cosmic
Tag archives for cosmic
The Beginning of the Universe and the Limit of Knowledge
Posted by Ethan on April 19, 2013 
“Despite its name, the big bang theory is not really a theory of a bang at all. It is really only a theory of the aftermath of a bang.” -Alan Guth So you finally understand it. The Big Bang tells us that the Universe was hotter, denser, and expanding at a faster rate in the…
Inflation, Dark Energy, and the Physics of Spacetime
Posted by Ethan on April 12, 2013 
“Orbiting Earth in spaceship, I saw how beautiful our planet is. People, let us preserve and increase beauty, not destroy it!” -Yuri Gagarin Fifty-two years ago today, the first human being left Earth, and we began our journey into outer space. But back in 1961, we didn’t really know how far outer space stretched, or…
What Happened Before The Big Bang?
Posted by Ethan on October 15, 2012 
“The aim of science is not to open the door to infinite wisdom, but to set a limit to infinite error.” -Bertolt Brecht One of the most frequent questions I get about the Universe — as a cosmologist — isn’t quite about the Big Bang in and of itself. The Big Bang is a remarkable…
The Cosmic Story of Carbon-14
Posted by Ethan on June 4, 2012 
“Life exists in the universe only because the carbon atom possesses certain exceptional properties.” -James Jeans Here on Earth, every living thing is based around four fundamental, elemental building blocks of life: hydrogen, oxygen, nitrogen and, perhaps most importantly, carbon. From diamonds to nanotubes to DNA, carbon is indispensable for constructing practically all of the most intricate…
Hole in the Universe? What Hole?
Posted by Ethan on May 20, 2008 Some of you who’ve been following astronomy for awhile might remember this report, where a group of astronomers reported finding a giant “void” in the Universe. What is a void? Well, galaxies are distributed pretty randomly, but because of gravity, they cluster together. A small example is our local group which looks like this, and…
Astronomers make use of… molecules?
Posted by Ethan on May 14, 2008 When I think of molecules, I think of Conan O’Brien doing his skit where he plays Moleculo… the molecular man! I don’t think of astronomy, and I certainly don’t think of the leftover radiation from the big bang (known as the cosmic microwave background)! But somebody over at the European Southern Observatory put these two…
Cosmic Sound Waves… Rule?
Posted by Ethan on April 25, 2008 So as a full member of both the American Astronomical Society and the American Physical Society, I get sent issues of the magazine Physics Today. Well, I was going through the April issue, when I saw this article: Cosmic Sound Waves Rule by Daniel J. Eisenstein and Charles L. Bennett That first name sounds familiar.…
How to Destroy the Entire Universe
Posted by Ethan on April 23, 2008 Since the dawn of time man has yearned to destroy the sun. – C. M. Burns There’s no need to stop at the Sun, though. Since yesterday was Earth day, I thought it was only appropriate to spend today telling you how not only to destroy the Earth, but to effectively destroy the entire Universe.…
WMAP results: Cosmology from the CMB
Posted by Ethan on March 6, 2008 The cosmic microwave background is the radiation left over from the big bang. It’s very uniform, 2.725 Kelvin everywhere. We’re moving with respect to it, so there’s a doppler shift, and we see that as a dipole moment in the Temperature. When we subtract that out, we see variations on the order of 30 microKelvins!…
