Physics
drorzel | October 16, 2008One of the annoying things about trying to explain quantum mechanics to a general audience is that the weirdness of the theory forces you to use incredibly convoluted examples. Pop-science books about quantum physics are full of schemes that the producers of the Saw movies would reject as implausibly complicated.
I wish I was posting to say that I had found a way around this, but I haven't. So here's another entry in the thriller-movie school of quantum analogies.
Imagine that you and a friend are out hiking, and find yourselves kidnapped by a sinister conspiracy of some sort. You're taken to…
drorzel | October 15, 2008Today, we have the first claimant of a donation incentive, from Sarah, who asks:
If you could go back in time to any lab and be there as X discovery was being made, which lab/when/where would you go? I figure this could be spun a couple of ways, either to talk about some really cool science or some really interesting personalities/history of science stuff, or both.
She suggests either the modern discovery of BEC, or the Michelson-Morley experiment for a historical entry. Both of these are excellent choices-- I was on the periphery of a group chasing BEC in 1995, and it was an exciting time,…
pontiff | October 14, 2008Garrett Lisi, surfer and creator of possible theories of everything, has given a TED talk:
I had never thought to put Schrodinger into the box.
"I try to balance my life between physics, love, and surfing. That way even if the physics I work on comes to nothing, I've lived a good life." Word.
rallain | October 14, 2008**Pre Reqs:** [Kinematics](http://scienceblogs.com/dotphysics/2008/09/basics-kinematics.php), [Momentum Principle](http://scienceblogs.com/dotphysics/2008/10/basics-forces-and-the-moment…)
What are "numerical calculations"? Why are they in the "basics"? I will give you really brief answer and then a more detailed answer. Numerical calculations (also called many other things - like computational physics) takes a problem and breaks into a WHOLE bunch of smaller easier problems. This is great for computers ([or a whole bunch of 8th graders](http://scienceblogs.com/dotphysics/2008/09/…
rallain | October 13, 2008I went home for lunch today. While waiting, I saw this lizard. We have many lizards in Louisiana, I like them, really I do. So, this is what I did:
No lizards were harmed in the filming of this video.
I was really surprised. I thought for sure that I had tried this before and nothing happened. Maybe it was because of the white surface the lizard was on. Maybe it was because it was an older and wiser lizard (it was larger than normal). Maybe this is already a well known fact about lizards and laser pointers. Needless to say, this was quite entertaining and completely justifies the…
rallain | October 13, 2008There is this show "Weapon Masters" - I think it comes on the discovery channel. It is not a bad show. The basic idea is that they have this history guy talk about the historical aspect of some type of weapon and this other guy tries to make an improved version. Last night the goal was to recreate the original flame thrower mounted on a boat.
They found a boat and they needed to test it's sea worthiness. The builder guy (sorry, I don't know his name) estimated that they would have 1000 lbs of equipment in the boat. To simulate this weight, they put 4 guys and two barrels of water in…
drorzel | October 12, 2008Some time back, I saw Brother Guy Consolmagno talk at Boskone, and said "You know, I should invite him to campus." For those who don't recognize the name, he's an SF fan and an astronomer (well, planetary scientist) who also happens to be a Jesuit brother. He works at the Vatican Observatory, where he is the curator of the Vatican's meteorite collection.
After we were on a panel together last year, I asked him if he'd be interested in giving us a colloquium talk sometime, and he said yes. We exchanged a few emails, and settled on October 9, namely, this past Thursday, when he was going to be…
rallain | October 9, 2008**Pre reqs:** [Free Body Diagrams](http://scienceblogs.com/dotphysics/2008/09/basics-free-body-diagrams.php), [Force](http://scienceblogs.com/dotphysics/2008/09/basics-what-is-a-force.php)
The time has come to look at things that are NOT in equilibrium. The most basic question to ask yourself is: *"What do forces do to an object"*? Aristotle would say that forces make things move. Constant forces make things move constantly. Actually, Aristotle said there were two types of motion:
Natural motions: These motions don't need anything to happen, they just do. Example: a rock falling. You…
drorzel | October 9, 2008In the spirit of the previous post, I thought I would provide a short list of the reasons why I am happy to be a physicist in the area of Atomic, Molecular, and Optical (AMO) Physics. Like nearly anyone who hung on long enough to get a Ph.D. in some field, I think the area I work in is the coolest thing ever, and here are some of the reasons why:
AMO Physics is cool because it's the best field for exploring quantum effects. Pick up a book that deals with fundamental quantum issues-- The Quantum Challenge, say, and look at the experimental demonstrations. Almost all of them come from AMO…
rallain | October 9, 2008Dear Mythbusters. I hope you know that I think you are awesome. I know you are not scientists, but rather master robot builders. I respect that. I envy your robot-building abilities. Please forgive me for pointing this out - but even if a tree is 90% air, that does not mean a ball has a 90% probability of passing through it.
