Tag: Spacetime

Planetary Scale

[Image: “CHRONOS: The Space-Time Planetarium,” proposed by Drew Heller, Isabella Marcotulli, and Ibrahim Salman, via Eleven Magazine].

With news of “the largest planetarium in the Western Hemisphere and the fourth largest in the world” opening in New Jersey, I’m reminded of a design competition I meant to post about earlier this year.

A few months ago, Eleven Magazine hosted a quick competition to rethink the planetarium. It’s a great design brief: Eleven’s editors asked “if architecture itself could become—once again—a tool for experiencing and understanding space. How can architecture engage with and enhance today’s renewed age of space exploration and discovery? What does the next generation of planetariums look like?”

You can click around on the various entries here, but a few seemed worth mentioning.

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

The “Microsphere” proposal, for example, entails “a network of little planetariums scattered all over the world.” As the title suggests, each planetarium would be a small, single-occupancy sphere acting as a meditative space for viewing, studying, or thinking about the cosmos.

It’s an idea that only suffers from the unnecessary stipulation that these should be built directly next to existing, often very ancient sites of star observation, including Stonehenge. Not only does Stonehenge not need this sort of thing parked next to it, but installing these out in the suburbs, on city streets, on the roofs of low-income housing units, or even hidden in thickets in state parks would seem to be a much more interesting way for these structures to bring astronomy to the masses.

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

Another project is interesting for its attempt to reconceive what “space” really is and how a planetarium is meant to represent or engage with it.

[Image: “CHRONOS: The Space-Time Planetarium,” proposed by Drew Heller, Isabella Marcotulli, and Ibrahim Salman, via Eleven Magazine].

Acting as a “space-time planetarium,” a project called CHRONOS would allow visitors to “perceive astronomical scenes at different rates… through a labyrinth of six architectural techniques that invite the user to abandon earthly notions of space and time.”

The building thus requires a “space-time diagram.”

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

Whether or not the resulting building would actually resemble what the designers have proposed here, it sounds awesome. “The planetarium grounds users through abstract learning as they navigate the entanglement while warping their perception of space-time,” they write. “While traveling through a series of architectural space-time scenarios, users are enlightened with astronomical scenes that transcend human perception.”

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

As you’d expect, not every entry is particularly interesting and there are some real doozies in there, but it’s worth checking out. While you’re there, though, check out the other competitions—some still ongoing—that Eleven has hosted.

Archiving “Geomagnetic Spikes” in Everyday Objects

[Image: One of the pots; photo by Oded Lipschits, courtesy NPR].

Ancient clay pottery in the Middle East has inadvertently recorded the Earth’s magnetic field, including evidence of an “astonishing geomagnetic spike.”

“All those years ago,” NPR reported earlier this week, “as potters continued to throw clay, the molten iron that was rotating deep below them tugged at tiny bits of magnetic minerals embedded in the potters’ clay. As the jars were heated in the kiln and then subsequently cooled, those minerals swiveled and froze into place like tiny compasses, responding to the direction and strength of the Earth’s magnetic field at that very moment.”

Archaeologist Erez Ben-Yosef, one of the researchers on the project, has compared the process to a terrestrial “tape recorder,” and a particularly sensitive one at that: the resulting jars “provide an unprecedented look at the planet’s magnetic field over those six centuries, one that’s much harder to get from rocks.”

These accidental indices also indicate that the Earth’s magnetic field at the time was much stronger than expected; ominously, this “astonishing geomagnetic spike,” as mentioned above, could happen again. Indeed, the jars have “given scientists a glimpse of how intense the magnetic field can get—and the news isn’t good for a world that depends on electrical grids and high-tech devices,” Annalee Newitz writes for Ars Technica.

“The researchers note that this geomagnetic spike is similar to another that occurred in the 10th century BCE,” Newitz adds. “Data from the 10th century spike and this 8th century one indicate that such events were probably localized, not global. That said, they write that ‘the exact geographic expanse of this phenomenon has yet to be investigated, and the fact that these are very short-lived features that can be easily missed suggests that there is much more to discover.’”

