The Edge of the Coffee Table
John Horgan's EDGE talk
Reality Club: End of Horgan?
The End Of Horgan?
This is a discussion which began at the Edge site operated by
. As my attempts to add a post to the discussion (after its apparent
use-by-date) disappeared down an electronic black hole, I eventually emailed my
post directly to all the original Edge participants. The contents of this page
are the result. To those Edge readers who have responded with moral
support but do not wish to make postings, thank you.
Comments by David Wiltshire, Lee Smolin, Philip Anderson, and John Horgan.
Current number of `official' posts: 12
Other posts: 6
|From: David Wiltshire
Having found a forum where I can address
directly, I would like to reply to his
Edge talk and the previous
"Reality Club" discussion, though this will partly involve retracing some
ground covered in my previous articles in the Australian media:
John's "that is what they thought 100 years ago" argument is flawed;
the correct place to start is not an analogy to the past, but simply to make a
list of all the outstanding problems that we still have.
Lee Smolin has given a number of examples here.
that questions about the early
universe are "probably unanswerable in a definitive sense given the dearth
of reliable data" is in fact an admission that he is wrong, because as I
pointed out in the first of my articles above, a huge amount of data
is now being collected which will answer these questions.
John just doesn't want anyone to tell him this because it blows his whole
Definitive tests in observational cosmology are not going to be any overnight
wonder. Because we have no experimental control over conditions in the very
early universe or at the centres of quasars, interpreting the data and making
exhaustive tests that will satisfy everybody is going to take a long time,
certainly tens, maybe hundreds, of years. Many different independent tests will
be need to be made before things are truly decided. As an example, recently
there has been a test of Gaussianity in the spectrum of primordial
perturbations in the cosmic microwave background (see
http://xxx.lanl.gov/abs/astro-ph/9803256) - the present negative result
could be considered a falsification of the inflationary universe scenario;
something which John claimed was untestable in his book. (The jury is still out
on questions relating to matter densities; all we know for certain is that the
density of ordinary clumped cold matter is much less than critical.)
These tests will have to be repeated and many other independent tests will need
to be made before everyone is convinced
one way or another on inflation; the reason being that inflation is
not a closed final theory but is as yet a general speculative
framework of different models with the common feature of an early period of
exponential cosmological expansion driven by at least one scalar field. Thus
some things can still be tweaked. We need lots and lots of data to nail down
what can and cannot be tweaked, and to see whether the essential ideas of
inflation can survive any tweaking. The same goes for any other theories of
cosmology, and, once we get access to early-times data, theories of high-energy
particle physics and quantum gravity.
John describes how great a theory general relativity is phenomenologically,
but he never mentions that the reason physicists want to unify it with quantum
mechanics is not because we are primarily seekers of beautiful mathematical
truths, but because we know for a fact by the singularity theorems of
Hawking and Penrose that under physically reasonable conditions general
relativity breaks down. It is not complete! As long as something so fundamental
as gravity is incomplete the possibility for a major revolution does exist; and
the fact that no obvious attempt at quantum gravity has worked only makes it
more likely that the "final" version may be a revolutionary one.
The interesting time will come when gravitational wave observatories come on
line giving us a view (or rather `sounds'!) of the universe that we have never
had before. To add to what
Oliver Morton has already touched on, I would
mention that space-based detectors in particular will give us access to
lower frequency gravitational waves than ground based observatories (limited
by seismic noise etc) and this will eventually provide us with substantial
hard data about times before the surface of last-scattering (the surface of the
microwave background) at very early times when the universe was opaque to
electromagnetic radiation. This will be the time when all those speculative
"ironic" theories are nailed down. The first space-based detector (LISA) is
only due to be launched in 20 years time, and more than one space-based
detector will be needed to distinguish the cosmological background from the
stochastic background of galactic sources such as white dwarfs. Thus we might
have to wait 30 or 40 years for such data, but the time will come.
