At a panel on atheism and science, there was a question about why proportionally so few women pursue careers in the hard sciences. The question relates to comments from Larry Summers about whether there is perhaps some neurophysical explanation for the difference between the genders in this area.
Astrophysicist Neil deGrasse Tyson stepped up with a fantastic response, based upon his own experience having to deal with all of the challenges of being a minority in a white-dominated field of study. Though Tyson has never been a woman, he's always been black, and the challenges are somewhat similar in the sorts of hurdles they have to jump. Here's the link to the segment on YouTube (though if you want to back up and watch the whole video, that's fine too).
Of particular interest, though, is Tyson's observation that he looks behind him and laments the overall lack of progress in getting minorities engaged in the hard sciences. Where are the people coming up in his wake, benefiting from the challenges he's had to face and overcome? To be sure, Tyson is not the only black scientist ... not even the only prominent black scientist. Just within theoretical physics, James Sylvester Gates and Clifford Johnson come to mind as not only great scientists, but also great science communicators. (Gates is actually about 8 years older than Tyson and Johnson is English.)
Many of the challenges that these men have had to face are, sadly, still in place even today. Dr. Tyson recounts an experience, for example, where he was targeted for investigation when store alarms went off. One has to wonder if he was perhaps targeted because of his spiffy astronomy-themed vest or because they were concerned that he had stolen Magnum P.I.'s mustache.
So, Tyson concludes, before we begin looking for biological explanations for different demographic representations in the sciences, we need to be sure that the social explanations are completely ruled out.
This panel is from several years ago, but it just got bumped to my attention through a viral treatment through the Upworthy website.
Image: Dr. Neil deGrasse Tyson, astrophysicist, at a 2005 meeting of the NASA Advisory Council in Washington, DC. Public Domain from NASA
Well before tax day comes around, the federal government already has a pretty good idea how they're going to spend the money. In an effort to make at least token steps toward transparency, the White House website has released a website called Your 2013 Federal Taxpayer Receipt. This website allows you to enter your Social Security, Medicare, and Income Tax amounts and find out how much of your federal tax bill went to various aspects of the federal budget.
Even without entering values, though, the distribution is telling. The category Space, Science, and Technology Programs comes in at a whopping 1.13% of the federal budget, which is broken down between:
- NASA: 0.64%
- National Science Foundation and additional science research and laboratories: 0.49%
There are some other line items, buried within other categories, which might arguably contain various science-related expenses:
- National Defense - Research, development, weapons, and construction: 7.60%
- Health Care - Health research and food safety: 1.43%
- Natural Resources, Energy, and Environment 1.92%
And, of course, some percentage of the education-related expenses no doubt go to science education. Excluding the defense-related research, this means that the total of all of the scientific research is - at the absolute maximum - 4.48% of the federal budget. And, in truth, most of this 4.48% goes to aspects of these categories that have nothing to do with actual research.
These funding concerns are at the heart of many of the essays in Space Chronicles: Facing the Ultimate Frontier by Neil deGrasse Tyson. For example, even the 0.64% of the federal budget attributed to NASA is wrong to think of as scientific research-oriented. According to Tyson:
When NASA's manned missions are not advancing a space frontier, NASA's science activities tend to dominate the nation's space headlines, which currently emanate from four divisions: Earth Science, Heliophysics, Planetary Science, and Astrophysics. The largest portion of NASA's budget ever spent on these activities briefly hit 40 percent, in 2005. During the Apollo era, the annual percentage hovered in the mid-teens. Averaged over NASA's half century of existence, the annual percentage of spending on science sits in the low twenties. Put simply, science is not a funding priority either for NASA or for any of the members of Congress who vote to support NASA's budget.
If NASA's budget devotes only about 40% toward research, and if this is optimistically similar for other science-related sections in the budget, then it's safe to say that my earlier 4.48% prediction is going to come out to be even less than 40% of that ... or less than 1.78% of the federal budget devoted to non-defense scientific research!
If you're reading this blog, then this likely isn't that much of a surprise to you, but it never fails to amaze me how many people I run into who think that scientific research receives lavish bundles of money handed out by the federal government.
But the lesson from this budget is absolutely clear: aside from defense-related research, an incredibly small percentage of our federal budget is devoted toward investment in scientific research.
