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By Christopher Moore
Here is a funny article about one man and his grassroots campaign to re-elect Pluto to the family of planets.
“Take a look at the campaign signs in Erik’s yard,” a friend advised Bill Brent.
“Is it a local issue,” Brent asked, “or national?”
Actually, he was told, it’s kind of universal.
Erik Kilk is campaigning for Pluto.”
His site is here.
I’m going to look into getting some yard signs of my own. Needless to say, ilovephysics.com officially endorses Pluto for the position of 9th Planet in the Solar System.
By Christopher Moore
 NFL teams are currently battling it out in pre-season games, and college teams are gearing up for the beginning of the season. The NFL Regular Season starts 9/7/2006 and ends with Super Bowl on 2/4/2007. That makes this the perfect time to ask football coaches for a job. That’s right. Every football team needs a physicist on staff. If John Fox of the Carolina Panthers or Frank Beamer of the Virginia Tech Hokies are reading this, then sirs, I am ready. Put me in coach.
I know Frank Beamer puts special emphasis on special teams, so I thought I’d help out by providing his punters a little physics lesson:
Rob Gross sent me an interesting article he wrote where he examines the optimum punting angle to maximize net yardage. Here is the introduction:
Using elementary physics, one can easily show that the optimum angle to launch a projectile in order to maximize its range is 45 degrees when air resistance is ignored. Thus when applied to a punt, the kick will travel the most distance when it is kicked at an angle of 45 degrees. However, the analysis is not the same when trying to fnd the optimum angle to maximize the net yardage of a punt. For instance, if the punt is kicked at a greater angle the punt will be in the air longer and will allow the kicking team to get closer to the punter and thus limit his return. However, kicking at this greater angle will also shorten the kick. I will analytically examine this compromise.
Click here to download the entire article.
In the article, Rob develops an equation for optimal punt angle as a function of the speed of both the defense and offense. By using some rough estimates of average player and punt velocity, he comes to the following conclusion:
The optimum angle to maximize the net yardage does depend weakly on the average speed of the punt returner and the speed of the football. However, for realistic speeds, the dependence is so weak that it is very close to 45 degrees and a punter does not have tolerance when kicking to distinguish these angles. Not only is the angle extremely close to 45 degrees, if one could actually kick at that angle, the angle has almost negligible affect on the net return. Thus, to maximize net yardage, the analysis is practically the same as the maximal range angle and the punter should punt at an angle close to 45 degrees.
Rob simplifies the real problem quite a bit. You also have to consider field position. You want to land the ball somewhere between the 20 yard line and the goal line, ideally right on the 1 yard line, to avoid a touchback. (See Frank Beamer, I know a thing or two about football. I’m available if you need me.) But overall, getting your guys to the other end of the field before the ball is caught will usually result in a “fair catch” call, and this is rarely good for the opposing team.
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By Christopher Moore
Only a few days ago I wrote about how Pluto’s status as a planet was not only solidified, but that three other planets were added to the solar system. Well …
Capping years of intense debate, astronomers resolved Thursday to demote Pluto in a wholesale redefinition of planethood that is being billed as a victory of scientific reasoning over historic and cultural influences.
MSNBC.com reports the result of a vote at the International Astronomical Union in Prague, and the results are not good for Pluto, Charon, Xena, and Ceres. Only 424 astronomers voted on the very last day of the conference to redefine the meaning of the term “planet”:
Planets: The eight worlds starting with Mercury and moving out to Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Dwarf planets: Pluto and any other round object that “has not cleared the neighborhood around its orbit, and is not a satellite.”
Small solar system bodies: All other objects orbiting the sun.
Dwarf planets are not considered plantes, according to the resolution. Sorry Pluto. We know you have been an honorable member of the family of planets for over a century, but … well… get over it.
Some astronomers where upset, considering that the number of voters made up only 5% of all astronomers. Alan Stern, a NASA scientist, has said the language of the resolution is flawed by requiring that a planet “has cleared the neighborhood around its orbit.” Earth, Mars, Jupiter and Neptune all have asteroids as neighbors. So a case could be made that they are not planets according to the new definition?
“It’s patently clear that Earth’s zone is not cleared,” Stern told Space.com. “Jupiter has 50,000 Trojan asteroids,” which orbit in lockstep with the planet.
Stern called it “absurd” that only 424 astronomers were allowed to vote, out of about 10,000 professional astronomers around the globe.
“It won’t stand,” he said. “It’s a farce.”
Strong words. My prediction is that this conflict will never be resolved.
By Christopher Moore
William Shatner has been gaining in popularity for some reason. Most people I talk to agree that he is a terrible actor. But he was also Captain Kirk. So whether you love him or hate him you have to accept that his imprint will be large and loud in Science Fiction for many years to come. If you love him, then you’re going to definitely want to continue reading. If you hate him but still love science fiction, then continue as well.
