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Freeman Dyson on the gas that we call life

If you can sacrifice 23 minutes, here is a fun interview with Freeman Dyson (who is 91 now)

Video: Conversations that matter - Earth is actually growing greener (Vancouver Sun)
They introduced Dyson as a monster mind. In fact, he is so smart that he was once in the same building with Albert Einstein, they say. ;-)

In 1981-2006, a quarter of a century, the Earth was mostly getting greener (green color on the map).

Dyson argues that CO2 has many direct and staggering consequences for the life on Earth that are more important than the indirect and questionable influences via the climate. For example, the 40% rise in CO2 since the Industrial Revolution meant about a 20% increase in the agricultural yields per unit area (in average: results vary). I like to use the same square-root formula.

And make no mistake about it, this is a big deal. If you use a naive estimate, you could expect that there would be 20% less food, and perhaps 20% of the world population (over a billion of people) could die of hunger if CO2 quickly returned to the preindustrial levels! Fortunately, the carbon dioxide won't drop quickly, and even if it did, the value 20% could be significantly lowered by better trade, redistribution, and transition to more efficient (although sometimes less tasteful) crops etc.

Dyson also says that the influence of CO2 on the climate is questionable and apparently unimportant. So the worries about the CO2's impact on the climate seem unjustified to him. But he doesn't understand the motivation behind this "religion" so he won't say that the people believing in this stuff are evil. Well, many of them surely are, I would personally say, but yes, in principle, many more may be honest.

Freeman Dyson knows the Japanese chap who was the first man who created a climate model with CO2. It had some positive climate sensitivity – still a lower one than what is popular today, despite the years of decreasing estimates. But Dyson thinks that we can't believe those predictions even if the climate models may be a good tool to explain the past observations. We may simply happen to incorporate a sufficient number of mechanisms and terms that may yield a good model of the past data; but this may still be "on the edge" and the future evolution may very well reveal and depend upon some aspects that were neglected in the past but will be important in the future.

Listeners also learn that Dyson spoke to Nir Shaviv who is just visiting Princeton. (Dyson clearly likes Shaviv a lot.) I knew that Nir was visiting Princeton because he (Nir) sent me an e-mail, also mentioning that he had a pretty fun conversation with Nima Arkani-Hamed etc. I hope that none of these insights is secret! ;-)

Despite its very formal atmosphere (and maybe partly because of it), Princeton is surely a place for creative, intelligent, non-ideological, bullying-free scientific conversations about important topics. After all, the number of prominent climate skeptics at Princeton is also rather high. Let me mention that climate skeptic Will Happer is a physics professor at Princeton, too. From this viewpoint, I would say that relatively to Princeton, Harvard is much more communist-party-like dictatorship with tons of ideology-driven pseudointellectuals and bullies such as Naomi Oreskes.

There is also a segment in the interview that is dedicated to the sunspots. Dyson says that the solar temperature is constant – well, the output varies by about 0.1% during the solar cycle, but it would give just a tenth or few tenths of a degree on Earth via the Stefan-Boltzmann law. And the total output doesn't seem to change much in the longer run (e.g. from 1600 to 2000 AD), either. But the sunspots influence the activity which may impact the terrestrial climate indirectly, and by higher percentages.

He mentions diverse and strengthening evidence in favor of cosmoclimatology while he says that the mechanisms – probably involving clouds and cosmic rays but we are not sure – remain less clear (Svensmark might dislike this comment). The interviewer Stuart McNish says that he did some research after watching An Inconvenient Truth and he was surprised that water vapor made... 90 percent of the greenhouse effect. How can you neglect it? Well, you can't, Dyson says. Why people became obsessed with CO2? Because it's a gas we emit and add.

Again, CO2 is so beneficial that it would be crazy to try to reduce it, Dyson tells us. Amen to that.

The interviewer tried to read the IPCC report and it seemed technically hard to me. But he was attracted by the comments about the temperature adjustments. Why are they being done, the host asks? Dyson, like your humble correspondent, answers that the adjustments are desirable because the temperature is a difficult thing and is affected by lots of local effects and details linked to the apparatuses that we want to eliminate when we're interested in some more objective or global information about the climate.

