The Big Bang – a good theory while it worked

Since 1964, the Big Bang has been the context for interpreting all of astronomy. The theory has been troubled since 1997 by observations that don’t fit the model. That was the year that accelerating expansion was documented. The most recent observation is that All of Creation is rotating. We don’t even know how to calculate such a thing. The blame for our 60-year universal flight from reality is not in the physics, but in a philosophic idea that goes back to Copernicus.

It’s time to replace the Big Bang Theory.

The immediate impetus for this edition of Unauthorized Science is a new report from the Webb Space Telescope (JWST). But it is not a finding from high-tech observations or deep data analysis. It is not abstruse in the least. In fact, a handful of undergraduates noticed in 2007 [my write-up]. The in-your-face reality is that twice as many galaxies are rotating clockwise, compared to counter-clockwise.

But there are at least seven other observations that cast the Big Bang into doubt.

When Einstein published his theory of gravity in 1915 (the General Theory of Relativity is a theory of gravity), it was recognized as the pinnacle of beauty and elegance in science. A simple insight launched a vast web of computation.

The simple insight: Gravity is curved space-time. The curvature of space-time at each point is proportional to whatever mass is at that point.

The vast web: Einstein knew better than anyone that mass is also energy. And energy looks different as measured by different observers, depending how they are moving. Mass is tied up with energy, and energy with momentum and pressure. On the other side, the curvature of space-time also depends on the motion of the observer experiencing space-time.

By the time he was through with his 10-year journey creating GR, Einstein had translated the simple insight into 256 linked nonlinear partial differential equations. Even with today’s supercomputers, the full set of Einstein’s field equations cannot be solved or approximated; and certainly in 1915, they must have seemed like a cosmic joke — Einstein asks the Old One for his thoughts, and He responds truthfully, but the equation that governs the motion of matter on a cosmic scale is impervious to the human intellect.

The equations were not useless. Physicists were able to show they were consistent with Newton’s gravity so long as the field was weak. They were able to calculate the bending of light near the sun and the precession of Mercury’s orbit because the Sun’s gravitational field is weak.

But the big thinkers wanted to know: What do these equations say about the structure of the universe as a whole?

The first answer was suggested by Alexander Friedmann in 1922. Friedmann noticed that the Einstein equations admit of a simple solution for the simple case of a universe that is the same everywhere. Suppose, for example, that the universe is filled with a random array of stars scattered in all directions uniformly, so that on average the density of stars was the same everywhere. The stars may be moving randomly, but on average they are not moving. The stars may be rotating but in random directions so that on average there is no net rotation.

This came to be dignified with the hifalutin name, the Cosmological Principle. But its content is just as described: If the universe is as simple as it can possibly be, we can solve the equations, otherwise … otherwise we don’t know how to think about the large-scale structure of the universe, so we won’t.

The relationship to Copernicus is that he was the first to challenge the religious belief that the Earth was the center of the universe. The idea that the earth is just one of several planets revolving around the sun became known as the Copernican Revolution (and in fact our modern association with the word “revolution” come from a foundational meaning attached to the hypothesis that the earth is revolving). The religion that said “the Earth is the center of the Universe” was replaced by a religion that said “the earth is not at all special; our place in the Universe is not at all special; and every place is on average just like every other place.”

Are the stars uniformly distributed? Of course not. Ten thousand years ago, hunter-gatherers looking up at the night sky could tell you there is a band across the sky where the stars are so thick they melt together like a cloud. Even in the 1920s, it was known that our sun is part of a galaxy with a flattened disk shape.

In the 1930s, the existence of other galaxies was established, and the Cosmological Principle was modified to say that galaxies, not stars are uniformly distributed. In the 1950s, it was discovered that galaxies are clustered, and the Cosmological Principle was modified to say that clusters of galaxies are uniformly distributed. In the 1980s, the first maps of the sky were compiled, and it became clear that the clusters of galaxies were organized in superclusters, so the Cosmological Principle was modified to say that clusters of clusters of galaxies are uniformly distributed.

Are the clusters of clusters uniformly distributed? I haven’t done the analysis, but most astronomers say “yes”. There are some who say the largest structures we can see (and the largest gaps with no galaxies at all) are of comparable size to the entire visible universe.

Listen to Dr Becky, always informative and entertaining, on the Cosmological Principle.

