Sunday, February 14, 2016

Why care about gravitational ripples?

Once in a while one has to lift the gaze from the alleys and streets and set the eyes higher for a bigger view. What bigger view is there than the one of the entire universe?
Ligo, precision architecture

This is about the celebration of two pieces of architecture worth $505 million that had started in 1992 and had to overcome a bunch of congressional hurdles until they were positioned as a perfect L each 2.5 miles long.

Actually, for scientific reasons and also for nice geopolitical balance, the facility comes as a set of twins working in unison as a single “observatory”: one in southeastern Washington State and the other in rural Livingston, Louisiana, both collaboratively operated between CalTech and MIT. Of course, this is a reference to LIGO, or  the Laser Interferometer Gravitational-Wave Observatory and last week's official announcement of its experimental verification of gravitational waves first seen by Italian researcher Marco Drago on his computer monitor as a less than half second flicker in far away Hanover, Germany on September 14, 2015. After 5 months of intense scrutiny last week's official announcement was a nice post mardi-gras surprise. The measurement had been obtained on the equipment even before the official operation of the upgraded LIGO facility had begun. What was seen on the computer was the footprint of the spectacular collision of two super-suns 1.3 billion years ago which ended in an invisible black hole in a far away galaxy.
what happens inside those long "legs" of the L

The US could use a little science booster after the Higgs Boson had been discovered in Switzerland, even though CERN and LIGO are, of course, international collaborations which both include the US. Still, CERN is a manifestation of Europeans being able to build that collider whereas America's own Texas tunnel had been abandoned after it had been partially dug because it was deemed a too expensive boondoggle. So as a kind of balancing justice the large scale inference detector was not built in Germany, the home of Heinz Billing, inventor of the tool, now 101 years old, but in the US.

LIGO's infinitely small measurement is proof that gravitational waves exist not only in Einstein's imagination. This is a big story for anybody who cares about knowledge and discovery.
Einstein in 1921, six years after describing General Relativity

There are plenty of articles that explain gravity as a weak force and why it is so hard to work it into the standard model of physics. Einstein needed the construct of "space-time" and a fourth dimension to describe gravity in a more complete manner than Newton had been able to do it. That fourth dimension is still pretty absent in the thinking of architects and urban designers, (many students struggle to think beyond two dimensions) but that could change eventually.

The detection of gravitational ripples opens also a new dimension to how humans can observe the universe. No longer limited to light and electromagnetic background radiation, now darkness comes into focus, specifically dark holes and through gravitational disturbances the first 400,000 years of the universe when it was still opaque and light couldn't travel.

The successful measurement is also as symbol for engineering perseverance. For the past 30 years, new gravitational wave detectors were built, but failed to detect extra-galactic signals.  Scientists and engineers returned to the drawing board again and again to refine their instruments. 

But still, why should one care? 

The question of the practical utility of such expensive research has been asked time and again.

One response is, that what sets humans apart from the rest of nature is inquiry beyond the immediate needs of food, mating and defense. One could say that humans are condemned to acquire knowledge ever after eating from "the tree of knowledge" that got them expelled from "paradise" if we understand paradise as a term for of being in perfect sync with nature. Without better knowledge of natural systems including the universe humans will stand no chance to develop sustainable and resilient systems that can exist in harmony with nature.

Another response: Without what was then also exceedingly esoteric research of Newton, Faraday, Maxwell and Einstein one  could not read this article on an electronic device, nor would there be electricity, without it there would be no radio, no telephone, no GPS and not much of what is called civilization today.

It isn't unreasonable to extrapolate this trajectory forward and assume that finding the Higgs or proof of gravitational ripples will become in due time equally useful building blocks in the grand human endeavor of gaining knowledge, a quest which will never be finished. 

Just like electricity, electromagnetism and GPS already do, gravity research may one day help cities become better places. 

Klaus Philipsen, FAIA


Got Gravitational Waves? Science
Gravity waves from black holes verify Einstein’s prediction, Science News