As an analogy, Dyson mentions that Keeling decided to measure CO2 in the Hawaii because it's far from the bulk of the human activity, so this contaminating influence drops away and the reliability of the measurement improves. To measure the global mean temperature, which is rather poorly defined, anyway, we have to measure at lots of places (Hawaii isn't enough for the global temperature) and deal with lots of confusing local distortions.

Dyson praises the weather forecasts and the role of computer models in the improvements – up to a week, the weather forecasts are doing well. The 10-year timescale hasn't been mastered, however (or 2 weeks from now, the interviewer quips). Benjamin Franklin was a pretty good weather forecaster because he was 1) more skillful than most others and 2) out in the open air which helps.

Almost none of us (perhaps with the exception of Dyson) will be around in 100 years from now so we can't know what will happen, the interviewer says. Dyson corrects him that we can be pretty sure of lots of things about the year 2115. He didn't mean the motion of the celestial bodies, however. Among the near certainties, Dyson said that we will keep on burning fossil fuels and the CO2 will keep on increasing. The world will be greener.

What will Dyson say to the people who want to share Dyson's optimism but who are cowards without balls and don't want to oppose the fashionable climate doomsday cult?

Dyson's answer is simple: Become Chinese or Indian. Those Asian nations aren't pessimistic at all – partly because they have seen lots of improvements recently. So the doom and gloom is largely confined to the academic environments, and pretty much only in the Western societies. The media have joined but the general public has lots more common sense. Dyson recommends "Cool It", a book by Bjorn Lomborg.

When the interviewer mentioned that both Lomborg and Willie Soon were vilified, Dyson says that one must enjoy being in the minority. By the way, do I or did I (when it comes to things like climate change among the scholarly folks)? Well, I would say that I could live with that by growing some special kind of pride. But when evaluated in total, I don't enjoy this status. I suffer when I see that most people are deluded about something. And they are deluded about so many things.

Dyson smiles and points out that fortunately, he doesn't have to be afraid of losing his job. ;-)

Is the climate orthodoxy incontrovertible? A top Canadian AGW activist is quoted as recommending to imprison all the climate skeptics. Dyson says that literally, the existence of man-made climate change is a fact. The other questions – which must be asked and must be asked separately – are how strong the effect is, and whether it's good or bad. When things are summed up, the change is small and good, Dyson concludes.

(That's what science says. In the real world of politics, the situation is different. For example, Barack Obama announced that he will fight against CO2 because he believes that this fight will cure his daughter's asthma whose worst episode was actually caused by the smells of a circus and the daughter has allergies. This individual isn't a rank-and-file shaman somewhere in Kenya; he is the president of the leading nation of the industrialized world. You can't make this thing up.)

Freeman Dyson remains optimistic about the world. It may be partly due to his growing up in the 1930s when the world was so much worse. We never expected to survive, he says. Crisis, Hitler, Second World War, threat of biological weapons, other bombs. Your optimism may depend on where you start.

Thank you.

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reader Alan_McIntire said...

That reference to Einstein reminded me of another story I read about Freeman Dyson. When he came to Princeton in 1947 he was dying to meet Einstein, so went to Einstein's secretary, Helen Dukas, to make an appointment. In order to have something relevant to discuss, he got copies of Einsetin's papers on unified field theory. Reading them that evening, Dyson decided the papers were crap. He couldn't face the great Einstein and tell him his papers were junk, so he said he cancelled the meeting and spent the next eight years avoiding Einsten .

reader David Brown said...

In connection with the supersymmetric bet, what might the new run of the LHC find? In a recent post, Matt Strassler contended that "... dark matter could easily be of a form that the LHC cannot produce, (for example, axions, or particles that interact only gravitationally, or non-particle-like objects) ..." What is the argument against the new run detecting axions?

reader etudiant said...

Is the CO2 abundance really a limiting factor on plant productivity? If memory serves, there are two metabolic pathways for plant photosynthesis, C3 and C4, where the latter is less CO2 limited.

The 20% increase in plant productivity relates to a projection by 2050 of 550 pp million of CO2 in the atmosphere, referenced here: .
Sadly the full paper is paywalled, but the C3 benefit potential from added CO2 is high according to the paper:
" In theory, at 25°C, an increase in [CO2] from the present-day value of 380 ppm to that of 550 ppm, projected for the year 2050, would increase C3 photosynthesis by 38% (9)"
Apart from these granularities, Dyson clearly has the perspective that is lacking in this discussion. Sadly, I fear that few of the AGW believers will ever be willing to hear him.

reader Tony said...

