Quick Thoughts on Diversity in Physics

Earlier this month, during oral arguments for Fisher v. University of Texas, Chief Justice John Roberts asked what perspective an African-American student would offer in physics classrooms. The group Equity and Inclusion in Physics and Astronomy has written an open letter about why this line of questioning may miss the point about diversity in the classroom. But it also seems worth pointing out why culture does matter in physics (and science more broadly).

So nature is nature and people can develop theoretical understanding of it anywhere and it should be similar (I think. This is actually glossing over what I imagine is a deep philosophy of science question.) But nature is also incredibly vast. People approach studies of nature in ways that can reflect their culture. Someone may choose to study a phenomenon because it is one they see often in their lives. Or they may develop an analogy between theory and some aspect of culture that helps them better understand a concept. You can’t wax philosphical about Kekule thinking of ouroboros when he was studying the structure of benzene without admitting that culture has some influence on how people approach science. There are literally entire books and articles about Einstein and Poincare being influenced by sociotechnical issues of late 19th/early 20th century Europe as they developed concepts that would lead to Einstein’s theories of relativity. A physics community that is a monoculture then misses out on other influences and perspectives. So yes, physics should be diverse, and more importantly, physics should be welcoming to all kinds of people.

It’s also worth pointing out this becomes immensely important in engineering and technology, where the problems people choose to study are often immensely influenced by their life experiences. For instance, I have heard people say that India does a great deal of research on speech recognition as a user interface because India still has a large population that cannot read or write, and even then, they may not all use the same language.

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Going over the Critique of Cosmos part 1 and a brief review of part 2

Like I said before, Hank Campbell’s had some interesting critiques of the first episode of Cosmos. I thought nearly all of them missed the mark, and to be honest, it seems like he’s being a bit of a science hipster here. I want to go more in depth, and I’ll do that here. Let’s go through his points

1. Venus was not caused by global warming

Let’s look at what Campbell says:  “We have to ask why he thinks Venus is the way it is due to the greenhouse effect — which is another way of saying global warming. Venus is almost 900 degrees Fahrenheit and the clouds are sulfuric acid. Even the most aggressive climate change models and their 20-foot ocean rises don’t predict that for Earth… If this sequel to Cosmos had been made in 1989 the screenwriters of Cosmos would have invoked acid rain on Venus instead of global warming. Regardless, CO2 did not cause the poisonous conditions on Venus; instead, CO2 is an effect of the poisonous conditions on Venus. Invoking the greenhouse effect when talking about Venus is like blaming ocean liners for inventing barnacles.

Okay, but global warming isn’t the same as the greenhouse effect.  If it weren’t for the CO2, SO2, and H2O, Earth’s surface temperature would be significantly lower. That is the definition of the greenhouse effect. More technically, the greenhouse effect is when a gas in an atmosphere can absorb heat radiated from a planet surface, which then redirects some of the heat escaping from the planet back towards the surface. This shift the temperature equilibrium to higher than it would without the greenhosue gas. In an exchange on a follow-up on his website, Science 2.0, Campbell says the real culprit is hydrogen escape. (Note: I’m the “Matt” participating in the comment section.) “On Venus gravity, hydrogen is already light so a lack of gravity causes the water problem to go nuts. No water, CO2 goes crazy – but CO2 did not cause the atmosphere of Venus, Tyson knows it, anyone who knows high school atmospheric science knows it…”

Campbell probably overestimates hydrogen escape by itself. Hydrogen escapes from Earth too (we’re predicted to lose our all water due to hydrogen escape within the next billion years). Also, Venus’ surface gravity is about 90% that of Earth’s, so hydrogen shouldn’t experience that much weaker of a pull to the planet that it does here.  The chain of cause and effect leading to atmospheric changes on Venus doesn’t mean the greenhouse effect doesn’t describe the current temperature, or ever played an effect in the evolution of Venus’ climate. Even planetary scientists describe Venus’ history as the result of a “runaway greenhouse effect”. Once most of Venus’ water was in the atmosphere, it stayed that way because water vapor is also a greenhouse gas and raised the temperature enough to prevent condensation into massive oceans that could have held on to the water longer. (It’s easier to strip hydrogen from molecules in the atmosphere.) This is also why I don’t buy the idea that this segment relates at all to climate change debates. CO2 is not the only greenhouse gas, and this is typically mentioned in modern discussions about methane, and Tyson didn’t actually mention the concentration of CO2 in Venus’ atmosphere. Campbell takes his concern of framing too far here.

