Among many other cases of cosmic fine-tuning, physicists had discovered what looked like very precise fine-tuning regarding the Higgs Boson or Higgs mass, which I discuss in my post here. Physicists tried to evade this fine-tuning with a wildly speculative theory called supersymmetry, which was the "foundation of sand" for an even more wildly speculative family of theories called string theory. All of the predictions of supersymmetry failed, and the particles it predicted were never found. To try to sweep under the rug this failure, the string theorist Susskind gives us this bit of hair-splitting:
" I call that string theory with a capital 'S', and I can tell you with 100% confidence that we don’t live in that world. And then there’s string theory with a small 's' – you might call it string-inspired theory....The string landscape is one such guess. It’s not based on absolutely precise capital-S string theory, but on some conjectures about what this expanded small-s string theory might be."
You get the idea? Susskind was trying to preserve his string theory landscape multiverse fantasy by telling us that it is only string theory with a capital "S" that has been ruled out, not string theory with a small "s." This hair-splitting is like when a wife finds her husband naked in bed with his naked mistress, and the husband says, "Don't worry, darling: this merely shows that I have been unfaithful with a small 'u,' not unfaithful with a capital 'U.' "
In a more recent interview, Susskind resorts to the dubious business of consensus-claiming, a form of bandwagon-boasting. Nowadays, the term "consensus" is being used massively by scientists and science journalists, often in a very misleading way. The first thing that should be discussed is: what is meant by the term "consensus"? To get a proper sense of the denotation and connotation of that word, we should look at how "consensus" is defined by various dictionaries. Below is how "consensus" is defined by various dictionaries and authorities:
- A Google search for "consensus definition" gives "a general agreement" as the first result.
- The Merriam-Webster dictionary gives us two definitions of "consensus" that disagree with each other. The first definition is "general agreement; unanimity." The second definition is "the judgment arrived at by most of those concerned." The first definition specifies 100%, and the second definition merely means 51% or more.
- Dictionary.com also gives us two defintions of "consensus" that disagree with each other. The first is "majority of opinion." The second is "general agreement or concord; harmony." The second definition implies near-unanimity; the first does not.
- The Collins dictionary defines "consensus" as "general agreement among a group of people."
- The Britannica dictionary defines "consensus" as "a general agreement about something : an idea or opinion that is shared by all the people in a group."
- Vocabulary.com defines "consensus" as "agreement in the judgment or opinion reached by a group as a whole," and at the very beginning of the page with this definition, we are told that "when there's a consensus, everyone agrees on something."
- The Cambridge Dictionary defines "consensus" in two ways: (1) "a generally accepted opinion among a group of people"; (2) "agreement among a group of people."
- The Macmillan dictionary defines "consensus" as "agreement among all the people involved."
From the definitions above, you can make the following conclusions:
(1) "Consensus" is a word that is often defined as if it meant a unanimous opinion on some topic, but also often defined as if it meant a mere majority opinion on some topic.
(2) Because it is often defined as if it meant a unanimous opinion on some topic, "consensus" is undeniably a word with at least a strong connotation of meaning a unanimous opinion on some topic, with everyone agreeing about it. The connotation of a word is the kind of impression or feeling that the word creates, regardless of how the word is literally defined.
Because it is defined in ways that conflict with each other, "consensus" is a slippery and ambiguous word to be using. You might call it a very treacherous term, a term very prone to mislead or confuse. Since it has two very different definitions, using the word "consensus" is as potentially misleading as using the word "gay" soon after people first started to use that term to mean "homosexual," at a time when it was hard to tell whether "gay" meant "homosexual" or simply "merry."
One of many deceptive speech habits occurring in science literature is that misleading claims are being made of a "scientific consensus" about opinions which do not at all involve any unanimity of opinion among scientists. Because of how often "consensus" is defined to mean "unanimity of opinion," such claims are designed to create an impression that scientists agree about something. But typically there is no evidence that anything close to 100% of scientists agree on such an opinion, and in very many cases there is not even good evidence that a strong majority of scientists believe in the opinion.
Because of the almost total non-existence of secret ballot polls of scientists, there are almost no claims about scientist opinions that are well supported by evidence. We know that certain opinions are what we may call reputed majority opinions of certain types of scientists. For example, it is repeatedly alleged that most cosmologists believe in dark matter and that most biologists believe in the doctrine of common descent, that all species are descended from a common ancestor. But what percentage of cosmologists believe in dark matter, and what percent of biologists believe in the doctrine of common descent?
