Quantum Diaries

I’ve been away from blogging for quite some time – mainly to finish a book I was working on.   The book is unrelated to particle physics, but follows a course I teach at Harvard, called Primitive Navigation.   We explore navigational techniques used by cultures like the Polynesians and Norse, in addition to looking at environmental topics like the origins of ocean currents and global weather systems.   While doing research for the book and the course, I found that humans have always been exceedingly clever in making sense of their environments and harnessing this knowledge to journey long distances.   I found that the ability of humans to develop sophisticated constructs to bring order to their environment is not limited to the lineage of Western scientific thought but is a more universal trait.

We often think of the roots of science starting with the ancient Greeks, or even further back to the Babylonians.   The canonical history is a marriage of mathematics and logic coupled with empirical observation.  The story stretches through the Arab translations of works like Euclid’s Elements during the Dark and Middle Ages, through the emergence of the scientific revolution, and culminating in the dizzying heights of modern works like quantum field theory.   This is not to say that there weren’t hiccups.   Although most scientists would dismiss astrology as quackery, astronomy and astrology were once deeply intertwined from their Western birth in Babylon through the time of Kepler.

I invite you to take a big step back and ponder the following conjecture – that Homo sapiens has always been intrinsically disposed toward scientific thinking.   This is perhaps not ‘science’ in the way we view Western science, but it still has the existence of conceptual framework on which to hang and connect observations.

In the process of doing research for the book, I interacted with a number of anthropologists who are studying the navigational schemes of Pacific Islanders.   Their work demonstrates the existence of an exceedingly sophisticated ‘toolkit’ of navigational schema that allowed them to travel huge distances across the ocean to find small target islands successfully.   Three anthropologists in particular have uncovered some amazing findings:  Cathy Pyrek, Rick Feinberg, and Joe Genz.

Most archaeological evidence points to the emergence of long-distance voyaging by a group called the Lapita people, circa 1600 BC from the Bismarck Archipelago, near New Guinea.   They built craft capable of sailing into the wind, making jumps of hundreds of miles eastward to locations like Fiji, Tonga, Tahiti and the Marquesas.   Even more astonishing was the rapid explosion of voyages of thousands of miles around AD 1000 to Hawaii and the north island of New Zealand.

In order to sail against the wind, one needs to create a sail capable of lift, like a wing and use it in combination with a hull that ‘grabs’ the water as it slices through.    The Lapita figured how to harness the complex fluid dynamics involved in lift and used it to their advantage.  In the 18^th century, Captain James Cook marveled at sophisticated design of the Polynesian voyaging canoes that allowed them to travel at speeds far in excess of Western European vessels.  It wasn’t until 1904 that physicist Ludwig Prandtl laid out the theoretical basis for lift in wings, and wasn’t until the 1970’s that this theory was applied to sails.

The clever design of voyaging canoes was only part of the innovations the Pacific Islanders.   In order to sail across vast stretches of ocean, they needed viable navigational schema.    We don’t have written records from the height of the voyaging period for Polynesians (circa AD 1000), but we do have interviews with modern day practitioners of indigenous navigational techniques that hint at the ways their ancestors crossed large stretches of ocean accurately.

Anthropologists Rick Feinberg and Cathy Pyrek from Kent State have shown how indigenous navigators in eastern Solomon Islands use a ‘navigational tool-kit’, that consists of multiple signs.   Stars that are rising or setting close to the horizon form a natural star-compass.  Their rising and setting positions allow navigators to find the ‘azimuth’ or compass heading toward a destination island.   This requires the navigator to memorize a large number of stars and become familiar with their paths across the sky at different times of the year.

While a star compass may be useful, what does a navigator do during the day or in overcast weather?   Another helpful construct is a wind-compass.  Winds blowing from different directions have different characteristics.    In the eastern Solomons, the trade winds blow from the southeast, and are marked by characteristic ‘trade wind cumulus’ clouds that only grow to heights of roughly 15,000 feet and are then truncated.   These winds mark the direction ‘tonga’, or the southeast, which corresponds to the direction of the island cluster of Tonga.   Winds from the north arrive during the winter months and are associated with variable, stormy weather.

