
Scientific method: Defend the integrity of physics - noobermin
http://www.nature.com/news/scientific-method-defend-the-integrity-of-physics-1.16535
======
ssivark
Johannes Koelman takes apart that claim in a concisely articulated argument --
[http://www.science20.com/the_hammock_physicist/falsifiabilit...](http://www.science20.com/the_hammock_physicist/falsifiability_and_the_integrity_of_physics-151714)

TL;DR: _" The scientific method is not about testability or falsifiability per
se. It is about trying hard to falsify. Nothing more, nothing less. Truth is
to be found in those ideas that survive despite the multitude of attempts to
falsify them[...]quantum gravity theories needs to reproduce all known low-
energy physics, as well as all known classical gravitational phenomena. In
other words: if you ensure your favorite theory of quantum gravity in the
appropriate limits reduces to the standard model and Einstein's theory of
gravity, your theory has survived all falsification attempts ever undertaken
in the history of physics. This is a key point that fails to receive attention
in 'string theory and falsifiability' debates."_

~~~
hga
Let me put on my reductionist hat: what use would be such a theory, if it
perfectly matches observed reality but offers absolutely nothing new?

String theory has often been called mental mstrbtn (evidently using the real
world hellbans such comments); should anyone get paid for pleasuring their
minds in this way???

~~~
manicdee
"Intellectual onanism" is a more sophisticated way ofsaying the same thing
without triggering the bad word police.

~~~
hga
Without, though, the wonderful alliteration.

Thanks, the modern word isn't part of my working vocabulary.

~~~
CGamesPlay
Apparently not a modern word; biblical:
[http://biblehub.com/genesis/38-9.htm](http://biblehub.com/genesis/38-9.htm)

~~~
hga
That's the etymology, but from what I looked up it wasn't used as such until
the 16th Century.

------
viggity
"I take the hard view that science involves the creation of testable
hypotheses" \- Michael Crichton

Consensus is not science. Computer Models are not science. Elegant equations
are not science. Science is science. Science is testable, repeatable,
falsifiable.

[http://www.wsj.com/articles/SB122603134258207975](http://www.wsj.com/articles/SB122603134258207975)

~~~
pavlov
So virology is not science? The belief that HIV causes AIDS is based on
consensus. (Not everybody agrees even today, but the scientific community has
moved on.)

Protein folding is not science? Its modern study is based on computational
simulations.

Not all sciences are like physics. It's strange that the author of _Jurassic
Park_ would speak up against consensus and models when they're so fundamental
to paleontology, for instance. Should we not believe that dinosaurs existed
because evidence of their existence is not a falsifiable theory?

~~~
pistle
You can't smear virology because of HIV. Then again, NIH speaks directly to
Koch's. See here:
[http://www.niaid.nih.gov/topics/HIVAIDS/Understanding/howHIV...](http://www.niaid.nih.gov/topics/HIVAIDS/Understanding/howHIVCausesAIDS/Pages/HIVcausesAIDS.aspx)

You can't smear protein folding because of a modern method of study. Are you
arguing that you think it's possible that proteins don't fold or that some
specific example of a protein might be folded differently than certain
simulation experiments postulate?

You can't smear the fossil record because people put feathers on different
species all the time. Fossils exist and organisms existed which created them.

There is science in each area. testable, repeatable, falsifiable. In
theoretical physics, the argument is far more salient. There is a wack wing
doing something that's not science (per the 3 tests definition) and that wing
is trying to argue that the 3 tests shouldn't apply so they can continue to
get funding.

Most physics in and/or past high school will gladly tell you that the Bohr
model for atoms is a klunky model that gets the uninitiated into grasping a
modestly functional model.

Stringnuts seem to be raising their klunky model up and trying to say it gets
to be a theory in a way which makes science and scientists (3 tests style)
seem no better than charlatans and preachers. Part of me thinks this is
because most of what seemed should be evident from ST is not panning out and
they know that they are too far down a path. If ST gets funding cuts, their
CVs atomize and blow away with the wind. They get to teach basic physics for
kids meeting core requirements and polish mirrors in someone else's lab.

When they are getting to close to the corner they backed themselves into, they
try to argue that Bayesian analysis says it is highly unlikely that the corner
exists.

------
jordanpg
What is the utility of advancing a theory that is unfalsifiable in the
Popperian sense? This category of theory, even if on strong philosophical
footing, seems to be quite apart from theories that can be used to build
devices that won't work if the theory turns out to be wrong.

In any case, I doubt very seriously that there are more than a few thousand
people alive who can have an informed opinion on this.

