January 27, 2023 | David F. Coppedge

Do Cosmologists See Clearly with Chickenwire?

They talk glibly about observing objects billions of light-years away,
but their empiricism is tainted by assumptions.

 

Teachers know the difference between looking and seeing. Students may be staring at the whiteboard as the teacher discusses a subject, but their minds are miles away. Jesus himself remarked that the religious leaders of his day claimed to see, but were actually blinded by their assumptions. Their blindness was worse than the physical blindness of the man born blind Jesus had just healed, because it was willful. He said to the Pharisees who would not believe in the evidence in front of their eyes, “If you were blind, you would have no guilt; but now that you say, ‘We see,’ your guilt remains” (John 9:41) They claimed to be seeing but were virtually blind by dogmatic belief—in this case that Jesus could not have performed a mighty miracle because he was not from God. No amount of protesting by the healed man could change their opinion.

The converse is also true: assumptions can make someone see things that are not there, or are different from what they expect.

Today we look at a confident story from astronomers at the University of California at Berkeley who claim they are seeing objects at the edge of the observable universe. Maybe they’re right; we won’t take issue with that, but how do they know that what they claim to see is as they say it is? Consider an analogy: You’re looking through binoculars at a mirage but there is smoke in the way, partially obscuring the view. Could you claim with any confidence that the hydrogen in the water molecules in the mirage are 9.3% deuterium? It’s not even water to begin with! If you were out there at the distance where you believe the fake lake exists, your theory would be falsified.

In cosmology, getting up close is not possible. You can’t travel to places over 13 billion light-years away to make observations. You are necessarily looking through a lot of intervening space in your line of sight, the contents of which you know imperfectly. Astronomers see through a glass darkly, to borrow a King James Bible expression: there’s a tremendous amount of intervening dust, gas, and time in the way. This makes astronomers’ observations of distant objects, as philosophers say, “theory-laden.” Assuming a big bang, and assuming an unfolding timeline from that singularity, theory dictates what they should see. Observations can be forced into the theory. Anomalies can be explained away with theory rescue devices.

Look at this press release and decide if that is what is going on in their claims.

Chickenwire Cosmology

Deep in a remote valley in South Africa one can find a strange sight: 350 radio dishes made from chickenwire, PVC pipe and telephone poles. With this contraption, big bang cosmologists are performing divination on the early epochs of the universe. Are the spirits they conjure up really there? We’re just asking. Keep in mind that these are the same class of experts who insist they cannot see 94% of the universe, which is made up of mysterious unknown stuff (dark matter and dark energy).

Were galaxies much different in the early universe? (Berkeley News, 24 January 2023).

An array of 350 radio telescopes in the Karoo desert of South Africa is getting closer to detecting “cosmic dawn” — the era after the Big Bang when stars first ignited and galaxies began to bloom.

In a paper accepted for publication in The Astrophysical Journal, the Hydrogen Epoch of Reionization Array (HERA) team reports that it has doubled the sensitivity of the array, which was already the most sensitive radio telescope in the world dedicated to exploring this unique period in the history of the universe.

While they have yet to actually detect radio emissions from the end of the cosmic dark ages, their results do provide clues to the composition of stars and galaxies in the early universe. In particular, their data suggest that early galaxies contained very few elements besides hydrogen and helium, unlike our galaxies today.

We encourage readers to familiarize themselves with this press release, giving the astronomers the benefit of the doubt, and appreciating their dedication to working out in the middle of nowhere on another continent to pursue their dream. But we notice some odd things in the press release that cause concern: how do they know what they claim to know? In the following quotes, notice any disparities between what they actually see and what they expect to see. Keep in mind the analogy of a mirage behind smoke, using binoculars made of chickenwire.

  • When the radio dishes are fully online and calibrated, ideally this fall, the team hopes to construct a 3D map of the bubbles of ionized and neutral hydrogen as they evolved from about 200 million years ago to around 1 billion years after the Big Bang.
  • “This is moving toward a potentially revolutionary technique in cosmology. Once you can get down to the sensitivity you need, there’s so much information in the data,” said Joshua Dillon….
  • But the JWST can see only the brightest of the galaxies that formed during the Epoch of Reionization, not the smaller but far more numerous dwarf galaxies whose stars heated the intergalactic medium and ionized most of the hydrogen gas.
  • HERA seeks to detect radiation from the neutral hydrogen that filled the space between those early stars and galaxies and, in particular, determine when that hydrogen stopped emitting or absorbing radio waves because it became ionized.
  • The fact that the HERA team has not yet detected these bubbles of ionized hydrogen within the cold hydrogen of the cosmic dark age rules out some theories of how stars evolved in the early universe.
  • “Early galaxies have to have been significantly different than the galaxies that we observe today in order for us not to have seen a signal,” said Aaron Parsons, principal investigator for HERA and a UC Berkeley associate professor of astronomy. “In particular, their X-ray characteristics have to have changed. Otherwise, we would have detected the signal we’re looking for.”
  • The new data fit the most popular theories of how stars and galaxies first formed after the Big Bang, but not others.
  • “Our results require that even before reionization and by as late as 450 million years after the Big Bang, the gas between galaxies must have been heated by X-rays. These likely came from binary systems where one star is losing mass to a companion black hole,” Dillon said.

A sci-fi graphic shows where the bubbles should be. The article pauses for a commercial about Big Bang theory to explain what comes next. Joshua Dillon stands smiling by his chickenwire divination device. He must be hungry for lunch.

The HERA team continues to improve the telescope’s calibration and data analysis in hopes of seeing those bubbles in the early universe, which are about 1 millionth the intensity of the radio noise in the neighborhood of Earth. Filtering out the local radio noise to see the radiation from the early universe has not been easy.

“If it’s Swiss cheese, the galaxies make the holes, and we’re looking for the cheese,” so far, unsuccessfully, said David Deboer, a research astronomer in UC Berkeley’s Radio Astronomy Laboratory.

Extending that analogy, however, Dillon noted, “What we’ve done is we’ve said the cheese must be warmer than if nothing had happened. If the cheese were really cold, it turns out it would be easier to observe that patchiness than if the cheese were warm.”

Colleague Aaron Parsons is hungry, too, but he has his heart set on fruit.

“The X-rays will effectively heat up the whole block of cheese before the holes will form,” Dillon said. “And those holes are the ionized bits.”

“HERA is continuing to improve and set better and better limits,” Parsons said. “The fact that we’re able to keep pushing through, and we have new techniques that are continuing to bear fruit for our telescope, is great.”

Do these two really know what they are looking at, or hope to look at, with an array of dishes made of chickenwire, telephone poles and PVC pipe? They will undoubtedly see something, Swiss cheese or fruit or other food for thought. Whether the bubble mirages can be detected through the intervening smoke of radio noise remains to be determined.

If the bubbles fail to appear, they will surely have some rescue devices handy. Instead of a Swiss cheese analogy, perhaps it will be Limburger. Or something totally different, like cow liver or tea leaves. Whatever they think they see, even if it “rules out” Swiss cheese, one prediction is a good bet: the Big Bang Theory will survive. Too much philosophical superstructure depends on it.

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Comments

  • J.Y. Jones says:

    Incredible analysis of the early reports from the JWST! Good job, David! I’m only marginally educated on things 12 billion light years away, but your questions and scenarios are definitely on target. At the very least, the article points out how difficult it is to make deductions from information so far away and so inexact. Thanks for a great article!

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