I should also mention in passing that questions which John might think are of
the "filling-in kind" might not be. This is the one warning to take from what
happened 100 years ago. The problem of the precession of the perihelion of
Mercury was certainly regarded as a "filling-in" problem back then. One just
needed to find the planet Vulcan. But this extremely small effect turned out to
be a revolutionary problem, not a minor one at all. The solution, which
involved weird ideas such as curved space, defied what was known as "common
sense" in Einstein's day. I can easily picture John transported back in time 70
years ago, railing against general relativity as many others did then because
it defied "common sense". The point is that as long as anything is
unknown it is extremely foolish to pretend any certainty in guessing
at the answers. As long as things are unknown and mysterious we will keep doing
John's use of the term "ironic science" belies the fact that despite all those
books he has read on the philosophy and methodology of science, despite all his
interviews, he still does not ostensibly display any understanding of how
science works. Science does involve forming testable hypotheses, but one cannot
form a testable hypothesis unless one has a consistent logical framework within
which to pose a hypothesis. You cannot write down a sentence before you learn
language. In physics, the language of which is mathematics, this means
constructing a self-consistent mathematical framework. Einstein could not have
arrived at general relativity if he had not known about Riemannian geometry:
19th century "ironic science". The conventional frameworks for quantum gravity
are not mathematically self-consistent. Someone needs to construct such a
framework before physicists can pose any testable hypotheses.
Superstring theory is an attempt at such a framework, and it is still
far from complete or well-understood, although it is compelling because it
succeeds mathematically in places where physically successful theories such as
general relativity fall down. In his book, John described Ed Witten as a
mathematician as if it were a dirty word, in much the same way that
some arrogant physicists refer to their colleagues who write popular books
as mere journalists. Of course Witten is a mathematician, or a
mathematical physicist if you prefer, and proudly so. The contribution he is
trying to make to quantum gravity should be compared to the contribution
Riemann made to general relativity, only Witten at least has an application in
the back of his mind when trying out the various things he does. The difference
between Riemann and Witten is the difference between mathematics and
mathematical physics. Of course pure mathematicians do love Witten's work
nonetheless, because it gives them many new and interesting areas of
mathematics which they can seek to make rigorous, and that is why they gave
Witten the Field's medal. Rigor by itself can mean rigor mortis.
If superstrings come to something they will of course have to give us testable
hypotheses. As yet we have suggestions of such tests, but because string theory
is not completely understood yet the tests are not completely understood
either. Even if string theory itself comes to nothing, it would still be fair
to say it will nonetheless give us deep insights into how we might go about
constructing whatever theory of quantum gravity we will end up with. I agree
with John that hard data is needed, and that is why I think we may have to wait
at least 30 years before we will have the answer. But that is no reason to
rubbish the attempts of the pioneers who are trying to sort out a consistent
mathematical framework in which to pose the questions.
As Lee Smolin says,
John's book is very much a `here and now' thing. When
people accuse John of having no imagination, it is because he seems to lack any
long-term perspective on science. Many things which he writes of as "ironic
science" are "ironic" merely because they are new and people still haven't
worked out ways to collect meaningful data and to make falsifiable hypotheses.
Physics has had the benefit of hundreds of years in which to mature. I will
agree with John that many social sciences presently do look like psychobabble;
but Aristotle's version of physics was psychobabble compared to what we have
had since Galileo and Newton. I do not think that Aristotle's contribution was
worthless; it got people thinking about the questions to ask, and
eventually they did think about the right questions. Even if the people trying
to make mathematical models of economics and societies today are
wide of the mark, it still gets people thinking about the questions involved.
Sciences mature over hundreds, maybe thousands of years. A number of sciences
are still in their infancy, whatever obvious successes they have had to date.
While it is conceivable that one day we could find that all the important
questions that we could think of had been answered, it is grossly
premature to be thinking in such terms now.
Imagining possible futures does not mean abandoning physical laws we already
have. I imagine that new fundamental physics could fundamentally change our
technology, and allow us to explore the nearer parts of the galaxy; but that is
more likely to be due to better means of propulsion, not because we will invent
Star Trek warp drives to beat the speed of light. It is possible that
we will make contact with extra-terrestrial civilizations, but that is more
likely to be via transmissions and robot probes due to the limits set by the
harsh environments of space, even if we can get near to the speed of light some
day by means as yet unknown. The important point is that however long
it takes and however slow communication with extra-terrestrial civilizations
would be, the possibility of such communication would be one of the biggest
revolutions ever for human culture and science. John admits as much; where he
lacks imagination is in not being able to stand back and appreciate that over
timescales of thousands of years these things could well be possible, even
within the limits set by laws of physics `verified' to date.
