Yesterday's announcement was hugely important, and in this writeup (and in the links below) I'm going to try to illustrate how. I hope you'll take a minute to read this, because it's a big deal. If you can't be bothered, at least watch the first few minutes of the video I've embedded above to hear how happy and proud the NSF director is of this achievement, funded by the US taxpayer.
400 years ago, Galileo Galilei obtained an early optical telescope, turned it to the sky and observed the moons of Jupiter for the first time. Noting that the little dots were moving AROUND Jupiter, he realized that things might not all be revolving around Earth, which ultimately had obvious ramifications for science (and theology).
330 years ago, Isaac Newton came up with the mathematical laws that describe the natural motion of objects. Gravity, mass, F=ma ... he laid it all out in Principia, and those laws stood for centuries.
100 years ago, Albert Einstein theorized that "Newtonian" physics was in fact just an approximation, that the reality was that space and time were intertwined, indeed that even energy and matter were interchangeable.
Since then, scientists and engineers have been looking for direct confirmation of all of the effects predicted by Einstein's theories. Some were confirmed very quickly, such as Eddington's confirmation during a 1919 solar eclipse of the effect on light beams, merely 4 years after Einstein's publication. With the advent of the space age in the 1950s, Einstein's theories were then proven correct countless times, and (for example) our GPS system would not function if Einstein were wrong.
But one effect had not been observed: gravitational radiation (gravity waves). The effect was so impossibly weak, even in the theory, that it was just impossible to detect. Even the strongest waves (from black holes annihilating each other) would take ludicrous precision to detect -- measuring the distance to the nearest STAR to the precision of the width of a human hair.
40 years ago, technology had improved to the point that researchers started to think it might be feasible to detect those strongest waves, and so the National Science Foundation started funding development of the technology and systems. Over time, this would become the largest and most ambitious project ever funded by the NSF.
25 years ago, construction started on the first "observatories" (Laser Interferometer Gravitational-Wave Observatory or LIGO), two pairs of long tunnels in the US countryside with sensitive equipment that MIGHT detect the waves. A decade later, in 2002, the system went online, but failed to detect anything for years. In 2009 they upgraded the systems to gain higher senstivity and tried again -- still nothing.
Last fall, they completed another upgrade to the system, now dubbed Advanced LIGO, and very quickly observed their first wave. Five months later, that data has been reviewed and vetted by the community, and they're absolutely sure of it.
Just as Galileo's first telescope changed astronomy forever, and CERN's Large Hadron Collider is providing new insights into quantum physics, yesterday's announcement opens a whole new window into the universe. This is just the very first glimmer of a look at gravitational radiation, and just as optical (and radio, and X-ray, and gamma ray) telescopes have improved over the past centuries, and microscopes have delved deeper and deeper into the minutiae of matter, we now stand at the doorstep to whole new way of looking at the universe, via gravity waves.
The press conference video that I have embedded above really does a fantastic job of explaining all this, even to an average person. Each person speaks for just a few minutes and provides their own video animation to illustrate what this is all about. Watch 3 minutes, watch 10 minutes, watch 30 minutes or watch the whole thing. You will see some of the happiest scientists on the planet, and some of the best video illustrations of what all this about that you will ever find.
USA! USA!
Other links:
The chirp!
https://www.youtube.com/watch?v=egfBaUdnAyQ
Here's a great overview of what happened when in the runup to yesterday's announcement:
https://en.wikipedia.org/wiki/Timeline_of_gravitational_physics_and_relativity
Remember that recent sci-fi movie Interstellar, the one with Matthew McConaughey? Kip Thorne was the lead scientific consultant on it, and he co-founded the first gravity wave detector. He was on the dias for the press conference I link to hear (last speaker) and spoke eloquently of the historical context of this. Here's a lecture of his from 2005 on the topic:
https://www.youtube.com/watch?v=JXaukctamdQ
A neat illustration of the sensitivity of the various systems. Note how improving from LIGO to Advanced LIGO allowed them to dip deeper into the region where the theory said they should detect gravity waves -- and they did!
https://en.wikipedia.org/wiki/LIGO#/media/File:LIGO_detector_sensitivity_curve.png
Last fall, PBS's flagship science program NOVA devoted an hour to describing Einstein's revelations. The entire program is absolutely worth watching, but at least drop in on the last couple minutes (starting at 47m00s) where they discuss what was yet unconfirmed -- gravity waves!
http://www.pbs.org/wgbh/nova/physics/inside-einsteins-mind.html
Georgia Tech computer scientists have already been creating simulations of the binary black hole merger.
https://www.youtube.com/watch?v=pryd0mUmbCM
https://twitter.com/AstroKPJ/status/697808292022718464
Georgia Tech's Laura Cadonati explains what gravitational waves are, how they were observed on September 14, 2015, and why they unlock more secrets of the universe.
https://www.youtube.com/watch?v=tu64i49Y_ps
A quick overview of the significance of yesterday's announcement, produced by Chicago's Adler Planetrium ... "The universe is speaking to us. Up to now, we have been deaf to what is happening."
https://www.youtube.com/watch?v=hGoVqalcST0
Here's the Rochester Institute of Technology crowing about how their computational simulations helped the LIGO team know what to look for. Pretty cool graphics at 1m30s, showing the evolution of the spin vectors as the black holes collide.
https://www.youtube.com/watch?v=BOGOR69HsKM
Some of the scientists did an "Ask Me Anything" on Reddit:
https://www.reddit.com/r/IAmA/comments/45g8qu/we_are_the_ligo_scientific_collaboration_and_we/
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