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Category: Physics
Robots! Clean Your Drives Daily: PSA's from the Future
Via Hero Complex come these ingenious public service announcements and travel posters from a near future in which time travel is possible and robots are self-cleaning. Designed by artist Amy Martin, the posters are $20 each and proceeds benefit 826LA, a non-profit writing center for kids 6 to 18.
Comic-Con 2009: Bask in the Audio Charm of Dr. Who, David Tennant
Going to Comic-Con is awesome on many levels, but going as press is, if you’ll forgive my butchery of the English language, even awesomer. Not that we keyboard-stained wretches get into crowded events more easily than everyone else—Comic-Con is remarkably egalitarian that way—but we do get the opportunity to interview some of our favorite actors, directors, and creators. Some of those interviews I’ll be publishing as blog posts in coming weeks, but I thought I’d share the interviews with the of Doctor Who folks right way.
Comic-Con 2009: Physics Goes to the Movies
Spiderman, Iron Man, and Captain Kirk might be able to take on the villains of the universe, but they’re no match for a physicist. At yesterday’s Comic-Con panel The Physics of Hollywood Movies, Adam Weiner*, a high school physics instructor and author of Don’t Try this at Home! The Physics of Hollywood Movies gauged the scientific accuracy of favorite sci-fi, superhero, and action-movie scenes:
Among the things we learned:
- X-Men’s Storm would need to consume 120,000 in food calories or have a nuclear reactor in her stomach to generate the minimum 500 million joules of energy needed to shoot lightning bolts from her body. On the plus side, such a metabolism definitely helps one stay in movie shape.
- In Mission Impossible, Tom Cruise survives a 2,200-g mid-air body slam (where g is the acceleration due to Earth’s gravity, 9.8 meters per second squared), but Newton’s second law doesn’t fare so well. “A force to the head exceeding 150 g’s is usually fatal.” Usually, sure. All that Scientology in his noggin probably helped cushion the blow…
- Read More
Behind the Scenes & Under the Hood: Virtuality's Antimatter Spacecraft Engine
Today we present a very special installment of the Codex Futurius, Science Not Fiction’s look at the big scientific ideas in sci-fi: Kevin Grazier—JPL physicist and friend of SNF—gives an insider’s peek at the workings of and discussion around the Orion antimatter drive used to propel the Phaeton starship in Ron D. Moore’s recent TV movie, Virtuality. Grazier was a science adviser for the movie (which was intended to be the pilot for an ongoing show), so he was right in the middle of these discussions. The screenshot further down in this post shows the actual spreadsheet used in the production to see what stars would be reachable with the Orion drive. Without further ado, here’s some sci in your sci-fi:
DISCOVER: What kind of realistic technology could we use to get to nearby stars? Which stars would be feasibly reachable by such technologies?
Kevin Grazier: It’s a saying plastered on T-shirts and bumper stickers—the kind sold at both science-fiction conventions and physics departments nationwide:
186,000 miles per second:
It’s not just a good idea, it’s the law.
The speed of light, of all electromagnetic energy, in a vacuum is the ultimate speed limit in the universe. Nothing that has mass or carries information can travel faster.
This universal speed limit is a direct fallout from Albert Einstein’s special theory of relativity. Special relativity implies that the speed of light in a vacuum is a universal constant, but values that we tend to think of as constant in our daily experience—mass, length, and the rate of the passage of time—are not. Depending upon the relative velocity of two observers, these values will “adjust” so that both observers see the speed of light as a constant. Two observers travelling at high speeds relative to each other will find themselves in strong disagreement about measurements like the length of each other’s spacecraft and the rate of the passage of time.
Another consequence of special relativity is that, as an object travels increasingly faster, it behaves as if it has increasingly more mass. Therefore the amount of thrust it takes for an incremental change in velocity (known in the space program as a delta-V) is vastly greater at high speeds than at low. This effect is also highly nonlinear: It takes almost an order of magnitude more thrust to accelerate from .9c (nine-tenths of the speed of light) to .99c than it does to accelerate from .5c to .7c. An object travelling at the speed of light would act as if it had an infinite amount of mass and it would, therefore, require an infinite amount of energy (read: an infinite amount of thrust/fuel) to attain it.
This is, of course, a shame for civilizations (like ours) who want to explore planetary systems around other stars first hand. The distances involved are, well, astronomical. Just within the Solar System, it typically takes NASA probes 6 months to a year to reach Mars; it took Cassini 6 years, 9 months to reach Saturn. The (currently) fastest object created by humankind, the Voyager 1 spacecraft, will take 40,000 years, give or take a few thousand years, before it makes its closest encounter with its first star: AC+79 3888—currently located in the constellation Ursa Minor. At that speed few Time Lords, and even fewer humans, would survive the journey to even “nearby” star systems.
Lost: Faraday Cages
Wednesday’s night’s episode of Lost was a clip job, leaving unanswered some burning questions about the show’s resident physicist, Daniel Faraday, that we hope will be answered soon.