2. The Multiverse is Not Science

Campbell: “Any time a scientist begins a sentence with “Many of us suspect,” it is codespeak for “we sit around and discuss it at the bar.”

Why not just let that go as artistic license? When Carl Sagan was filming the originalCosmos program, physicists Alan Guth and Andrei Linde had not even come up with “inflation” for the Big Bang that Tyson mentions casually. Thus, it would not have made it into the original Cosmos as fact. Too much speculation makes the audience wonder if scientists are going to be trusted guides or another version of Dr. Oz and his Miracle Vegetable of the week. Science doesn’t need to toss in speculation to be interesting, because what we know and therefore don’t know is fascinating enough.”

“The multiverse is not science. It is more like an anthropic secular alternative to a divine origin. It’s not science because it can’t be proved or disproved — it’s just postmodernism with some math. And it’s invoked shortly after the introduction where Tyson tells us to test everything.”

I also kind of cringed when Tyson mentioned a multiverse and it even had a visualization with the spaceship of the imagination. But if you pay attention to the language of the episode, you’ll see that the writers were actually being pretty deliberate. Tyson used “suspect” here. But for the rest of the episode, Tyson never describes a scientific theory as anything less than a fact (which is how scientists treat theories). This means Cosmos is not elevating the idea of a multiverse to the level of accepted scientific theory. And it is true that many physicists and cosmologists “suspect” a multiverse.  Also, Campbell seems to only be thinking of a string theory multiverse in his critique. Tyson’s description didn’t specify the “kind” of multiverse, but the description and visualization seemed to suggest one resulting from “chaotic inflation”. That kind of multiverse actually may be testable if we see an “imprint”, and the new gravitational wave measurements suggest chaotic inflation is the inflation model that more closely matches our universe.

3. There is No Sound In Space

Like I said before, there actually isn’t a good defense of this. Tyson wouldn’t accept it in any other show, and I’m surprised he let that happen here.

4. Giordano Bruno Was Not More Important To Science Than Kepler And Galileo

Like I said before “The episode did not claim Bruno was more important than contemporary natural philosophers and empiricists and definitely pointed out that he wasn’t a scientist. Bruno’s ideas, though, do fit in well with the idea of understanding our place in the universe, which was the entire point of the first episode, as stated in like the first five minutes.”

5. The Universe Was Also Not Created in One Year

“On January 1st, we had the Big Bang and on December 31st, I am alive, less than a tiny fraction of a millisecond before midnight. That can’t be right — it took me a whole day just to write this article.

Oh, Cosmos is not being literal? Oddly, a number of religious critics, Tyson included, insist that too many religious people believe the Book of Genesis is taken literally by people who read the Bible. Unless we accept that figurative comparisons help make large ideas manageable, a year is no more accurate than six days — it is instead a completely arbitrary metric invented to show some context for how things evolved.”

Oh my God, seriously? Hank Campbell is trying so hard to not want to be in a culture war that he wound up back in it. First, Tyson is not nearly as involved in the science aspect of the “culture war” as, say, Richard Dawkins. Also, many Americans don’t take the Biblical account of Genesis figuratively. According to a 2012 Gallup poll, 46% of Americans think God created humans instantly in their present form within the last 10,000 years.

All these complaints just seem… odd. Like I said, “science hipster” is the best description I can think of. I was surprised to hear Campbell really liked the second episode. I actually liked that episode less. The description of the evolution of the eye seemed like a just-so story  in some steps, and probably would not win over the creationists who argue that “the eye is too complex to have evolved”. I thought the step showing the evolution of the lens seemed HUGE and it wasn’t associated with an organism like most of the other steps were. I feel like it would have been more straightforward to show the variety of eyes in the context of the tree of life, but maybe I say this because I’m not as familiar with evolutionary biology. The visualization of DNA seemed “too busy” at times, and they kept changing schematic representations without explaining it. I get that DNA doesn’t really look as pretty as it does in my old bio textbooks, but I was unsure of what was being represented at times. I thought the comparison of DNA sequences seemed a bit odd without a description of what base pairs are.