Leonard Susskind's phenomenal book The Theoretical Minimum: What You Need to Know to Start Doing Physics is slated for a paperback release on April 22, 2014. For anyone who seriously wants to confront the challenge of actually doing physics - instead of just learning about all the cool stuff that physics talks about - this is really an essential book. Every student who has any hope of moving forward into the study of physics or engineering would do well to have this book on their "to read" list. The strong presence of mathematics isn't for the faint of heart, but it's a level of mathematics that anyone with an interest in physics or engineering will need to become familiar with. (See "What Skills Do I Need to Study Physics?")
The sequel, Quantum Mechanics: The Theoretical Minimum, came out at the end of February. A review on it is coming soon ... but if you haven't read the first book yet, then your chance to get it in paperback is coming up.
Ever since reading Jim Kakalios' The Physics of Superheroes, I've been intrigued with the science of how superheroes do the things they do. While this usually manifests in the more grandiose elements of the superhero world, with questions like "How can Iron Man fly?" or "What all can Magneto manipulate with his magnetic powers?" it can show up in much more mundane places as well.
Toward that end, the fine folks over at Wired magazine's Dot Physics blog have taken a commercial segment where Captain America catches his thrown shield and turned it into a problem that incorporates friction, Newton's third law of motion, and the principle of conservation of momentum toward an entirely worthy goal: determining the mass of Cap's shield.
The process is available on their blog, along with some nice little free-body diagrams. For those who don't want to work through the calculations, though, the results come out to the shield having a mass of about 19.9 kg. This means a weight of about 43.9 pounds, which is a pretty heavy shield and certainly hefty to throw, though probably not for someone enhanced with super-soldier serum.
The author then goes a step forward to consider the density of the shield, and here I think we run into some problems. Using some additional estimates, he arrives at a pretty broad range: 87 8767 - 4383 kg/m3. This range extends from a bit more dense than iron to less dense than titanium, so it is a reasonable range, in principle, but the Vibranium alloy that composes Cap's shield may give some additional clues. Here is from The Physics of Superheroes on the subject:
Wolverine's claws are composed of pure Adamantium, but Captain America's shield is a one-of-a-kind alloy of steel and Vibranium. The steel is needed to provide rigidity, so that the shield can ricochet off walls and supervillain minions. Vibranium is an extraterrestrial material brought to Earth when a meteorite crashed in the African nation of Wakanda, which is ruled by the superhero the Black Panther. Vibranium has the ability to absorb any and all sound and convert the energy in the sound wave into some other, not-well-specified form, making it the perfect shock absorber, a quality strongly desired in a shield.
Kakalios doesn't specifically address the density of Vibranium, but I find it unlikely that something with the ability to absorb sound waves would be more dense than iron, so my guess is that this would at the very least be at the lower end of this spectrum. In part this seems justified because the special properties of the Vibranium alloy would indicate that we can stick with the thinner shield estimate and still have an effective shield.
What do you think? Does that shield look like it weighs over 40 pounds?
The scientific television event Cosmos: A Spacetime Odyssey has aired three of its thirteen episodes so far, and I, for one, am extremely impressed with what I've seen. When the series began, I asked if it could really live up to the hype and I'm fairly sure that it's at least coming close. Though the core science in each episode is well established and won't be new to anyone who has studied science to any depth, it is presented in an engaging and entertaining manner that makes it accessible even to viewers who may never have been exposed to the concepts before. For those of us who know the basic facts, it's still good television. The historical treatments and little details sprinkled throughout offer enough insights that I've discovered a couple of new things in each episode. Again, I cannot commend FOX enough for the risk they took in embracing this project, and I truly hope it is successful and shows television executives that thoughtful television does have an audience in America.
If you haven't yet seen the series, then I do recommend that you check it out. If nothing else, this will at least help offer solidarity in support of intellectually-stimulating television programming!
- Episode 1: Standing Up in the Milky Way
- Episode 2: Some of the Things that Molecules Do
- Episode 3: When Knowledge Conquered Fear
Let us know what you think of Cosmos: A Spacetime Odyssey in the comments below!
Physicists have detected gravity waves in the light left over from the Big Bang, which hints that a 30-year-old cosmological theory that potentially bridges the divide between the largest and smallest scales in our universe might be on the right track.