John's problem is that he is a journalist living in a go-go rush-rush here-now
mode of existence where he encounters people who are happy to hype up their
results. He wants to interview all the famous scientists, and of course a
number of them are pretentious primadonnas. Naturally, we all laugh at
his more cunning put-downs; but the fact that scientists have human foibles
does not validate John's message. If John needs a taste of his own medicine, he
should consider just how pretentious it is to draw the sweeping generalizations
he does from a fleeting Zeitgeist firmly rooted in one decade at the end of the
I am actually very surprised that John thinks that the prevailing culture is a
"gee-whiz, can-do" one; on the contrary, I think that there is a prevailing
mood of pessimism. Because of economic and social constraints the period of
very recent rapid scientific expansion is slowing down. Many of those
interviewed in his book echoed this pessimism. This has nothing to do with the
underlying science, as John mistakenly seems to think. If any of his
interviewees fooled him into thinking that way it is more probably due to the
fact that by virtue of being famous some senior scientists are occasionally
has-beens who, having done their major work, are past their prime and can't
think of anything new. (In the first few chapters so many people were dying not
long after their interviews with John that I started to keep a tally, but
fortunately it didn't pan out.)
The real cause of current pessimism is our present unique point in history. The
world's population has grown at a fantastic pace in recent times, more people
have been doing science than ever before, but at the same time the world is
beginning to reach its maximum carrying capacity in terms of resources and
everyone is future-shocked and disoriented by the effect of rapid technological
changes on our culture. Governments are not going to pay for any science
without limit. The rate of change will slow. But science itself will not be at
an end as long as basic scientific questions are unanswered.
If John is fooled by "gee-whiz, can-do" talk it is because he does not sit down
enough to analyse the motives of the people he interviews, even if he does
sometimes expose them in his vignettes. Of course hard-nosed particle
phenomenologists are happy to rubbish speculative models like superstrings,
especially if they don't understand the mathematics. Of course some
cosmologists and particle theorists are happy to let journalists get away with
grossly hyped-up descriptions of speculative models about the beginning of the
universe, or so-called "theories of everything" - they probably think it will
help the sale of some popular book or other. Equally, I know that the
imperative of selling his own book will be a big potential barrier to John ever
admitting (to himself even?) that he is wrong.
I am as much against the "fawning" in the popular press as John is; perhaps
more so when it's my friends and colleagues who are involved. Having worked in
Stephen Hawking's group
for four years, I know that the tendency of journalists
to treat him like the Oracle of Delphi is too powerful a temptation for him to
resist. Yes, a lot of Stephen's ideas are deeply speculative, but there are
times when you have to speculate to make any real progress in science. There is
always a difficulty in trying to convey to a popular audience what is
speculative and what is not, because what is speculative is still exciting. In
my own dealings with journalists, when I have been critical of the over-hyping
in pieces they write - perhaps I am more critical than the typical interviewee
- I have tended (not intentionally) to cause offence. (Unlike scientists
journalists often lack the thick skin acquired from the system of critical
peer review of one's articles. I hope by now your skin is thicker, John.) I
think that all this over-hype, which is greatly encouraged by our present
mass-media sound-bite culture, does dreadful damage because it does lead
thinking lay-people like John (and even hard-nosed "empirical" physicists like
Philip Anderson) to pour
rubbish on the whole process of speculation, which as I have outlined above is
nonetheless a very vital and valid part of science.
Finally, I am sure that John does not have a hidden anti-science agenda, but
the reason I get extremely upset by what he says is, not only is it wrong, but
the sorts of ideas John espouses are used as a convenient excuse by those who
do have an anti-science agenda in a climate of diminishing resources.
This is what I described in the second half of my
Ockham's Razor article.
