Category Archives: Science and Modern Society

A Couple of Questions for Readers

Today I’m looking for insights from readers on two issues that were nagging me over the weekend.

The first issue has to do with the Fukushima nuclear accident and subsequent radiation fears, which I first brought up on this blog last week.   I’ve been thinking about how to write articles that explain radioactivity and radiation in rather plain language, and about what we know is dangerous and what we know is not.  One of the challenges is to confront the extreme irrationality of people’s fear of radioactivity.  I’d like to hear my readers’ opinions of where this fear really comes from.  One explanation of this fear that you’ll commonly read is that “radioactivity is scary because you can’t see or smell or feel it”.  But that makes no sense; you can’t see, smell, or feel viruses either, or low levels of chemicals, so why aren’t people equally afraid of those things?  Especially since the average person is far more at risk of getting cancer or other potentially deadly diseases from viruses (such as papilloma) or from chemicals (asbestos, benzene, etc.) then from radioactivity, despite all the atmospheric nuclear tests in the 1950s and 1960s and the Chernobyl and Fukushima nuclear plant accidents.  So I don’t think this explanation is correct; there are plenty of invisible scary things in the world, and people’s fears are totally out of proportion to the true risks.  I have my own suspicions as to the real causes, but I am wondering what my readers think.

The second issue is more technical. Comet ISON, dubbed, as is typical of our sensationalist age, “comet of the century” before it has even become easily visible [and it might still be a dud, or it might be the best of the year or even the last twenty years; but of the century? check back in 2099!]) is approaching the sun.  There is indeed the tentative possibility, if it survives its very close encounter with the sun on November 28th, that it will give us a spectacular early morning display in December.  In preparation, I’m wanting to read more details about the properties of cometary tails, which are generated by the physics of particles and fields (photons, ions, magnetic fields, momentum conservation, etc.).  [Here's a nice video of ISON's tail and its interaction with the solar wind, the stream of charged particles emanating from the sun; also visible to its upper right is Comet Encke, which by chance is also near the sun.  By the way you can also see, watching Encke, that its tail is not a trail; it does not point along its direction of motion but instead points away from the sun.] But I’ve been unable to find anything online other than vague descriptions with no technical information, or references to books or review articles from several decades ago.  Do any of my readers know of a roughly up-to-date technical introduction to the physics of comets’ tails?

Thanks!

Evolution [in]-Action

For general readership

Evolution really happens in nature: we know this from the frightening rate at which bacterial species, faced with our most powerful antibiotics, manage to find ways around them.

More precisely, a certain amount of natural variability and accidental mutations within bacterial populations, and the huge rate at which bacteria reproduce themselves (a single bacterium at dawn may be billions by sunset), essentially assures that eventually, simply by accident, and relatively soon, a bacterium will be “born” that is immune to any particular antibiotic. And then this bacterium, the sole survivor of the onslaught to which its siblings have succumbed, and reproducing by dividing into “children” that also can survive, soon gives rise to a subspecies of its own, against which this antibiotic is useless.  By using the antibiotic again and again, killing off the bacteria from other subspecies, we eventually assure that this unbeatable subspecies becomes more and more common compared to its cousins.

In recent years, bacteria have appeared for which no antibiotic treatment exists.  The rate of the evolution of these bacteria has outpaced the rate at which biologists and medical researchers can find and develop new antibiotic treatments.  The Center for Disease Control is extremely worried about this, and its director Tom Frieden just published a blog post that everyone should read.  Here’s one quotation:

To help draw attention to CRE and other top antibiotic-resistance threats, the Center for Disease Control recently published its first report on the current antibiotic resistance threat to the U.S. The report estimates that each year in the United States, at least 2 million people become infected with bacteria resistant to antibiotics, and at least 23,000 people die as a result.

Note this extraordinary statement: every year, 1 in 150 people in the United States will be infected with bacteria that are resistant to a classic antibiotic every year, and 1% of them will die, some fraction of them because of this resistance.  Let’s put that in perspective: assuming there were no increase in the number of bacteria or improvements in treatment over the next 50 years, your chance of being infected by such a bacterium during that time is roughly 25%.  In short, this will very likely happen to someone you know in the next few years, and someone in your family in coming decades.  (It’s already happened to someone in my extended family.)  And of course, since they are hard to fight, these bacteria are likely to spread, so the rate of infection will become worse if nothing is done.

