Posted by
Rob on Wednesday, April 15, 2009 5:24:44 PM
Two months ago, I
blogged on Michael Brooks quitting his job at New Scientist and writing his "
13 biggest scientific mysteries", which have been suppressed by the science establishment. This has generated a flurry of reviews, and now the
New Scientist finally carries their review (though it might also be an abstract written by Brooks, I can't tell.) In any case, the list of items is now different.
For reference here is the table of contents from Brooks' book:
1: The Missing Universe (Dark Matter problem)
2: The Pioneer Anomaly (Pioneer spacecraft deflecting from Newtonian trajectory)
3: Varying Constants (physics constants seem to vary over geologic timescales)
4: Cold Fusion (is back and with more data)
5: Life (materialism vs intelligent design)
6: Viking (on Mars in 1976, the labelled release experiment found life)
7: The Wow! signal (radio telescope detected monochromatic beam)
8: A Giant Virus
9: Death (evo/devo debate in evolution)
10: Sex (seems overly complicated, and not at all Darwinian)
11: Free will (materialism doesn't allow it)
12: The Placebo Effect (swallowing sugar pills, injecting saline solution works like a drug)
13: Homeopathy (diluted medicine still works)
In looking over the list, I can see that the earlier blog addressed issues 1,2,7,9,10,11. My treatment of #1 was somewhat cursory, so let me address it at greater length.
1. The Missing Universe
The problem is simple, the Andromeda galaxy (and all other galaxies examined) should be flying apart because the gravity from stars is about 10% of the needed mass to hold everything together. Is there something we can't see (hence, dark) which is providing the gravity to hold the galaxy together?
Well, there has been no shortage of suggestions. The problem is whether any of them make sense. If they were, say, Jupiter sized planets, there would have to be 10-100X more of them than the stars. Many of them would be in orbit about stars, on average some 5-10 per star. We should see both "wobbling" of the star, as well as eclipsing of the star. And while we are up to about 100 extrasolar "Jupiters", it is nowhere near the number needed. The recently launched
Kepler mission is designed to monitor 100,000 stars for this eclipsing behavior, and by all accounts should detect 1000's of such Jupiters at the current concentration, but far below the concentration needed to explain the dark matter problem.
Well, could it be hiding in Earth- or Moon-sized objects? Once again, the sheer quantity needed, some 1000-10,000 for each star, is daunting. But Kepler can certainly find even the small guys if they are there.
How about a gas, could the missing matter be hiding in clouds of cold hydrogen gas, the famous HI regions? Well space is a pretty good vacuum, and the density of even these "dense" clouds would make vacuum-pump manufacturers envious. At 3 or even 10 atoms/cc, we're talking of galactic sized clouds to hold the necessary mass. And even at this low density, starlight passing through parsecs of hydrogen gets absorbed and re-emitted, causing the HI regions to glow, and also stamping the starlight with "absorption band" fingerprints. If the missing matter were gaseous, we would have lots of evidence of it.
What about those dark nebula that only absorb light? That's because they aren't gaseous, but dusty. And once again, there's enough dust there that its presence can be detected by blocking the light behind it. If the dust gets above a micron in size, then it collapses into the stars, if it is below a micron, it gets pushed around by starlight. So not only do we need more dust than is presently observed, but it won't stay put for the 12 billion year lifetime of the galaxy.
The problem is one of cross-sections. If we make the missing matter in small enough pieces to spread it evenly around, then it has such a large optical cross-section we can see it. If we make the missing matter in big chunks, then it has such a large gravitational cross-section we can see it. This has led theorists to propose MACHOs and WIMPs, or massive compact halo objects and weakly interacting massive particles.
MACHOs are usually thought of as neutron stars, black holes, brown dwarfs, and other very faint stars. This is possible, though all of these have huge gravitational cross sections and should be observable by the things that get attracted to them. For example, black holes may not emit radiation, but when they pull gas from a neighboring star, they end up with an accretion disk that is extremely bright in the X-ray sky.
WIMPs are speculative subatomic particles like neutrinos that have some mass, yet don't emit or absorb light and have almost no interaction with matter. The problem is that neutrinos are thought to be about 10-15ev in mass, and there just aren't enough of them produced by stellar activity to account for the missing mass. Furthermore, if 10X the mass of the sun is present in a gravitational halo around the sun of trapped WIMPs, we'd have noticed it by now.
A recent astronomical discovery of
two galaxies passing through each other gave a whole new perspective on the problem. High optical cross section corresponds to high collision cross section, so if the missing matter were dust or smaller, the two galaxies should have had lots of hot matter at a bow shock. Well they had some, but when they mapped the gravity they found most of the mass was ahead of the shock, the dark matter of the two galaxies had interpenetrated without slowing down. So here is the mystery, the dark matter has both a small collision cross section and a small gravitational cross section. How can it be both?
The answer is deceptively simple. It is bigger than dust, smaller than planets, and "hot" enough to survive 12 billion years without coalescing.
