Lord May of the Royal Society

The Royal Society is 345 years old, as of November 30. For the world’s oldest extant scientific society, this year is not as grand or glamorous as a nice round anniversary, like 350 or 400. However, this is the last year of the Royal Society under the Presidency of Lord May of Oxford. Lord May therefore gave not only the anniversary address, but his valedictory address. The title of his speech was “Threats to Tomorrows World”, and can (and should) be “viewed in a webcast”:http://www.royalsoc.ac.uk/page.asp?tip=1&id=3861. In addition, you can “read a press release from the Royal Society about this event, including quotations from the written version of his speech”:http://www.royalsoc.ac.uk/news.asp?id=3944.

The chance for me, a young physicist thousands of miles away, to watch this valedictory address was a moving and remarkable achievement. When I think about all the technological and scientific advances that our species had to make to achieve a high-quality, video reproduction of a speech by Lord May streamed across a tangle of fiber optics to my powerful laptop computer, I am stricken mute by the realization that I stand on the shoulders of enlightened giants. Not mute enough, however, to avoid squeaking out a few words on my reaction to Lord May’s address.

The central themes of May’s address were framed in a modern mystery in the biological theory of evolution. This problem, which involves understanding cooperation, was then used to highlight the three issues central to his talk: climate change, biodiversity, and disease. Beginning with a description of “marmot”:http://dictionary.reference.com/search?r=2&q=marmot behavior, Lord May spoke of the mystery of cooperation. It is in the best interest of a single individual in a marmot society, when threatened, to raise the alarm. While this requires an expenditure of energy above and beyond normal life processes, the cost incurred pales by comparison to the benefit obtained from the response of the collective. However, the problem of cooperation is the cheater. Single individuals will realize that they can reap the benefits without themselves ever contributing to the response, merely by raising the alarm. The evolutionary benefit of the positive feedback mechanism is clear to evolutionists, but the existence of cheating (which serves to destabilize the society and threaten the species) is not well understood.

Lord May then spoke about three major problems facing our species. When discussing climate change and biodiversity, Lord May made several observations about the United States. First, he commented on the very thing which I noted the other day: it is odd that the U.S.’s chief negotiator on climate change, who is charged by this nation to address this problem, expends so much energy trying to demonstrate the non-existence of the problem [TAOMPH197]. For my own tastes, Lord May had the answer: this man is a lawyer, not a scientist. Why, Lord May asked, would the United States place a lawyer and **not** a scientist in this role when the science so clearly tells us to *act now*? To paraphrase Lord May, “If you want to defend the indefensible, you hire a lawyer.” In the wider view of this problem of cooperation in terms of evolution and society, the U.S. is the cheater, raising the alarm but making other nations solve the problem. As Lord May noted, while other nations solve the problem for themselves if all nations do not contribute to the solution equitably, all will suffer.

The second observation he made came at the end of his speech, when he addressed the Royal Society and its role as a product of the Enlightenment. It was the Enlightenment, he said, which freed us from authoritarian dictation of the reality of everyday life (e.g. heavy object fall faster than light ones) and gave us the means to address questions of the natural world with direct and personal experimentation. This freedom, echoed in the U.S.’s founding documents as the rights to pursue life, liberty, and happiness, defines modern science. It is the process, the querying coupled with the experiment coupled with the conclusion, that has allowed us to expend energy beyond our own biological capacities to solve ever more difficult problems, including the ones we created.

What Lord May was concerned by is the fact that here in the U.S., the “canonical exemplar of the Enlightenment”, we see the rising tide of pre-Enlightenment fundamentalism threatening to drown all the progress that science, by its definition, allows us to make in the natural world. This fundamentalism, guised in many ways, intends in its own documentation to set aside science and replace it with a faith-informed science, one that blends belief with science. In short, this fundamentalism threatens to take the West back to a time when authoritarian systems dictated reality, rather than observations of the real world.

Lord May noted, perhaps with irony in his words, that while this very dangerous Christian fundamentalism threatens the very Enlightenment principles that made us so successful, we rail as a nation again Eastern fundamentalism. The whole idealogical concept of a “war on terror” is predicated on the assumption that it is critical to eliminate radical Eastern fundamentalism, to save both the East and the West. But while we fire our ideology over an ocean and several seas to save the Middle East, we also turn the guns of ideology inward and crumble the foundations of our very nation. Certainly, if there was irony intended in Lord May’s words, I appreciated it.