Steady winds and storm systems can also create ocean swells that act as reliable direction indicators.  Often, multiple swells can arise – for example, the Southern Ocean produces a long swell from the south, while trade winds can create shorter wavelength swells from the east.   Even if the wind shifts, the swells retain some ‘memory’ of the winds that created them allowing the navigator to maintain a steady heading.

The above tools are useful in maintaining direction under different conditions, but there’s an inherent uncertainty in the position of a vessel, and this uncertainty grows with time.   A navigator completing a 200-mile journey may only be able to establish a position to within 20 or 30 miles.   Another trick then comes into play:  birds.   Certain birds, like pelicans and frigate birds will fly some distance out to sea to feed, and then will return to their home islands in the evening.   A sailor only has to get to within 30 miles of a target island and then observe land-based birds.   The sail is dropped and when the birds fly home in the evening, a course is set.

The navigational toolkit allows for a kind of successive approximation, where the stars, wind, and swells form a rough guide, and the presence and behavior of birds provides the final precision.

A somewhat related but unique tradition is that of wave-piloting in the Marshall Islands.  Most of us are familiar with refraction and reflection of waves, whether they’re light or sound waves.   Waves on the oceans’ surface are similar, but have some notable differences.   First waves in deep-water have a speed that is proportional to the square root of the wavelength.   Second, waves in shallow water have a speed that’s proportional to the square root of the depth.   This latter relation causes waves to refract in shallow water.   When waves get into very shallow water, they’ll often break, losing much, if not all of their energy.   On the other hand, waves impinging on a steep cliff that extends underwater will reflect with very little energy lost.   Depending on the bathymetry surrounding an island, one can get very different wave patterns produced by the interaction of an incident swell with the island.

Joe Genz from the University of Hawaii studied the tradition of Marshall Island wave piloting for his doctoral thesis.   Navigators in the Marshalls have their own language for describing characteristic wave patterns around islands. Nit in kōt is the name given to a crossing pattern of waves on the lee side of an island.   If a uniform swell impinges in the eastern shore of an island, the waves passing the north shore will be refracted inside the swell-shadow toward the south and the waves passing the south shore will be refracted into the swell-shadow toward the north.   The resulting pattern of crossing waves creates a disturbed region that’s easy to identify at distances beyond which the islands are visible.

In principle, reflected ways should also give clues to the presence of an island.  Joe made the acquaintance of one Captain Korent Joel, a native Marshall Islander who was trying to revive the tradition of wave piloting.   Joe persuaded Captain Korent to demonstrate his wave piloting technique to a group of oceanographers who deployed a set of sensitive wave buoys.  As Captain Korent left the atoll of Arno, he first pointed out the incoming swell from the east, and then the reflected swell off of Arno.

There was only one problem.   No one on the boat with Captain Korent could notice the reflections, although the dominant eastern swell was clearly visible.   Even the sensitive wave buoys couldn’t detect the presence of the reflected swell.    What was going on?    Joe wondered whether Captain Korent just thought he should be seeing a reflected swell and was making this up.

In order to put Captain Korent to a sterner test, Joe waited until he (Captain Korent) was taking a nap on in the cabin.   Joe instructed the crew to motor some 30 miles to the southwest of Arno to get to a new location.   When Captain Korent woke up, Joe told him that he had taken the boat to an undisclosed location and asked him if he could identify the direction to Arno, and the kind of wave patterns he was seeing.   Captain Korent was quite certain the Arno was to the northwest, and he was also quite correct!   So, he was reading the waves properly after all!