So far, I’ve described two reasons we know that the Big Bang theory is not consistent with the universe that astronomers can see. First was the spin of the universe, from a survey by Michael Longo and his students, reaffirmed by Lior Shamir and later with a very different method by Oliver Philcox. Will the most recent confirmation from the space telescope make any difference, or will astronomers continue to assume the universe is not rotating because that is what they have always assumed?

Second is the evidence that the largest superclusters and the largest void areas where no galaxies appear are comparable in scale to the entire visible universe.

Here are six more anomalies, not counting small disparities like the Hubble Tension.

The Cosmological Principle derives not from observational evidence but from convenience of calculation and from an extension of the Copernican idea that our vantage on the universe is as perfectly typical as it can be. But to the extent that any evidence is adduced to support the Cosmological Principle it is that the cosmic microwave background is uniform in all directions to within a small fraction of 1%. According to theoretical models of the Big Bang, matter and radiation were moving in lockstep for the first 100,000 years after the Bang, so — by assumption — the uniformity of the microwave background attests to the fact that matter was also uniformly distributed up until the moment (100,000 years after the Bang) that matter and radiation parted company. Subsequently, matter could succumb to gravity and begin clumping into galaxies and stars, while the radiation, unaffected by gravity, continued to spread uniformly.

If you are thinking within the confines of the Big Bang, then the uniformity of the CMB tells us that the distribution of matter started out equally uniform. But this model has always led to contradictions. With the available matter and the available time, the models did not predict that gravity could produce galaxies. More matter had to be added, and the matter had to be invisible and undetectable (“dark”) and it had to be distributed just so. Then, two years ago, the contradictions became much worse. Images from the JWST started coming in and they showed that galaxies were already fully formed when the universe was just 1/30 of its present age. No matter how we torture the models, we cannot get them to be consistent with galaxy formation that fast. (The Scientific American article that I cite in this paragraph is good on the facts, but it is characteristically conservative and narrow-minded. It uses circular reasoning to justify looking for explanations within the Big Bang model even as it cites evidence that the Big Bang model is not working.)

I should add (maybe this carries an essential message, or maybe it’s just a curiosity) — we have no explanation why the radiation when we look North should be almost exactly the same temperature as the radiation when we look South. According to present Big Bang theory, the two regions of the universe with the sources of this radiation are so far apart that they have never been in contact with each other, hence the fact that we find them to be at the same temperature within a few thousandths of a degree is puzzling.

Redshift is the astronomer’s measure of distance. The light from stars includes certain colors that are characteristic of hydrogen atoms or helium atoms, etc. We know the exact color where these peaks and valleys in the light distribution should occur. In all of the distant galaxies we observe, the shape of the color map (= the spectrum) is the same, but all the colors are shifted away from the blue, toward the red end of the spectrum. This is interpreted as the galaxies flying away from us — the commonest way to shift all light toward the red occurs when the thing producing the light and the person observing it are moving apart relative to one another.

In the 1930s, Edwin Hubble established Hubble’s Law — all the distant galaxies are moving away from us, and the further away they are, the faster they are receding. Hubble established this principle when he had independent ways to measure distance and redshift. But today, Hubble’s law is used in reverse to infer distance from redshift. All the maps of the universe we have are based on the assumption that the redshift of a galaxy is proportional to its distance.

But, beginning in the 1970s and continuing through his long career, Halton Arp created a catalog of galaxies that looked to be closely related in the sky but had very different redshifts. He made a compelling case that maybe redshift can be caused by something other than distance, and our entire map of the universe s erroneous.

Common sense tells you that gravity should be slowing down the expansion of the universe. This was expected to be the case all the way from Friedmann’s first solution to the Einstein Field Equations (1922) up through the mid-1990s when telescopes and computers finally developed to the point where the slowing could actually be measured. Then in 1997 — surprise! — two completely independent methods of observation and analysis reported that the expansion was not slowing down, but in fact it was getting faster.

Theoreticians had to respond. What they needed was negative pressure. No, that’s not a typo — your common sense and mine says that it would be a positive pressure that could push matter in the universe apart. But Einstein’s Field Equations don’t comport with common sense. The term that would accelerate expansion corresponds to a negative pressure, and no such thing is known to exist in nature.

In 1915, when Einstein first published his Field Equations, he included a term Lambda that was like a negative pressure. Einstein later took that term out of his equations, and he called it the “greatest mistake of his life” because, without it, he should have been able to predict the Hubble expansion. But in 1997, the theoreticians resurrected Lambda because it would fit the bill to explain why the expansion is accelerating. They gave the Lambda term a new name, “dark energy”, and the search was on for any sign, any indication, any clue what it could be, and what kind of physics gives rise to negative pressure. Twenty-eight years on, the observations have turned up zilch. We still have “dark energy” as a standard hypothesis, and we still have no evidence that it exists and no idea what kind of animal could behave in this way.