Here’s another quotation: 

Every doctor must commit to use antibiotics only when needed, and to use antibiotics for only as long as they are needed. Patients need to understand that “more” drugs does not equal “better” drugs. The right treatment is the best treatment – and that isn’t antibiotics for every infection or every illness.

Now why is he making this point so strongly? Let me end by quoting from the preamble to the report he mentions:

The use of antibiotics is the single most important factor leading to antibiotic resistance around the world. Antibiotics are among the most commonly prescribed drugs used in human medicine. However, up to 50% of all the antibiotics prescribed for people are not needed or are not optimally effective as prescribed. Antibiotics are also commonly used in food animals to prevent, control, and treat disease, and to promote the growth of food-producing animals. The use of antibiotics for promoting growth is not necessary,
and the practice should be phased out.

I hope everyone pays close attention to Frieden’s post and its message, and spreads the word among the people that they know.  Doing so may someday help save the life of someone you care about, or even your own.

The Mess at Fukushima, and The Need for a Scientific Lens

Ever since the horrific earthquake, tsunami and ensuing nuclear accidents hit north-eastern Japan in March of 2011, the world has been keeping an eye on Fukushima, where the Fukushima Daiichi nuclear power plant suffered extraordinary amounts of damage.  Initially the news out of the power plant, operated by the company TEPCO, was awful, but gradually the situation seemed to be increasingly under some control.  But that control has not been convincingly secured, and has even perhaps been slipping of late.  And the worries about a variety of possible risks from the plant have been growing, especially because the clean-up at the plant is still run by TEPCO, which has engaged in repeated cover-ups and poor decisions… not to mention the fact that it’s a power company, not a nuclear accident site cleanup company.  I find it extraordinary that the situation hasn’t been put into the hands of a blue-ribbon international panel of nuclear scientists and engineers, with full power to make decisions and with full transparency for all to see as to what is going on.  It’s taken the Japanese government far too long to step in.

I’m bringing this topic up now because TEPCO is finally ready to address one of the major issues that they face in the clean-up.  In addition to finding ways to deal with the melted-down nuclear fuel at Reactors 1, 2 and 3, which will take years, they have to deal with the stored and mostly undamaged fuel rods that are sitting outside of Reactor 4, in a water-filled pool.  The water keeps the fuel cool, and right now there’s nothing wrong with the pool or the cooling.  The problem is that this pool is on the 3rd floor of the Reactor 4 building, which was damaged in a (chemical, not nuclear) hydrogen explosion shortly after the earthquake… and it would be better to get the fuel rods into a safer pool, at ground level, outside of the compromised building.  This is not easy for many reasons, and apparently there is some risk involved — not risk of a nuclear explosion, which is physically impossible in these circumstances, but of some amount of radioactive gas being produced and released into the atmosphere if the fuel rods are not kept submerged in water or are otherwise damaged.  However, I’m not precisely clear on the nature of this risk.

Just the same as anyone else who might be affected if fish from the Pacific become unsafe to eat (which, as far as I can tell so far, remains the main risk to areas outside Japan), I want to know what is happening at Fukushima and what exactly the risks are.  But I’m not an expert on this subject.  Just because I’m a scientist doesn’t mean that it’s that much easier for me to figure out what’s really going on. It’s just perhaps easier for me, compared to the general reader, to recognize misinformation for what it is.  And when I look around the web, I am seeing huge amounts of it.  (For instance, starfish on U.S. coastlines are being afflicted by some sort of disease; around the web you will see suggestions that this has something to do with Fukushima, which, given that the amount of Fukushima-related radioactivity currently in the Pacific is small, is manifestly ridiculous.)

There are good reasons to be concerned that things are at risk of getting out of hand on many different fronts, both in terms of actions on the ground and in terms of public understanding.  On the one hand, I’m reading more and more scare-mongering: irresponsible statements made by non-experts, such as the ones about starfish, that are starting to frighten my friends and neighbors unnecessarily, especially on the west coast of the United States.  (Here’s a response by a deep-sea biologist to one of the most egregious; I can’t directly verify all of the points he makes, but many of them were obvious to me even before I found his website.)  On the other hand, I’m not at all convinced, given their terrible track record, that TEPCO is capable of dealing with the extreme technical difficulty and considerable danger of putting their nuclear plant back into a safe condition without there being additional significant releases of radioactive material.  And meanwhile, media reporting is just not sufficiently reliable; the journalists aren’t experts and often don’t understand the issues well enough to get it all straight or put it in proper context.