I met Joe in person at a conference of the Association for Social Anthropology in Oceania (ASAO) in Portland Oregon in February 2012.    Joe had some videos on his laptop of Captain Korent and shared them with me.   I downloaded them to my computer.   That evening, I watched the video where Captain Korent was pointing out the reflected swell to Joe on the boat.   This was the reflected swell that Joe couldn’t see, and the oceanographer’s buoys couldn’t detect.   Joe told me what Captain Korent was saying in Marshallese about the waves.   I do some sea kayaking, and I’m often close to the water, and am a bit of an amateur wave-watcher myself.

In my first viewing of the video, I could definitely see the incoming dominant swell from the east.   But, by the third or fourth viewing, I could see a weaker reflected swell moving at slight angle against the larger incoming swell.   When I compared my observations to what Captain Korent was saying in Marshallese, they agreed completely!  By the tenth viewing, I became 100% convinced that Captain Korent was pointing out the reflected swell correctly.

The next day, I called Joe over, along with Cathy Pyrek, who was also attending the ASAO conference.   I pulled up the video on my laptop and showed what I saw as the reflected swell.   Joe said, “Oh yeah, now I see it”.    I turned to Cathy and asked if she really saw it, or I was just convincing them of it, but she said,“It’s definitely there, it’s strange that everyone missed it.”

We still have much to learn about how the human mind operates, but it struck me that Captain Korent’s talents show how we’re capable of picking up very weak signals in the presence of noise.   Evidently there is more information on the surface of the ocean than the oceanographer’s buoys were capable of recording.   This is perhaps not surprising, but it’s evidence that there are different frameworks of knowledge out there that are effective and are based on empiricism.   It may not be Western, but it is a kind of science.

For further reading:

Joeseph Genz, et al., “Wave Navigation in the Marshall Islands,” Oceanography, 22, June 2009, 234-245.

Joseph Genz, “Marshallese Navigation and Voyaging: Re-learning and Reviving Indigenous Knowledge of the Ocean,” (PhD diss., University of Hawaii, 2008)

John Huth, The Lost Art of Finding Our Way, (Belknap Press, Cambridge MA, 2013).

Twitter:  @JohnHuth1

Now that we might (maybe, possibly, could be, it could go away, let’s be careful about what we say here lest we put a jinx on it…) be seeing hints of a Higgs, it’s time of some cautionary tales that a ‘discovery’ is not the end of the story, it’s only the beginning.

When I was a young graduate student, Martinus Veltman gave a talk at a summer school. He had yet to share the Nobel Prize in physics with Gerard t’Hooft for work on the Standard Model. This was 1980. Veltman said, “Right now, theorists are in the driver’s seat. In fact, for the next 30 years, with the exception of the details of the masses of some particles, we know what’s going to happen. But in 30 years, we absolutely are going to need experimental guidance to make any progress in particle physics whatsoever.”

In point of fact, I don’t think anyone recorded Veltman’s words for posterity, but it made a deep impression on me in a number of ways. First and foremost to a rookie experimentalist was the realization that I had to toil in the vineyards for thirty years until something truly of note would arrive. The second thought was “What on earth is he talking about?” We were handed the Higgs boson as an article of faith.

In the current publicity about the Higgs boson, I often worry that we simplify the goals of what we’re doing to the point of trivializing it. Veltman was right: What we call the “Higgs boson” or the “God particle” is really a surrogate for a strange mechanism that bestows mass on all particles through an interaction. We have the most precise theory of anything and, yet, this absolutely crucial piece is missing. We’ve gotten to that point, 30 years later, at which we’ve found almost all of the particles theorists predicted as part of the Standard Model and are now heading into uncharted territory in higher energy ranges.

What we don’t often talk about are the odd properties that this mysterious particle is thought to have. Often times, theorists, like Veltman, feel that the current model is horribly inelegant and must therefore be completely wrong and only a pale approximation of what nature really does to bestow mass, the most elemental of properties a particle can possess.

