From the Greek meaning 'heavy with wine'
A blog devoted to science and reason
Written after a glass or two of Pinot Noir.

Monday, December 23, 2013

Grandma Got Run Over By A Reindeer

Remember this Christmas song?
Grandma got run over by a reindeer
Walking home from our house Christmas eve
You can say there's no such thing as Santa
But as for me and Grandpa, we believe 
She'd been drinkin' too much egg nog
And we'd begged her not to go
But she'd left her medication
So she stumbled out the door into the snow 
When they found her Christmas mornin'
At the scene of the attack
There were hoof prints on her forehead
And incriminatin' Claus marks on her back

So I got to thinking. What would happen in a collision between a reindeer and an elderly woman.

While the song seems to imply that Grandma may have already been lying drunk in the snow and was then trampled by the reindeer, I’ll assume a more violent interaction. She was walking, and the reindeer, running down the road, hit her from behind.
Typical Diagram Drawn by a Physicist
The physics here involves the conservation of momentum. To simplify the problem, I’ll assume that the collision is like the one between billiard balls, what a physicist calls an elastic collision.

Momentum is the product of an object’s mass and its velocity.
A fundamental principle of the universe is that momentum is conserved; that is, this quantity of motion doesn’t change. It is mathematically expressed like this.
In collisions like ones with billiard balls, the total kinetic energy also is constant.
Let’s suppose this reindeer weighs 400 lbs. and was running at a speed of 45 mph. Let’s also suppose Grandma weighs 110 pounds and was walking at 4 mph.

With a bit of algebra we can find what happens to Grandma. It ain’t pretty. Grandma flies forward with a speed of almost 70 mph.
CREDIT: coolthings
Now about this family that let’s an old woman drink too much and then let’s her trudge all alone through the snow. 

Sunday, October 27, 2013

What Does a Physics Degree Get You?

Free food.

I woke up yesterday, and as I do everyday, I checked my email. There I saw that I had been tagged on FaceBook by Steve, a relative of mine. He posted the following:
Need some help from my academia family and friends! I need to present "in layman terms" how cold it would have to be outside to freeze 2 gallons of water @ -19ºC. 
Background: The product I sell has a moisture cured urethane in it and is activated by water. I am working in Canada where the lowest ever temp recorded was -60ºC (1947) so how long would it take to freeze a 2 gallon sprayer of room temp water which is about 10ºC at -19ºC. 
1st person that can explain it (so my block head can understand it) win's a perfectly smoked brisket delivered or shipped to "His or Her" home!!
Now he posted this at 5 am (7am Texas time), and I was still blissfully asleep. One and a half hours later, he wrote
So far my simple question is still unanswered! (Tick Tock) BTW when the west coast awakens my family physicist Vann Priest will have no problem with this so you all had better hurry!!
By the time I awoke at 8:30, Steve had already gotten some really good answers from Brian and Karen, so I was afraid I lost a chance at some Texas smoked brisket. I should make clear that Steve has this awful habit of posting his BBQ on FaceBook, and whenever he does, I drool all over my shirt. However, since he didn’t yet award it officially, I figured I might still have a chance.

A brief shout-out to Kevin who is quite an accomplished smoker. Kevin's brisket is also scrumdiddlyumptious, and I have been privileged to taste it on several occasions. It might be awhile before Kevin or I get another brisket though. He just became the father of twin boys.

So here’s my answer.

First the water has to cool to 0ºC. Newton’s law of cooling states that the rate at which the temperature of an object changes is proportional to the difference in temperature between the object and the environment. Fancy way of saying that if you want to cool something off really quickly, you put it in the refrigerator; if not, leave it in the kitchen.

Mathematically, Newton’s law is written

T is the temperature, t is time, TE is the temperature of the environment, and k is some constant. This is a straightforward first order differential equation.  The solution is

The problem though is that to find the time t we need to know both constants, k and C. There’s a lot of complicated physics that goes into k and C; however, to find C, we can set the time equal to zero. We know the initial temperature of the water and the environmental temperature. Punching a few numbers into my handy calculator gives me 3.37. We could do something similar to find k, but we would need to know the temperature of the water sometime later. I don’t have that information, so I can’t find the time it takes to cool down to freezing.