~~~
eternalban
> What is the utility of advancing a theory that is unfalsifiable in the
> Popperian sense?

Conceptual clarity in context of our uncanny existence?

~~~
hga
To quote from the article: " _As we see it, theoretical physics risks becoming
a no-man 's-land between mathematics, physics and philosophy that does not
truly meet the requirements of any._"

What I think you're suggesting is a philosophical benefit. Which echoing
another comment of mine, probably shouldn't get funded by the NSF (the US
National Science Foundation, one of the parts of the US Federal government
who's remit includes funding theoretical physics).

~~~
toufka
I wouldn't go that far - there's still utility to be had in generating the
theories.

What is a practical problem though, is that other less sexy fields of physics
are losing funding to the string theorists. Give them their own discipline,
their own pot of cash and let them figure out their theories - while
_simultaneously_ maintaining a separate pot of cash for those who work on the
falsifiable parts of physics.

In other words, let it be a no-man's land, so long as it's boundaries are
delineated and separate from the math, physics and philosophy that it came
from. There's nothing wrong with designing a new discipline.

~~~
hga
Yeah, one of the other big issues that I've noted people in the field
complaining about is how string theorists are indeed sucking up a
disproportionate share of theoretical physics, but worse than that. Since
their's is, from what I read, the US consensus on how to do that area of
theoretical physics, in the usual group think fashion of funding
organizations, other approaches find difficulty getting _any_ respect, let
alone funding.

Anyway, the problem here of course is that they would never accept being
relegated to a field that's not "physics", since capital P Physics has so much
respectability, pretty much the most of anything. But since they're now openly
trying to redefine scientific truth (as the FDA did to come up with its second
hand smoke "science"), it's hard to see any option less severe than the one
you propose.

------
hga
" _The issue of testability has been lurking for a decade._ "

I guess he means it's become too big to ignore, for one of the things I
remember about string theory when I first learned of it in the mid-late '80s
was that at that time the string theorists couldn't conceive of a way to test
it.

------
jostmey
Relevant quote from the last line of the article: "The imprimatur of science
should be awarded only to a theory that is testable. Only then can we defend
science from attack."

~~~
hga
Pity that's entirely negated by the authors' defense of "climate change", for
changing the last word from cooling (when I was growing up) to warming, to
finally "change", following of course short term temperature patterns,
unambiguously signaled that the field of climate "science" had become
untestable.

(Evolution, on the other hand, is sort of testable, in for example molecular
genetics. Weasel words because the biggest argument is metaphysical, or as I
poise it, "Who are we to say how God created the earth?" I'm agnostic, but as
someone put it in a discussion I just read, not very good at it. :-)

~~~
darkmighty
"Cooling", "Warming" and "Change" are one about as vague as the other. You're
oversimplifying it, if you want a rigorous overview by what is meant by
climate change go read IPCC's reports introduction: the major impacts of rapid
man-made disturbances on the global climate. Some word had to be used instead
of "Let's discuss Major Impacts of Rapid Man-made Disturbances on The Global
Climate". (Ill stop derailing the discussion here)

~~~
hga
" _We have always been at war with Eastasia._ "

Review my comment, particularly the " _when I was growing up_ " bit. If my
account oversimplifies, that's only because I'm repeating what the received
wisdom was during each period as the "scientific consensus" changed to match
the short term temperature record, and that filtered into the culture.

I was born in 1960, when Eisenhower was still President. It was the Official
Truth, e.g. in the science fiction of the period (e.g.
[https://en.wikipedia.org/wiki/Time_of_the_Great_Freeze](https://en.wikipedia.org/wiki/Time_of_the_Great_Freeze)),
that man was bringing on a new ice age.

 _I remember_ when the Party Line changed to "global warming". And I of course
remember when that became untenable and changed to "climate change". And I
read some of the scientific literature for each stage, I knew by the end of
1st grade that my calling was to be a scientist.

You may prefer to get your received wisdom from entities that make full use of
modern style versions of _Nineteen Eighty Four_ memory holes, I'll stick with
what I personally witnessed and now remember.

~~~
phaemon
> And I of course remember when that became untenable and changed to "climate
> change".

Really? When did that happen? What year?

