cosmological
Tag archives for cosmological
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 The Entire Universe Is Made Of, Thanks to Planck!
Posted by Ethan on March 21, 2013 
“Much later, when I discussed the problem with Einstein, he remarked that the introduction of the cosmological term was the biggest blunder he ever made in his life. But this “blunder,” rejected by Einstein, is still sometimes used by cosmologists even today, and the cosmological constant denoted by the Greek letter Λ rears its ugly…
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…
Say Something Smart
Posted by Ethan on August 27, 2012 
“You must learn to talk clearly. The jargon of scientific terminology which rolls off your tongues is mental garbage.” -Martin H. Fischer I’ve always thought that the Universe is absolutely amazing; that everything from the tiniest indivisible particles all the way up to the largest structures and superstructures making up the Universe has an amazing…
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!…