For decades, scientists have widely accepted the Big Bang theory as the leading cosmological description of the universe's earliest moments. The real nail in the coffin of alternative theories was the discovery of the cosmic microwave background (CMB) radiation in 1964, which matched closely with the theoretical predictions about the existence and value of this remnant energy left over from the earliest universe.
But this most certainly did not mean that all questions about the early universe had been answered. As more data came in from astronomers, it became clear that the universe had properties which cosmologists would like to explain, but which were not specifically determined by the Big Bang theory itself. How to explain, for example, the fact that the universe looks roughly the same in all directions (called the homogeneity problem). Or how could they explain the fact that the spacetime geometry appeared to be so flat (called the flatness problem)?
In 1980, the particle physicist Alan Guth took a stab at this problem. Together with colleagues, he worked to apply cutting edge understanding of the quantum physics at work at the smallest scales of reality to figure out what might have been going on in the early universe. The result was a prediction that the early universe would have been incredibly unstable and, within the first second of the big bang, would have undergone an immense expansion. The resulting theory became known as inflation theory and in the three decades since, it has become widely accepted among physicists of all stripes.
Part of the reason for this is that all evidence we've gathered from observational projects such as WMAP and others have supported the predictions of inflation. But there were, in fact, some other suggestions that might have explained these different phenomena as well. So while physicists broadly believed that inflation was probably true, they didn't yet have a key piece of direct evidence to confirm it over and above the rival theories.
Fortunately, inflation theory did offer a very precise prediction that was offered by no other competing theory. During the rapid expansion in the earliest instance of the universe, the very fabric of spacetime itself would have been distrubed, sending undulating ripples throughout the universe itself. These gravity waves (called the Cosmic Gravitational-Wave Background or CGB) would be incredibly difficult to detect, but the theory predicted that they would result in a polarization of the cosmic microwave background itself ... and inflation theory also predicted precisely the level of polarization that was expected!
All that was required was for technology to catch up with theory and become refined enough to detect whether or not this polarization existed. On Monday, March 17, 2014, the BICEP2 collaboration group announced results that confirmed the first direct evidence of inflation theory. Using advanced telescopes mounted at the South Pole, they detected precisely the polarization predicted by the inflation theory. Specifically, they detected that the CGB had a B-mode polarization with a value of r = 0.2.
This is being broadly heralded as confirmation of the inflation theory, although I should be quick to point out that it would need to be confirmed by other experiments. Fortunately, there are several in place to do just that. If confirmed, however, it would seem to be about as solid confirmation as a theory could have, so inflation theory will become even more widely accepted within the physics community. This evidence represents the earliest evidence we've found about anything that happened in our universe and, in the words of physicist Clifford Johnson's Asymptotia blog:
Those tiny scales are knocking on the door of the kinds of things I work on - quantum gravity. The very young universe had both quantum physics and spacetime physics (gravity) doing important things together and the combination of the two "quantum gravity" is what we hope to understand and put to the test one day, whether it be string theory or some other approach we may or may not have thought of.
Though there's likely not going to be any practical application to this discovery, this sort of confirmation is definitely the sort of thing that could set Alan Guth and the other creators of inflation theory on the track for a Nobel Prize. Amazingly, we have possibly one of the most fascinating historical records if that is the case. One of the physicists working on the experiment notified Andrei Linde (one of the co-creators) of the discovery ... and recorded it. If confirmed in the next couple of years, we therefore have the possibility of the first Nobel Prize in Physics that was heralded in with a viral YouTube video!
Image: A timeline of the history of the universe. (June 2009), Source: NASA / WMAP Science Team
- Harvard-Smithsonian Center for Astrophysics - "First Direct Evidence of Cosmic Inflation" (official press release)
- ArXiv.org - "BICEP2 1: Detection of B-mode Polarization at Degree Angular Scales" (abstract and full article)
- Symmetry Breaking - "Physicists Find Evidence of Cosmic Inflation"
- Asymptotia - "Discovery Clarification"
- NPR 13.7 Blog - "A New Window on the Big Bang Has Been Opened"
- Video of cosmologist Sean Carroll discussing the discovery on PBS Newshour
- Video of Andrei Linde being informed about the confirmation
If you have any interest in science, there's a good chance that you've been as excited as I am to see the new series Cosmos: A Spacetime Odyssey, premiering tonight on Fox and National Geographic Channels. This series is a sequel or reboot, depending on how you look at it, of the classic 1980 Cosmos series hosted by Carl Sagan, widely lauded as one of the most influential television shows - and certainly one of the most influential science shows - of all time. The new series is being hosted by Neil deGrasse Tyson, who has somewhat taken over Sagan's reigns as the premiere science communicator to the American public, but early reports are that the show definitely lives up to its namesake.