For those of you who are unaware, in the last episode of MythBusters, they explored the idea that a golf ball should pass through a tree 90% of the time. What if they were to test following alternative myth:
*A golf ball has a 90% chance of passing through something…
rallain | October 9, 2008Dear High School students,
How are you? I am fine. I am very glad that I am no longer in high school. Maybe you enjoy high school, but for me, it was not so good. Don't get me wrong, I went to an excellent high school (Waubonsie Valley HS). There was something in high school that didn't feel right. Maybe it was being in classes for too long and the lack of time to work on my own projects. Maybe it was lack of freedom in choosing my own classes (there was some freedom to chose). Or perhaps I was just not mature enough to enjoy it. Needless to say, I am past that now.
I think now, how…
drorzel | October 9, 2008If you go by physics-related stories in the mass media, you'd probably get the impression that about 90% of physicists work at the Large Hadron Collider or some other big accelerator lab. The other 10% would be dominated by people working on foundational questions in quantum mechanics-- Bell tests, teleportation, quantum information processing-- with a smattering of people doing something with superconductors. The distribution in the physics blogosphere is pretty similar.
And yet, if you went by the mass media impression, you'd be way wrong. The largest division of the American Physical…
rallain | October 7, 2008In this post, I am going to talk about real and not real forces as well as the fake centrifugal force (if you don't like the word "fake" you could replace that with "fictitious")
First, an example: suppose you are in a car at rest and press the gas pedal all the way down causing the car to accelerate. What does this feel like? If I weren't skilled in the art of physics, I might draw a diagram something like this:
Yes, maybe someone would add gravity and the chair pushing up, but this shows the…
pontiff | October 7, 2008And the Nobel prize in Physics 2008 goes to...Yoichiro Nambu (1/2), Makoto Kobayashi (1/4), and Toshihide Maskawa (1/4) "for discovery of the mechanism of spontaneous broken symmetry in subatomic physics" and "for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature." I'm buried under work but if I can claw myself out of it I'll write a post about their work. In the meantime, here is the Nobel's scientific background.
drorzel | October 7, 2008I got some interesting comments on last week's post about the science blogging bubble, and there were two in particular I wanted to highlight. Bee wrote (among other things):
But what I think are further obstacle to blogging is the inappropriateness of the medium to science. E.g. blogs put by format an emphasis on novelty, which occasionally disturbs me. There's the option to label posts, but who ever looks at this? I'd vastly prefer to be able if interesting topics stay on top, such that it would be easier to spin longer discussions around a specific topic. Not sure I'm making that very…
drorzel | October 7, 2008Paul Ginsparg, the founder of the arxiv preprint server for physics, has a very nice article at Physics World reminiscing about the rise of the Internet, particularly in physics. This also serves as a nice counterpoint to his talk at the Science21 conference (video, microblogging), which included a wealth of fascinating information about the current operation of the arxiv.
In both of these, he mentions that the arxiv grew out of a pre-existing preprint culture in high-energy theoretical physics. People in the field would make copies of their manuscripts in progress, and send them to other…
drorzel | October 7, 2008The 2008 Nobel Prize in Physics has been announced. Half will go to Yoichiro Nambu "for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics," with the other half split between Makoto Kobayahi and Toshihide Maskawa, "for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature."
I'll be honest: this is far enough outside my area of physics, that I can't say anything sensible other than "It's a good day to be a Japanese particle theorist." I can't begin to explain what these guys did. The…
rallain | October 6, 2008Popular demand (from a few people - you know who you are) requested another level for the force game. I am open to naming this game. Ideas for levels have been suggested also. There is a new rule change. You must be stopped (or almost stopped) in the red circle.
Learn more about this project
Update:
I guess I didn't include instructions on how to play the game. Just click on the applet window to make sure it is active. Press the space bar to start the game. Once the game starts the objective is to use rocket thrusters (the arrow keys) to move the rocket (the black rectangle) into the…
rallain | October 6, 2008**Pre reqs:** [Free body diagrams](http://scienceblogs.com/dotphysics/2008/09/basics-free-body-diagrams.php)
Friction is an interaction between two objects in contact that opposes relative motion of those two objects. It is not something fundamental (like gravity, or electromagnetic force), but it comes up enough that it will be worthwhile to talk about it. Let me start with a simple example. Suppose I have a book on a table. Here is the free body diagram for the book:
Simple enough - right? There…
rallain | October 6, 2008I already said I like [scratch from MIT](http://scratch.mit.edu). After building a simple rocket model, the kids said it should be a game. I caved. Here it is:
Learn more about this project
To play, press the space bar. The arrow keys are rocket thrusts. The goal is to get to the red circle in as little time. If you hit the wall or the sides, you start back at the green circle. Please forgive me masters of scratch (I know who you are - you find something to complain about in my program).