A Debate Over How The Universe Began
Even though it’s commonly accepted today, the Big Bang theory was not always the universally accepted scientific explanation for how our universe began. In fact, the term ‘Big Bang’ was coined by a prominent physicist in 1948 to mock the idea.
In the middle of the 20th century, researchers in the field of cosmology had two warring theories. The one we would come to call the Big Bang suggested the universe expanded rapidly from a primordial, hot, and ultra-dense cosmos. Conversely, the so-called ‘Steady State’ theory held that the universe, at any given point in time, looked roughly the same.
The story of how the Big Bang became the accepted theory of physics is also a story of two men. One, Fred Hoyle, was a steady state supporter who thought the universe would last forever. Meanwhile, George Gamow, the major public advocate of the Big Bang, begged to differ. They debated in the pages of Scientific American and in competing popular books, as both dedicated scientists and earnest popularizers of their field.
And while Gamow ended up winning the debate, for the most part, the two men managed to come together in one way: They accidentally explained the origins of every element of matter by being part right, and part wrong. The truth, it turned out, would lie in the middle.
Ira talks to physicist and science historian Paul Halpern about this story, detailed in his book, Flashes of Creation: George Gamow, Fred Hoyle, and the Great Big Bang Debate.
Invest in quality science journalism by making a donation to Science Friday.
Paul Halpern is a professor of physics at the University of the Sciences in Philadelphia. His most recent book is “Flashes of Creation: George Gamow, Fred Hoyle, and the Great Big Bang Debate.”
IRA FLATOW: This is Science Friday. I’m Ira Flatow. Believe it or not, even though it’s commonly accepted today, the Big Bang theory was not always the universally accepted scientific explanation for how our universe began. In fact, the term “Big Bang” was coined by a prominent physicist to mock the idea.
Here’s some background. In the middle of the 20th century, researchers in the field of cosmology had two warring theories, two opposing theories– one we would come to call the Big Bang, where the universe expanded rapidly from a primordial, hot, ultra-dense cosmos, versus the so-called steady-state theory, where the universe at any given point in time would look roughly the same. The story of how the Big Bang became the accepted theory is also a story of two men– one, Fred Hoyle, a steady-state supporter who thought the universe would last forever, and George Gamow, the major public advocate of the Big Bang, who begged to differ.
They debated in the pages of Scientific American, in competing popular books– in fact, Gamow’s Mr. Tompkins series was my favorite book for understanding relativity as a child. And he turned out to be right for the most part. And Hoyle, despite his many other achievements, is remembered not for his stellar work as a dynamic scientist, but for giving the theory the derisive but popular name “Big Bang.”
As always, there is much more to the story. And here to take us back in time is Dr. Paul Halpern, professor of physics at the University of the Sciences and author of a new book, Flashes of Creation– George Gamow, Fred Hoyle, and the Great Big Bang Debate. He joins us from Philadelphia. Welcome to the program, Paul.
PAUL HALPERN: Thank you so much for having me on Science Friday.
IRA FLATOW: Nice to have you. First, let’s set the scene of what we knew about the universe at the time these two men were supporting opposing theories. Why was the origin of the universe in question at all at that time?
PAUL HALPERN: Well, the origin of the universe scientifically was first examined by Albert Einstein when he developed his general theory of relativity back in 1915. And Einstein found that his theory produced a rather strange solution that would expand over time. And at first, he thought the solution was a big mistake.
But then later, after Edwin Hubble and others mapped out the behavior of galaxies in the universe and saw that all the galaxies except the nearby ones were actually moving away from us faster and faster, that meant that the universe was expanding. And Albert Einstein realized that the universe was growing after all. It was a dynamic cosmos.
So then people such as George Lemaitre, who was a Belgian priest and astronomer, speculated that the universe came from something called a primeval atom, or something that included all the matter in the cosmos, and then it expanded many, many billions of years ago and formed the present-day universe. And then, people start to think, well, are there alternatives to the idea of the universe expanding? And one motivation for that was, when they used Hubble’s data to try to estimate the age of the universe, they came up with 2 billion years or 3 billion years, much less than the age of Earth or the age of stars. So there seemed to be a blatant contradiction between the data they found and the present-day knowledge of the universe, the fact that the universe must have existed before stars were produced. And that’s when Fred Hoyle came up with the idea of the steady-state universe, which expands, but new matter fills in the gaps so it lasts forever.