The situation for physics in
Australia, in particular, is probably worse that elsewhere, because
historically physics here has been about half the size it is in other OECD
countries (relative to population) whereas biology has been double the average
size. When you start from a small base wholesale destruction can take a long
time to correct. When you see the physics departments of the University of
Queensland and University of Tasmania respectively lose one third and one half
of their staff in the space of a couple of years you have to cry. And these are
respectable older universities by Australian standards. In "lesser" rural
universities physics departments have disappeared entirely, often merging with
engineering departments where the culture does not involve asking fundamental
questions about science, but something completely different.
Perhaps administrators in the United States are wiser, but as Donald Horne
wrote famously 30 years ago "Australia is a lucky country run mainly by
second-rate people who share its luck. It lives on other people's ideas, and,
although its ordinary people are adaptable, most of its leaders (in all fields)
so lack curiosity about the events that surround them that they are often taken
by surprise." With this quality of person still in power and now
overseeing cuts to Australian universities the myth that "science is finished"
makes the cutting all that easier. It is the last thing we need to hear.
To: David Wiltshire
Thanks for your message, most of which I agree with. However,
I think that John has taken enough criticism and that it is probably
as important for those of us who aspire to be doing fundamental
physics to be somewhat more self-critical than we are usually,
given things like the long period before some of our theories
could be tested. In particular I believe that those of us working
in cosmology, quantum gravity, string theory, etc. should try always
to invent ways to falsify our theories, at least in principle.
We should also be always on the lookout for theoretical results
that kill our theories, and we should be very honest with our
colleagues about when a particular theoretical direction has
failed or reached a difficult point. I don't think we always
have done these things, which leaves us vulnerable to criticisms
of the kind John mentions. In particular, I don't think that the
Euclidean quantum cosmology, or no boundary proposal work was
ever very disciplined in these senses, one never got a sense of
what results might be considered to kill this approach. This was
especially problematic given that most calculations were done with
oversimplified finite dimensional models rather than with real
quantum field theories.
This was why, when we began the loop approach with Carlo Rovelli,
we worked hard to find genuine physical predictions, which could
easily, were the experiments done, falsify the theory. We found them,
in the definite predictions of the spectra of the area and volume
operators. We were then also honest about when the hypothesis that
the dynamics of general relativity lead to a good quantum theory failed,
which was when it was found that the dynamics given by the quantization
of general relativity has no good continuum limit, in spite of the fact
that it is a finite quantum field theory which is perfectly sensible in
all other aspects. This has allowed
us to go on and extend the theory, using the results of string theory
on the perturbative side to help us construct a non-perturbative
theory that may have a good classical limit. Whether we can keep
the predictions of the kinematical side of the theory, with its
definite predictions, while modifying the dynamics so as to lead
to a theory with a good continuum limit, is what much of our
current work is directed towards. I believe personally the best
hope for success is in trying to construct a theory whose
perturbative limit is a string theory. But if no theory can be
developed based on the kinematical structure we discovered for
diffeomorphism invariant quantum field theories that has a good
classical limit, then the whole program will be wrong.
If I may say it also, the point of the cosmological natural
selection proposal was that it, and other theories of its kind,
are strongly falsifiable. Many versions of the theory were immediately
falsifiable and the one I presented in my book would be killed by
the discovery of a two solar mass neutron star. Some versions of
inflation are also falsifiable, and will be well tested in the
observations of the MAP and PLANCK satellites. I agree with Paul
Steinhard that standard inflation should be considered killed if
Omega overall is not one, and that other inflationary models are
not worth much study unless they also naturally lead to robust
There are other examples that could be given, two are the public
announcements last summer by Andy Albrecht that the cosmic string
theories disagree with experiment and the papers of Dowker and Kent
showing that the consistent histories approaches to quantum
cosmology run into serious problems and do not show why the
universe is classical. String theory is also rapidly developing
as people attempt to overcome its obvious weaknesses such as
the apparent lack of a unique vacuum, problems with supersymmetry
breaking and the absense of a genuine background independent formulation,
all of which probably must be overcome if the theory is to be
predictive now. (Although it must be stressed that it is easily
falsifiable by Planck scale experiments, so that it is wrong to
say that string theory makes no robust predictions.)