You cannot tell such a thing by asking for a show of hands at a meeting of cosmologists or a show of hands at a meeting of biologists. When there is a reputed majority of opinion about something in some scientific field, a scientist in that field may think that he will get in trouble by publicly stating an opinion contrary to the majority in his field. So such a scientist may fail to honestly state his opinion whenever he can be publicly identified as someone holding a contrarian opinion.
You can try to figure out what scientists think about a hypothesis by going through their public statements, but that would be a not-very-reliable approach. Publicly scientists will often make statements that do not show a definite belief about something. For example, having read innumerable scientific papers on memory, I know that an extremely common type of statement in such papers is for a neuroscientist to say something like this: "It is commonly maintained that memories are stored in synapses." But what does that tell us about what the author of the paper believes? You cannot tell.
The only way to get a reliable measure of the opinion of a scientist is to do a secret ballot poll, one that includes a variety of belief options including "I don't know" or "I'm not sure." However, such polls are virtually never done. When opinion polls of scientists are done, they typically fail to be secret ballots, and also fail to offer a full spectrum of answers including options such as "I don't know" or "I'm not sure."
In his recent interview fantasy-physics salesman Leonard Susskind gives us this little bit of "go with the herd" talk using the word "consensus":
" Think about the consensus of the largest fraction of physicists working on these things, and you’ll probably be right. The overall consensus of the field tends to be right. Peculiar individuals, no matter how famous they are, no matter how brilliant they are, if they’re off that consensus, and they’ve been off that consensus for a long time, they’re probably wrong. That doesn’t mean for sure that they’re wrong. Don’t look for the weirdos. Look for what the consensus of the majority of well-respected, highly accomplished physicists believe. And you’ll probably be right. "
This is bad advice, because in the fifty years there have been claims of a physicist or cosmologist c0nsensus on ideas that have failed very badly. Specifically:
- Physicists got all excited about a wildly speculative theory called supersymmetry, which has failed all observational tests.
- Not waiting for supersymmetry to be confirmed, physicists built upon it an even more speculative mountain of speculations called string theory, which has never been supported by any evidence.
- Physicists kept telling us most of the universe's mass energy is dark energy, but no one has ever directly observed dark energy, and no has ever been able to connect it to the Standard Model of physics.
- Physicists kept telling most of the universe's matter is dark matter, but no one has ever directly observed dark matter, and no has ever been able to connect it to the Standard Model of physics.
- Physicists and cosmologists got super-excited about something called primordial cosmic inflation theory, a theory that has not been confirmed by any evidence.
So Susskind is way wrong in trying to suggest that it is a sound principle that you should follow what is claimed as a consensus or majority opinion of theoretical physicists. He fails to have any sociological insight about how often stupid herd effects and baseless bandwagons arise in the little belief communities that are the small tribes of theoretical physicists and cosmologists.
What often goes on in the world of science is that misleading claims are made about a consensus when there is no actual agreement among some group of experts. We saw a recent example in an article by cosmologist Ethan Siegel, who has spent decades being a tireless pitchman for the empirically groundless theory of primordial cosmic inflation, invented to try and explain away very precise fine-tuning in the earliest part of the Big Bang. Siegel claimed that "almost everyone" believed in such a theory. 95% of scientists have no opinion on such a theory. And even among the tiny little tribe called cosmologists, it is not true that almost all of them believe in such a theory.
To prove that, you have to do the very hard work of looking for an opinion poll of cosmologists. Scientists are extremely bad about running polls about their own opinions, and it is all but impossible to find a poll of cosmologists. But I found such a poll at the end of a 2016 paper, the one here.
In Question 11 of the poll, on page 77, cosmologists were asked to complete a sentence beginning with "Our understanding of inflation will..." The results were these:
- Only 44% predicted success for the main effort of cosmologists to get evidence for the theory of primordial cosmic inflation, predicting that there would be "primordial B-mode detection" occurring.
- 7% predicted that inflation would be "ruled out."
- 5% predicted there would be a detection of "non-zero spatial curvature," something that would rule out the theory of primordial cosmic inflation.
Clearly at this time there was no unanimity-type consensus in favor of the theory of primordial cosmic inflation, with a significant fraction of cosmologists rejecting it. In the eight years since the poll, there have been big expensive projects trying to get "primordial B-mode detection," but all have failed. If the poll were to be taken today, it would probably show an even larger fraction of cosmologists rejecting the theory of primordial cosmic inflation.