What makes it so inelegant? In the first place, if it is as described in our simplest model, it would be the only elementary particle we know of that doesn’t possess an intrinsic property of ‘spin’, which seems to be key in the workings of our theory of fundamental forces. For more on the inherently quantum mechanical property of particles known as spin, see this post by Flip Tanedo.

Beyond its spin 0, the Higgs has a very odd property: It gives energy to the vacuum of space. We don’t really know what this means and often just ignore it. Yet, a kind of vacuum energy has been invoked to describe cosmology on very different energy scales from the energies we’re exploring at the LHC. Astrophysicists often talk about something called the “flatness problem”.

If you took a pot of boiling water just off the stove, and dumped ice into it, eventually you would see the ice and the hot water come to some equilibrium temperature. But, in order for this to happen, the ice and hot water have to physically come in contact with each other. When we look around the universe, the temperature of everything is the same to a remarkable degree, as if it was all sitting in the same pot and came to the same temperature. That would all be well and good, but one patch of the universe cannot possibly have been in contact with another part, because they’re separated by such a large distance that light itself cannot connect the two. How could the entire universe be at the same temperature?

The answer is largely thought to lie in a period called ‘inflation’. Initially the very early universe was so dense and compact that temperatures from one part could communicate to another part: everything was sitting in the same ‘pot’. Then, a mysterious vacuum energy appeared that pushed parts of the universe out of contact, but preserved the uniformity of temperature. This happened within a very early phase of the universe when temperatures and energy densities were far hotter than the conditions we’re producing at the LHC. This vacuum energy is about a trillion times larger than what we associate with the Higgs.

Astrophysicists have also invoked a vacuum energy at another, much weaker scale. You may have heard of ‘dark energy’. Our best guess is that, like the vacuum energy of the early universe, this mysterious force that seems to be pushing the universe apart also seems to be a kind of vacuum energy. Yet, in this case the energy of the vacuum is exceedingly weaker than the energies we’re exploring at the LHC. So, there’s a vacuum energy invoked to explain both the very early universe and the very late universe. At the same time, there’s a vacuum energy associated with the Higgs, but it just sits there like an orphan, of no consequence.

To deal with some of these strange properties, theorists have come up with other ideas for how the Higgs might manifest itself:

1.) Supersymmetric Higgs – The energy scale where the three main forces other than gravity, the strong, weak and electromagnetic- join together is close to the scale associated with the cosmic inflation. This is often called the ‘Grand Unification scale.’ The fact that we see two of the fundamental forces – weak and electromagnetic – joining together at the LHC energies presents a conundrum. It is very difficult to reconcile the Grand Unification scale with the LHC scale in a natural way without having some other kinds of matter arise. The constants of the theory would have to line up just perfectly, fine-tuned to a level of precision that is equivalent to balancing a pencil on its point. With Supersymmetry, a number of Higgs-like particles arise.

2.) Composite Higgs – Rather than deal with an inelegant particle with no spin, theorists have speculated that it’s actually made of multiple objects, possible pair of top quarks, tightly bound together. The opposite spins of the objects bound together in a composite Higgs would cancel out to give it zero spin.

3.) No Higgs –According to some models, the Higgs is not a particle at all, but the result of interactions that create mass. These models are sometimes called ‘technicolor’. Although they aren’t particularly favored by theorists because they’re difficult to calculate, we cannot rule them out.

Experimentalists are checking the data for all of these possibilities.

But, what if something like our vanilla-Higgs shows up with a high degree of certainty? Are we done? Hardly! Given all the possibilities and the somewhat inelegant nature of the vanilla-Higgs model, the work has just begun. We have to ask questions like: Is there only one? What is its spin? How does it interact with all the other particles? Are there any variations in its interactions from what we expect, and if so, how does that relate to other measurements we do. These are the tough questions, the one Veltman was alluding to and my betting odds are that we’ll find deviations from our vanilla-Higgs, but it won’t be easy. It may take a decade or more of data taking at the highest beam intensities and energies before we begin to understand what’s really going on.

