A groundbreaking study has introduced an innovative approach to the longstanding issue of the “Hubble tension,” the conflict between different measurements of the universe’s expansion rate. It posits that the MOND (Modified Newtonian Dynamics) theory, which accounts for local variations in matter density, could explain these discrepancies.
This theory was proposed in a collaborative effort by researchers from the Universities of Bonn and St. Andrews, offering a fresh angle on the Hubble tension.
The universe’s expansion rate is quantified by the Hubble-Lemaitre constant. Yet, its precise value is debated, as various measurement techniques yield conflicting results, creating the Hubble tension. The researchers from Bonn and St. Andrews suggest that by adopting an alternate gravitational theory, these conflicting values can be reconciled, effectively resolving the Hubble tension. Their findings are detailed in the Monthly Notices of the Royal Astronomical Society (MNRAS).
Elucidating Universe Expansion
Galaxies drift apart as the universe expands, with their separation speed proportional to their distance from each other. Edwin Hubble, a renowned US astronomer, was among the first to identify this relationship.
Calculating the speed of this separation involves knowing the distance between galaxies and applying the Hubble-Lemaitre constant. Observations of distant universe regions suggest a rate of about 244,000 kilometers per hour per megaparsec.
Inconsistencies in Measurement
Alternative methods, like examining type 1a supernovae, closer celestial bodies, reveal different Hubble-Lemaitre constant values, approximately 264,000 kilometers per hour per megaparsec. Prof. Dr. Pavel Kroupa from the University of Bonn points out that these figures indicate a quicker expansion rate near Earth, up to about three billion light-years, an unexpected anomaly.
Recent observations suggest Earth is in a low-density space region, akin to a bubble in a cake, surrounded by denser matter. This setting, as Dr. Indranil Banik from St. Andrews University explains, could cause galaxies within this “bubble” to move away faster than predicted.
Another team observed galaxies 600 million light-years away moving four times faster than the standard cosmological model predicts, further complicating the picture.
A Universe-Scale Bubble
The standard cosmological model, based on Einstein’s gravity theory, doesn’t account for such under-densities. If gravity works as Milgrom’s MOND theory suggests, these under-densities or “bubbles” could exist, and the observed variations in expansion rate would be due to matter distribution irregularities.
The study, “A simultaneous solution to the Hubble tension and observed bulk flow within 250 h−1 Mpc,” by Sergij Mazurenko, Indranil Banik, Pavel Kroupa, and Moritz Haslbauer, was also contributed to by the University of Saint Andrews (Scotland) and Charles University in Prague (Czech Republic), with funding from the British Science and Technology Facilities Council.
Table of Contents
Frequently Asked Questions (FAQs) about Hubble Tension
What is the Hubble Tension?
The Hubble Tension refers to the discrepancy in measurements of the universe’s expansion rate. Different methods of measuring this rate have yielded conflicting values, creating a significant puzzle in cosmology.
How does the MOND theory propose to resolve the Hubble Tension?
The Modified Newtonian Dynamics (MOND) theory suggests that variations in local matter density can explain the discrepancies observed in measurements of the universe’s expansion rate. This theory posits that gravitational forces behave differently than what Einstein’s theory predicts.
What is the significance of the study published in the Monthly Notices of the Royal Astronomical Society (MNRAS)?
The study, conducted by researchers from the Universities of Bonn and St. Andrews, proposes that the MOND theory offers a plausible explanation for the Hubble Tension. It suggests that using an alternative theory of gravity can reconcile the different measurements of the universe’s expansion rate.
How does the expansion of the universe relate to the Hubble-Lemaitre constant?
The expansion of the universe is quantified by the Hubble-Lemaitre constant, a fundamental parameter in cosmology. This constant represents the rate at which galaxies move away from each other, proportional to their distance.
What role do type 1a supernovae play in measuring the universe’s expansion?
Type 1a supernovae are used as a method to measure the universe’s expansion. By determining the distance of these supernovae from Earth and their color shift, which indicates speed, scientists can calculate the value of the Hubble-Lemaitre constant. However, measurements using this method have shown a different value for the constant compared to other methods, contributing to the Hubble Tension.
More about Hubble Tension
- Hubble Tension Explanation
- MOND Theory in Cosmology
- University of Bonn and St. Andrews Study
- Monthly Notices of the Royal Astronomical Society Publication
- Edwin Hubble and the Universe’s Expansion
- Type 1a Supernovae and Cosmic Measurements
- Gravitational Theories and Einstein’s Legacy
- Local Matter Density Variations in Space
- Galactic Movements and Cosmological Constants
- Research on Universe Expansion Rate Discrepancies
4 comments
wow, this study sounds like a game-changer in how we understand the universe’s growth, I mean, if the MOND theory is right, what else have we got wrong about space?
The standard model has its flaws, but I’m skeptical about MOND. I mean, Einstein’s theories have stood the test of time for a reason, right?
This is incredible! It’s like we are living in a bubble in the universe, never thought about it this way. Super cool if you ask me.
not sure if I buy into this, how can a theory from 40 years ago suddenly solve such a big issue like the Hubble tension, feels a bit far fetched to me.