
Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics - gnosis
http://discovermagazine.com/2009/sep/06-discover-interview-roger-penrose-says-physics-is-wrong-string-theory-quantum-mechanics
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carpdiem
I think this post title is misleading.

Roger Penrose is not merely saying that quantum mechanics is wrong. Instead it
would be more fair to say that he views quantum mechanics as an incomplete
theory, and one that should be continually challenged.

It's like Newtonian mechanics. Newtonian mechanics is correct, within its
domain (for velocities much less than the speed of light). No one argues with
the predictions of Newtonian mechanics within their domain. Einstein's
achievement with special relativity, then, wasn't showing that Newtonian
mechanics was wrong; instead, he just showed the world the true extent of its
domain, and developed a theory (special relativity) that generalized Newtonian
mechanics to a larger domain (velocities less than the speed of light). It's
terribly unfair to Newtonian mechanics to call it 'wrong' in the same way that
the statement 2+2=5 is 'wrong'.

Similarly, the fantastic experimental success of quantum mechanics ensures
that it would be unfair to call quantum mechanics 'wrong'. Incomplete?
Certainly. Worthy of being challenged? Absolutely. Is it taken as gospel by
too many physicists? Probably. But is quantum mechanics _wrong_? No, decades
of successful experiments, and practically the entire modern electronics
industry, would disagree with that sentiment. The problem is that we just
don't know where the domain of quantum mechanics ends, nor the more general
theory that will take its place.

~~~
mjtokelly
What you say is well-put, but to nitpick the last paragraph: the limits of
quantum mechanics are well-established. QM is a special case of quantum
electrodynamics, which is a low-energy special case of the Grand Unified
Theory.

<http://en.wikipedia.org/wiki/Quantum_electrodynamics>
<http://en.wikipedia.org/wiki/Unified_Field_Theory>

While the latter is not fully fleshed out, its uncertainty only begins in
circumstances far weirder than what gives Roger Penrose pause.

Penrose says that "The [QM] equation should describe the world in a completely
deterministic way, but it doesn’t." But work such as Bell's theorem shows that
no deterministic equation could _ever_ be consistent with quantum mechanics:

<http://en.wikipedia.org/wiki/Bells_theorem>

~~~
Luc
> But work such as Bell's theorem shows that no deterministic equation could
> ever be consistent with quantum mechanics:

This isn't quite right, because you left out the word 'local' - see
<http://en.wikipedia.org/wiki/Bohm_interpretation>

Bell's theorem applies only to _local_ hidden variables.

~~~
mjtokelly
Right, but non-local determinism is difficult to square with general
relativity.

~~~
Luc
Indeterministic laws and the non-existence of particle positions and
trajectories are difficult to square with general relativity too - and Bohm's
interpretation doesn't 'suffer' those problems, while it predicts the exact
same observations. (Though I should say this is way out of my amateur-
physicist league - I'm taking my cue from 'Quantum Mechanics: Historical
Contingency and the Copenhagen Hegemony' [http://www.amazon.com/Quantum-
Mechanics-Historical-Contingen...](http://www.amazon.com/Quantum-Mechanics-
Historical-Contingency-Foundations/dp/0226132048) ).

------
btilly
Penrose contributed a lot and I don't want to minimize that. However when he
stepped outside of his own domain he makes some serious basic mistakes that
make him ignorable.

As an example in _The Emperor's New Mind_ he makes a number of claims about
consequences of Gödel's theorem for human thought that were flat out wrong. I
remember reading criticism of it from a logician in the mid-90s, and Penrose's
response. While I'm no logician, I know enough about it to know that the
logician was right and Penrose was wrong. Human thinking is known to accept
inconsistencies and so you can't apply Gödel's theorem to derive any
interesting conclusions.

When he moves from logic to physics he is even more out of his depth. Given
his verifiable mistakes in logic, I am comfortable in concluding that his
startling assertions about physics are far more likely to arise from further
mistakes of his than from his having found serious reasons to question the
foundations of modern physics.

~~~
anatoly
I agree with your description of Penrose's Goedelian claims (the logician was
Solomon Feferman), but I'm not sure why you say he'd be even more out of his
depth in physics. Penrose is primarily a mathematical physicist, not a
mathematican.

