April 27, 2017 | David F. Coppedge

Galaxy Evolution Crisis: Start Over

When you see the words “challenging” and “requires substantial revision” in the abstract, you know trouble is coming.

Eleven astronomers from five continents are unanimous: this galaxy doesn’t fit current theory. Here’s what they found, as announced in Nature. (Note: z  is a designation of redshift, interpreted to be a function of remoteness in distance and time. The higher the number, the closer to the big bang in current thinking.)

Finding massive galaxies that stopped forming stars in the early Universe presents an observational challenge because their rest-frame ultraviolet emission is negligible and they can only be reliably identified by extremely deep near-infrared surveys. These surveys have revealed the presence of massive, quiescent early-type galaxies appearing as early as redshift z ≈ 2, an epoch three billion years after the Big Bang. Their age and formation processes have now been explained by an improved generation of galaxy-formation models, in which they form rapidly at z ≈ 3–4, consistent with the typical masses and ages derived from their observations. Deeper surveys have reported evidence for populations of massive, quiescent galaxies at even higher redshifts and earlier times, using coarsely sampled photometry. However, these early, massive, quiescent galaxies are not predicted by the latest generation of theoretical models. Here we report the spectroscopic confirmation of one such galaxy at redshift z = 3.717, with a stellar mass of 1.7 × 10exp11 solar masses. We derive its age to be nearly half the age of the Universe at this redshift and the absorption line spectrum shows no current star formation. These observations demonstrate that the galaxy must have formed the majority of its stars quickly, within the first billion years of cosmic history in a short, extreme starburst. This ancestral starburst appears similar to those being found by submillimetre-wavelength surveys. The early formation of such massive systems implies that our picture of early galaxy assembly requires substantial revision.

Since the turn of the millennium, there’s been a growing trend of “early maturity” as observational tools improve. We’ve reported many of these since the first major NASA press release in 2002, “The Grand Finale Came First” (1/08/02). Another cover story on Science News in 200x compared it to finding an old man in the stellar nursery ward. Similar reports have continued over the years. Each announcement seems to make the same brow-furrowing claim, This challenging observation implies our theories need substantial revision. And yet those revised theories never come. They’re usually relegated to the futureware list. Meanwhile, science media and textbooks continue to teach the standard myth that stars and galaxies evolved gradually over time.

…suggests that extreme star-formation events in the early Universe are not just rare events

The Editor’s Summary of the paper tries to tamp down the crisis. “Deep astronomical surveys have provided evidence for groups of massive, quiescent galaxies at high redshifts, but this poses a problem: theoretical models do not account for galaxies that stopped forming stars so early in the history of the Universe,” the editors say. “The authors suggest that the galaxy formed its stars in an extreme and short starburst within the first billion years of cosmic history, implying that our picture of galaxy formation may need an update.

It ‘may’ need an ‘update’. OK, when is that scheduled? Who is responsible? Who is leading that project? Not the Editors. Not the authors of this paper. In fact, they expect the problem will get worse, not better! You don’t just ‘update’ a sinking ship.

What is clear is that either substantial revisions of the physical ingredients of galaxy formation and possibly our standard model of cold-dark-matter halo assembly are needed to explain the rapid formation, and sudden and deep quenching, of massive galaxies in the very early Universe in a manner reminiscent of pre-cold-dark-matter pictures of galaxy formation. Stellar mass is not a transitory phenomenon and so this observation suggests that extreme star-formation events in the early Universe are not just rare events, they have an important role in early mass assembly and there must exist a substantial population that will be systematically uncovered by future surveys.

Like eyewitnesses, they just report the accident, not fix it. That is somebody else’s problem.

You may have thought only the evolutionary paleontologists had a Cambrian Explosion challenge. No; cosmologists have one, too. Creationists don’t, because they start with the premise that an all-wise, all-powerful Creator purposefully designed a universe and did it quickly. And just as the Cambrian Explosion provides positive evidence for intelligent design, “rapid formation” of mature galaxies does, too. Why? Because a materialist has no cause for rapid formation, sudden and deep quenching, and “extreme star-formation events.” What do you call a scientific explanation without a cause? The old Stuff Happens Law rears its ugly head again. Materialists are not supposed to invoke special conditions for unguided processes. And can unguided processes play ‘an important role’ in anything? That makes no sense. Intelligent agents play roles.

What could these authors possibly be referring to when they say that the evidence of rapid formation in the very early Universe must have occurred “in a manner reminiscent of of pre-cold-dark-matter pictures of galaxy formation”? Here’s one possibility: “In the beginning, God created the heavens and the earth.”


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