Lord May at one point noted in his speech that the lesson of the Enlightenment, if one had to reduce it to a sound-bite, is that an ugly fact trumps a beautiful theory or a comfortable belief. As he closed, he called on the Society, and all scientists, not to let the world retreat from complexity by embracing the dark simplicities of fundamentalism.

.. [TAOMPH197] http://steve.cooleysekula.net/blog/?p=701

Distant Candles Receding

The universe is expanding. We sit on our tiny blue world in, as Douglas Adams put it, an unfashionable Western Spiral arm of a galaxy. This galaxy drifts lonely and unregarded, pulled along by the expansion of spacetime. As we sit here and wonder, the universe in contemplation of itself, we regard our neighbor galaxies as they speed away from us in silence. Cosmically speaking, these galaxies do not just drift lazily in the tug of spacetime – that tug grows stronger every day, accelerating the expansion of the universe.

There have been several observations now that suggest the universe is not only **not** static (as Einstein believed it must be), and not only expanding, but expanding faster with each moment. It is as if some unseen force, a force whose impetus is derived from a dark energy source that fills the universe, is shoving more and more galaxies beyond our relativistic event horizon, faster and faster. Type Ia supernovae, whose fierce birth from stellar death and subsequent fade are like standardized candles winking across the void, speak to us of the acceleration of the universe at different epochs. Data on *high-redshift supernovae*, those which are most distant from us and thus furthest back in time (we see the light of their birth billions of years after they actually occurred, owing to the finite velocity of light), tell us that in the past the universe expanded more slowly than it does now. The echo of the universe’s birth, the distribution of matter and its density across the universe, speaks from the cosmic microwave background and can only be explained by a universe that was born with some inherent dark energy reserve which, in our current epoch, exerts a negative pressure on the universe.

Today, a new paper (promised by its researchers one week ago) appeared in the arXiv, the online physics paper repository. This paper summarizes the first year of data from the Supernova Legacy Survey (SNLS), slated to run a full five years [ASTROPH0510447]. This group used telescopes, and a “rolling search” technique, to identify 71 high-redshift Type Ia Supernovae. They then studied the Hubble diagram of these supernovae and compared that to models of the universe. For instance, they compared models with a dark energy component and a matter density component, models where the universe is expanding or collapsing, models where the curvature of spacetime is flat, open, or closed, and a model where the big bang did not occur. I reproduce below their Fig. 5.

What does this result tell us? First, let’s discuss the axes. The vertical axis represents the density of the universe as contained in dark energy (a non-matter component). The horizontal axis represents the density of the universe as contained in a matter components. For centuries, the assumption was that matter was the dominant component of the mass of the universe – that is, stars and planets and all other matter-particle-based structures caused all the mass in the universe. Now, let’s look at what the data tells us when interpreted in terms of these two densities (these axes).

First, the contours that look like ellipses stretching from the bottom left to the upper right represent the most likely place on this plane for our universe to lie, given the data. The outermost contour is the 99.7% probability contour, which means that the probability that the same experiment repeated over and over and over with unique data sets derived in the same manner would yield results outside the contour is only 0.3%. Statistically speaking, that means that our universe is most consistent with the data when it lies inside that contour. One thing becomes very obvious upon inspection: the big bang mus have occurred. The region that would be populated by universes without a big bang lies in the upper left-most corner, and is very far from the edge of the 99.7% contour. What I find remarkable is just how well this plot represents real science. The big bang theory makes predictions: the universe would have dark energy densities above 1 (and above our contours) if it had never occurred. Here we see this prediction born out by the data. Yet again, the big bang is verified.

These contours also lie well within a region where the universe would have to be expanding more rapidly, rather than slowing (or static). The region of a decelerating universe lies in the lower right corner of the plot, the region where the matter component of the universe must be closer to 1 and thus exerting maximal gravitational self-attraction.

There is more to see in this figure. To see it, we have to consider the impact of an independent data set from the baryon acoustic oscillations (BAO) as measured in the Sloan Digital Sky Survey (SDSS). The contours derived from those data select a region that goes from the upper left to the bottom middle of the figure. Since the BAO data is independent of the SNLS data, and both can be interpreted in this framework, we can combine them (see where their contours overlap) to further constrain our understanding of the universe. The overlaps contours are the small ellipses. From these contours, we see that the data favor a flat universe (one where there is no curvature to spacetime).