IRA FLATOW: And why was Fred Hoyle so sure that he was right, that the universe was in this steady state?
PAUL HALPERN: Well, Fred Hoyle was a very instinctive scientist. And he actually came up with the idea of steady state along with two other scientists, Hermann Bondi and Tommy Gold, after seeing a movie. It was a horror movie called The Dead of Night.
And that film has a plot in which the beginning of the film and the end of the film are pretty much the same. Somebody goes to a house and realizes that he experienced the house in his nightmares, later wakes up and the whole thing turns out to be a nightmare, but then he’s invited to the same house again. And everything happens over and over again in the film. And after seeing that film, they went to Hermann Bondi’s apartment, and Tommy Gold said, well, what if the universe is like that?
So they put their minds together, and Fred Hoyle came up with the idea of continuous creation, that small amounts of matter would pop up in the universe very, very slowly over time, and that matter would eventually form stars and galaxies and repopulate the areas where older galaxies move away from. And Hoyle thought that was a much more satisfactory idea of explaining the universe than the Big Bang, because instead of having all the matter created at once, which he derided when he coined the term the Big Bang, he thought that it made more sense to think of matter coming in so slowly that it was undetectable, and therefore science would not be defied.
IRA FLATOW: I have to take a sidetrack here and ask you if you think it’s unusual, in your experience as a physicist and a scientist, to find that inspiration comes from a science fiction horror movie.
PAUL HALPERN: It is unusual, but it’s a rather delightful story. And who knows? They might have been thinking about that in other ways, but looking back, they attributed their discovery to the movie. But people get inspiration in so many ways. There’s a story about Leo Szilard thinking about the chain reaction by reading a science fiction story by HG Wells and coming up with the idea. So people are sometimes inspired by science fiction.
IRA FLATOW: Wow, that’s a great story. And Gamow, where did the idea for the Big Bang come from?
PAUL HALPERN: Well, Gamow took up the idea from others. He was a student of somebody named Alexander Friedmann, who developed one of the first solutions to Einstein’s equations. And like Einstein’s original solution, Friedmann saw that general relativity can lead to an expansion of the universe. And Friedmann did not shy away from that hypothesis, even though there was no real evidence for it at that time.
And Gamow was in Friedmann’s class at the University of Leningrad. And Gamow was inspired by Friedmann, and later, when he developed ideas in nuclear physics, started to think about developing a theory about how all the elements are created. So he decided to combine the idea of nuclear fusion and the idea of the hot early universe and come up with a theory that all the elements in the universe are created at the fiery beginning, which later became known as the Big Bang.
IRA FLATOW: And Fred Hoyle coined the term on a BBC TV show, is that correct?
PAUL HALPERN: It was a BBC radio show that Fred Hoyle was invited onto to talk about his own ideas. And at that time, he wasn’t really so much aware of Gamow’s theories, which were pretty new, but he was aware of Lemaitre’s ideas and other ideas of the expanding universe. So he said, well, there’s steady state and then there’s an alternative, which he called the Big Bang.
And he used that to kind of say, well, isn’t it kind of silly to think about the idea of all the matter being created in a colossal explosion? And explosions were pretty much on people’s minds at the time, because it was only a couple of years after the first atomic bomb blasts. And people really didn’t like the idea of explosions, so it kind of derided the theory if people started associating it with explosions and bombs.
IRA FLATOW: You know, this idea that you just said, the idea that Fred Hoyle would go onto BBC Radio and talk about it in public, this was not unusual for him or George Gamow, correct? They used the popular media to get their points across. They didn’t just argue in scientific papers, but wrote popular science books and even science fiction. Did their ideas about the universe translate easily for the public?
PAUL HALPERN: Well, I think that’s one remarkable thing about both Hoyle and Gamow. It’s because both of them were not only excellent scientists– and arguably, each of them could have won the Nobel Prize– but each of them was also an award-winning popularizer. They both won prizes for their popularizations.
And they both loved Hollywood. Gamow loved westerns, and Hoyle grew up watching movies because his mother played the piano in a cinema for silent movies. She was the accompanist for these movies. So Hoyle grew up watching movies. And they both have a cinematic sense of how to convey science in a very evocative way.