Shatner now has a Sci-Fi DVD of the month club and he’s giving away a free Sci-Fi movie just for giving it a look:
Get Your Free Sci-Fi Movie From William Shatner!
If you love Shatner, then this is a no brainer.
But I did say even if you hate the man as an actor and Sci-Fi figure, you should keep reading. The reason: this actually looks like a really good deal.
Shatner explains his new club as follows:
Determining what movies get broad distribution and studio marketing support is a complicated process, and unfortunately the caliber of the film isn’t the only consideration. I’ve chosen a select group of memorable and entertaining sci-fi movies that never got the exposure they deserved, and made them available to fans everywhere at a great price.
So you aren’t likely to receive Star Wars or Starship Troopers on DVD with his club, but if Sci-Fi is your thing, as it is mine, then a new movie evey month sounds pretty cool. They may be great. They may suck. But I’m willing to bet that most are at least entertaining. Here’s a little more straight from the source:
While many of the films distributed by the William Shatner DVD Club have names that the casual fan may not recognize, those few fans who have seen these movies agree that they are underground hits. For example, in IMDB, the following three recent movies received the same rating: Vanilla Sky, Terminator 3: Rise of the Machines, and Ginger Snaps. Terminator 3 grossed $418 million at the box office. Vanilla Sky topped over $200 million during an impressive theater run. And Ginger Snaps? Ginger Snaps grossed a whopping 146,125 Spanish Pesatas in a brief European engagement before becoming an afterthought in a crowded sci-fi market. And most American movie fans missed out on one of the best sci-fi films of the last five years.
Ginger Snaps was the first movie William Shatner included in the club, but it is not the only great movie with an unfamiliar name available to members. Close Your Eyes, a sci-fi thriller, won three awards at the Paris Film Festival in 2004, and took home top honors from the Swedish Fantastic Film Festival in 2002. Richard Roeper (of Ebert & Roeper) raves about Close Your Eyes, “”One of the best thrillers I’ve seen probably since The Ring.” Immortal (Ad Vitam), a film which was never released in U.S. movie theaters, has been called “jaw dropping, highly detailed, and smoothly executed” and “strangely and almost hypnotically engaging”.
Ginger Snaps, Close Your Eyes, and Immortal have all made apperances as Shatner’s movie of the month. I’m going to give Shatner a shot and see if he can make some good picks. Here’s why:
* I get a free movie just for giving Shatner a shot. If he sucks at picking them, then he gets no money from me.
* One film every month for only $49.95 per year. That’s CHEAP. We’re talking $4 per DVD and I get to keep them.
I’m going to give it a go. I’m no Shatner fan. I’m not even into the original Star Trek. But the price is great and it looks like there is some pretty awsome Sci-Fi coming my way.
Check it out for yourself:
Get Your Free Sci-Fi Movie From William Shatner!
By Christopher Moore
Electromagnetic radiation (or light) sometimes behaves as a particle and sometimes it behaves as a wave. The same observations are made with regular particles like electrons. This apparent contradiction has led many to question the foundation of modern science, specifically quantum theory. How can something be A in one instance and be B in another? The answer is: that something is neither A or B.
First off, a little history. In around 1805 Thomas Young performed an experiment that has come to be called Young’s Double-slit experiment. Wikipedia summarizes the experiment as follows:
The double-slit experiment or two-slit experiment consists of letting light diffract through two slits producing fringes on a screen. These fringes or interference patterns have light and dark regions corresponding to where the light waves have constructively and destructively interfered.
Young was attempting to determine whether light was made up of particles or whether it was made up of waves. That he observed an interference pattern lead him to the conclusion that light was a wave. It wasn’t until the early 20th century that experiments began to suggest that light was made of particles. Einstein’s photoelectric effect is an example of light “behaving” like a particle.
So in some instances light behaves like a wave, but in others light behaves like a particle. And to further complicate the matter, Young’s experiment can be performed using beams of electrons or atoms. So particles seem to act like waves sometimes as well!
In 1961, Claus Jönsson of the University of Tübingen performed the Young experiment with a steady stream of electrons, and in 1974 the experiment was carried out “one electron at a time” at the University of Milan by Pier Giorgio Merli.
Here are the results (whether done with electrons or light):
If either slit is covered, the individual photons hitting the screen, over time, create a pattern with a single peak. But if both slits are left open, the pattern of photons hitting the screen, over time, again becomes a series of light and dark fringes. This result seems to both confirm and contradict the wave theory. On the one hand, the interference pattern confirms that light still behaves much like a wave, even though we send it one particle at a time. On the other hand, each time a photon with a certain energy is emitted, the screen detects a photon with the same energy.