~~~
hga
Why should I be called upon to remember exactly which year ... for that
matter, this is not the sort of thing that can generally be pinned down to one
year, although it's possible it was that fast. Fashions can change rather
rapidly.

But let's focus on the meat of my argument here: do you deny that the big
thing use to be "global warming?", in the '80s and '90s? If not, this article
is evidence that it's now "climate change".

But to partly answer your question, even the massaged global temperature data
stopped showing warming ~15 years ago. For a while, of course, nobody thought
much of it, a year or three's pause means nothing. Hmmm, maybe it was around
10 years into that? It did take a while for the short term trend to become
evident, then after taking enough flack on that....

~~~
phaemon
> Why should I be called upon to remember exactly which year

Your own words were: "I of course remember when that became untenable". I
didn't think it would be any effort.

> Hmmm, maybe it was around 10 years into that?

So about 5 years ago then? 2009 or so. Let's say after 2000 just to be safe.

Because the IPCC - you know, the Intergovernmental Panel on Climate Change -
was formed in 1988. That's "Climate Change". In 1988. I think perhaps your
memory is faulty.

Also, "global temperature data stopped showing warming ~15 years ago" is just
wrong. I thought you said you were a scientist?

~~~
hga
As waterlesscloud notes, I'm talking about the popular use. I'll turn around
your IPCC argument: anyone with a clue would realize there was a distinct
chance another change in the party line like the cooling to warming flip would
be required by the short term temperature record, so the IPCC merely future
proofed their gravy train.

My _calling_ was science. Finances prevented me from fulfilling that
potential, which is why you'll find me here in Hacker News.