If there were ever a time when level-headed scientific discussion, careful calculation and thoughtful consideration were needed in a public setting, this would be it.

I haven’t yet found a sensible, trust-inspiring blog that does for nuclear engineering and radiation safety what I try to do for particle physics (though this one looks somewhat promising.)  Consequently, I don’t really have a way to understand the whole story and to gauge it properly.  So I’d like to find a way to use my website and its readers, some of whom surely know more about nuclear engineering and radioactivity risks than I do, and some of whom are perhaps getting more information than I am, to assemble a clearer understanding of what the risks and dangers really are and are not.

Fair warning: In contrast to my usual policy, I am going to be strictly editing the comments on this post, and all similar posts on Fukushima.  I will accept thoughtful scientifically-based discussion, and links to such discussion, only. I want neither my own mind nor my readers’ cluttered with unscientific chatter from non-experts.  Polemical diatribes will be deleted; activism for or against nuclear power is inappropriate here [I happen to oppose nuclear power in its current form, but that's beside the point right now]; and unscientific assertions without any support from replicated studies will be marked as such, and if sufficiently egregious, deleted.  My goal is the same as that of most people: to get a better grasp of the situation, and to get a clearer sense of what to worry about and what not to worry about, both for now and looking into the future.

So: do I have any readers with expertise in this area? If you’re one of them, can you help us establish a baseline of solid science that we can build on?  Does anyone know of particularly even-handed and sensible blogs by experts that we can draw on?  Websites with data or resources that are run by people without an obvious big axe to grind?  One of the big problems I find is that there are plenty of scientific studies quoted on blogs, but few guides to the non-expert reader to help us put the results in precise perspective.

By the way, here’s one site that shows the radioactivity levels in and around Berkeley, California; as far as I can see, nothing above normal levels has been measured for well over a year, and never were levels high even in 2011.  http://www.nuc.berkeley.edu/UCBAirSampling

Questions and Answers About Dark Matter post-LUX

Since the mainstream news media, in their reporting on the new result from the LUX experiment I wrote about Wednesday, insists on confusing the public with their articles and headlines, I thought I’d better write a short post reminding my readers what we do and don’t know about dark matter.

  • Do we know dark matter exists?

Scientists are, collectively, pretty darn sure, though not 100% certain. Certainly something is out there that acts a lot like a dark form of matter (i.e. something that gravitates and clumps, but doesn’t shine, either in visible light or in any other form of electromagnetic waves). There have been some proposals that try to get around dark matter, by modifying gravity, but these haven’t worked that well. Meanwhile the evidence that there really is dark stuff out there that really behaves like matter continues to grow year by year, and every claim that it actually isn’t there (such as this one I wrote about — see the second half of the article) has turned out to be wrong.  Dark matter is needed to explain features of the cosmic microwave background, to explain how galaxies form, to explain why we see certain types of gravitational lensing, etc. etc.  No one alternative can explain all of these things.  And dark matter easily arises in many particle physics theories, so it’s not hard to imagine it might be created in the early universe and be a dominant player today.

  • Do we know dark matter is made from particles (i.e. ultra-microscopic objects with uniform properties)?

No, that’s not certain. Particles would do the job, but that’s not a proof it is made from particles.

  • If dark matter is made from particles, do we know these are Weakly Interacting Massive Particles (WIMPs) — to be precise, particles that interact with the Standard Model via the weak nuclear force or the Higgs force or something else we already know about?

No. Dark matter could be WIMPs. Or dark matter could be made from a very different type of particle called “axions”. Or dark matter could be made from particles that aren’t of either of these types.  This could include particles that only interact with ordinary matter through the force of gravity, which could make them very, very hard to detect.

  • Do most scientists believe dark matter is made from WIMPs? (This was claimed to be true in several news articles.)

As far as I can tell, most experts do not know what to think; some have a bias toward one idea or another, but when pressed admit there’s no way to know. Many scientists think WIMPs are a good candidate, but I’ve never heard anyone say they are the only one.