I’m not going to let that stop the analysis though. Once the water reaches 0ºC, it begins to turn into ice. The temperature stays at zero until all the water freezes. We can find how long it takes by knowing that the energy transfer happens by thermal conduction. Here’s the equation governing this phenomenon.

Q is the amount of energy that is being transferred (usually called heat), t is again the time, T is the temperature of the object through which the energy is being transferred, and x refers to the thickness of the object. There are two constants here too. A is the cross-sectional area of the object, and k (a different k) is called the thermal conductivity. (Once again, a lot of complicated physics rolled into a single number).

Here is a major complication. I can look up the thermal conductivity and figure out the area and the thickness.  The total amount of energy transferred in so problem; Q = mL where m is the mass of the water and L is the amount of energy required to change the state of the water per kilogram. But this differential equation is for one dimension only.  To do it in all three directions is some tough mathematics.

There’s no easy way to solve Steve’s problem.

Or is there?

I’m an experimental physicist. Let’s do the experiment. The freezer in most refrigerators is about -19ºC. Let’s put one gallon of water in the freezer and see how long it takes. The time it takes for 2 gal will be about twice as long.

Two hours into the experiment and the first thin layer of ice begins to form. In another hour, there’s a significant amount of ice. So Steve has about four hours before he needs to worry, and a Texas smoked brisket is on its way to California.

Thursday, October 10, 2013

Pooping Gold Bricks

Did that get your attention? As in my last post, this is a story of bacterial action. In this case, Kazem Kashefi, a microbiologist, and Adam Brown, an artist, used Cupriavidus metallidurans, a bacterium that can metabolize gold chloride.

Gold chloride, also called liquid gold, is a highly toxic compound. The bacterium is an extremophile, a microorganism that thrives in extreme conditions like extremely hot or cold climates or in toxic chemical conditions.

The gold that is extracted is pure, that is 24 karat. In the photo below, you see the gold particles. The largest one shown is about 1.5 millimeters wide; the smallest one is about the size of a human hair.

For more infromation about the art project, visit The Great Work of the Metal Lover.
CREDIT: Adam W. Brown

Wednesday, September 25, 2013

Aspartame is Not Made from Poop

CREDIT: NutraSweet

Once during my time as a science education consultant, the fourth grade class was experimenting with yeast. One of the experiments involved putting a burning wooden splint in a test tube containing yeast to demonstrate that the yeast produces carbon dioxide. I told the students that the carbon dioxide was yeast farts.

Now I made sure the children knew I was kidding, and we went on to discuss how the yeast converted sugar into CO2.

When I saw the headline Aspartame is made from bacteria feces, patent confirms, I first thought that some PR person or editor was trying to grab the readers attention and having a little fun at the same time. But after reading this article and others, I realize that the authors and their editors must really think that aspertame comes from bacterial poop.

I can think of only one reasonable response. BULLSHIT.

The above article links to another article that helpfully links to the original patent. In the patent it describes very clearly - it helps to know some biology - how aspertame is produced.

Microbiologists insert a short strand of DNA into a bacterium. This bit of DNA instructs the cell to produce the protein (Asp-Phe)n. This protein consists of the amino acids aspartic acid and phenylalanine. The scientists later cut this protein into smaller parts consisting of 2 aspartic acid molecules and 2 phenylalanine molecules and then market this as the artificial sweetener, NustraSweet.

So the scientists are taking advantage of the same cellular processes that your body uses to produce insulin, antibodies, cellular receptors, collagen, and enzymes. So if aspertame is made from bacterial poop then so are you.

When you eat proteins, your body breaks it down into the amino acids that compose the protein. So when you ingest Nutrasweet it breaks down into the the two amino acids. The only people who should not use NutraSweet are those who suffer from the genetic disorder phenylketonuria.  These people lack an enzyme that converts the amino acid phenylalanine into the amino acid tyrosine.

CREDIT: Fiskeren
But does this basic biology stop some from shouting "Danger ! Danger!"? Google "aspartame dangers" and you will come across the name Joseph Mercola. Check out QuackWatch's article on Mercola

A scientific statement on the safety of aspartame written by David G. Hattan, Ph.D., of the Division of Health Effects Evaluation at the Food and Drug Administration (FDA) is available from the FDA.