My own review of the show will be coming up tomorrow, because I have to wait for it to become available through a streaming service (probably Amazon Prime, unless it's rebroadcast on Hulu). Have you seen the premiere episode of the new series yet? What did you think of it? Give your opinion in the comments below.
One of the key things scientists understand is that data has to be viewed within its proper context.
Consider the recent results of a National Science Foundation study (Science & Technology: Public Attitudes and Understanding). A very troubling statistic has come out of this report:
1 in 4 Americans doesn't realize that the Earth revolves around the Sun
It's hard not to view this fact with alarm. In the years since Galileo Galilei, the heliocentric model of the solar system has been widely accepted. Isn't it incredibly alarming to think that one-fourth of Americans don't know this basic astronomical fact?
Now consider this response in context: Europe and other nations did far worse! Only two-thirds of European respondents got the question correct. (Looking at table 7-8 in the report, it's clear that we were about on par with responses from India and Malaysia, though South Korea did much better on this question.)
So, yes, the fact that one-fourth of Americans appear to believe in the geocentric model of the solar system is problematic and troubling ... but looking at the data overall (again, table 7-8), we see that America's knowledge of basic scientific facts exceeds the most recent data from other countries around the world.
There is even hope for science's role within the culture war! Americans got very low scores on knowledge about the Big Bang and human evolution, but more detailed analysis of the data shows that this is not actually a sign of scientific ignorance. As the Highlights from the report explain:
A survey experiment showed that 48% of respondents said they thought it was true that "human beings, as we know them today, developed from earlier species of animals," but 72% gave this response when the same statement was prefaced by "according to the theory of evolution." Similarly, 39% of respondents said that "the universe began with a huge explosion," but 60% gave this response when the statement was prefaced by "according to astronomers."
In other words, when asked what science tells us, the responses are on par or better than the responses of the other nations. A majority of Americans are aware that scientists believe in the Big Bang and human evolution. The problem is that, in these areas, they don't believe what science tells us about the history of the universe and our species. (See my previous post about the flaws in this thinking.)
So it does seem like we're doing a good job in distributing the knowledge of scientific facts. The key is imparting the understanding that these "scientific facts" are actually, you know, facts.
Physicist Max Tegmark has a remarkable hypothesis: that the ultimate form of our physical reality is a mathematical structure. In his new book, Tegmark gives an incredibly lucid account of the current physical understanding of our universe at the largest level of cosmology and also at the smallest level of individual particles and quantum physics. The result is his mathematical universe hypothesis, and the even more astounding suggestion that there exists an entire multiverse of parallel universes representing entirely different mathematical structures.
Touching on our deepest yearning to answer the question "What is reality?," Tegmark's first book for a popular audience does not assume any deep understanding of current physics, but by the end will lead you to the very limits of what we might expect reality to be like.
For more, see our full review of Our Mathematical Universe: My Quest for the Ultimate Nature of Reality.
It is easy to casually disagree with someone and dismiss most of what they say, especially when they're almost entirely wrong. That is the tactic that most science sources have used in responding to the recent "great debate" between Bill Nye (the Science Guy) and creationist Ken Ham, which took place earlier this week. However, I think it's far more fruitful to explore the valid points made by the creationist side of the argument, which point us toward a deeper understanding of how and why science actually does work.
The rather lengthy debate is available for viewing online and the point under consideration was:
Is Creation a viable model of origins in today's modern scientific era?
This was not a debate over the existence of a creator deity in general, but of a specific, 6,000-year-old creation scenario. Ken Ham is a young Earth creationist, the president of Answers in Genesis and the Creation Museum. He believes that God directly created the universe, the Earth, humanity, and all other life on Earth about 6,000 or so years ago, following a literal interpretation of the Biblical story of Genesis.
It would be easy to anticipate that we could just dismiss him, but he's clearly an intelligent guy and has spent much time formulating his explanations to justify his belief system. And it might surprise you to learn that (in my opinion, at least) he made a number of extremely valid points.