Partly because they can. Sometimes science involves looking under the lamppost for your keys. You look where you can because you can look there, and you may get lucky — it has happened many times before in history.   That’s fine as long as you remember that’s what you are doing.

Not that WIMPs are the only things that people are looking for. They can also look for axions, and there are experiments doing that search too. Looking for other types of dark matter particles directly is sometimes very difficult. Some of these other types of particles could be found by the experiments at the Large Hadron Collider [LHC] (and people are looking.) Others could be found by experiments such as FERMI and AMS, through the effect of dark matter annihilation to known particles (and people are looking; there’s even a hint, not yet shown to be wrong). Still other possible types of dark matter particles are completely inaccessible to modern experiments, and may remain so for a long time to come.

  • If we don’t know dark matter is particles, or that those particles are WIMPs, then why do the headlines say “dark matter search in final phase” in reference to the new result from LUX, even though LUX is mainly only looking for WIMPs?

Don’t ask me. Ask the editors at CBS and the BBC why their headlines about science are so often inaccurate.

The search for dark matter will end when some type of dark matter is found (or somehow shown convincingly not to exist), not before. The former could happen any day; the latter will not happen anytime soon.  The only thing that is currently approaching its end is the search for WIMPs as the dark matter (and even that search will not, unfortunately, end as soon or as conclusively as we would like.) If WIMPs aren’t found, that just probably means that dark matter is something else on the list I gave you above: some other type of particle, or some other type of thing that isn’t a particle. Or it could mean that dark matter forms clumps, rather than being smoothly distributed through our galaxy, and that we’re unlucky enough to be in an empty zone.  Certainly, if LUX and XENON1T and the other current experiments don’t find anything, we will not be able conclude that dark matter doesn’t exist. Only those who don’t understand the science will attempt to draw that conclusion.

  • So why is the LUX experiment’s result so important?

Well, it’s important, but not amazingly important, because indeed, (a) they didn’t find anything, and (b) it’s not like they ruled out a whole class of possibilities (e.g. WIMPs) all at once. But still, (i) they did rule out a possibility that several other experiments were hinting at, and that’s important, because it settles an outstanding scientific issue,  and (ii) their experiment works very, very well, which is also important, because it means they have a better chance at a discovery in their next round of measurements than they would have otherwise. In short: they deserve and will get a lot of praise and admiration for their work… but their result, unlike the discover of the Higgs particle by the LHC experiments, isn’t Nobel Prize-worthy. And indeed, it’s not getting a front-page spread in the New York Times, for good reason.

An Interesting Data Point on Climate

Particles are just so cool, and so very useful.  Scientists can learn about the past — for example, past climate — using “carbon dating”, a combination of biology and nuclear physics.

In this article in Geophysics Letters, covered in this Colorado University press release (with a somewhat inaccurate title), the abstract contains the statements…

…the extent to which recent Arctic warming has been anomalous with respect to long-term natural climate variability remains uncertain. Here we use 145 radiocarbon dates on rooted tundra plants revealed by receding cold-based ice caps in the Eastern Canadian Arctic to show that 5000 years of regional summertime cooling has been reversed, with average summer temperatures of the last ~100 years now higher than during any century in more than 44,000 years,…

Now how does this work? Continue reading

More Scientist-Hostages Uncovered

Just in case you weren’t convinced by yesterday’s post that the shutdown, following on a sequester and a recession, is doing some real damage to this nation’s scientists, science, and future, here is another link for you.

Jonathan Lilly is a oceanographer, a senior research scientist at NorthWest Research Associates in Redmond, Washington, and I can vouch that he is a first-rate scientist and an excellent blogger.  He writes in an article entitled

Stories from the front: oceanographers navigate the government shutdown

about a wide range of damaging problems affecting this field of study.  What’s nice about this post, compared to my own general one from yesterday, is that he has a lot of specific detail.