~~~
btilly
You are right. I had known his mathematical work, but didn't know his
biography.

That said, his physics work seems to have been in general relativity, not
quantum mechanics. Given what I know about how he messed up when he stepped
out of his area in math, I find it more likely that he has made similar types
of mistakes in quantum mechanics than that he has truly demonstrated that
mainstream physics is wrong.

~~~
slackenerny
_not quantum mechanics_

Except the twistor formalism he created (following ideas of no one else but
Dirac) is important branch of research in quantum mathematical physics and
string theory, not only classical gravity.

Just like Hawking or Freeman Dyson had, Penrose too earned his right to odd,
and even braggart opinions on everything. Especially since opinions are by
definition not meant to advance knowledge, or demonstrate results, but to
provoke and inspire discussion.

~~~
btilly
I think Fred Hoyle is a more appropriate comparison. Both did great work that
will last in the history books. Both held controversial opinions that were
marginalized by the broader research community.

~~~
slackenerny
Since Dyson contributed half of quantum electrodynamics, and we have numerous
Dyson theorems; and since Penrose contributed half of present classical
gravity, and we have numerous Penrose theorems, including celebrated Penrose-
Hawking incompletness theorem; I think Fred Hole, whose lasting contributions
beyond narrating popular books I do not recall, is a fine comparison to
Penrose as a pop writer, in addition to mine, perfectly deserved one to
scientists of certain calibre who also happen to have some unsubstained and
marginalized indiscrete opinions.

~~~
btilly
Among other things Fred Hoyle (at least learn to spell his name!) was the H in
the classic B2FH paper that elucidated the processes by which various elements
were created in stars, and explained the relative distribution of different
isotopes in the universe.

In my opinion that paper is on the list of the 10 most important discoveries
in science in the last century. See
[http://bentilly.blogspot.com/2009/09/what-makes-it-
science.h...](http://bentilly.blogspot.com/2009/09/what-makes-it-science.html)
for the rest of that list.

~~~
slackenerny
_at least learn to spell his name!_

Thank you for this most kind and substantial observation. In my defense, Hoyle
used to joke of himself like that since concieving his steady-state cosmology
where matter constantly flowed out of a "hole"; his autobiography "Home is
Where Wind Blows" is also a good read.

 _In my opinion that paper is on the list of the 10 most important discoveries
in science_

Took cosmology course (with very distinguished cosmologist) and heard of that
in passing. Since then forgotten, sorry (It was that important to me, maybe as
a footnote to the αβγ mechanism. Of course this says more about my ignorance
than importance of Hoyle's legacy).

So then, I view Hoyle as a crank out of my ignorance, you view Penrose as a
crank out of your apparent ignorance. Further discussion would not be a
rational argument.

------
teeja
[http://mindbody.blogspot.com/2009/10/penrose-kind-o-gets-
it....](http://mindbody.blogspot.com/2009/10/penrose-kind-o-gets-it.html)

"Schrödinger, Einstein, and Paul Dirac. They were all quantum skeptics in a
sense. Dirac is the one whom people find most surprising, because he set up
the whole foundation, the general framework of quantum mechanics. People think
of him as this hard-liner, but he was very cautious in what he said. When he
was asked, 'What’s the answer to the measurement problem?' his response was,
'Quantum mechanics is a provisional theory. Why should I look for an answer in
quantum mechanics?'"

[http://www.afterourtime.com/wiki/index.php?title=Quantum_Gra...](http://www.afterourtime.com/wiki/index.php?title=Quantum_Gravity)

