relativity
Tag archives for relativity
Putting Einstein to the Test
Posted by Ethan on May 1, 2013 
“The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will…
Black Holes Won’t Incinerate You, After All
Posted by Ethan on March 8, 2013 
“You wait for a gem in an endless sea of blah.” -Lawrence Grossman On the one hand, we have General Relativity, our theory of space, time, and gravity. It describes the Universe on both large and small scales perfectly, from the hot Big Bang to our cold accelerating expansion, from vast superclusters of galaxies down…
Weekend Diversion: The First Relativistic Video Game!
Posted by Ethan on November 11, 2012 
“There is no such thing as magic, supernatural, miracle; only something that’s still beyond logic of the observer.” -Toba Beta It might be hard to believe, but science tells us truths about the Universe that we might never have intuited or philosophized about if the Universe itself didn’t reveal them to us through investigation. Bap Kennedy…
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…
Is Dark Energy the same as Acceleration?
Posted by Ethan on April 10, 2008 In a comment on my last post, What is Dark Energy, Kendall asks the following, which is such a good one I think it deserves its own post: I thought the expansion was accelerating? Aren’t you saying that it is on its way down to 85% of its current rate? Sounds like expansion is slowing,…
Why doesn’t Light Age?
Posted by Ethan on April 2, 2008 There’s a graduate student that I’m sort-of mentoring/working with at Arizona, named Xiaoying Xu (hi Xiao!). She’s bright and curious, and she asks some very good questions. She asked me one yesterday that’s pretty tough to wrap your head around: How do I explain to someone why light doesn’t age? Well, here on Earth, time…
Q & A: What is Energy?
Posted by Ethan on February 25, 2008 Let me set the scene for you: I’m fresh off my Ph.D., teaching introductory physics at the University of Wisconsin. I’m trying to demonstrate how to turn potential energy into kinetic energy, and so I ask this simple question: What is Energy? And I get a stunned silence back from the room. One of those…
Faster-than-light travel: is it possible?
Posted by Ethan on February 4, 2008 Apparently, this is becoming a good place for people to get their questions answered! My friend Brian, recently wanted to know what the possibilities were for faster-than-light travel. Specifically, he was interested in it because he wants humans to do it. Brian: but otherwise how will we ever have a civilization like that in Star…
