Is the Big Bang real? What came before the Big Bang? God?
Is so called dark matter finally becoming matter?
However, it appears that the journalistic article promises/exaggerates/diverges too much relative to the abstract of the paper. Even the preprint does not agree! Regrettable!
"Now MIT scientists, as part of the CHIME/FRB Collaboration, are using far-off radio signals to reveal missing matter in the vast space between galaxies. The team has developed a new method to search out missing matter by combining locations of galaxies with detections of fast radio bursts. ...
A fast radio burst, or FRB, is an ultrabright, millisecond flash of radio waves emitted by extremely energetic phenomena in the distant universe. As it travels through space, the signal from a fast radio burst gets stretched, or “smeared,” in time. The more missing matter that it passes through, the more smeared the signal becomes.
The MIT-led team measured the degree of smearing experienced by thousands of FRB signals detected on Earth. Then they compared each FRB smear with locations of galaxies across the universe to determine how much of an FRB’s smearing was due to galaxy matter versus other, missing matter.
The new method revealed not only whether missing matter was present, but also where. Specifically, the researchers discovered that it exists in very diffuse clouds surrounding groups of galaxies. These clouds extend out from the galaxies, to much further distances than scientists had predicted. ..."
From the abstract:
"The dispersion of extragalactic fast radio bursts (FRBs) can serve as a powerful probe of the diffuse plasma between and surrounding galaxies, which contains most of the Universe’s baryons.
By cross-correlating the dispersion of background FRBs with the locations of foreground galaxies, we can study the relative spatial distributions of plasma and galaxies on scales of 0.1 to 50 Mpc, which are strongly affected by feedback processes in galaxy formation.
Here, we present the measurement of the dispersion-galaxy angular cross-power spectrum between 2870 FRBs from the Second CHIME/FRB Catalog and nearly 6 million galaxies from the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Survey.
Over five photometric galaxy redshift bins spanning 0.05 <𝑧 <0.5 and at 4.9𝜎 significance, we make the first definitive detection of spatial correlations in FRB dispersion measure due to cosmic structure.
While parameter inferences should be interpreted with caution because of incomplete modeling of both the signal and systematic errors, our data indicate that the plasma-galaxy cross-power spectrum cuts off relative to the matter power spectrum at a scale 𝑘−1 cut=0.84+0.46 −0.34 Mpc.
This scale is consistent with those x-ray stacking analyses that suggest dark-matter halos with group-scale masses are largely evacuated of their baryons by feedback processes.
Our Letter demonstrates that FRBs are promising tools to discern the physics of baryonic structure formation and will only become more powerful as FRB surveys expand."
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