Monday, September 9, 2013

Why I Love/Hate Web 2.0

From the time I was born until I was about 16, my father owned a burger joint.  The Castle Burger. He opened every day at 11 am. For many of those years, I remember the local dentist, a nightclub owner, and two other men would take a booth and drink coffee for an hour or so.  They would sit there, sip on the coffee, and talk about current events.

That’s how much social commentary happened. Over a cup of coffee, a glass of beer, at the dinner table. Unbeknownst to everyone at the time that began to change in 1993.

That’s when the European particle physics lab, CERN, gave the world the World Wide Web.

I joined the Internet in the fall of 1994, and I created my first web page shortly thereafter. To do that, I learned some basic html at an American Association of Physics Teachers workshop and taught myself more advanced coding by examining the source code of pages I liked. Web page production became a hobby, and I changed the look of my pages almost annually – just because I could.

One had to be technically literate to create a page, or one had to have the money to have one created. The information was static and flowed one way – from the content creator to the viewer. For the most part, I think the Internet shared whatever credibility more established media enjoyed.

Then sometimes in the 2000s, the Web changed. We now had Web 2.0. Users became content creators without having to bother creating a web page.

Everyone could now contribute. MySpace and Facebook allows us to easily stay in touch; Wikipedia makes it easier for experts to share their knowledge; Tumblr, WordPress, and Blogger make it simple for anyone to share their thoughts.

The true democratization of the Internet.

I joined this democracy movement in April 2010. I created my FaceBook profile. I was motivated by my desire to reach out to my students at Rio Hondo College. I tell them what I think of them - they are the best students at Rio Hondo and they will be the best students at whatever university or college they transfer to, but despite their obvious interest and perhaps because of the times, they are not always aware of the scientific, engineering, and technological advances being made everyday.  I thought that I could do something to sneak in some learning.

Then I got a bit bored in July 2011. So one afternoon I signed into Blogger and started Oenobareus, my blog dedicated to science and reason written after a glass or two of Pinot Noir.

That is what I love. Both the blog and FaceBook let me share what interests me, and my expertise. Plus they give me a creative outlet. I try to be informative, occasionally funny, and every once in while, I let out some righteous anger.

Let me share some of my favorite blog posts:
Transformers 3 - Dark ofthe Moon: I applied some basic physics to calculate the gravitational effects of Cybertron on the Earth.
Don’t Ask Marilyn - parts 1 through 4: Marilyn vos Savant is a columnist in Parade magazine. In a 2011 column, she defends herself against a math teacher in a problem in probability. The post prompted several emails and three other posts where I patiently explain probability and entropy.
Santa Claus Science: Did you know it takes 11 million reindeer to pull Santa’s sleigh?
Flying Aircraft Carriers:Physics and Engineering in The Avengers: Another piece inspired by a movie. What I really enjoy about this piece is that I hope that students (and others) realize how one can do a quick calculation without sophisticated theories.
July 4th isHiggsdependence Day: Announcing the discovery of the Higgs boson. This was particularly fun as I have a brother-in-law named Higgs.
Twas the Night Before What?: A Newtonian twist on Clement Moore’s poem.
Au-some: There were many reports in the press how scientists had discovered the nuclear process by which gold was created. What I like about this one is I really had to delve into the literature. Nowhere in the article was gold mentioned.
These are some of my favorites, because I was sharing my expertise.

Why do I hate Web 2.0?

It all started late in 2011. I received a friend request from Aaron, an acquaintance of a former student. He stated he was interested in intellectual discussions. As it turned out he was a libertarian, anarchist, christian, young earth creationist.

I made a smart-ass comment about Bristol Palin when Aaron asked how to end teen pregnancy. That led to me educating myself on the issue and my post Making Babies. Which led to You keep using that word. I do not think it means what you think it means.

And thus began my intense dislike for Web 2.0.

Through Aaron I found True Dinos, a Facebook profile of a Texas fellow who like dinosaurs. This young earth creationist (YEC) witnessed a pterosaur when he was 11 years old.

It was at True Dinos that I ran across Cowboy Bob Sorensen and The Question Evolution Project.

Here’s what you need to know about TQEP:

Welcome to "The Question Evolution Project". This is a resource that points to information showing the failings of evolution. We are also here to encourage people to speak out against evolutionary indoctrination.

