The Awesome Wonder of Gravitational Waves

I don’t usually write about science, because I don’t know much about it. I haven’t taken a science class since Physics in my senior year of high school. What impressed me most when I learned about waves in that class was that wave theory explained music—why some chords sound wonderful and others discordant. I could tune my guitar much better after taking Physics, because I understood what I was doing.

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Hanford LIGO installation, Northern leg

My excuse for writing this post about the recent announcement that evidence of gravitational waves has been found is that one part of the Laser Interferometer Gravitational-wave Observatory (LIGO) system that investigated these waves is located in Hanford, Washington, near where I grew up.

LIGO is composed of two mammoth laser installations—one in Hanford and the other in Livingston, Louisiana. Each of the LIGO sites is L-shaped, with two 2.5 mile-long arms containing lasers. The Hanford LIGO installation is located on the Hanford nuclear reservation, between the Columbia River and Rattlesnake Mountain. It’s an hour’s drive from Richland on a remote desert plateau covered primarily by sagebrush.

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Hanford LIGO installation, Western leg (with Rattlesnake Mountain in the background)

The theory behind the design of the LIGO installations is that a gravitational wave shortens the path of the laser in one arm and stretches it in the other. Albert Einstein postulated the existence of these waves in his theory of general relativity published in 1916. If this shortening and stretching were found, then the presence of gravitational waves that Einstein predicted a century ago would be confirmed.

Einstein thought these waves would never be proven, and he even doubted his own theory. But last September, LIGO confirmed the discovery of these waves in the manner that Einstein predicted. LIGO announced its finding earlier this month.

I cannot help but marvel at the immensity and complexity of the universe that LIGO’s discovery of gravitational waves has revealed. According to the news reports I’ve read (see here and here),

  • The LIGO detectors initially could detect distortions in local space-time as small as 1/1000th of the diameter of a proton, but that was not enough to hear these waves—they are even smaller.
  • It would take about 10 trillion of these wave lengths to equal the width of a human hair.
  • The black holes that gave rise to the detected waves were about 1.3 billion light years away from Earth.
  • The collision of these black holes occurred more than a billion years ago.
  • The black holes each packed 30 times the mass of the Sun into a space 93 miles in diameter, and they accelerated at about half the speed of light.
  • The evidence of the gravitational waves are two blips of a signal detected seven milliseconds apart by the two laser observatories, which was first detected in Louisiana and then confirmed at Hanford.
  • When the black holes merged and created the waves, they released 50 times the energy of all the stars in the universe put together.

I’ve read and reread articles describing the finding. I’ve reread my bulleted list above several times since I drafted it. I read it each time slowly and with reverence.

I have to read it slowly to have even an inkling of the awesomeness of a distance of 1.3 billion light years, of seeing (or more accurately “listening”) more than a billion years into the past, of a theory that is proven by something measured in milliseconds. I cannot comprehend the vastness nor the minuteness of the dimensions involved. “Minuteness” does not even describe for me the smallness of what LIGO has measured.

That these things exist is truly awesome. That Einstein could predict them is also awesome. As is our ability to now find them and measure them.

The saying “from my lips to God’s ears” invokes a hope that God hears us. In this case, we have reversed that saying. The LIGO finding has brought us “from God’s lips at creation to our ears.” We now have one more data point for those who must see to believe:

O Lord my God, when I in awesome wonder,
Consider all the worlds Thy Hands have made;
I see the stars, I hear the rolling thunder,
Thy power throughout the universe displayed.

(“How Great Thou Art,” translated into English by Stuart K. Hine)

The creation of a coherent whole from space to atoms, of a mind that can discern the patterns, and of other minds that can fathom how to detect the patterns, all of these must invoke our awesome wonder.

What scientific discoveries awe you?

P.S. According to the Seattle Times, the LIGO operation at Hanford also owns several hay balers, which are needed to bundle up the tumbleweeds that pile up on the service roads around the installation. High tech and low tech. The magnificent and the mundane. Our universe is indeed a beautiful and complex place.

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0 Comments

  1. This is such an interesting post, and I had a similar (awestruck) reaction when I heard this news on the radio as I was driving on the freeway. Thank you for writing about it and for offering some of the important details. I love your phrase, “awesome wonder.” Indeed!

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