The Role of Assumptions in Science
I'd like to focus my attention on one of Mr. Ham's core tactics: distinguishing between observational/experimental science and origins/historical science. His argument in this regard is that in order to construct a theory of origins, scientists have to make assumptions, and that these assumptions must, by necessity, move beyond the observable evidence.
And, as formulated above, it's certainly a valid statement. The current age of the universe, of the Earth, and of the various animal species located on it is calculated as ancient using a variety of assumptions, and these assumptions can not (and should not) be beyond question.
For example, one of my major objections to a young-Earth creationism from a physics standpoint has to do with the speed of light. One of the key discoveries of the last century of physics is Albert Einstein's theory of relativity, which dictates that light photons always move at the same constant speed in a vacuum. We know this speed, and there are various astronomical methods (which are widely accepted based upon our understanding of physics) for calculating the distances to stars. Using this, we know that when we look at stars, then we are actually looking at that star as it looked in the past ... however many years ago the light left the star, which can be calculated using the distance and the speed of light. We know that there are many stars - including some visible to the naked eye - that are so far away the light we are seeing would seem to have left them much more than 6,000 years ago.
All of that having been said, however, just because we are confident that we see light moving at a constant speed in labs on Earth doesn't necessarily mean that this assumption should never be called into question, nor that we should be completely unskeptical about its validity throughout the universe at large. Completely independent from young-Earth creationism, there are cosmologists who are interested in and investigating the concept of variable speed of light (VSL) cosmology to answer completely unrelated open questions in cosmology. However, there is no real suggestion among scientists at large or those studying VSL that this variability would even conceivably be sufficient to justify a 6,000 year age to the universe, and it seems to not even be widely adopted within the creationist community.
Still, I think that Mr. Ham's point is important to keep in mind for those interested in science. We can very easily embrace a viewpoint that science is a completely objective discipline, insulated from human subjectivity. All scientific investigations do require a set of assumptions, a worldview if you will, in order for them to be extended beyond the immediate observations into a viable scientific hypothesis, which is then tested against the evidence, in the hopes of constructing a broad overall theory to describe the phenomena (and hopefully other phenomena).
The goal of any theory in science is that you get more out of it than you put into it. In terms of an ancient universe, probably nothing in physics is more significant than the discovery of the cosmic microwave background radiation. The presence of this radiation in the universe was predicted by the Russian physicist George Gamow, based upon calculations of the expected energy left over from the Big Bang. The Big Bang itself was not a theory, but rather a prediction that fell out of the theory of relativity and the observational evidence of an expanding universe. When this radiation was actually discovered throughout the universe, it was viewed as significant confirmation of the Big Bang model.
And the opposing steady state model fell by the wayside ... but Fred Hoyle, the brilliant physicist who developed the steady state model, refused to abandon it, and surrounded himself by a group of like-minded individuals who spent years trying to interpret all of the evidence in a way that could justify his model. The profound failure of Hoyle's approach is detailed in the book Brilliant Blunders ... and is a good example of the scientific flaws that can be seen in Ken Ham's approach to science. (See my previous post: Role of Consensus in Science)
Naturalism as a Core Assumption
Mr. Ham also repeatedly brings up naturalism, particularly in a recurring slide that says:
Public school textbooks are using the same word science for observational and historical science. They arbitrarily define science as naturalism and outlaw the supernatural. They present molecules-to-man evolution as fact. They are imposing the religion of naturalism/atheism on generations of students.
Here is, I think, one of the weakest points of Mr. Ham's overall argument, because naturalism in science is not a religion: it is a methodological requirement. When you are conducting science, you simply must assume naturalism. The religious, young-Earth creationist inventor of the fMRI machine could not have done it if he did not assume natural causes in constructing it. If you cannot assume that a natural phenomenon has a natural cause, and that applying the tools of science - which include reason and logic - you can gain insights into those natural causes (and other relationships), then you cannot do science. It's just not possible. If you go into an investigation without the assumption of a natural cause at work, then you are wasting your time, because so far as we know those are the only sorts of causes that science is equipped to discover.
So what Ken Ham is really suggesting above is that public school science textbooks should teach that sometimes science just doesn't work.