Evolutionism dominates the media, education and so on. Pages like this are "equal time" to present information that is ignored and often suppressed. We attempt to help raise awareness that true science is not afraid to examine contrary evidence and allows alternative theories to the interpretation of the evidence (such as creation science). Specifically, evolutionists should not have the right to shout down, censor, censure or intimidate creationists / ID proponents.

I first earned the ire of Cowboy Bob, a biblical literalist, by insisting he confront his hypocrisy. I asked him if he was a geocentrist. Bob blustered about suing me for posting screenshots from FaceBook.

I mocked Bob after that by finding a photo of him and attaching this description: “Bob has read one book. It has made him an expert in biology, geology, physics, and chemistry.” Nine months later, Bob filed a Digital Millenium Copyright Act complaint and the photo was removed from FaceBook. But not for long.  I filed a counter-notification and a few weeks later, access was restored.

Another character is Kirk Hastings. Kirk has a few FaceBook profiles: What is Truth?, Freedom From Atheistic Scientism, and The Question Irreligiosophy Project. Kirk has a habit of pasting quotes. I came across one that I had to investigate.
Radio telescopes, linked with computers, simultaneously search millions of radio frequencies for a nonrandom, nonnatural, extraterrestrial signal—any short sequence of information. Yet, the long sequence of information in the DNA of every living thing on Earth is a signal from an intelligence—a vast intelligence—a Creator. Almost all those searching for extraterrestrial life believe it evolved naturally in outer space. If they ever accepted the DNA evidence for a Creator, the evolutionary basis for their search would disappear.
He credits a journalist for the journal Science and helpfully cites the volume, date, and page number.

I downloaded the article and searched for the quote. Even after calling him out for his dishonesty, he continued to claim that he was accurately quoting the journalist and insisted the quote from the very article I had in my hand. Only very recently has he deleted the post from his timeline. I’ll take that as an admission of guilt.

There is no shortage of creationists to joust with. There are also plenty of cranks out there who are willing to engage. Stupid politicians will continue to provide comedy gold as well as provoke anger.

But I reserve a special enmity for commenters. Even before Web 2.0, I never understood call-in radio shows, interviews with the person on the street, and the like.

Commenting seems to bring out the very worst especially behind a wall of anonymity. Just this past Friday night, the CBS affiliate aired a story that hits me rather personally.

For thirteen years – up to 2011 – I worked with students and teachers at a private elementary school. I coordinated the science program, developed science lessons with the teachers, and taught all levels from pre-school to 8th grade. Until you’ve been in a classroom with these teachers, it’s hard to appreciate the job they choose to do.

So it was with deep sadness that I read this story. If true, a teacher violated the trust of a student, the parents and his co-workers.  If false, a man’s career is sidelined and his reputation is ruined. The article states that the teacher is forbidden by the California Department of Social Services from having any contact with any children in any facility licensed by the department. The Whittier police department closed its investigation and the District Attorney is not filing any charges

Let me read you some of the 863 comments [as of 9:20 am, Sept. 8.] These are not necessarily the worst of them.
  • Should have identified the despicable deviant teacher by name.
Typical MSM and Union rats at work.
  • Oh good, another liberal sicko exercising its uninvited deviant sexual desires on others, and once again, on a child. When liberals are not busy murdering children, or making it easier for others to murder children, they are busy molesting the children. They call it, "being progressive".
  • No wonder he got in trouble...
He didn't say "Obama says".
  • KILL the perv!
  • On one hand you have the government brainwashing your children with communist ideologies and on the other hand they are being molested by these freaks. If god doesn't deal with these vermin then the people will. Soon. VERY soon.
  • Another liberal pedophile who we have teaching our kids.He needs to be swinging from a tree at the end of a rope.
  • sounds like black to me.
  •  If I remember correctly, all pedophile teachers are sent to Kalifornia to teach. Kalifornia does not discriminate based on sexual preference. The zoophiles are sent there as well. What a wonderful inclusive place to raise a family.
  • Not only are the Public School "teachers" Lefty Lemmings but they are also Pedophiles.
  • I've never known a male to work as a preschool teacher.
  • If it were a male of European decent or a Christian of any decent they would have blasted the face and name everywhere. I am gonna bet it was either a homosexual or a minority.
  • Its now open season on Johnny's fartbox. Homosexual Sodomite Pedophiles are going to be raping children all over this nation this school year. You get what you voted for.
  • only anal tongue darts are acceptable in California

And with that, thank you for letting me get all this off my chest.