Moreover, the poll discussed above was not a secret ballot poll. The poll makes no claim to have followed a secret ballot methodology. Whenever scientists are given an opportunity to confess to some belief regarded as heresy, you will always get a much higher rate of people confessing to such a heresy if you do a secret ballot poll.
So Siegel's claim that "almost everyone" supports the theory of primordial cosmic inflation was false. The same writer sometimes claims that almost all cosmologists believe in dark matter. But on page 78 of the 2016 paper, 10% of the polled cosmologists predicted that the theory of dark matter would be "overturned." And in Question 14 of the poll (page 77), 18% of cosmologists predicted that the future would show that dark matter "is modified gravity," a statement equivalent to the belief that dark matter does not really exist. And since this 2016 paper, all searches for dark matter have failed. If you were to do a secret ballot poll of cosmologists today, you may easily find 25% or more rejecting the doctrine of dark matter.
Most claims by scientists about a consensus in some scientist group should be rejected unless they are supported by a well-designed secret ballot poll or are claims about some topic utterly uncontroversial. Since scientists are almost never polled about whether they believe in controversial scientific theories (in well-designed secret ballot polls), almost all claims made about the popularity of such theories are unreliable.
The very idea of using an alleged popularity of some theory as an argument for the theory is a misguided idea. Theories should be defended by facts and arguments, not dubious claims about their popularity. There are all kinds of sociological and economic and psychological and "gone viral" reasons why some theory may become popular in some group of scientists, despite a lack of a sound rationale for the theory. In the case of Susskind's multiverse, it is pretty clear what was the main reason why he conceived the idea. It was mostly analgesic, a very clumsy attempt at irritation relief.
The idea of a multiverse does absolutely nothing to diminish the evidence value of cosmic fine-tuning, for the elementary reason that you do not increase the chance of success of any one trial by increasing the number of random trials. The odds of you throwing a deck of cards into the air and getting a triangular house of cards out of the thrown deck is basically zero. You do not increase by even .000000000001 percent the chance of you ever getting that result by imagining an infinity of card deck throwers. Ditto for universes. Imagining some infinity of them does nothing to increase the chance of getting a habitable universe on any one try.
For a discussion of the reasons why imagining a multiverse does nothing to explain cosmic fine-tuning in our universe, see my posts here and here. Evolutionary biologist Richard Lewontin confessed the willingness of materialists to believe in absurd explanations, a willingness stemming from their zeal to exclude purposeful divine agency. He stated this:
"Our willingness to accept scientific claims that are against common sense is the key to an
understanding of the real struggle between science and the supernatural. We take the side
of science in spite of the patent absurdity of some of its constructs, in spite of its failure to
fulfill many of its extravagant promises of health and life, in spite of the tolerance of the
scientific community for unsubstantiated just-so stories, because we have a prior commitment, a commitment to materialism. It is not that the methods and institutions of science
somehow compel us to accept a material explanation of the phenomenal world, but, on
the contrary, that we are forced by our a priori adherence to material causes to create an
apparatus of investigation and a set of concepts that produce material explanations, no
matter how counter-intuitive, no matter how mystifying to the uninitiated. Moreover,
that materialism is absolute, for we cannot allow a Divine Foot in the door."
The quote above by Lewontin is found on page 27 of the paper "Balloons on a String: A Critique of Multiverse Cosmology" by Bruce L. Gordon, an excellent expose of multiverse nonsense, which can be read here. On page 28 he states this:
"So with all due respect to Leonard Susskind and his
coterie of devout string landscape naturalists, there is no landscape of mathematical possibilities that gives rise to a megaverse of actualities and provides a mindless solution to the problem
of cosmological fine-tuning, for even an infinite arena of mathematical possibilities lacks the
power to generate one solitary universe.
The mindless multiverse 'solution' to the problem of fine-tuning is, quite literally, a metaphysical non-starter."
That would actually be a futile maneuver
"The standard model for how galaxies formed in the early universe predicted that the James Webb Space Telescope (JWST) would see dim signals from small, primitive galaxies. But data are not confirming the popular hypothesis that invisible dark matter helped the earliest stars and galaxies clump together. Instead, the oldest galaxies are large and bright, in agreement with an alternate theory of gravity, according to new research from Case Western Reserve University published November 12 in The Astrophysical Journal."
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