A new measurement of expanding space-time has been given by giant Cosmic Bubbles

In an effort to reduce the universe’s rate of expansion, the thickens once more.

The rate of the Universe’s accelerating expansion has been narrowed to 67.97 km/s per megaparsec thanks to a new measurement of the Hubble constant, which has produced what a large international team of researchers claims is the most accurate and detailed 3D map of our Universe to date.

Based on “bubbles” produced by the early Universe expanding, it is a major accomplishment in measuring the Hubble constant and in the hunt for the enigmatic dark energy that powers it, but it also exacerbates a persistent crisis facing cosmology.

This is because two methods of measuring the Hubble constant yield consistently different results within two different ranges. By using the Dark Energy Spectroscopic Instrument at Lawrence Berkeley National Laboratory, these results almost completely rule out human error—at least when it comes to this particular technique.

Cosmologer Nathalie Palanque-Delabrouille of Berkeley Lab states, “No spectroscopic experiment has had this much data before, and we’re continuing to gather data from more than a million galaxies every month.”.

“We can already measure the expansion history of our universe at seven different cosmic time slices, each with a precision of 1 to 3 percent, which is astounding given that we have only been collecting data for a year. “.

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A discrepancy between results obtained using standard candles and standard rulers to measure the Hubble constant (H0) gives rise to the Hubble tension, which may be the largest issue facing cosmology at the moment.

Standard candles are Cepheid variable stars and Type Ia supernovae, which have known intrinsic brightness, as we have previously explained. We can determine something’s distance with great accuracy if we know how intrinsically bright it is. We obtain a Hubble constant of approximately 73 km/s per megaparsec from Type Ia supernovae and Cepheid variable stars.

Early Universe signals serve as the foundation for standard rulers. The first light to stream through the Universe approximately 380,000 years after the Big Bang is known as the cosmic microwave background (CMB) and “bubbles” in space known as baryon acoustic oscillations, or BAOs. According to these, the Hubble constant is approximately 67 km/s per megaparsec.

The DESI map was based on BAOs, which are essentially spherical acoustic density waves that passed through the early Universe’s plasma fog. The density of matter in the universe was trapped in these spherical bubbles when the fog lifted. Although it is evident that things have changed, spherical galaxy arrangements can be recognized if you know what to look for.

These bubbles have a known and fixed radius of about 150 megaparsec. Because they know the size of a BAO, astronomers can use that information to determine its distance if they spot one in far-off space. This additionally permits Hubble constant measurements.

DESI measured BAOs as far as it could see while surveying the sky, looking an astounding 11 billion light-years into space-time. And the results were firmly in the camp of standard rule when combined with cosmic microwave background measurements. However, the BAO measurement appears to exclude higher velocities even in the absence of the CMB.

Even when we change the assumptions about the data sample or the cosmic expansion history, we typically find values for H0 in the range of 67–68 km/s per megaparsec. According to physicist Kyle Dawson of the University of Utah, “These BAO data allow us to robustly say that the value of H0 is less than 70 kilometers per second per megaparsec when using a standard ruler calibrated from early Universe physics.”.

There are two possible reasons for the Hubble tension: either the standard ruler from early Universe physics needs to be properly calibrated based on new physics, or some sources of systematic error were overlooked during the bootstrapping process of SN+Cepheid measurements from local geometric distance estimates to Hubble flow distance estimates. “.”.

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The main issue is that, according to recent standard candle measurements obtained with the James Webb Space Telescope, Team 73 kilometers per second per megaparsec appears to be the most likely speed. It appears increasingly improbable that current measurements and data will be able to close the gap between the two speeds. Hence, new physics may actually hold the key to the solution.

Though it provides far better precision than previous generation experiments, which took ten years to obtain, this new measurement is only a step, based on only one year of DESI data. Furthermore, it indicates a few minor departures from the current Lambda cold dark matter (LCDM) model of the Universe, which is predicated on distinct models for both dark energy and dark matter.

“With this increased accuracy, we are now in the regime that we have been looking for for the past 20 years, the regime that will allow us to test the nature of dark energy in a meaningful way,” says Dawson.

“A model that departs from the conventional LCDM model by 2.6 sigma best describes the results using only DESI BAO and CMB. We are all eagerly awaiting the measurements using the three-year sample, even though the level of disagreement with the assumed model of the last 20 years is not yet at the 3-sigma level that justifies evidence for new physics.

The analysis methods we developed in the first year have proven to be reliable, and we anticipate that the upcoming measurements will be much more accurate. ****.

We are eager.