Sunday, August 25, 2013

Are You Smarter Than an 8th Grader?

You have probably already seen this test; it's been all over ABC News, FaceBook and has been emailed back and forth. It comes courtesy of the Bullitt County History Museum.

On the museum site with the test's answers, the curators warned that
obviously it tested some things that were more relevant at that time than now, and it should not be used to compare student knowledge then and now.

However, it's quite clear not everyone has read this advice. Here are some comments from the Huffington Post:
  • For all the arm chair critics, what this shows is how far our expectations have fell.
  • What this test shows is how low our expectations are for what children ought to know today.
  • You feel threatened by this test because it shows how lacking our education system is.
  • They valued education much more than people do today.
  • This test reflects a decided dumbing down of the US population to my mind.
By the way, can anyone find the grammatical error in the first comment?

[Scroll down.]

To these critics, I say
Here's one thing that California 8th graders are expected to do in math.
Students use linear equations and systems of linear equations to represent, analyze, and solve a variety of problems. Students recognize equations for proportions (y/x = m or y = mx) as special linear equations (y = mx + b), understanding that the constant of proportionality (m) is the slope, and the graphs are lines through the origin. They understand that the slope (m) of a line is a constant rate of change, so that if the input or x-coordinate changes by an amount A, the output or y-coordinate changes by the amount m ⋅ A. Students also use a linear equation to describe the association between two quantities in bivariate data (such as arm span vs. height for students in a classroom). At this grade, fitting the model, and assessing its fit to the data are done informally. Interpreting the model in the context of the data requires students to express a relationship between the two quantities in question and to interpret components of the relationship (such as slope and y-intercept) in terms of the situation.
From the reading standards for information:
Determine the meaning of words and phrases as they are used in a text, including figurative, connotative, and technical meanings; analyze the impact of specific word choices on meaning and tone, including analogies or allusions to other texts. 
From the writing standards:
Conduct short research projects to answer a question (including a self-generated question), drawing on several sources and generating additional related, focused questions that allow for multiple avenues of exploration.
From the speaking and listening standards:
Delineate a speaker’s argument and specific claims, evaluating the soundness of the reasoning and relevance and sufficiency of the evidence and identifying when irrelevant evidence is introduced.
From the language standards:
Use knowledge of language and its conventions when writing, speaking, reading, or listening.a. Use verbs in the active and passive voice and in the conditional and subjunctive mood to achieve particular effects (e.g., emphasizing the actor or the action; expressing uncertainty or describing a state contrary to fact).
I could go on with the literacy standards for history, social studies, science, and technical subjects, but I won't. I'll get to my point.

People often confuse knowledge with intelligence. Knowing what the name of the climate zones is still important, especially today with the rate the climate is changing, but knowing those zones is useless out of context; that is, unless you're appearing on Jeopardy or playing a bar trivia game.

Smart people know a lot of stuff, but smart people know what do do with that information.

Sunday, August 18, 2013

Kirk Hastings' Pants Are on Fire

CREDIT: PhotoBucket

We last saw Kirk Hastings when he wrongly accredited some creationist mumbo-jumbo to a respected science journalist. He has yet to correct the FaceBook page Freedom From Atheistic Scientism. Isn't there a word when a person makes a claim he knows to be false?

This is not the only time Kirk has distorted the truth, but first let me insert here my thanks to Question Kirk Hastings, a FaceBook page dedicated to documenting Kirk. 

Here is Kirk quoting Colin Patterson, a paleontologist affiliated with the British Museum and a Fellow of the Royal Society.
Out of context that statement might seem to express doubt in modern biological theories. However, when one reads that statement in context, it takes on a whole new meaning.
Gillespie's book [Charles Darwin and the Problem of Creation]is a historian's attempt to explain the amount of space that Darwin gave to combating the creationist arguments. Gillespie shows that what Darwin was doing was trying to replace the creationist paradigm by a positivist paradigm, a view of the world in which there was neither room nor necessity for final causes. Of course, Gillespie takes it for granted that Darwin and his disciples succeeded in this task. He takes it for granted that a rationalist view of nature has replaced an irrational one and of course, I myself took that view about eighteen months ago. Then I woke up and realized that all my life I had been duped into taking evolutionism as revealed truth in some way. 
Furthermore, Patterson gave the "fairly rumbustious talk" that this statement came from at an informal meeting dealing with systematics (classification).  In a letter, Patterson wrote "my talk was addressed to professional systematists, and concerned systematics, nothing else."