As for the clouds, they want more physics students:

reader Luboš Motl said...

Dear etudian, yes, C4 crops are much less affected by changed CO2 levels than C3 crops, see e.g.

for a sentence saying that. One may project to 2050 - like the paper above also does - but one may also evaluate the changes in the past and a similar change has occurred in the past, since the industrial revolution, too.

reader Luboš Motl said...

Dear Lino, it depends exactly what one does. The results of these measurements pictures are always dictated by the well-known basic laws of quantum mechanics. If the position is measured, the squared wave function |psi(x,y,z)|^2 determines the probability that the electron will be seen at a given point.

But be sure that

1) if you want to map the shape of |psi|^2, you have to repeat the same experiment many times

2) if you want to measure the position - or paint the orbital (when repetitions are used many times) - you have to use photons that give the electron so much energy that they kick it from the atom

3) the better resolution you want, the higher frequency of the photons you need, and the more you change/ionize the atom

4) some pictures of orbitals may look smoother because they're actually low-resolution images (the position and the wave function is blurred) which can be taken while making a smaller impact on the electron.

reader Poptech said...

Please don’t repeat unsubstantiated urban legends, as this nonsense is not supported anywhere online. Dyson respected Einstein and it was Einstein who did not communicate with the younger scientists at the institute.

reader Luboš Motl said...

Alan didn't say that Dyson didn't respect Einstein. He wrote that he figured out that Einstein's papers on unified field theory were not right or valuable - and indeed, they weren't, and he didn't want to tell him this cruel truth.

If you can't find a fact "online", it doesn't mean that it's wrong. Moreover, your claim that one can't find it online is rubbish. You can find it in the comment section of the world's most important physics blog, and it's upvoted many times. ;-)

reader Poptech said...

I cannot find a single reliable source for the comment, as blog comments are notoriously unreliable.

Alan claims to have a read a story about this so it should be easy for him to produce the source.

reader Luboš Motl said...

It could be easy. On Anthony Watts' blog,

Alan wrote the same story and said he found it online.

reader Poptech said...

Interesting that the whole relevant section is not quoted.

reader Luboš Motl said...

Why should it be "quoted"?

reader Poptech said...

I am going to verify this story.

reader Luboš Motl said...

Is there something in this innocent story that offends your religious sensibilities or why are you so obsessed by the efforts to question it?

I was reading Einstein's papers on unified field theory when I was 16, in German, in Pilsen's scientific library - shortly before communism fell. For some time, I liked them and believed that he had to have something important. But rather quickly, I realized they were extremely artificial and not deep. Various things such as a non-symmetric metric tensor, torsions added to the Christoffel symbols, and so on. All these attempts may be sold as natural extensions of GR but they are not because the "enhanced" objects are no longer irreducible. And one may see that these theories don't really agree with the desired equations (and experiments), too.

The only research direction on unified field theory that Einstein wrote papers about was the Kaluza-Klein theory - adding electromagnetism using extra dimensions. This is physically sound and important in modern physics.

If I came to Princeton's IAS at any point after I understood the problems with Einstein's papers, I may have behaved exactly in the way that Dyson did according to this story.

reader Poptech said...

I am not religious so it is not possible for me to be offended in such a way.

I question it, because I have ran across various "stories" like this before that have turned out to be false or misleading.

Either way I will verify it.

reader Luboš Motl said...

There have also been millions of criticisms and disagreements with the story that turned out to be misleading or downright incorrect.

reader br said...

I am still struggling with implications of how 'observers' work. For me as an 'observer A', it appears simple - I can make an observation, compare to QM and all is well. But as 'observer B' I am also ignorant of many things - others may have made observations that I don't know about, and that is fine too. But in that case, as I know there are other observers out there, I am sure there is a 'better' wavefunction that I don't know about, and which still makes sense to talk about as existing (in some mathematical sense, though not as a physical object). So following this as far as one can, would it be fair to say that there exists a 'best' wavefunction, that somehow the universe knows about (similar to a 'God's eye view'), but humans may or may not know about? In other words, the universal wavefunction is collapsing on a regular basis, with or without my knowledge? Can it make sense to talk about such a thing, even if I don't know what it is? I guess it doesn't make any functional difference to me, but it would still give a sense of reality which is 'out there' (not just dependent on me as an individual), and would be compatible with consciousness being somehow integral with the universe's existence (the pan-psychist type approach that you seemed sympathetic to recently).

reader Poptech said...