The conclusion I draw from this is that it is perfectly possible to be
doing fundamental physics and cosmology now, in a way that leads to one's
theories being highly vulnerable to either observational falsification or
abandonment becuase of failures on the theoretical side. We have no need
to take refuge in what may be tested in 30 years time. In my view, we are
long passed the stage where quantum gravity and cosmology can go on as
kind of games, without being subject to the rigors of real science. This
requires a kind of flexibility and willingness to abandon hypotheses and
research programs when they are shown wanting. If more people in these
areas were behaving like this, I think we would be far less vulnerable to
criticisms from John Horgan and people like him than we have been.
PS Sorry if this sounds a bit harsh, but I do think that it is true
that a certain number of people have worked in quantum gravity because
they enjoyed the fact that they could speculate without fear of
their ideas being subject to test, and this has hurt the progress of
the field by making it harder for ideas that are testible to emerge.
|From: David Wiltshire
Thanks for your comments. Basically, I wholeheartedly agree; I think we should
all be self-critical. I don't think that people should be excused from trying
to make falsifiable hypotheses in quantum gravity just because it is still
decades before we can see past the surface of last scattering. My point was
simply that we are eventually going to see past the last-scattering surface,
and when it happens it will be one of those rare defining one-off moments in
the history of science that John spoke about always in the past tense.
Literally, a whole new universe will be opened up to us.
I share your reservations about the no-boundary program etc, which is why I
chose to work on black holes rather than quantum cosmology as a student. I do
admire your efforts to make falsifiable tests in quantum gravity; there should
be more of it!
I'm sure that John has had enough criticism. I wouldn't have intervened at all
if it had not been for John recently popping up on our national radio, just at
a time when huge cuts are being made to physics in Australia and some
administrators doing the cutting are on record as saying things which could be
paraphrased as `physics is dead; it's time to study waste treatment'. Although
John says he is not anti-science, in practice his views have a strong resonance
with the anti-science lobby, and for some of us that is a real rather than a
rhetorical issue. John bears a certain moral responsibility for continuing to
push his views even though most of us would consider it a non-issue
Equally I agree that we practioners in the field have a moral responsibility
to be honest about the scope of our results. It's just so difficult when the
popular press always wants hype.
Let me say "Amen" to David Wiltshire. I said these things about cosmology in
a much more condensed form in my
review of Horgan in the THES a year ago
but I am glad to see them modernised and expanded upon. On "filling in",
the simple, boring subject of strongly interacting electrons--as in High Tc
superconductivity--is provoking a typical Kuhnian crisis by stubbornly
refusing to fit any standard mold or even several nonstandard ones in spite
of at least 2 decades of hard work by a lot of bright people (and even more
not-so bright ones!). And I absolutely do not accept his "mysterian" view
of the mind and consciousness. He is just afraid we might find something.
I agree that too much attention has been paid to JH but there are several
reasons for continuing the discussion, of which Wiltshire has given us an
emotionally phrased example--another is just to provoke us into answers
about why we do go on doing science.
To: David Wiltshire
I'm flattered that you have expended so much energy in trying to poke holes in
my end-of-science argument. I haven't responded until now for two reasons. One
is that I'm trying to stay focused on my new book,
Why Freud Isn't Dead. As I
think I said in one of my Edge
postings, the new book address what I think is the most legitmate objection
to The End of Science, that mind-related science
could have a long and glorious future. I'm trying to make an August deadline
for a first draft.
The second reason is that I'm slightly burned out on arguing about The End of
Science, and it takes a lot to goad me into responding. Your postings, while
impassioned and articulate, don't really add anything to what was said by
Oliver Morton and so on.
My responses to them apply to you as well.
I'm moved to write you this note, however, by your kind reference to the
"self-honesty" of my book. May I ask you to be more honest with yourself in
evaluating your own arguments against me? Blaming me for the decline in
prestige and funding of physics in Australia or anywhere else is just silly, an
egregious example of blaming the messenger.
By the way, did you know that Phil Anderson--who expressed solidarity with your
posting--testified against the Superconducting Supercollider in the early
1990's? As much as Phil will deny it, his view of particle physics is closer to
mine than to yours.