One more example of taking something out of context. Here Kirk repeats a statement from a radio and YouTube commentator.
What did Stephen J. Gould really write? 
The fossil record with its abrupt transitions offers no support for gradual change. All paleontologists know that the fossil record contains precious little in the way of intermediate forms; transitions between major groups are characteristically abrupt.
 How does Gould feel about being quoted in such a dishonest manner?
Since we proposed punctuated equilibria to explain trends, it is infuriating to be quoted again and again by creationists -- whether through design or stupidity, I do not know -- as admitting that the fossil record includes no transitional forms. The punctuations occur at the level of species; directional trends (on the staircase model) are rife at the higher level of transitions within major groups.
I find it funny that this example is used on Wikipedia as an example of quoting out of context.

What does Kirk have to say for himself. On a different FaceBook page he administers, The Question Irreligiosophy Project, he writes
Creationists can make mistakes like anyone else, and I haven't seen that they generally have any problem correcting them when necessary (after all, they believe the Bible when it says "You shall not lie"). 

Lest I be accused of lying, here is the screen shot.

Saturday, August 17, 2013

Is a Pesticide a Dietary Supplement?

Those dietary supplements you take have all been shown to do what they claim, right? Plus, they've been shown to be safe to consume, right? No one would market what they know or suspect might be harmful, right?

No, no, and no.

The Food and Drug Administration (FDA) has regulatory power over drugs, and drugs are "intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease" and include "articles (other than food) intended to affect the structure or function of the body." 

The Dietary Supplement Health and Education Act (DSHEA) essentially forbids  the FDA from acting against manufacturers of dietary supplements. Senators Tom Harkin (Iowa) and Orrin Hatch (Utah) were the primary sponsors of the DSHEA.

Supplement makers use the following disclaimer:
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
I put this text in the smallest font possible, because that's often how one finds it. Here it is in a more readable font size.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
One supplement provider, Matt Cahill, is going to jail for the death of 17 year old Leta Hole. Sorry, that's incorrect.  He pled guilty for mail fraud and "introducing a misbranded drug into commerce." He spent two years in federal prison. 

Chemical Structure of DNP
The drug he misbranded was 2,4 Dinitrophenol or DNP.  It is used in the production of pesticides and explosives. It was used as a dieting aid in the 1930s, because it increases metabolic rates, but DNP was quickly recognized for its toxicity.

Just months before beginning his prison term, Cahill started a new company and began selling a steroid he marketed as Superdrol. Superdrol contained a steroid Cahill found in a book. Cahill said that Superdrol was safe and felt qualified to make that determination.

What qualifications does he have?  "I had a scientific background in school, I just don't have a degree." He says he was enrolled for a time in an exercise physiology program at Nassau Community College, but can't remember taking any chemistry classes. The sales of Superdrol provided a tidy income while he was in jail. He later sold Superdrol to another supplier, and Jareem Gunter was banned from NCAA competition and needed a new liver.

Cahill is now facing charges of "introduction and delivery of unapproved drugs into interstate commerce" for Rebound XT.

Never letting federal charges get in his way, Cahill has "tons of great formulas," and has introduced Craze. Craze was listed by bodybuilder.com as New Supplement of the Year in 2012 and a nominee of 2013 Pre-Workout Supplement of the Year, but Craze is currently unavailable from the website's store.

What does Craze have in it? A traditional Chinese medicine called dendrobrium, a type of orchid; however, authorities are questioning whether the ingredients are as natural as claimed. Swedish scientists tested Craze and found substances that are chemically related to amphetamine. 

Meanwhile, the money continues to roll in.

NOTE: The primary source of this post if the USA Today investigation into Matt Cahill

For more information on the shame that is the DSHEA, see Quack Watch and Science-Based Medicine.