This vision—of highly localized, mysterious geomagnetic storms frying electronics from below—is not only a great plot device for some burgeoning scifi novelist, it could also almost undoubtedly be weaponized: subterranean geomagnetic warfare against an entire region of the planet, short-circuiting every electrical device in sight.

[Image: One of the pots; photo by Oded Lipschits, courtesy NPR].

Of course, it’s also worth noting that this would still be happening: that is, today’s ceramics should still be “recording” the Earth’s magnetic field, even without any corresponding spike in that field’s strength. An invisible terrestrial forcefield is thus still inscribing itself inside objects in your kitchen cabinet or standing on your breakfast table. Everyday knick-knacks in retail stores around the world are still archives of planetary magnetism.

This also makes me wonder what other types of artifacts—clay figurines from nomadic Arctic tribes, mud bricks from central Africa—might also house geomagnetic records yet to be analyzed by modern technology. So what else might be discovered someday?

I’m reminded of the possibility that space weather—or “fossils of spacetime”—might be frozen into the built environment in the form of GPS glitches: hidden inside minute structural errors in large building projects, such as freeways, dams, and bridges, there might be evidence that our solar system is passing through “cosmic kinks” of dark matter.

In any case, read the original paper in PNAS; see also The New Yorker.

The London Time Ball

timeball[Image: The London “time ball” at Greenwich, courtesy Royal Museums Greenwich].

Thanks to the effects of jet lag getting worse as I get older, I was basically awake for five days in London last week—but, on the bright side, it meant I got to read a ton of books.

Amongst them was an interesting new look at the history of weather science and atmospheric forecasting—sky futures!—by Peter Moore called The Weather Experiment. There were at least two things in it worth commenting on, one of which I’ll save for the next post.

This will doubtless already be common knowledge for many people, of course, but I was thrilled to learn about something called the London “time ball.” Installed at the Greenwich Royal Observatory in 1833 by John Pond, England’s Royal Astronomer, the time ball was a kind of secular church bell, an acoustic spacetime signal for ships.

It was “a large metal ball,” Moore writes, “attached to a pole at the Royal Observatory. At 1 p.m. each day it dropped to earth with an echoing thud so that ships in the Thames could calibrate their chronometers.” As such, it soon “became a familiar part of the Greenwich soundscape,” an Enlightenment variation on the Bow Bells. Born within sound of the time signal…

timeball1[Image: Historic shot of the time ball, via the South London Branch of the British Horological Institute].

There are many things I love about this, but one is the sheer fact that time was synchronized by something as unapologetically blunt as a sound reverberating over the waters. It would have passed through all manner of atmospheric conditions—through fog and smoke, through rain and wind—as well as through a labyrinth of physical obstructions, amidst overlapping ships and buildings, as if shattering the present moment into an echo chamber.

Calculating against these distortions would have presented a fascinating sort of acoustic relativity, as captains and their crew members would have needed to determine exactly how much time had been lost between the percussive thudding of the signal and their inevitably delayed hearing of it.

In fact, this suggests an interesting future design project: time-signal reflection landscapes for the Thames, or time-reflection surfaces and other acoustic follies for maritime London, helping mitigate against adverse atmospheric effects on antique devices of synchronization.

In any case, the other thing I love here is the abstract idea that, at this zero point for geography—that is, the prime meridian of the modern world—a perfect Platonic solid would knock out a moment of synchrony, and that Moore’s “echoing thud” at this precise dividing line between East and West would thus be encoded into the navigational plans of captains sailing out around the curvature of the earth, their expeditions grounded in time by this mark of sonic punctuation.

Islands at the Speed of Light

A recent paper published in the Physical Review has some astonishing suggestions for the geographic future of financial markets. Its authors, Alexander Wissner-Gross and Cameron Freer, discuss the spatial implications of speed-of-light trading.