Saying "just wrong" is no more convincing than my bald assertion of what I
thought was generally accepted, so for example use a search like this one:
[https://www.google.com/search?q=global+warming+stopped](https://www.google.com/search?q=global+warming+stopped)
to find deniers like the BBC, Wikipedia, _NATURE_
([http://www.nature.com/news/climate-change-the-case-of-the-
mi...](http://www.nature.com/news/climate-change-the-case-of-the-missing-
heat-1.14525)), National Geographic, and The Economist in the first two pages
of my results....

~~~
yongjik
Well, let's try with literally the first Google hit for "global temperature
graph":
[http://data.giss.nasa.gov/gistemp/graphs_v3/](http://data.giss.nasa.gov/gistemp/graphs_v3/)

The first graph shows that temperature for 1998 (I think) is very high
(~0.6C), and indeed temperatures in this century centers around this value.
Has global warming stopped since 1998?

But wait, one quickly discovers that the temperature for 1998 was the
_highest_ among all years up to 1998. Not only that, it is ~0.2C higher than
1997, which was also higher than all previous years. In fact, 1998 is >0.4C
higher than the coolest year in the 1990s.

It doesn't take a lot of statistical expertise to conclude that 1998 was in
fact an anomalously hot year, _if one were to look at data only up to that
year_.

In this century, we hover around this 1998 temperature, and even routinely
exceed them. What was an outlier became the normal.

Soon the same temperature will be considered a cool year. (Of course, the
graph doesn't _say_ that, but thousands of very bright people who spent their
lifetime studying these graph say that. I have no reason to doubt them, when
the best argument thrown against them is "if you compare the hottest year of
the last century with today's average, they are the same!")

------
swatow
If a theory is _mathematically_ elegant, I would consider that evidence for
the theory. For example, the ability to explain the exact gauge groups and
representations that comprise the Standard Model, or the masses of the
elementary particles. In fact, I would say that a theory that could do this
would be "tested" because it is a historical accident that we discovered the
gauge groups/masses before the theory.

As far as I understand it, string theory once promised to do precisely this.
String theory was considered promising because it had no vertex factors in its
Feynman diagram. Because there were only strings, you only needed to know the
free space propagator for a patch of string. However, as I understand it,
string theory then turned out to be have more possible parameters, and this
original promise was lost.

The kind of elegance that the author seems to be talking about is conceptual
elegance, and I also reject this as evidence. For example, invoking the
anthropic principal plus multiple universes to explain the parameters of the
Standard Model. To me this is no more compelling than the Christian "grand
unified theory" that unifies ethics, numinous awe, and the existence of the
universe.

------
Xcelerate
To me, science is the nature of prediction. How well do your predictions match
reality? Predictions are made on the basis of some kind of model (a set of
equations is an example of one such model). The quality of science then, is
predicated upon how closely predictions made via a model match reality.

In this sense, physics is the "best" science currently (12 decimal places of
accuracy in predicting the gyromagnetic ratio of an isolated electron),
followed probably by chemistry, then biology, then medicine, then psychology,
etc. The only thing I mean by this ranking is that it is harder to come up
with models that give accurate predictions in some fields relative to others.

A few people on this page have stated "Computer models are not science."

I disagree with this. My work is in molecular dynamics simulations and quantum
chemistry.

Consider an experiment: you test nature and try to derive some sort of model
that allows you to make future predictions. However, your model is marred by
the concept of experimental error and system complexity (for instance, we
can't currently observe all the neural activity in the human brain because of
how difficult it is to image a brain without being too invasive).

Now consider a simulation: you take pre-existing models and use them to
formulate predictions.

Both experiment and simulation allow you to make predictions that can be
tested experimentally. But the quality of your predictions depends only on how
accurate your model is, not the mere fact that you are running a simulation!

Let me elaborate: quantum mechanics is almost perfectly accurate in describing
all phenomena that occur in everyday life (Peter Gill has said this, and I
believe Dirac said it as well). It only falls apart with things like quantum
gravity.

So we have a _very_ accurate model. If you plug the wavefunction of a
particular human brain into the Schrodinger equation, you'll get an almost
perfect evolution of the brain through time (as compared experimentally to the
real brain). The problem is that despite having a _very_ accurate model of
reality, it is not easy at all to turn this model into a testable prediction.
We can really only use this model to its fullest capability for a couple of
particles.

And this is where computational modeling comes into play. You can take this
highly accurate model of reality called quantum mechanics and intentionally
introduce error into it in order to speed up the rate at which you can
formulate a prediction from it, e.g., you make an approximation to the
Schrodinger equation that you can solve quickly, and while you know that this
approximation is not an exact solution, you can still develop predictions from
it. And when you take these predictions and then test them experimentally, you
find that the experimental results match up pretty well. In fact, in some
cases the error in your approximation to the Schrodinger equation is small
enough that you can do _better_ than experiment, because your numerical error
is smaller than the systematic error that an experimentalist must deal with in
the lab.

So to me, it doesn't matter where the prediction comes from, or how it was
formed. If that prediction can be tested -- and if once tested it is found to
match reality to some degree -- then you have some form of science (of varying
levels of quality).

String theory does in fact make physical predictions. But those predictions
can't be tested _yet_. So it's still a form of science, although maybe not a
very useful form since it could be a long time (or never) before we are able
to test it somehow. Many-world theory however is NOT a form of science,
because it makes NO predictions whatsoever. It's just an interpretation. It
says nothing different than any other interpretation of quantum mechanics. It
is not science. (In a similar vein, I've always thought people who try to
"use" science to argue for or against the existence of God are totally wasting
their time since neither side can even come up with a testable prediction.)

------
kijin
Why so impatient?

The Earth goes around the Sun, not the other way around. Copernicus realized
this for the first time in the early 16th century. By the end of the 17th
century, almost every scientist in Europe were convinced that Copernicus was
right. Why? It was elegant (no epicycles) [1], it was politically exciting (it
went against the doctrine of the Roman Catholic Church and was therefore
especially attrative to reformers), and some of its followers (ever heard of
Isaac Newton?) had come up with really cool ideas.

In other words, heliocentrism in the late 17th century had all the features
that a popular programming language today might have [2]. But as a scientific
theory, it remained unconfirmed, and its rival (geocentrism) remained
unfalsified, even as the world embraced heliocentrism as the One True Theory.

Conclusive falsification of geocentrism, and thus compelling confirmation of
heliocentrism, only arrived in 1838 with the first observation of parallax.
That was almost 300 years after Copernicus first advocated heliocentrism, and
over 100 years after almost everyone accepted it. For all those decades and
centuries, people had been believing in heliocentrism without having tested
it.

The history of science is rife with examples like this. Some theories are
inherently difficult to test, so it can take a few decades, or even centuries,
to collect conclusive experimental evidence. Sometimes you have to wait for
others to develop the technology you need, just as heliocentrism had to wait
for highly accurate telescopes to measure parallax. Because it costs a lot to
develop such technologies, a theory without a critical mass of highly
motivated followers is at risk of fizzling out before it can ever be tested.

This is an inevitable consequence of the fact that science depends on a bunch
of hairless bipedal monkeys for its existence. When falsification takes a long
time, humans tend to be influenced by political, philosophical, aesthetic, and
even religious factors. And this isn't a Totally Evil Thing™, because if we
weren't influenced by such factors, much fewer theories would ever make it to
falsification. They would just fizzle out for lack of motivation.

How long has string theory been around? 50 years? And we're already being
impatient with it? Remember how long we had to wait for Darwin's theory of
evolution to become mainstream and well-supported by evidence? Remember how
long it took for "driftists" (those who supported plate tectonics) and
"fixists" (those who opposed it) to reach a consensus? 50 years is about as
long as it takes to test a theory about the distant history of this planet
using recent technology. How much longer do you think it will take to test a
theory about the fundamental structure of the universe, when we can't even
imagine the kind of technology we'd need in order to start testin'?

Copernicus waited 300 years. String theorists should expect to wait 500-1000
years, if not more. And we, the rest of the society, should strive to support
such long-term endeavors to the best of our abilities [3]. It's not as if
string theorists are asking us to build expensive underground facilities for
them, right?

[1] The lack of epicycles was a particularly attractive feature because of the
newly discovered moons of Jupiter. Too many levels of epicycles made the
Ptolemaic model look rather inelegant.

[2] Elegant syntax, sexy community, and a cool standard library.

[3] That is, unless there's something so obviously fishy about a theory that
the consensus is that it's not even worth trying to falsify. Intelligent
design probably falls into this category.