I haven’t yet told you why the 1964 discovery of the cosmic microwave background propelled the Big Bang Theory from armchair speculation to the framework within which all astronomy is interpreted. The reason goes back to a prediction made by Alpher, Bethe, and Gamow (1948) which offered to account for the fact that ¼ of the matter in the universe is helium and ¾ is hydrogen. If the universe started off with a “hot” Big Bang, then just enough helium would be created in the First Three Minutes. These three Cornell scientists (with a sense of humor and a familiarity with the Greek alphabet) predicted that the prodigious energy from the hot Big Bang would have been diluted and redshifted over billions of years, but it might still be observable as a cosmic microwave background.

So, when Penzias and Wilson announced their observation of the CMB in 1964, the astronomy community took it as dramatic confirmation of the Hot Big Bang.

With improved knowledge of nuclear chemistry and expanded computer resources, and with the exact value of the microwave temperature known, the calculation of Alpher Bethe and Gamow has been repeated in detail. The prediction about ¼ helium held up, but the best calculation today predicts that there should be a lot more lithium in the universe than we see on earth or in the spectra of stars.

Some people have blamed Elon Musk, but this is a conspiracy theory I haven’t looked into.

Kidding aside, this is an indication of something that we don’t understand, but as a motivation to abandon the Big Bang, it probably doesn’t stand up on its own. According to both theory and observation, lithium is just a few billionths of the matter in the universe, and the discrepancy is about how many billionths.

(This one is a little more philosophical and some physicists won’t talk about it.)

The reason that the Big Bang is physics and not theology is that it is formulated without invoking anything that feels specially “designed”. The word “designed” is what separates evolutionists from creationists and scientists are wary of being caught on the wrong side of that divide.

The initial oomf of the Big Bang was apparently exactly calibrated, as if poised on a knife edge. If the matter had been sent off with a tiny bit more momentum, it would all have floated away forever, remaining a tenuous gas. Gravity would not have been strong enough to create anything like a star or a planet. Had there been just a hair less oomf, the Big Bang would have collapsed back on itself, a Big Crunch within a lifetime of a few thousand years or even a few million years — much too short a time for life to evolve on a planet. As near as we can measure (from the Hubble constant and the density of matter), the oomf of the initial Big Bang was exactly enough to allow the universe to go on expanding forever, but just barely.

Was this a “design” feature? A coincidence? It gets more interesting and more improbable when we look at the fundamental laws of physics. Some numbers that physicists take as arbitrary, like the speed of light and the mass of the electron, also seem to be exactly right to create an interesting universe — not a bit too large or too small.

Paul Davies write about a “Goldilocks universe” — not too hot or too cold, exactly right for life. Most physicists are so eager to avoid the implication that our universe was designed that they are willing to hypothesize billions and trillions and gazillions of other universes. They theorize about a multiverse that no one has ever seen and no one ever will see, and then they say “of course, we’re not in one of those gazillion universes with the wrong amount of oomf; we find ourselves in the universe that is capable of supporting life because we’re living beings.”

This topic is called the “anthropic coincidences” and I’ve written about it here (Sec. 4), and I’ll write more in coming weeks.

(This is my own perspective. It’s my own blog, so I get to say what I think.)

It is well-established that quantum mechanics is about the interaction between physical particles and observers. The observer plays a special role in quantum physics which makes QM different from classical physics. The classical world is objective, one reality, no matter who is looking at it. The quantum world is co-created by the particles that are out there and the observers who decide what to look at.

But, according to the Big Bang theory, there were no observers for the first several billion years of the universe. Truth be told, we are in uncharted territory. We have no hypotheses, not even philosophical speculation about how matter might behave in the absence of anyone to look at it. All of cosmology, including but not limited to Big Bang theory, is based on the idea that unobserved physics will behave exactly like observed physics. We have no reason to think this is true, but we push unthinkingly forward because we don’t know what else to do.

There are still tenure track jobs and research grants aplenty for those who continue to conduct research and interpret results within the context of the standard Big Bang model. But there’s a Nobel prize waiting and ready for the person who can assemble these puzzle piece in a new way that doesn’t have so many holes.