Trades now occur so rapidly, they explain, and in such fantastic quantity, that the speed of light itself presents limits to the efficiency of global computerized trading networks.

These limits are described as “light propagation delays.”

[Image: Global map of “optimal intermediate locations between trading centers,” based on the earth’s geometry and the speed of light, by Alexander Wissner-Gross and Cameron Freer].

It is thus in traders’ direct financial interest, they suggest, to install themselves at specific points on the Earth’s surface—a kind of light-speed financial acupuncture—to take advantage both of the planet’s geometry and of the networks along which trades are ordered and filled. They conclude that “the construction of relativistic statistical arbitrage trading nodes across the Earth’s surface” is thus economically justified, if not required.

Amazingly, their analysis—seen in the map, above—suggests that many of these financially strategic points are actually out in the middle of nowhere: hundreds of miles offshore in the Indian Ocean, for instance, on the shores of Antarctica, and scattered throughout the South Pacific (though, of course, most of Europe, Japan, and the U.S. Bos-Wash corridor also make the cut).

These nodes exist in what the authors refer to as “the past light cones” of distant trading centers—thus the paper’s multiple references to relativity. Astonishingly, this thus seems to elide financial trading networks with the laws of physics, implying the eventual emergence of what we might call quantum financial products. Quantum derivatives! (This also seems to push us ever closer to the artificially intelligent financial instruments described in Charles Stross’s novel Accelerando). Erwin Schrödinger meets the Dow.

It’s financial science fiction: when the dollar value of a given product depends on its position in a planet’s light-cone.

[Image: Diagrammatic explanation of a “light cone,” courtesy of Wikipedia].

These points scattered along the earth’s surface are described as “optimal intermediate locations between trading centers,” each site “maximiz[ing] profit potential in a locally auditable manner.”

Wissner-Gross and Freer then suggest that trading centers themselves could be moved to these nodal points: “we show that if such intermediate coordination nodes are themselves promoted to trading centers that can utilize local information, a novel econophysical effect arises wherein the propagation of security pricing information through a chain of such nodes is effectively slowed or stopped.” An econophysical effect.

In the end, then, they more or less explicitly argue for the economic viability of building artificial islands and inhabitable seasteads—i.e. the “construction of relativistic statistical arbitrage trading nodes”—out in the middle of the ocean somewhere as a way to profit from speed-of-light trades. Imagine, for a moment, the New York Stock Exchange moving out into the mid-Atlantic, somewhere near the Azores, onto a series of New Babylon-like platforms, run not by human traders but by Watson-esque artificially intelligent supercomputers housed in waterproof tombs, all calculating money at the speed of light.

[Image: An otherwise unrelated image from NOAA featuring a geodetic satellite triangulation network].

“In summary,” the authors write, “we have demonstrated that light propagation delays present new opportunities for statistical arbitrage at the planetary scale, and have calculated a representative map of locations from which to coordinate such relativistic statistical arbitrage among the world’s major securities exchanges. We furthermore have shown that for chains of trading centers along geodesics, the propagation of tradable information is effectively slowed or stopped by such arbitrage.”

Historically, technologies for transportation and communication have resulted in the consolidation of financial markets. For example, in the nineteenth century, more than 200 stock exchanges were formed in the United States, but most were eliminated as the telegraph spread. The growth of electronic markets has led to further consolidation in recent years. Although there are advantages to centralization for many types of transactions, we have described a type of arbitrage that is just beginning to become relevant, and for which the trend is, surprisingly, in the direction of decentralization. In fact, our calculations suggest that this type of arbitrage may already be technologically feasible for the most distant pairs of exchanges, and may soon be feasible at the fastest relevant time scales for closer pairs.

Our results are both scientifically relevant because they identify an econo-physical mechanism by which the propagation of tradable information can be slowed or stopped, and technologically significant, because they motivate the construction of relativistic statistical arbitrage trading nodes across the Earth’s surface.

For more, read the original paper: PDF.

(Thanks to Nicola Twilley for the tip!)