This is why I am verifying the story and not simply criticizing it.

reader Luboš Motl said...

There doesn't exist any "best wave function" in general because that would be a classical configuration. What you're proposing is *still* the very same classical physics. Hundreds of times. No, no, no. Change the words in 100 different ways but it will still be wrong.

Observers get some knowledge about the observables, deduce the relevant pure vector or density matrix from that, and make predictions from that. The more reliable and fine the measurement - the information they got - will be, the better the predictions will be. The word "better" may be expressed relatively to a better observer with better apparatuses making the initial and final measurements, but the measurements have to be actually done, otherwise the prediction exercise for the particular task can't be done.

An even more accurate observer may not measure this final outcome but only a later one, and he will inevitably describe the moment of the intermediate measurement via general superpositions.

The most accurate observer is one that makes no measurements at all.

reader john said...

This never-ending struggle made me sure it is best to internalize shut up and calculate approach as soon as possible. I think that point of view should be thought in physics 101 class.

reader br said...

I have no wish to go back to purely classical knowledge, so 'best' in this sense does not mean 'infinitely narrow spikes at all times', for example, or infinitely fine measurements. Limitations of QM still apply. I'm trying to tease out if anything can follow from a pan-psychist view, and considering what is an observer anyway - if consciousness is not just of human beings, but is a universal property, which it seems you would agree from your recent posts. 'Best' in this sense is to stitch together all the best knowledge into some 'universal knowledge' - observer A has better information than observer B on what happens inside the box, so one could stitch together that part with some of B's knowledge of what is going on outside the box (that A can't see). Observer C might be a dog down the road, D an insect and E a photodetector. QM would apply to all the multiple observers, but as you seem sympathetic to pan-psychism, what is your view on a hypothetical 'universal observer'?

reader Leo Vuyk said...

David Bohm tried to deepen the
Quantum Mechanics of that time. IMHO, an adapted instant Broglie- Bohm Pilot Wave, could still
be the Origin of all wavefunction collapses in our Universe as related through the big bang to our opposing anti-copy Universes.

Then every wavefunction collapse is the result of the uncertainty which of the rolling entangled (anti-) copy dice (quanta) has made the first choice (collapse) and influences instantly all other (anti-copy) quanta at long distance.

reader Gordon said...

Hmm, I wouldn't call Sm*lin and Dyson "colleagues"...that distorts the meaning of the word too much :)

reader Luboš Motl said...

BR, you surely *are* proposing to return to classical physics.

Classical physics doesn't mean that there are infinitely narrow spikes. Classical physics means that there is a God's eye view - some universal, objective information about the system (which takes values in a set of possibilities - which we usually call the phase space) - that evolves in time according to some laws, usually deterministic ones.

Maxwell's theory is a completely classical theory and it admits no infinitely narrow spikes. What you propose about "your meaning of psi" would be just a tiny variation of the electromagnetic field. It would be a classical field.

Nature isn't described by any classical field in this sense. Can you please try to understand this very simple sentence?

reader Rehbock said...

Wonderful post. I think that br should read your earlier posts and will get it. I really liked your point that the most accurate observer makes no measurement at all. You must be channeling Feynman on that.

reader RAF III said...


reader Luboš Motl said...

Thanks, Rehbock!

One could probably construct some catchy fairy-tale about this point. For example, God is the ultimate non-interventionist or pacifist if not a hippie. He only wants to know things exactly, so He never touches anything, and He therefore knows all the probability amplitudes accurately but not what happened.

reader Liam said...

So from Gods' perspective, omniscience and omnipotence don't commute... :-)

reader Tony said...

Technically, you are speaking about omnipotence modulo commutators, i.e. about a certain omnipotence equivalence class. The real omnipotence is the entire set.

reader Leo Vuyk said...

It sounds weird, but as a consequence I would suggest, that the Big Bang did not produce instantly all the Fermions in the universes. Even now there is reason to assume that lots of Fermions are produced- in the form of charged plasma-globules by all BHs (see ball lightning fig B.) even by the largest primordial Big bang splinters located outside large galaxies.