or unusual dark matter properties that influence the universe’s initial expansion.
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