The Titan bit also seemed odd. I liked the description of Titan, but didn’t like the idea of the ship of the imagination visiting a hydrothermal vent (or its analogue) there. To me it seemed like the show was saying the hydrocarbon lakes on Titan are as deep as Earth’s oceans, and unless I’m really behind the times, I don’t think we know the depth that much. And we definitely don’t know if there are hydrothermal vents on Titan, and that visualization wasn’t accompanied by Tyson saying we “suspect” or some other phrase that would give it less of a weight than a theory/fact like the multiverse visualization was.

“Cosmos” is allowed to have a narrative

Neil deGrasse Tyson’s sequel/reboot to Carl Sagan’s Cosmos: A Personal Voyage, Cosmos: A Spacetime Odyssey, premiered last week on Fox and there’s a multitude of reactions to it. One of the most common negative reactions focuses on the episode’s relatively long segment on Giordano Bruno. If you really want to learn more about Bruno and the various other figures people relate him to and see one of the clearest criticisms and replies to defenses of the show, I suggest you look at the Renaissance Mathematicus’ post on the issue. (And if you want to learn REAL history of science, I highly suggest you check out the rest of his blog.)

A very religious friend posted concerns from Catholic commentators that Cosmos is attacking religion here. I argue that both just seem to be taking offense and ignore Tyson’s actual narration during and around this segment. At no point does Tyson criticize faith. If anything, it’s a critique of institutions which both blog posts seem to also acknowledge by saying that structures and actors in the Church may be bad, but that doesn’t mean Catholicism itself is bad. I’d argue the bigger takeaway is that Bruno thought others’ God was too small.

Several people have asked why mention Bruno at all in the show. Because the entire point of this first episode was to establish the scale of the Universe and our place in it. Bruno was one of the first Western thinkers to propose a Universe where humanity and Earth and the Sun are all small and not particularly unique with respect to the rest of the cosmos. though he was still off on how that actually worked out, as detailed in the Renaissance Mathematicus link above. To Bruno, that had immense philosophical implications and he was willing to die for them (and the host of other heterodox beliefs he held). Why should we just ignore that? Tyson (and Sagan!) are both big on the idea that science can inform metaphysics, and Western culture seems to have a fear that science will leave life without meaning. It seems perfectly reasonable for the show to mention a person whose cosmology inspired a lot of his own religious and spiritual thought. 

Hank Campbell, founder of Science 2.0 and one of the co-authors of Science Left Behind, has different criticisms than most about the first episode, saying “Science is cool. Should we care if it’s accurate?” I want to quickly respond to these points, and I’ll go in more depth later. 

  1. The greenhouse effect is in fact different from the idea of global warming, but the greenhouse effect does play a part in the latter.
  2. I kind of cringed too at the reference to a multiverse but considering the language the episode used, I’d say the phrase “many of us suspect [a multiverse]” was chosen precisely because it isn’t an accepted theory.
  3. The first time I watched the episode, I didn’t notice the external sounds in space separate from the soundtrack. It struck me as kind of funny because Tyson would typically destroy any show that did it. He should be held accountable on his own.
  4. The episode did not claim Bruno was more important than contemporary natural philosophers and empiricists and definitely pointed out that he wasn’t a scientist. Bruno’s ideas, though, do fit in well with the idea of understanding our place in the universe, which was the entire point of the first episode, as stated in like the first five minutes.
  5. The age of the universe as 13.8 billion years old was given multiple times, and the introduction to every major historical landmark on the calendar involved Tyson giving both its date on the calendar and a conversion to how many millions or billions of years ago it actually was.

There Might be Life in Space, but This Paper Didn’t Prove It

An article published in the Journal of Cosmology last month made headlines with its bold claim: alien life can be found in Earth’s atmosphere. The rest of the scientific community ins’t convinced. The Journal of Cosmology isn’t a “peer reviewed” journal, which is the gold standard for scientific work. This means papers the journal publishes aren’t really evaluated for quality or accuracy. In fact, it’s even been labelled “predatory” by one research librarian. As a general rule, it’s also really not a good sign when a paper making a bold claim mainly cites other papers by its authors.