Now, naturalism can certainly be more than a methodological requirement. Certainly many people who go into the sciences do so because they believe not just that naturalism is a useful tool, but because they believe that fundamentally naturalism is the way the universe functions. In this sense, it is a metaphysical foundation for many scientists, both atheist and theist.
But one of Ken Ham's arguments is that teaching Creationism will in no way diminish America's leading role in scientific research and innovation. However, it seems like undermining naturalism within science classes - the very place where it plays a central role - cannot help but hurt scientific interest among those who would be most inclined toward embracing it. There would certainly still be scientists, but these would now be scientists who believe that science is the primary way of understanding the universe. As Ken Ham has pointed out in the debate, these scientists can be perfectly valid at doing observational and experimental science, but I can think of no brilliant theoretical physicists who embraced this view.
Even notable theist scientists, such as Sir Isaac Newton and Galileo Galilei, were driven by the belief that the universe functioned according to natural laws, which could be discovered by exploring those natural laws. In fact, the very notion that these natural laws were eternal began as a philosophical and theological stance!
It seems to me therefore that from a practical standpoint, we run into the following problem with the young-Earth creationist position as presented by Ken Ham:
If we allow supernatural explanations for natural events in science classes, how do we define precisely when we move from natural to supernatural explanations?
The failure to answer that question, I think, points to a broader problem ... and, indeed, to the real clash between creationism and evolution.
"Creation Science" Teaches That Science Doesn't Work
Let me step away for a moment from Ken Ham's points to one of the most salient points made by Bill Nye during the debate, which was that science is both the set of facts we have about the natural world and also the process we have for obtaining and interpreting those facts.
Fundamentally, Ken Ham's argument is that science is wrong. And it's not just a little wrong. It's massively wrong. In fact, science just doesn't work as a means of understanding our universe. It might give us some cool gadgets in the present, but there is some point (particularly in the past) where it all breaks down.
- Any investigation in science requires adopting a stance of naturalism: that is, assuming that natural phenomena are caused by natural causes.
- In addition, science investigating the past (which Ham calls "historical science" or "origins science") does require additional assumptions, because there are components of the investigation we cannot directly view.
- One core assumption is that the laws of the universe are "eternal," or at the very least that any time-dependent variability can be discerned from the present state of the universe by scientific inquiry.
So what does it take for Ken Ham's creation science to be true? First, it requires that all three of the above are flawed, at least when it comes to investigating origins.
It means far more than that, though, because the age of the universe is not a minor thing. Indeed, nearly every aspect of our modern scientific understanding of nature points to an ancient universe. Ken Ham rightly points out that scientific investigations into origins require assumptions ... but what he doesn't point out is that for his view to be correct, these assumptions have to be entirely incorrect. And these assumptions don't come from just one area of science, but rather from different disciplines independently. If the Earth and the entire universe are only 6,000 years old, then independent assumptions from geology, astrophysics, cosmology, biology/zoology, atomic physics, and various other disciplines are wrong. It would seem like the whole enterprise of science is, in fact, fundamentally flawed!
Because, you see, these assumptions were not the product of a collaboration. They are not the results of a handful of scientists getting together and contriving a way to reach the result they wanted, but rather the product of the scientific community at large, constantly investigating new hypotheses, challenging them, testing them, debating them, and so on. The result is a robust scientific description of the history of the universe that arises out of this interplay of disciplines.
Where will you find scientists gathered together, creating elaborate arguments in an attempt to justify a pre-conceived conclusion? Well, Fred Hoyle's attempt to support the steady state model would work, but few people are supporting that these days, since there's no evidence. No, today you could go to creationist groups like Answers in Genesis. For an example, I strongly recommend a quick walk-through on this essay trying to work around the speed of light objection to a young universe. It is a good read and a sign that the people formulating these ideas are anything but stupid. It is an intelligent, clear, and honorably candid attempt to construct a viable explanation about how to reconcile the current scientific evidence with a seemingly incompatible desired conclusion.
As Bill Nye said, science is both the body of facts about nature and the method of obtaining and interpreting those facts. It is on this last point that the real scientific fail comes in Creation Science. Interpreting the evidence with a pre-ordained conclusion is not, in any sense of the word, good scientific method ... as Fred Hoyle demonstrated.
So, in the end, the biggest lesson we can learn from Ken Ham is how to not perform science.