~~~
vacri
_Copernicus realized this for the first time in the early 16th century._

Copernicus came up with the predictive mathematical model, but the idea of
heliocentrism goes back almost two millenia before him.

 _The history of science is rife with examples like this._

The collection of ideas now known as 'the scientific method' didn't exist in
Copernicus's day, and was still having major modifications over the past 100
years. At this point, we've really nailed down something that was barely a
wisp of an idea in Copernicus's time. It took a long time simply because
falsifiability wasn't an ingrained scientific process in the age of
Copernicus.

 _And we, the rest of the society, should strive to support such long-term
endeavors to the best of our abilities_

500-year experiments should be very low on the list, particularly ones to be
supported 'to the best of our abilities'. We have more pressing issues and
ideas that should get more of our attention. Saying 'trust us, this will be
important long, long into the future' isn't too far from founding a new
religion.

~~~
kijin
> _At this point, we 've really nailed down_

Have we really nailed it down?

Except within a certain faction of purists who want to purge science of
anything that cannot be falsified in the short term, and outside of textbooks
influenced by their opinions, I don't see any consensus on what constitutes
_the_ scientific method and what falls outside of it. How do we know that
there won't be further "major modifications" over the next 100 years?

Modern people often suffer the illusion that they exist at the apex of
history, and their proud claims of perfection just as often fail to stand the
test of time.

> _It took a long time simply because falsifiability wasn 't an ingrained
> scientific process in the age of Copernicus._

No, it took a long time because the technology needed to falsify geocentrism
simply did not exist until the mid-19th century. Likewise, we currently do not
have the technology to test large parts of contemporary theoretical physics.
In fact, it seems to be in the very nature of theoretical physics that its
predictions are hard to test. I can't think of a single major advance in
modern physics that took less than a decade to test conclusively.

> _500-year experiments should be very low on the list_

I agree. But when it comes to highly abstract theories of cosmology, do we
really need to compile a list of priorities at all? It's not as if string
theorists and multiverse proponents are asking for funding to send probes to
outer space. It's all armchair speculation at this point, and nobody's forcing
anyone to believe anything.

If we as a society can afford to throw money at SF films and number-puzzle
games with a high "geek factor", surely we can afford to let some professors
engage in geeky speculation for a few more centuries? Because that's all I
mean by "support to the best of our abilities". Just keep respecting them as
fellow scientists whose conjectures unfortunately cannot be tested within
their lifetime. Acknowledge that a small fraction of our scientific workforce
needs to be engaged in such long-term projects, and take comfort in the fact
that this fraction will always remain small.

Or have we become so insecure, narrow-minded, and obsessed with short-term
ROI's that we cannot stand the sight of as-yet-unfalsified theories occupying
the precious pages of our journals?