A remarkable refinement of the double-slit experiment consists of putting a detector at each of the two slits, to determine which slit the photon passes through on its way to the screen (If the photon or electron passes through only one slit - which it must do, as, by definition, a photon or an electron is a quantum, or “packet” of energy which cannot be subdivided - then logically it cannot interfere with itself and produce an interference pattern). When the experiment is arranged in this way, the fringes disappear.
This is truly remarkable and seems to be completely contradictory. What this suggests is that light (or electrons) behave like waves unless we start counting them, and then they behave like particles. Observing things affects their behavior it would seem. The Young experiment applied to particles directly resulted in the development of quantum physics.
Some consider this a glaring contradiction, and therefore doubt the validity of quantum theory. They suggest that one thing cannot exhibit two very different behaviors based on the circumstance. Unfortunately for them, the experiment is very reproducible. Quantum theory doubters base their arguments on a misconception of what may really be going on: they continue to view the world through Newtonian glasses, where particles are particles and waves are waves.
One of the moderators on our forum puts it this way:
We call something a particle if it behaves in a particle-like manner. But what does that mean? What is particle-like behavior? Similarly, we say that something is a wave if it exhibits wave-like behavior. But what do we mean by that? What is wave-like behavior? Whatever your answers, they will be drawn from pre-20th Century (“classical physics”) constructs for describing the physical world that we observed. They are models originally distilled and codified from early observation and experiment.
A model is only as good as the accuracy of its results, and when investigating very small particles, classical models and descriptions no longer hold. An electron will behave differently depending on the circumstances. The common misconception is that this is contradictory, that something has to be either a particle or a wave. It is not contradictory. The wave-particle duality “problem” is only an issue if you continue to wear a Newtonian mental straightjacket and believe that only one of two types of behavior can be valid. Those who found an argument against quantum theory on this premise need merely be pointed to experimental data.
Martin once again:
Perhaps a reasonable analogy might be a coin: It has two sides (heads and tails). When you flip the coin, it will land showing either the heads side or the tails side, but not both. You would not be at all perplexed by this: Even though sometimes you see the heads side but other times you see the tails side, you have no doubt that you’re looking at a coin. The coin is then analogous to a “wavicle” of light, which has two mutually exclusive properties: sometimes it shows its “wave” behavior, sometimes its “particle” behavior.
Our Newtonian blinders confuse us. We are conditioned to think in terms of hard particles (like baseballs) and soft waves (like water ripples). This is what we see all around. It is easy to assume that smaller objects should exhibit similar behavior, but that assumption is absolutely false. George Gamow coined the term “wavicle” to describe quantum entities that exhibited both wave and particle behaviors. The conclusion that can be drawn from the data is that an electron is neither a wave or a particle. It is neither A or B. It is something else completely.
It is a wavicle.
By Christopher Moore
Millions of textbooks across the globe currently report the existence of 9 planets. But it appears that the International Astronomical Union has decided that actually defining the term “planet” is a good idea and plan on doing it at their annual general assembly later this month.
The problem? The (as of now) popular proposal of a definition would require editing all of those textbooks. And, of course, has sparked a heated debate. The proposal would add three new planets to our solar system! Here’s the definition:
“A planet is a celestial body that (a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (b) is in orbit around a star, and is neither a star nor a satellite of a planet.”
So what this means is that any object that orbits the sun and is round is a planet. That’s good news for Pluto. It gets to remain a planet. It’s also good news for the asteroid Ceres, which happens to be round. Ceres, which can be found between Mars and Jupiter, was originally deemed a planet when it was discovered in 1801, but it was re-classified as an asteroid. Maybe now it can regain respect and re-join its bigger brother planets.
MSNBC.com reports about the shake-up in Solar System hierarchy:
The asteroid Ceres, which is round, would be recast as a dwarf planet in the new scheme.
Pluto would remain a planet, and its moon Charon would be reclassified as a planet. Both would be called “plutons,” however, to distinguish them from the eight “classical” planets.
A far-out Pluto-sized object known as 2003 UB313, currently nicknamed Xena, would also be called a pluton.
If the definition gets the nod, the solar system would instantly sprout three new planets. But under the new definition, nearly a dozen other objects may qualify as planets as well. From MSNBC.com:
If astronomers determine that asteroids Pallas, Vesta, and Hygeia are also round, “they will also have to be considered planets,” said Owen Gingerich, a historian and astronomer emeritus at Harvard. The IAU proposal suggests (but does not require) that these be called dwarf planets. Pluto could also be considered a dwarf, which the IAU recommends as an informal label.
That’s a lot of planets.
I’ll leave you with the lyrics to 2 Skinny J’s song “Pluto” after the jump.
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