Fast-moving, black-crusty comets fit the bill perfectly (though Lou Frank's data don't). But to make all that ice would mean that big bang nucleosynthesis models, which predict the ratios of H/He/Li and very little O, must be off, or early universe star formation was much faster than expected. Both subjects are now getting re-examined (plasma physics was ignored in BBN models, and "cold flows" ignored in early universe cosmologies), and I suspect the hypothesis will be strengthened rather than weakened in coming years. And it would also provide another factor of a billion in the
locations for life.
#2 we dealt with
before.
#3 Varying Constants
Physical constants are ratios that science can't explain, and therefore take as givens, boundary conditions, universal constants.
Brandon Carter is famous for a 1974 neologism that explained how sensitive our universe is to those inexplicable constants, for if they had been any different, we wouldn't be here to observe it. This "fine-tuning argument" has been taken up by Intelligent Design and Creationists as evidence of a Creator, while the counter-arguments have been either
(a) Carter's original "Anthropic Principle", that since we couldn't observe any set of constants that exclude us, it is mere observational bias, and not evidence of "fine tuning"; or (b) there are
gazillions of unobserved universes with different constants, which when combined with (a) allow pure chance to have provided our universe.
Now Eliot Sober is a U. Wisc at Madison philosopher who really would like to support chance as the explanation of humans, but even he has trouble with argument (a). If you are inclined toward that argument, you should take a look at
this paper using Baysean statistics. And
despite the NYT suggesting that a multiverse theory doesn't exclude God, it implicitly requires that each baby universe in the set of multi-verses will have a different set of physical constants, which is no more supported than the idea of baby-universes in the first place. So breath-taking are these assumptions, that it is almost impossible to spoof, but
Rob Bryanton has managed it, which is a funnier version of
my "borg" disproof.
In any case, discovering that physical constants vary over geologic time would wreak havoc with both the "fine tuning" argument, as well as bolster the "multiverse" hypothesis. But mostly it would give cosmologists headaches. And my gut feeling is that it can't be true, that physical constants are tied up in the character of God, "
in whom there is no shadow due to changing".
#4 Cold Fusion
This was one of those
discoveries 15 years ago that everyone wanted to be true, but no one could duplicate. Consequently, the discoverers were branded charlatans, and run out on a rail. But nevertheless, a small core of true believers kept working on it, and 15 years later, there are repeatable results, albeit no theory to explain them. Historically this isn't so unreasonable, the discovery of superconductivity took 40 years to explain, and likewise spectroscopy took
100 years to explain the discrete lines. In our modern hubris, we think mysteries that last more than 4 years are like wars that last longer than 4 years: a complete and utter disaster. (I have also
hypothesized that there are observational QM effects that may cause the results to depend on whether you believe in them.)
So I think Michael Brooks includes this mystery more because of the animosity that it generates than for the delay in theoretical understanding. Perhaps because it has been a devilishly difficult experiment to replicate. But then again, so was Michelson-Morely, so perhaps it is the anger engendered that is the greatest mystery.
5: Life--you might see my somewhat
speculative papers about comets.
6: Viking-- I have blogged on
earlier and even
earlier.
7: The Wow! signal-- I
discussed earlier.
8: A Giant virus
(haven't seen anything from his book on this)
9: Death
I've discussed in my booklet on
Viruses, Genes and Sin, how death solves the parasite load problem. Thus death is a gift of God to counter the curse of sin. Think of it as a Sleeping Beauty fairytale, that the curse of the evil aunt is blunted by the blessing of sleep. That's why death is planned, not accidental. If we are puzzled by this, thinking that eternal life should be the goal of a Darwinian evolutionary model, then we need only read Genesis 1-3 to understand the purpose of death.
10: Sex--
discussed earlier.
11: Free will --
discussed earlier.
12: The Placebo effect
This one is really only a problem for materialists. That is, people who believe that all communication must occur by transfer of particles, and that there are no long range correlations in space and time. I have
earlier written on the correlations of space-time, but here I would only point out that repetitive actions will often achieve "muscle memory", which is somehow faster and less conscious than "brain memory". I watch my wife practising Chopin etudes, and over time her fingers become a blur of notes that she could not possibly be remembering in realtime, with the 250ms latency of the nervous system.
Thus the continued application of a medicine does not itself cure the pain, but rather initiate a series of dominos that result in amelioration of symptoms. If injection of morphine for 5 days triggers the endomorphins of the body to eliminate pain, what is to prevent the bodies "muscle memory" from releasing endomorphins even before the needle penetrates the skin or when replaced with saline? Such adaptive behavior has many beneficial consequences, not least is the playing of Chopin etudes, and it would be well within the bodies capabilities to have multiple triggers for certain responses. The only mystery about placebos is that it has taken this long to understand that the body can learn sub-conscious ways to control homeostasis.
12: Homeopathy
I have little sympathy for this practice, though I do understand its philosophy. If one can cure without dangerous chemicals, I am all for it. But were it reliably true, then Chinese medicine would be a whole lot more successful. For when I am sick, I and my pathogens lack the patience to try a hundred lesser treatments, and therefore I find it marginally to deadly dangerous as a proposed cure.