Here are some other links, demonstrating the breadth and depth of the impact:

http://www.npr.org/blogs/health/2013/10/10/230750627/shutdown-imperils-costly-lab-mice-years-of-research

http://www.wired.com/wiredscience/2013/10/what-does-a-federal-shutdown-mean-for-conservation-and-ag-science/

http://www.forbes.com/sites/eliseackerman/2013/10/07/the-shutdown-versus-science-national-observatory-latest-victim-of-washington-politics/

http://www.wired.com/wiredscience/2013/10/government-shutdown-affects-biomedical-research/

Help! I’m a Hostage! (D – 7)

Maybe you think this shutdown isn’t all that bad?  Perhaps you’re not talking to scientists, or thinking about their role in society. The effects of the government shutdown continue to ripple outward.  Scientific research doesn’t cope well with shutdowns.

http://www.ibtimes.com/us-government-shutdown-antarctic-research-program-5-other-shuttered-science-programs-1419918

In many fields, the research has to be maintained continuously; if you shut it down, even for a short period, all your work is wasted.   Continue reading

Freeman Dyson, 90, Still Disturbing the Universe

I spent the last two days at an extraordinary conference, “Dreams of Earth and Sky”, celebrating the life and career of an extraordinary man, one of the many fascinating scientists whom I have had the good fortune to meet. I am referring to Freeman Dyson, professor at the Institute for Advanced Study (IAS), whose career has spanned so many subfields of science and beyond that the two-day conference simply wasn’t able to represent them all.

DysonPhoto

The event, held on the campus of the IAS, marked Dyson’s 90th year on the planet and his 60th year as a professor. (In fact his first stay at the IAS was a few years even earlier than that.) The IAS was then still a young institution; Albert Einstein, John Von Neumann, Kurt Gödel and J. Robert Oppenheimer were among the faculty. Dyson’s most famous work in my own field was on the foundations of the quantum field theory of the electromagnetic force, “quantum electrodynamics”, or “QED”.  His work helped explain its mathematical underpinnings and clarify how it worked, and so impressed Oppenheimer that he got Dyson a faculty position at the IAS. This work was done at a very young age.  By the time I arrived to work at the IAS in 1996, Dyson had officially retired, but was often in his office and involved in lunchtime conversations, mostly with the astronomers and astrophysicists, which is where a lot of his late career work has been centered.

Retirement certainly hasn’t stopped Dyson’s activity. His mind seems to be ageless; he is spry, attentive, sharp, and still doing science and writing about it and other topics. When I went up to congratulate him, I was surprised that he not only remembered who I was, he remembered what I had been working on in 1992, when, as an unknown graduate student on the other coast, I had sent him a paper I had written.

By the way, it’s somewhat bizarre that Dyson never won a Nobel Prize.  Arguably it is part of the nature of the awarding process, which typically rewards a specific, deep line of research, and not a polymath whose contributions are spread widely.  Just goes to show that you have to look at the content of a person’s life and work, not the prizes that someone thought fit to award to him or her.  Still, he has his share: Dannie Heineman Prize for Mathematical Physics 1965; German Physical Society, Max Planck Medal 1969; Harvey Prize 1977; Wolf Foundation Prize in Physics 1981; American Association of Physics Teachers, Oersted Medal 1991; Enrico Fermi Award 1995; Templeton Prize for Progress in Religion 2000; Henri Poincaré Prize 2012.

The thirteen talks and several brief comments given at the conference, all of which in one way or another related to Dyson’s work, were organized into sessions on mathematics, on physics and chemistry, on astronomy and astrobiology, and on public affairs. All of the speakers were eminent in their fields, and I encourage you to explore their websites and writings, some of which were controversial, all of which were interesting. For non-scientists, I especially recommend Stanford Professor Emeritus Sid Drell’s extremely interesting talk about nuclear disarmament (which he’s been working towards for decades), and a thought-provoking if disconcertingly slick presentation by Dr. Amory Lovins of the Rocky Mountain Institute on what he sees as a completely realistic effort, already underway, to wean the United States of its addiction to oil — with no net cost. Those with a small to moderate amount of scientific background may especially enjoy MIT Professor Sara Seager’s work on efforts to discover and study planets beyond our own solar system, Texas Professor Bill Press’s proposal for how to rethink the process of drug trials and approvals in the age of electronic patient records, Sir Martin Rees’s views on the state of our understanding of the universe, and Caltech’s Joseph Kirschvink’s contention that scientific evidence tends to favor the notion that life on this planet most likely started on Mars.

But really, if you haven’t heard about all the different things Freeman Dyson has done, or read any of his writings, you should not miss the opportunity. Start here and here, and enjoy!

Many happy returns, Professor Dyson; you have been an inspiration and a role model for several generations of young scientists, and may you have many more happy and healthy years to come!