The lack of peer review on the paper seems justified; there’s not much data.  The paper relies almost entirely on just microscope images . Virtually any structure that has a bend or fiber is declared evidence of life, for no clear reason. (This may be a trend, as PZ Myers basically made the same complaint of a previous Journal of Cosmology paper claiming to have found bacteria in meteorites)

If you can see four bacteria in this post, I will give you a prize*

If you can see four living things in this post, I will give you a prize*

This paper claims the images are of diatoms or diatom-like lifeforms, but they don’t show any as reference and their images aren’t magnified like most that try to show diatom structures.

A known diatom from Earth.

The authors also try really hard to link the alleged cells they see to alleged organisms responsible for the red rains in Kerala, India several years ago (those claims inspired similar controversy and seemed to rely on evidence that was only slightly more firm than what is offered here). If you’re going to make that connection, though, maybe you should show an image of that.

Aside from images, the only other data the paper mentions is a technique to measure the amount of elements in the sample. The paper only says the samples are high in carbon and oxygen, but don’t provide numbers.  They say that means what they’re looking at isn’t a mineral, but it’s worth pointing out there are in fact many meteoroids that are mostly carbon and oxygen so they might be looking at weird dust from those. That’s it; no attempt to extract any potential organic matter (though that’s also a dime a dozen in space, even without life).

The people at the Journal of Cosmology say other scientists are irrationally opposed to the idea that life on Earth may have originally come from outer space. While that’s not the dominant opinion in biology right now, it actually is something mainstream scientists are looking at. It’s just that, as Carl Sagan said, “extraordinary claims require extraordinary evidence”. And a bad SEM image is not the latter.

*The prize is my affection.

Real Stars Break Down Alcohol Through Quantum Mechanics, Not Their Liver

When most people think of astronomy, they think of physics. Many astronomers are technically astrophysicists, and even if that’s not their title, most have a physics background. (If you’re really in the know, you might know that planetary science is a distinct field that draws a lot on geology as well as astronomy.)  But another aspect of space science that’s grown a lot over the last decade or so is astrochemistry. Astronomers have been able to study chemical compounds in celestial bodies since the the middle of the 20th century, when radio telescopes could detect spectral emissions unique to certain molecules (both nearby and across the galaxy) and even more so when space probes could directly analyze celestial bodies in our solar system. But there’s also a lot of chemicals just out in the middle of space, and the list keeps getting longer and includes increasingly more complicated compounds. Astrochemistry looks at these chemicals and tries to understand how they could form in astronomical environments.

One of the bigger puzzles for astrochemists has been understanding how alcohols are formed and destroyed in space. Space is too cold for methanol to break up into the highly reactive methoxy radical in a way similar to most reactions on Earth. While UV radiation exciting molecules enough to break them apart can explain how some chemicals are formed (and why UV light gives you cancer), lab tests couldn’t detect methoxy after exposing methanol to UV radiation. Dust wasn’t even acting as a catalyst. It actually turns out the reaction works best when the methanol is in its gaseous form at low temperatures because those conditions are optimal for quantum tunneling.

The procession of a chemical reaction in normal, bulk circumstances (on the left) and via quantum tunneling (on the right). From Richard Helmich.

Tunnelingis a phenomenon that only occurs in quantum mechanics. There’s really no good analogy in the classical physics we’re most familiar with. To very quickly sum up, if an electron is in place A and can also be in place C, but A and C are separated by a region B where it shouldn’t be able to travel, it can sometimes still end up in C by tunneling through B. This is also generalized to more than just physical space. Tunneling means particles can do things they shouldn’t have the energy for, like the reaction picture above. Quantum mechanics just says that it won’t happen very often and it can take some time. This is where the low temperature comes in. As we’ve talked about before, temperature reflects molecular motion. At the low temperatures of open space, the methanol and hydroxide are moving relatively slowly. When they bump into each other, this means they won’t bounce off immediately, and in that longer frame of time, an electron is more likely to jump from the methanol to the hydroxide. It turns out this tunneling reaction is really efficient at lower temperatures: lab experiments showed methanol reacted 50 times faster at -210 degrees Celsius than at room temperature. The researchers are also confident that quantum tunneling can explain many other reactions in space.

