Well, it’s about time!!!

What time do you get up in the morning? What time do you go to school? How much time does it take you to eat your lunch? What is your bedtime? What time is it now? We ask questions about time every day. Or rather, to put it differently, we live questions about time every day.

Growing up in the 1970s, 80s, and 90s in the United States, my friends and I mostly used battery powered wrist watches to ‘tell’ time. Nowadays, my middle school students mostly use battery powered smart phones and, most recently, various brands of smart watches. But if you really want accuracy and precision in your time keeping, you will follow an atomic clock.

What is an atomic clock? How can atoms keep time? Watch the creative 2 minute video below and see if it is able to answer some of these questions (and others)…

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Ripple Me This…

We’re all familiar with everyday waves of all types. There’s the Audience (or Mexican) Wave achieved when successive groups of sports fans briefly stand, yell, and raise their arms. There’s Teahupoo, which is located on the southwest tip of Tahiti and widely regarded as one of the most challenging surf breaks in the world. But do you know the most famous wave of all? You probably didn’t, because no one had ever detected its presence…until today, that is.

At a press conference in Washington D.C. on Thursday, February 11, a team of scientists from the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced to the world that they had detected, as Albert Einstein once predicted, gravitational waves. Here’s a link to a video of their official, history-making announcement:


What’s the big deal, you ask? Well, the answer to that question can sound rather complex, and I could start talking about black holes, the Big Bang, the Large Magellanic Cloud, and ripples in the fabric of spacetime, but what I find the most interesting about this discovery has to do with information. Think about radio waves, for example. Radio waves can be used to send information…messages, if you will (think: radio stations in your car). But so can infrared light waves (think: fiber optics), and microwaves (think: mobile phone calls). Now consider the LIGO team’s discovery of gravitational waves. What sort of information might the gravitational waves they detected be carrying? Now, we might be able to better understand why one of the LIGO researchers called this discovery “transformational.”

“We have observed the universe through light so far. But we can only see part of what happens in the universe.” Prof Alberto Vecchio, of the University of Birmingham said, “Gravitational waves carry completely different information about phenomena in the universe. So we have opened a new way of listening to a broadcasting channel which will allow us to discover phenomena we have never seen before.”

Over a century ago Einstein predicted that gravitational waves exist, but until today, no one really knew if they were real. Surely the work of LIGO will go down as the most significant developments in science since the discovery of the Higgs particle in 2012 and, at least according to one news source, is probably on a par with the determination of the structure of DNA. One thing is for certain: the team of lead scientists at LIGO can pop open the Champagne because surely they’ve just earned themselves a Nobel Prize.

Want a little bit more background on this topic and discovery? Give the following videos a viewing…

Science News for Students

PBS Digital Studios

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That Whole General Relativity Thing…

Back in November 2015, interested people around the world (most quietly) celebrated the 100th anniversary of Einstein’s theory of general relativity. American Physicist Brian Greene, whom I once saw speak about string theory in Michigan back in 2002, was among those asked to visit many of the U.S. talk shows to discuss–and explain–Einstein’s epoch making theory. Fortunately, Greene ended up on the show of one of the most entertaining (and smart) talk show hosts in the business, Stephen Colbert. Watch as Greene and Colbert have fun trying to demonstrate some of Einstein’s ideas through simple demonstrations about both gravity and motion.

For me, the best part was at the conclusion, when Colbert asks Greene to explain to him how he (Greene) would explain the warping of the space-time fabric not to the general layperson, but rather to another theoretical physicist. Here’s my transcription of Colbert and Greene’s wonderful exchange, in which Greene provides a fantastic example of what it means to ‘talk’ science…

Colbert: “Give it to me in less than 30 seconds, but let me just lean into my ignorance of what you’re saying to me…”

Greene: “So, Albert Einstein says that space-time is a four dimensional Hausdorff differential manifold on which a metric tensor is imposed that solves the Einstein field equations, and that metric tensor gives rise to geodesics, and objects that are not experiencing any other force will move along the geodesics described by that metric!”


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