By Christopher Moore
I received the following email over the weekend from a concerned brother who wishes to assuage his young brothers fears. The question is one that I’m sure we have all thought about from time to time: Will you die if you see yourself headless in a plane mirror? The answer may surprise you.
First, the email:
Hi there, my name is Jason and i saw your email adress from your website Ilovephysics.com, I seek your knowledge in order to help my brother, my brother is convinced of the superstition that “IF you see yourself headless in a mirror, You will die” This is very irrational but he is convinced with it making him paranoid and dillusional, it distracts him and i hate seeing him suffer from irrational fears, unfortunately, i do not know much about light reflection.
so i was wondering if you could explain how and image is formed in the mirror and WHAT guarantees reflection? what makes it so mirrors would always be making Images with your HEAD intact. so that my brother will be convinced that No matter what you would always be seeing yourself with a head in the mirror.. and it would be helpful if you could also give me proofs of the statements you will provide.
i very much hope to hear from you. thanks in advance
First, the unfortunate truth is that we all die whether we see ourselves headless in the mirror or not. It is just a question of when — maybe 70 years from now. Can seeing yourself headless in the mirror speed up the process, though?
If you look into a regular plane mirror and you see your headless body in the reflection, then you probably should be worried. Something strange is going on, indeed. However, I would not worry too much, since the likelihood of encountering yourself decapitated is practically zero. You see, in order for the mirror to portray an image of a headless person, there has to actually BE a headless person standing in front. It is not the act of looking into the mirror that causes death, but whatever chopped off your head in the first place. Besides, how can you “see” yourself in the mirror when your eyes are still sitting in your head, which is … well … somewhere else.
So, I guess, the answer to the question is yes. If you see yourself headless in a plane mirror (no tricksies), then I think it is safe to say that you are most likely headless in real life and you will die rather quickly.
Concerning your questions about reflection and mirrors in general: unfortunately this is a topic that generally takes at least a few days out of an introductory physics course, so I can not do the topic justice in an email (or blog post). I suggest posing questions in the forum, or reading the optics section of a good introductory physics book. The links below will take you to a few free ones online:
http://www.motionmoutain.net
http://www.lightandmatter.com
If you have an interesting question that you would like a physicist to address, then feel free to shoot me an email as well.
By Christopher Moore
Do you visit ilovephysics.com or are you a Phan of Physics? Place yourself on the Physics Phan Map. Click on the map below and tell us where you live (just the city, we’re not coming to your house or anything). A big red dot will be placed on the map just for you.
By Christopher Moore
On Tuesday January 30th, we welcomed a brand new physicist to the family. At 2:17 pm Christopher Balin Moore was born and immediately began studying gravity and parabolic motion. Unfortunately, my flight from Pittsburgh to Richmond landed at 2:22 pm. I may have missed the actual birth, but at least I have the rest of my life (hopefully) to spend with this little guy.
I’ve been out of town on job interviews for several weeks. Since Balin’s due date was not until Feb. 12th I scheduled all of my interviews to end by the 30th of January. That should have left plenty of time to make sure I was there for the birth, right? Nope. Thankfully the physics faculty at the small college where I was interviewing were understanding and worked hard to get me to the airport early. Balin was itching to come out, though, so I missed him by about half an hour.
Notice the rocket ships on his shirt. We begin calculus lessons in a few weeks!
Here are the stats:
Weight - 6 lbs. 13 ounces
Length - 19.5 inches
By Christopher Moore
I hope everyone has a great 2007!
I’ve been fairly busy recently with research. However, I have a few new articles I’m working on that I’ll start posting soon. Also, I recently fixed a problem with the forum — learn more here.
By Christopher Moore
ilovephysics.com was featured in the November 3rd, 2006 edition of Science Magazine’s “Best of the Web in Science.” Under the “education” sub-heading, the editors at Science have this to say about my simple little website:
The target audience for I Love Physics is everyone from students struggling with their homework to professors looking for timely examples for the classroom. The site from J. Christopher Moore, a teacher at Virginia Commonwealth University in Richmond, includes a forum in which students from high school through college level post and chew over baffling problems. In the blog section, Moore explores topics that include cheaper alternatives for fuel-cell catalysts and the optimum angle for punting a football.
First, a clarification: although I was a teaching assistant while working on my M.S. in Applied Physics and I have been an adjunct for laboratory sections, I do not currently teach at Virginia Commonwealth University (VCU). I am a research assistant finishing my Ph.D. in Chemical Physics, which means I haven’t taught a section at VCU for several years. I have taught introductory courses in physics at St. Catherine’s School and J.R. Tucker High School, though.
Second: I’m pretty excited that Science finds this site worthy enough for discussion. I consider that one hell of a compliment.
For those that found this site via Science, feel free to poke around and join in the discussions in our forums. Also, check out some of our videos to get an idea of how talented physics students are here in Richmond, VA. 
By Christopher Moore
ilovephysics.com has been experiencing explosive growth. Last summer, we were averaging about 7,000 visitors per month. During the fall semester, I let the site slip for a bit and readership dropped to about 4,000 visitors per month. Google also stopped crawling the site for several months for reasons still unknown, but last month they came back. Starting in January, readership has been growing. Here’s how much:
Month
January
February
March
April |
Visitors
3,801
4,750
8,696
11,185 |
From our logs for today, we’re on track to receive over 12,000 visitors this month.
This many Physics Phans is encouraging. With the help of all 12,000 of you, we can certainly change the culture of education and usher in a rebirth of strong math and science in our schools.
By Christopher Moore
Try this: go to Google and type in “Caveman Science“.
Look which site pops up first in Google’s index! Pretty neat.
Other cool keywords: The obvious “I Love Physics“.
And we almost have wikipedia beat on this one: “superatom“.
By Christopher Moore
The other day I wrote about the website face lift. Here is a little update.
Concerning ads: I cut the number of ads served per page in half. And as I predicted, the ad revenue has doubled! It is weird, I know. This doesn’t mean the site is raking in the dough. Double the ad revenue per day buys an extra pack of gum. So I still have my hand out and a sign that says “will do physics problems for food.” At least I do not have to worry about starving my dogs so that I can pay my bandwidth bill.
Integrating the forum: For a few days, if you used most versions of Internet Explorer you would have had a pretty hard time reading the forum. The text was tiny! It looked great in Firefox, Safari, and Opera, but IE just couldn’t handle it. I fixed that. Image upload apparently is still not working for IE though. I will be fixing that. Another reason to Get Firefox.
Writing the tutorials: I have been busy writing physics tutorials. You can of course see what I’ve done so far by clicking the “Tutorials” link above. I will be updating them daily. Feel free to leave comments about what I have up so far. I’ve enabled comments for each page. When I’m all done, I’ll be publishing a print version for those who are interested. If your comments prove to be significantly useful, you’ll get a mention in the acknowledgements.
Other projects in the works: Each section of the tutorials will be accompanied by an online, graded quiz and a video demonstration or two. I’m working on adding many more problems to the Solution Generator. And I’ll get back to writing about common misconceptions in physics real soon.
That’s it.
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