You Can’t Name a Star, but You Can Name a Planet

If you’ve ever considered buying a star, let me give you advice: don’t. The International Star Registry, the major company that sells “naming rights” to stars, has no official power to do so and admits the name is only put in their own internal catalog, not any reference that astronomers use. In fact, the stars they name aren’t even visible to the naked eye. And considering that they have sold over 1 million named stars, we’re probably getting to the point where you need to make an investment in a good telescope if they’re keeping true to the promise of not renaming any stars.

So screw naming a star and go with something practical: name a planet that orbits another star (an exoplanet). The International Astronomical Union (IAU), the official body responsible for naming celestial bodies, has recently changed its procedures on naming exoplanets and their moons. Part of this was in response to an attempt to sell naming rights to a nearby exoplanet. The IAU pointed out that a naming process taking place completely outside it may have a winner that still doesn’t end up as the official name.  (They seemed particularly worried that people were paying money for this, even if it was a fundraising campaign for astronomy.) The campaigns were really popular, though, and the IAU seems to have decided that the public interest in these cases merits opening up exoplanet naming to the masses.

Currently, exoplanets just get an official scientific name based on the star they orbit. It’s not the typical science fiction standard where a planet’s name is the star it orbits plus a number representing what order it is from the star. Planets are still named after the star they orbit, but are named with lower case letters indicating the order of discovery, not the distance of the sun. So 55 Cancri e is closer to 55 Cancri than 55 Cancri b, but b was discovered first. The IAU’s new proposal doesn’t replace the technical names, but also creates official “common” names for public use.

Like all IAU naming systems, this one comes with a lot of rules. The big ones are that suggested names shouldn’t duplicate names of other bodies and they shouldn’t be commercial, offensive, or controversial. Other than that, the system is pretty open because the same rules as naming asteroids and dwarf planets apply. Those are pretty diverse, with names ranging from Ceres, Roman goddess of grain, to Einstein to Karl Marx. The system also specifies how groups that want to organize competitions to name bodies should do so: organizations should notify the IAU in advance, not collect revenue from the process, and inform the discoverers of the object.

One thing the IAU points out is that our understanding of discovered exoplanets is incomplete. In particular, there isn’t 100% certainty that each exoplanet that has been announced actually exists. Some of the detection techniques can give false positives, and though repeated observations are done before the discovery is announced to minimize that chance, it still exists. And it is also possible some planets may have been detected multiple times by different techniques. I wonder what would happen if the multiple discoveries had different names and were later revealed to be one.

If this really does catch on (and the IAU manages to quickly assign public names), I wonder how much theme naming would unofficially catch on in nomination. Would Sirius’ planets be doomed to dog and/or Harry Potter names? And I’m totally seeing someone trying to name a gas giant with multiple moons Polyphemus and one of its moons Pandora.

What’s interesting is the IAU note seems to cover more than just exoplanets and their moons. The title says “planets and planetary satellites” and nothing in the announcement specifies that the procedure only applies to extrasolar bodies. So this might mean that this applies to all future planet and satellite discoveries, even in our solar system. While we’re probably done with finding planets, astronomers expect to find more dwarf planets (though technically, as minor planets, they follow a different naming scheme than regular planets) and we keep finding satellites of both regular and dwarf planets. In fact, the IAU chose one of the names that won a contest to name one of Pluto’s two newly discovered moons.

A Day Without Satellites

The BBC has a short fictional piece about what would happen if all the world’s satellites stopped working. While that is unlikely, it’s an interesting look at how much satellites are integrated into everyday technology. For instance, while the Internet is mostly an Earth-based affair with undersea cables connecting continents, I didn’t know that that the atomic clocks on GPS satellites were used by data centers and Internet exchange points to timestamp Internet data packets. One thing I’m a bit confused by is how much the article claims international telephone calls would be disrupted. I could see things like aid workers and military units who are in areas with little landline or mobile infrastructure being affected, but I thought most international calls on landlines and regular cell phones were done through the undersea cable network.

While this article may be drastic, it is important to note that our satellites are increasingly at risk of damage and it’s an issue that increasingly concerns industry and governments.