Science may begin with blinders and theories may run aground, but eventually we do manage to figure out what’s going on.

Here’s a cautionary tale from the 19th century. It illustrates how people can be steered in the direction of one theory, but ultimately can end up with a far more powerful idea.

A German geographer named August Petermann championed a theory of a warm Polar sea. Some expeditions to the high Arctic reported seeing vast stretches of ice-free water extending off toward the horizon. An oceanographer named Silas Bent speculated the that warmth of the Gulf Stream waters flowing north, combined with the waters of a similar ocean current, called the Kurosiwa (black current) flowing off of the coast of Japan would be sufficient to warm the Polar Ocean to the point that an expedition, if it could make it through some part of the ice pack, could sail directly to the Pole. Petermann was one of the main champions of the idea.

James Gordon Bennett Jr. was the publisher of the New York Herald and tried to boost publication by underwriting adventurous expeditions. He financed Henry Morton’s Stanley’s search for David Livingston, garnering a boost in the circulation of the Herald. Hearing of Petermann’s theory of the warm polar sea, Bennett set about to finance an expedition and purchased a British gunboat, the HMS Pandora, and refitted it. He enlisted the US Navy to find a crew. Rechristened the USS Jeanette, it was captained by Lieutenant Commander George DeLong. Hoping to repeat the publicity of the famous Stanley-Livingston meeting, Bennett sent the Jeanette north through the Bering Strait in hopes of reaching the famed open Polar Sea. The Jeanette left San Francisco in July 1879, and was last heard from in late August of that year.

After crossing the Bering Strait, the Jeanette was soon frozen fast in the icepack. Trapped there for nearly two years, it slowly drifted northwest from the coast of Siberia and was ultimately crushed by the icepack. DeLong ordered his crew to abandon ship and began a trek over the frozen icepack, hauling three lifeboats in hopes of eventually reaching settlements along the delta of the Lena River in Siberia. DeLong didn’t make it out alive, perishing in the maze of channels. Some survivors did make it to settlements and eventually made it back home.

Three years later, the wreckage of the Jeanette washed up on the coast of Greenland, some three thousand miles away. This prompted many to wonder how the wreckage could travel so far across the frozen icecap. Theories about ocean current proliferated. One adventurer, Fridtjof Nansen, constructed a polar exploration vessel, the Fram. Fram had a rounded hull that allowed it to be frozen into the icepack without being crushed. Nansen and crew sailed to roughly the point where the Jeanette had been frozen in and commenced a drift across the Polar Sea. At this point, the theory of the Open Polar Sea was completely abandoned in the face of the overwhelming data to the contrary.

Although Nansen never reached the North Pole, during the Fram’s expedition, the remaining crew made detailed observations of wind patterns, drift, the ocean depths and temperatures. On its return to Norway, the Fram had a wealth of data that took years to sift through. Vagn Ekman was a student in physics at the University of Uppsala, Sweden. He was studying fluid dynamics and heard of the data from the Fram. After exploring the mathematics of the interactions of air and water flow on the surface of the rotating earth, he developed the modern theory of surface ocean currents, which bears his name: Ekman transport.

Ekman’s work remains one of the fundamental underpinnings of oceanography.

What I’m trying to point out is this: We are on a voyage of discovery. As Veltman said, experimentalists are really now the ones in the drivers seat. The vanilla-Higgs is an easy target to fire at, as there are quite specific predictions for how it will be manifested, but there are good reasons to be suspicious that the Higgs is precisely as it is described in the simplest version of the Standard Model. Like the long, meandering progression from the theory of the Open Polar Sea to the modern theory of Ocean Currents, I suspect that we’ll have many changes and false leads. As it stands now, with the performance of the LHC, we are just beginning to penetrate the icepack, and we don’t really know what to expect.

A rendering of the long retreat to the Lena River Delta by the DeLong Expedition