Remarkable. Seventy one distant supernovae speak to us across the vast cosmic silence, winking for only an instant when compared to the life of this ancient universe. They tell us of the stretching of spacetime that has occurred since their light left them, billions of years ago, when the galaxies in this universe were 98% closer than they are now. We read from their light the alarming fact that this universe is not only dominated by a source of energy outside of matter, but that this energy is exerting a negative pressure that is accelerating spacetime’s expansion. We sit on the edge of this void at a remarkable moment in the universe’s history, and we ponder.

.. [ASTROPH0510447] “http://arxiv.org/abs/astro-ph/0510447”:http://arxiv.org/abs/astro-ph/0510447

Science and Patterns

Science is a method, one well suited to finding the connections between seeming disparate phenomena. Electricity flow along a wire, a magnetic field flows outward from it, and yet these two phenomena are two sides of a single interaction. Insects foraging food on a jungle carpet, fish foraging food on the sea floor, and yet evolution gives us a predictive framework that points us back to a common ancestor, billions of years old. Science can often take no single phenomenon as a critical piece of evidence, but placed together the pattern emerges. The nodes of a spiderweb tell us nothing of its function, the silk teaches us little about its function. Only by tracing the silk. following the nodes, do we see the web emerge.

Today, when I read the “gross mischaracterization of what science tells us about extreme weather and global climate change”:http://news.yahoo.com/s/ap/20051130/ap_on_re_ca/canada_climate_change;_ylt=AvkGG_5icqKJJ9NMm7EBGVis0NUE;_ylu=X3oDMTA3b3JuZGZhBHNlYwM3MjE-, I was therefore *appalled*. This abuse of science’s conclusions came not from a Turkish reporter, not from a Discovery Institute fellow, and not from a schoolboard member in Kansas. It came from the top US environmental negotiator for environmental issues. Let’s consider the statement: that scientists can’t point to a single phenomenon and definitively pronounce it the sneeze or cough of global warming. By that reasoning, he seems to suggest science can’t conclude anything about the verity for global climate change, and swift action on the part of governments is thus not called for.

While the strength of a single hurricane is not acutely sensitive to climate change, the aggregate of all storms will on average be up to 10% stronger, according to several climate models. While the melting of a single ice shelf in Antarctica can’t be blamed on climate change, the fact that polar ice and glaciers across all continents are receding points a finger. While the CO2 emissions from a single industry cannot be correlated with global temperature, the average of all emissions across a century is strongly correlated. While this year is no more choked by CO2 than a decade ago, its contained CO2 levels unmatched for thousands of year.

Science has revealed a persuasive pattern: greenhouse gas levels rising, carbon sinks depleted, temperatures rising, weather changing. No single phenomenon is necessarily worrying, but taken together the pattern is alarming. To deny the pattern in favor of the pieces is reckless on the part of our negotiator, and at minimum points to a gross misunderstanding of science.

More info: the negotiator is Harlan Watson; the quote was,

“There’s a difference between climate and extreme weather,” Watson said. “Our scientists continually tell us we cannot blame any single extreme event, attribute that to climate change.”

Put ‘Em Up Against The Wall!

I read somewhere recently (or heard somewhere recently?) that most scientists don’t have the scientific method posted anywhere on the walls of their office or lab. I was struck by that fact, until I stopped and said, “Hey, stupid – you don’t have it on your wall, either!”. This morning, I remedied that egregious oversight: I printed off the viewgraph my father made for his chemistry class and posted it on my wall (c.f. [TAOMPH149]). There are two things I like about the way his slide turned out: first, the accuracy of the depiction and second, the personalized way the flow-arrows are frenetically drawn connecting the core tenets of the method.

Christmas is coming fast. In between “seeing the Nutcracker”:http://www.sfballet.org/performances/nutcracker/index.aspx and crossing all those little gifts off the list for family and friends, I’ve gotta get some science done. Mostly, I am worried about the logistics of the several projects I am working on. Second, I actually have to dig some physics out of these projects.

.. [TAOMPH149] http://steve.cooleysekula.net/blog/?p=749