IRA FLATOW: I was very interested in your statement in your book that says, “The epoch of scientists popularizing their own work, for good or bad, had commenced. No longer would theories be hidden in the pages of scholarly books and journals.” This was a turning point, you think?
PAUL HALPERN: Yes. Well, the turning point came about because of new media, so first radio and then television. When people got early televisions in the 1950s, a lot of the reason they bought it is to see Milton Berle and comedy shows. But then, let’s say they wanted an alternative, they might turn to a different channel. And other stations would need material to fill the airwaves, so they would recruit scientists such as George Gamow to talk about their theories. And that became the first science popularization on television.
Of course, there was also the advent of paperback books. You mentioned the Mr. Tompkins series. In the 1950s, people started buying paperbacks, which were very inexpensive, and reading about scientific ideas and debating about them.
IRA FLATOW: I still have my original copy of Mr. Tompkins from back then. You mentioned that, for good or bad. What do you mean, for good or bad, as science popularizers?
PAUL HALPERN: Well, sometimes valid scientific ideas would be overlooked in favor of something that was more marketable to the media. And a good example of that is that Albert Einstein, in his later years, developed all sorts of theories of everything which were not experimentally proven. There was no way of verifying them, and theoretically, they were dubious.
And yet, because Einstein was so famous, they would attract colossal media attention. The media would fight over the right to publicize Einstein’s theories, even knowing that physicists were not really embracing them. In fact, physicists were running away from those theories in favor of things like quantum electrodynamics, and that got no media coverage at all.
IRA FLATOW: You also talk about apocalyptic theories, not on the Einstein level, but about the arrival of Halley’s comet being, well, very dangerous for us.
PAUL HALPERN: Yeah, well, actually, when Gamow was a little boy, Halley’s comet arrived on its periodic journey. And there was a popular science writer, Camille Flammarion, who had speculated that Halley’s comet had an atmosphere that would be poisonous. It turned out that it was a minimal amount of something that could potentially be poisonous in millions and millions of times more concentrated amounts. So it was completely safe. But there was a mass panic because of that. So people were afraid of Halley’s comet in 1910.
IRA FLATOW: We have to take a break, and when we come back, more from Paul Halpern about George Gamow, Fred Hoyle, and the great Big Bang debate.
You’re listening to Science Friday. We’re talking with physicist and author Paul Halpern about his latest book about the disagreements of two once-renowned science communicators and physicists in the middle of the last century. On one side, George Gamow, champion of the Big Bang theory. And on the other side, Fred Hoyle, who thought the universe existed in a steady state rather than one sudden burst of matter and energy.
I’d like to go back to the ways in which these scientists were different, in so many ways, from the classic stereotype. You write about Hoyle, quote, “Throughout his life, he argued strongly that scientists should be literate, proving his own thesis by writing or co-writing numerous well-regarded science fiction books that blended thought-provoking science ideas with intriguing social issues.” You point out that he wrote an opera about Copernicus. He speculated about alien life in his novels, The Black Cloud and A for Andromeda. Wouldn’t you say he was a Renaissance man?
PAUL HALPERN: Yes, both Hoyle and Gamow were Renaissance people. They really believed that culture was just as important as science. Hoyle, as you mentioned, wrote the libretti for operas. He really believed in trying to explore all the facets of life. He was an avid mountain climber.
And Gamow loved to travel and loved to hike and go on motorcycle rides. So they really disproved CP Snow’s conjecture about two cultures not communicating with each other, science and the arts. And in fact, CP Snow was the one who invited George Gamow to write for a magazine called Discover magazine that later led to him writing the Mr. Tompkins series.
IRA FLATOW: Yeah. You write that his numerous popular books and articles contained clever sketches and wordplay and poked fun at his field in puns and parodies. I feel like I would have gotten along with him pretty well, as a pun appreciator myself. Let’s go back a bit to talk about the resolution of the Big Bang argument. As we know, it’s the theory that won and is most widely accepted today. What was the evidence that eventually tipped the scales?
PAUL HALPERN: Well, things were trickling in in the late ’50s and early ’60s, such as, for example, the discovery of quasars, which turned out to be very young, active galaxies in formation, colossal sources of energy. But you only see them in the distant past. You don’t see them in the present, which suggests that the universe evolves.