~~~
nopinsight
In a way, a wise creator of a theory should be the one least fixated by it, as
he knows all its potential weaknesses inside-out and the messy way it came
into being. From your description, Dirac seems to be one of those wise
geniuses.

~~~
teeja
I'm sure you're right. Plus, in the sciences, he knows how his colleagues
minds work (and all the politics). Dirac probably kept mostly quiet about his
doubts because Bohr, the Godfather of QM, thought QM was the Cat's Meow, which
Schrodinger didn't. And Schrodinger _knew_ that he pulled his famous equation
out of a hat (not derived).

Likewise with Feynman, who always repeated "nobody understands quantum
mechanics."

Too, because of the _very_ competitive culture in the hard sciences, you don't
talk about things that are poorly understood. Because if you make a mistake,
you'll catch a lot of (friendly or unfriendly) ribbing later.

------
thisrod
I'd love to hear why Penrose really thinks the Everett interpretation is
crazy. He gives a very weak reason in the interview. No doubt he accepts the
atomic theory of matter, despite his inability to see atoms, so his inability
to see superpositions should not prevent him from accepting quantum mechanics.
It would be interesting to hear him address that.

~~~
Daniel_Newby
But you can measure atoms indirectly. I have not heard of a many-worlds theory
that is measurable even in principle.

~~~
thisrod
In principle, you could demonstrate superposition states of cats the same way
you'd demonstrate them for atoms or photons: return the live and dead cats to
the same state, and look for interference fringes. There are two difficult
parts. First, you have to kill the cat, rescusitate it, and restore every
molecule of its body to the original orbital, without leaving even one photon
of evidence. Once you've done that, it's a simple matter of getting the cat to
sit still while you measure its position within a tiny fraction of the
diameter of an atomic nucleus.

I found a fascinating history of the atomic theory at
<http://www.aare.edu.au/02pap/har02049.htm>, in the section titled "The
History of the Particle Theory". Atoms were once as fantastic as superposition
states are today, then they gradually became real.

The same page points out that the plausibility of atoms is largely a fluke.
People imagine that solid gold has the color of a gold atom, and gas pressure
comes from squeezing the atoms together. Quantum theory doesn't lend itself to
such simple but wrong explanations.

------
BRadmin
"In my view the conscious brain does not act according to classical physics.
It doesn’t even act according to conventional quantum mechanics. It acts
according to a theory we don’t yet have."

Do most modern AI researchers disagree with this?

~~~
lkozma
Yes, most modern AI researchers believe that the functioning of the brain can
be explained by electromagnetic and chemical phenomena, accurately described
by 1900s theories. The fact that we don't fully understand its workings is due
to its organizational complexity.

Penrose's arguments are discussed for example here:
<http://www.scottaaronson.com/democritus/lec10.5.html>

~~~
10ren
It's funny, but to be _certain_ that consciousness can be explained by _known_
laws - we just don't know exactly how - itself requires faith and is quite
unscientific.

Although I too _believe_ it.

~~~
lkozma
I see this just as an application of Occam's razor. What Penrose does has been
called the "law of minimization of mystery": consciousness is misterious,
quantum mechanics is misterious, so why not try to explain one with the other.

------
Ixiaus
Modern day science is built upon a mosh pit of physical theories that don't
all fit together well.

The number one premise failing physical theory today, is the concept of a
stationary container (the Universe) within which "matter" interacts.
Traditional physical theory states that the Universe is one of _matter_ ,
which is oh so limiting. Another hallmark of popular physical theory is much
of it's theories are based on empirical findings rather than a set of purely
theoretical postulates... Physical theory today is _a posteriori_ rather than
_a priori_ and using scientific experimentation to verify the theoretical
deductions.

Consider, for a moment, that the primary component of the Universe is not
matter, but _motion_. Discard the idea that there is a static natural
reference system (or stage) upon which things can be measured (you can tell
actors are moving on the stage because the stage doesn't move).

Instead of there being three dimensions with a fourth dimension added for
time; there are three dimensions of both space and time (time being a
_reciprocal_ of space).

Also consider, in this system, that there can be motion without anything
moving. If the primary component of the Universe is motion, then material
objects are a compound aggregate of motion; motion is, therefore, the
antecedent to matter.

For more, look here: <http://www.reciprocalsystem.com/nbm/nbm02.htm>

------
Estragon
To be specific, he's saying that the Copenhagen interpretation of QM is wrong.
I'm inclined to agree.