If you were more self-honest, you would have to admit that your view that that
observations will one day validate quantum cosmology and inflation and
superstrings is a fringe position in physics. You are not making a rational
argument but a declaration of faith.
I once had faith in the hyperspace future that sustains you and Lee Smolin and
Ed Witten and Michio Kaku and others. I just can't believe in it any more, any
more than I can believe in a benign, just God. Science, real science, took my
Faith in scientific progress is admirable and noble; without it, science would
not exist. But when such faith loses touch with reality, it violates the
scientific spirit. That's where I think you are now, David. Honestly.
|From: David Wiltshire
To: John Horgan
Thanks for surprising me with your response, over which I heartily laughed.
Your ability to set up straw men shows that your talents are obviously wasted
in your present vocation. You should try politics.
I have never professed to a faith that "observations will one day
quantum cosmology and inflation and superstrings". I only know that the energy
regime to which these theories purport to apply (and where already 'validated'
physics is useless) will be definitively tested, given the technology currently
being developed. In fact, as I stated, empirical data which (if it holds up)
will falsify inflation, has already been collected and is
presently being considered
for publication in Ap. J. Lett. I guess one can repeat that
until one is blue in the face but you won't acknowledge it.
I have no emotional attachment to any particular variant of quantum cosmology,
inflation or superstrings, and the more theories that are falsified the better
as far as I'm concerned; it narrows down the search. The more cherished the
beliefs are that are overturned, the more exciting the adventure. The only
faith I profess to is a faith in the power of experiment and empirical
observation. If this central tenet of the scientific method is to be viewed as
a "fringe position" it shows a bizarre prejudgement on your part.
Your problem is that the sample of people you choose to interview self-selects
for those who have an emotional investment in some particular (sometimes
speculative) theory. It's a great thing that you see through the stuff these
people want you to believe. A lack of faith in other scientists is in fact the
first quality needed to being a good scientist. Unfortunately, not being
trained as a scientist you have no criteria on which to independently judge how
much of the stories that people are feeding you is motivated by personal or
other agendas, and how much just could be right.
Whatever "sins" Phil Anderson has committed for whatever political agenda he
has in the funding bun-fight, I still value his irascible comments - people in
quantum gravity need barbs from people like Phil to keep us honest. Privately,
I would often agree with Phil; I am only defending the worth of the process of
speculation, not the ultimate truth of any particular speculations made to
date. I know the only good speculations will eventually be subject to test.
By punishing the whole of science for the self-serving misdemeanours of a few
of the eminent scientists you interview, you do more harm to the ordinary Joe
Blow scientists who are not burdened with the baggage of some particular line
that they need to publicise for the sake of their own prestige. We younger
`ordinary' scientists often don't have the secure and stable positions that our
older more illustrious colleagues do; we're the ones in the firing line. This,
as previously stated, is my only personal motive for having the energy to
engage in this discussion, futile though it is.
I have never placed the blame for the plight of Australian physics on your
shoulders. As spelled out in the
Ockham's Razor piece, that is a result of the feudal warlord
structure of our university politics which makes disciplines reliant on service
teaching (pure sciences) vulnerable when a government cuts overall funding.
Because your message is false it obviously cannot be the source of the problem.
However, your message does sway pople who don't know better, and who have an
interest in avoiding the real issues. We usually count on science journalists
as friends, not enemies, and people like you make our fight all the harder.
The use of the prestige of those you have interviewed as a
device for a
thesis that very few of them would agree to makes your message all the more
morally repugnant. But yes, I admit, many of my illustrious colleagues have
also employed dubious promotional tactics. You have just seen how easily it can
be done, and have had a go yourself. The very controversy you stir is probably
also a marketing device.
In contrast to the content of your book I detect little self-honesty in your
latest pronouncements. The only thing that came close were your parting remarks
to Robyn Williams on the "Science Show" that you would advise a young person
interested in science to read your book, get really angry, and endeavour to
prove you wrong. The only problem is that in today's anti-science climate it is
getting ever harder for young people to have the opportunities to get the
decent science education required to get them to that point.