But the real smoking gun was in 1964 and 1965, when two scientists, Arno Penzias and Bob Wilson, who had borrowed a communications satellite radio detector, had converted it to use– to detect astronomical radio waves, looking at radio waves in the halo of the galaxy, trying to detect those. And they got this unexpected hiss, and they thought maybe it was ambient radio noise or something from New York, which was nearby. They thought it might be the droppings of pigeons, and they called that “white dielectric material,” which they scraped off the detector. And after they had scraped it off and captured all the pigeons– and those pigeon cages are in the Smithsonian– after doing all that, they still saw the hiss, or heard the hiss, I should say, in all directions.
And they had a contact that knew that somebody named Bob Dicke at Princeton was working on a radio detector himself. And that’s because Bob Dicke had this theory that the universe had previous eras in which radio waves could be left over from previous cycles of the cosmos. And that theory predicted that there would be this cold radiation out there. And Dicke was about to build a detector to try to test for that. And when he heard about Arno Penzias and Bob Wilson’s discovery, they drove out there, they looked at the detector, they looked at the evidence, and they said, well, this is evidence of radiation from the early universe.
And Dicke’s associate Jim Peebles immediately did an analysis showing that the theory of the hot Big Bang predicts radiation at exactly that temperature, or approximately that temperature, I should say, of 3 Kelvin, which is 3 degrees above absolute zero. Peebles later found out that Ralph Alpher, who was a student of George Gamow, had done a similar calculation back in the 1940s. So then, after Peebles and Dicke announced the result, and it was all over the press– it was headlines in the New York Times– then George Gamow and Ralph Alpher piped in and said, hey, wait a minute, we did stuff like that back in the 1940s. Perhaps we should get some credit for it.
IRA FLATOW: Did Hoyle ultimately accept this conclusion?
PAUL HALPERN: He briefly went through a Big Bang phase. He thought, well, maybe there’s some validity to the Big Bang and thought about that for couple of years. But he was so proud of the steady-state theory and saw it as so elegant, the idea that the universe could last forever, that eventually he and several other physicists developed an alternative called the quasi-steady state.
And in the quasi-steady-state theory, something else called iron needles, which permeate space– little bit of a hokey idea, but they absorb radiation and rebroadcast it at just the right temperature that the satellites and other instruments predict for the microwave background radiation temperature of the Big Bang. But also, they said that the helium produced in the Big Bang, which was another prediction, could be produced in galaxies instead. So they eventually had their own theory, a variation of steady state, and they held that that theory was valid until the end.
And if somebody questioned Hoyle, he said, well, look, you always have to have alternatives. You don’t want to be the geese following the herd. And in his last book, Hoyle had a photo of a mother goose leading a herd of geese to who knows where, and he thought that Big Bang physicists were exactly like that. They were just following the leader blindly without thinking whether or not the Big Bang was right, but just doing it because it was fashionable. And Hoyle thought that at least you have to entertain alternatives.
IRA FLATOW: Great story. I know that these two scientists disagreed about the fundamental trajectory of the universe. You’ve just been telling us about that. But collectively, right, they managed to explain the origin of about every element of matter.
Gamow thought that Big Bang could explain everything from hydrogen up until gold and beyond. Hoyle thought all matter was created inside stars. And they were both wrong, and they were both right.
PAUL HALPERN: That’s correct. So Hoyle came up with a theory called stellar nucleosynthesis, which says that stars build up the elements during different processes. And one process happens when hydrogen is no longer being burned in the stars, and the stars start to contract. And helium is burned to produce carbon. And then as the stars continue to contract, they get hotter and hotter and produce the higher elements.
Once they reach iron, stars undergo supernova explosions if they’re massive enough, and the rest of the elements are produced in the supernova explosions. And the original elements that were produced are also released in the supernova explosions, which is why the great Carl Sagan said, “We are all made of star stuff,” because everything in our bodies except for the hydrogen and helium– everything around us, I should say, was produced in stars and released during supernova explosions.
But the amount of helium in the universe can only be explained by postulating that it was produced in the Big Bang. But it turns out that the higher elements could not have been produced in the Big Bang because it cooled down very rapidly and was not hot enough to produce any elements beyond helium. So it turns out that Gamow developed the beginning of the story, from hydrogen to helium, and Hoyle and his colleagues developed the end of the story, starting with the elements beyond helium.
IRA FLATOW: You know, it’s interesting that neither of these men won a Nobel Prize for their physics work, even though what they contributed to this breakthrough in our understanding of where matter came from. How would you hope the field of cosmology remembers their contributions?