No doubt there are new things being discovered about water every year, and perhaps many of the homeopathic effects will find their explanation in future physics. Indeed, I consider myself the first to have discovered the
work function of water exposed to UV light. But life is too precious to experiment on people with novel theories of water. Why have not homeopaths proved their case on a mouse model, like all the other drug companies? With regard to human treatments, the question is not qualitative (does a treatment work) but qualitative (how reliably does it work). Until homeopathy answers that question, it is not a treatment I would willingly undergo.
The
New Scientist abstract now lists the 13 top items differently. Here's their new list:
NS 1. The placebo effect (same as #12)
NS 2. The horizon problem (new)
NS 3. Ultra-energetic Cosmic Rays (new)
NS 4. Belfast Homeopathy results (same as #13)
NS 5. Dark Matter (same as #1)
NS 6. Viking's Methane (same as #6)
NS 7. Tetraneutrons (new)
NS 8. The Pioneer Anomaly (same as #2)
NS 9. Dark Energy (new)
NS 10. The Kuiper Cliff (new)
NS 11. The Wow signal (same as #7)
NS 12. Not-so-constant constants (same as #3)
NS 13. Cold Fusion (same as #4)
NS 0. Not one to shirk my duty, here are my thoughts on the new list, as well as vague surprise that Michael has removed all his biology mysteries. I suppose the Darwinistas were upset that he would call an established fact "a mystery". Once again, it is the scientists who are the biggest mystery.
NS 2. The horizon problem is one of cosmological statistical-mechanics. If parts of the Big Bang have been incommunicado for 12 billion years, how did they all end up within millikelvins of each other, as if they were in some sort of equilibrium exchanging energy?
Well there are several ways to solve this problem. The "inflation" scenario has exchange through a "faster-than-light" expansion that solves the problem, but introduces another. It is one specific example of a tertium quid. That is, if A-->C, and C-->A, but A and C have never met each other, we have correlation without causation. This can be accounted for if there is a third object B, such that B-->A and B-->C. For example, lipstick and breast cancer are highly correlated, but not causal, because they are both things causally antecedent to both, namely, women. Therefore if it looks like the universe is in thermal equilibrium, though parts haven't spoken to each other in 12 billion years, perhaps it is because they are both causally connected to a third thing. It could be the physics below the Planck time, it could be a new force field (responsible for inflation), or even God. Given the freedom to pick any correlation one desires, such as inflation, the real mystery is why we think cosmology is such an exact science.
NS 3. Ultra-energetic Cosmic rays.
I've actually given
talks on this before, where I propose a galactic (Milky Way) source for the cosmic rays below the "ankle". Michael is concerned about sources above the "ankle", which data suggest must have a source within our galaxy. I
have proposed a more hypothetical "DC" accelerator for these particles, produced in cosmic jets. Since our Milky Way is thought to have a massive black hole at the center, it seems reasonable to assume a jet associated with our own galaxy that can make these TeV cosmic rays.
NS 6. Viking's Methane. This is just a
rehash of
Gil Levin's experiment, but apparently the ESA mission has remotely detected methane on Mars, now confirmed with Earth-based HST measurements. The reason Viking didn't directly detect methane with its atmospheric mass spectrometer, is that mass channel 16 was intentionally "blocked" in the design. Why? They didn't think there would be any methane to see.
NS 7. Tetraneutrons
Not being a particle physicist, this one takes me by surprise. Given the ability of Los Alamos bomb codes to calculate nuclear reactions to the sub-percent level, I would have thought that all subatomic particles and forces were accounted for to great detail, barring some high energy stuff like the TeV Higgs Boson. But neutrons at 940MeV are so mundane, one would have thought that any binding force (or virtual particle E < 940MeV) would have been well researched by now. Then again, when the helioseismologists tested stellar interior models also derived from bomb codes, the mistakes were at the 10% level rather than the advertised sub-percent. So perhaps nuclear physics isn't so cut-and-dried as I had been led to believe.
NS 9. Dark Energy
I've blogged on this
earlier, as well as in the earlier Brook's
review.
NS 10. The Kuiper Cliff
This one hasn't been a mystery very long, simply because we haven't long possessed the ability to look for planetismals outside the orbit of Neptune where the light is so dim. So chalk one up for new technology: high quantum efficient CCD's and robotic telescopes.
Since we haven't been looking for very long, this mystery might be solved tomorrow, and I would hesitate to include it with more venerable mysteries. Nevertheless, there is a peculiar correlation with my work. Seems that several of the Kuiper objects are comets, or as some would like to say, water-bearing asteroids. I looked at the distribution of comets in a
earlier paper, and concluded that there was enhanced radial diffusion occurring from the Kuiper belt. I attributed this to the effect of "steam jets" whenever a comet came within the orbit of Mars. This would change the apogee distance of the comet, appearing as enhanced diffusion. Now most of the objects that Michael is talking about are on circular, not elliptical orbits, though given their short observation times, there may be some difficulty telling the two types of orbits apart. It would be my hypothesis that the absence of orbits on the outer edge of the Kuiper belt, is in part due to enhanced radial diffusion of comets that spend large portions of their time in this region.
If Michael reads this blog, I hope it sets his mind at rest; for the science is far less surprising than the scientists.