Thursday, August 8, 2013


This past month there have been numerous stories about how all the gold in the universe was created.  Just google "gold neutron star", and you'll see what I mean. So being me, I wanted to read the original research: An R-Process Kilonova Associated with the Short-Hard GRB 130603B, E. Berger, W. Fong, and R. Chornock of the Harvard-Smithsonian Center for Astrophysics. (1)

I first gave it a cursory read. I couldn't find a mention of the creation of gold anywhere, so I took advantage of technology and used the Find command in my browser. Nothing there, but then I realized why. Someone at Harvard must have written a press release, and in order to get the media interested in the research - which is legitimately important - they  made it sexy and what is sexier than gold.

So I sat down to read the kilonova paper carefully. I didn't have to read far before I read the phrase r-process and Justin Huang's graduate level nuclear physics class came to mind. [Although r-process is in the title, my mind didn't click in until later.]

First some background for those of you not nuclear or astrophysicists. After a microsecond, protons and neutrons formed and couple of minutes or so later, the universe had cooled enough for primordial deuterium, and helium nuclei to form.  Many years later, 379,000 actually, electrons combined with these nuclei to form atoms. It wasn't until a hundred or so million years that stars began to shine.
CREDIT: Atmospheric Imaging Assembly (AIA 304)
of NASA's Solar Dynamics Observatory (SDO)

Fred Hoyle and his colleagues in a classic paper (2) showed how the elements other than hydrogen and the primordial helium were created. I won't go into a long explanation of stellar evolution, but the elements up to iron were created by nuclear fusion. The Sun is fusing two hydrogen nuclei into a helium nucleus and this process releases a lot of energy (we call it sunshine). I'm oversimplifying here, but when the hydrogen in our Sun is depleted in about 5 billion years, it will start to fuse helium. When the helium is gone, our star will be a very hot ball of carbon and oxygen. The Sun will be a white dwarf - basically a very large and very hot diamond in the sky. 

Stars more massive than the Sun will keep fusing and shining up to the point where iron is formed. The process stops there because to fuse iron and elements heavier than it requires an input of energy.

If you now look at a periodic table, you should wonder where did all the other elements like gold come from. There are two processes that are responsible for these heavy elements: the r (rapid) and s (slow) processes. The s-process cannot create elements heavier than lead and this method occurs in old giant stars. 
The Periodic Table of the Elements with hydrogen, helium, iron, and gold highlighted.
Hoyle et al. suggested that the r-process occurred in type II supernovae. This sort of supernova comes about when the thermal motion of the nuclei is not enough to counteract the effect of the star's self-gravity. The core of the star collapses and the outer layers are violently ejected. Depending on the initial mass of the star, the result of the core collapse is either a neutron star or a black hole.

The problem with this hypothesis is that given the abundance of the elements either most supernovae did not expel much matter or that supernovae ejects only a small amount of the material. Given the intensity of a type II supernova, either possibility seems unlikely.
The Crab Nebula, the aftermath of a supernova.
One possibility was the collision of neutron stars (3), and here we're back to the kilonova paper. Berger and his co-workers present evidence of "the presence of excess near-IR emission matching the expected brightness and color of an r-process powered transient (a kilonova)" and the inferred mass ejected during the collision "matches the expectations from numerical [neutron star] merger simulations."

My head exploding.
CREDIT: Gil Thorpe
Look at that ring on your finger or the chain around your neck. Then imagine two neutron stars colliding. 

(1) An R-Process Kilonova Associated with the Short-Hard GRB 130603B, E. Berger, W. Fong, and R. Chornock, http://arxiv.org/abs/1306.3960v2.
(2) Synthesis of the Elements in Stars, E.M. Burbridge, G.R. Burbidge, W.A. Fowler, and F. Hoyle, Reviews of Modern Physics, Vol. 29, No. 4, pp. 547 - 650 (1957).
(3) R-Process in Neutron Star Mergers, C. Freiburghaus, S. Rosswog, and F.K. Thielemann, The Astrophysical Journal, Vol. 525, No. 2, pp. L121-L124 (1999)

The United States Bullion Depository, Fort Knox, KY, shown here in a scene from the James Bond movie Goldfinger.
CREDIT: United Artists/Eon Productions