PAUL HALPERN: Well, interestingly, I guess Gamow could have won the Nobel Prize, but he died fairly young. And at the time when he died, they weren’t really giving too many prizes out for astronomy and cosmology. That became a relatively new thing later on, starting in the 1970s.
And Hoyle really should have won the Nobel Prize for stellar nucleosynthesis, but in his later years, he came up with certain fringe theories that were very unpopular. And I speculate in my book Flashes of Creation why Hoyle didn’t get the prize, but another reason might have been that they thought the person who tested the theory came up with the theory himself. And that was Willie Fowler, who started testing the theory along with two other people, Geoff Burbidge and Margaret Burbidge, who are husband and wife. And that team, which are called B2FH for short, developed stellar nucleosynthesis as a whole. But they can only give the Nobel Prize for three people maximum, and they ended up giving it only to Fowler, which was a great disappointment to those who knew Hoyle came up with the idea originally.
IRA FLATOW: Let’s sum this up and talk about this book being about two creative mavericks with big personalities. And you write that there isn’t necessarily room for such people in physics as it is studied today. And you say that physics, like other sciences, is collaborative and team driven and relies on big data. Is this a good thing, overall, for the progression of the field?
PAUL HALPERN: Well, when Gamow was working, and to some extent when Hoyle was working, it was possible to take some paper, for example, in quantum physics, and apply an equation to something else, and work out the results overnight and publish it and have a groundbreaking discovery. But that era seems to be gone. And that’s because in the 1920s and 1930s, there were so many discoveries in fundamental physics. And that kind of slowed down from the 1940s until the 1960s.
And it’s sad that today, there aren’t so many discoveries in fundamental physics. There are discoveries in applied physics, such as a biophysics, condensed matter, and so forth, which are equally important. But in fundamental physics, there aren’t enough experimental discoveries to justify continuing to come up with new theories.
So that’s why today, physics is done in big labs with giant experiments, such as the LHC experiments in Switzerland. So the experiments require huge teams. And in terms of theories, it’s unlikely that a single person will come up with a breakthrough based on all of the evidence out there and the difficulty in progressing beyond what we know. It just seems like it’s a daunting task and requires many, many calculations and many, many people and many, many theories, not just a single person.
IRA FLATOW: And yet we still have these great mysteries about cosmology, about the universe. I’m talking about dark energy and dark matter, which make up 96% of the universe, and yet we have no idea what they’re made of. Is this not something fitting for a maverick to come along and discover?
PAUL HALPERN: Yeah, that is true. In cosmology, if somebody could come up with a valid explanation for dark energy or dark matter, that would be absolutely amazing. And that would be cause for celebration and a possible avenue for somebody who’s an extremely gifted maverick to make a breakthrough. So pay attention, young people. That’s an area where maybe you can make a mark in cosmology, trying to explain dark matter and dark energy.
IRA FLATOW: This is Science Friday from WNYC Studios. In case you’re just joining us, we’re talking to Science writer and physicist Paul Halpern, author of the book Flashes of Creation– George Gamow, Fred Hoyle, and the Great Big Bang Debate. Any other thoughts that you have about these two giants of their fields, or about where we’re headed in physics now?
PAUL HALPERN: Well, I think it’s remarkable that they were able to do so much and accomplish so much in so many different fields. And Gamow even made a contribution to the science of genetics. He came up with the idea that RNA can encode amino acids in triplets.
You know, that was pretty amazing for him to speculate about that. He came up with the basic idea of combinatorics. Other people developed the specifics, but it’s remarkable that they could do so much in so many fields and also be some of the leading popularizers in their day.
And I think today, unfortunately, people have to make a choice either to be a groundbreaking scientist or a popularizer. It’s hard for me to think of anyone who’s been able to stay extremely active in science to the extent that those physicists did and also be able to be as prolific in terms of science and science fiction today. But it could be possible. But it’s become increasingly unlikely now that things are so specialized.
IRA FLATOW: Yeah. Paul, I want to thank you so much for your time today.
PAUL HALPERN: My pleasure. It was great being on your show.
IRA FLATOW: Great book. Dr. Paul Halpern, author of Flashes of Creation– George Gamow, Fred Hoyle, and the Great Big Bang Debate.