One question that had occurred to me can be answered. Is Daniel a descendent of Michael Faraday, the 19th century English physicist, chemist and (until recently) featured star on the back of British 20-pound notes? The writers of Lost like to have fun with historical names (John Locke and Jeremy Bentham, for instance, and Daniel Faraday’s own mother, Eloise Hawking). But the original Faraday had a special interest in electromagnetism, so the thought crossed my mind: Could Daniel be his great-great-great-grandson?
Codex Futurius: Transparent Aluminum
Michael D. asked, on the Assignment Desk post:
In the most recent issue of Nature, there are two papers…that detail the characteristics of sodium and lithium under extreme pressure. Specifically, these two metals adopt semiconductor-like (even superconductor-like) characteristics if you subject them to giga-pressure (literally, 80-200 gigapascals). The sodium actually becomes optically transparent during this squeeze. Reading this reminded me of a Star Trek [movie] that involved a not-so-scientific explanation of “transparent aluminum” …Is the idea of using transparent metal for windows pure science fiction?
The paper you’re talking about, the one on high pressure sodium, sure did make a lot of noise in the science world, and for good reason. Drs. Yanming Ma and Artem Oganov at SUNY Stonybrook showed that lithium and sodium do goofy things under pressure — like turn transparent. Normally under really high pressure, elements turn into metals, c.f. hydrogen. The science makes intuitive sense because the atoms are getting smooshed together as the pressure increases. The electrons are freed to become conductors, and the element takes a metal-like structure. But in sodium, it turns out, the electrons line up into columns, one on top of the other. This creates gaps between the atoms, and instead of becoming a conductor, it becomes an insulator, and, conicidentally, becomes transparent.
All of which is cool, but it doesn’t really answer Michael D’s question, because the sodium is under 200 gigapasacals of pressure, the sort of pressure you find if you were journeying from Jupiter’s surface toward its core, not hanging out on the bridge of the Enterprise.
And yet! That formula Scotty gave for transparent aluminum in Star Trek IV: The Voyage Home very nearly exists in the form of aluminum oxynitride (known as ALONtm). Harder than diamond, ALONtm is far more shock resistant than even bullet resistant glass. In Air Force tests it has resisted multiple rounds from a .50 caliber sniper rifle. That hardness also prevents wear and tear, since neither sand nor rocks nor shrapnel in the night will scratch the stuff.
In practical use, the ALONtm would be the outer layer for windscreens of cockpit covers. It would be backed by a thin layer of glass and a layer of transparent polymer to prevent shattering. All together the ALONtm windscreen would be thinner and lighter than a traditional bullet-resistant windscreen.What’s unclear from my research is whether it would be strong enough to hold back enough water to make the aquarium for all those humpbacks whales on a captured Klingon spaceship, but it’s a start.
The main downside? It’s wicked expensive. Traditional bullet resistant glass goes for $3 per inch-squared, but ALONtm costs between $10-$15, or it did back in 2005. I can’t seem to find any more current applications for it, but this is the military, it could be classified.
Anyway Michael D., I hope that answers your question.
Codex Futurius: Teleportation
In this installment of Science Not Fiction’s Codex Futurius project, we pose the question:
I want to have a teleporter in my story. How would one work?
The good news is that a working teleportation device already exists. The bad news is that it won’t work for you if you happen to be bigger than a rubidium atom—but scientists are toiling away to fix that. As physicist Michio Kaku noted last year in DISCOVER, we could be teleporting things as big as a virus within a few decades, which means we would be ready teleport a person around the 23rd century, just in time for the predicted construction date of Captain Kirk’s Enterprise.
Diamonds In The Sky: Universal Alchemy
Continuing on with our look at short stories of the Diamonds In The Sky online anthology, we turn to “The Freshman Hook Up” by Wil McCarthy (McCarthy wrote an article for the October 2008 issue of DISCOVER about the very real possibilities of the programmable matter that appears in many of his science fiction books).
The Freshman Hook Up is a wry take on the phenonmenon of stellar nucleosynthesis–a phenomenon to which we owe our existence. After the Big Bang, most of the ordinary matter in the universe formed into isotopes of hydrogen, helium and a smattering of lithium. Heavier elements—making up nearly all of the periodic table—simply did not exist. So how is it that we can stand on a planet mostly made of rock, and enjoy active biochemistries that rely on carbon, oxygen, nitrogen along with some other elements?
Is "Big Bang Theory" Bad for Science?
I know that many scientists (and at least one science blogger) really like the CBS sitcom The Big Bang Theory. The show is well-written and acted, has a half dozen funny one-liners per episode, and delivers a weekly helping of science and nerd culture in-jokes.
In a recent episode, Howard the NASA scientist erased several hours of data from the Mars Rover after inviting a woman he had met in a bar to come back to his office and drive it. His pick up line: “Have you ever driven a car …. on Mars?” Funny stuff and mostly harmless, right?
No. Not right. After watching several episodes on a recent cross-country flight, I’ve concluded that this show is bad for American Science. And here’s why:
Knight Rider: Seeing Through Walls With Infrared Glasses?
Will someone please explain how this whole infrared-can-see-through-walls thing got started? It comes up everywhere: James Bond used it, One of the iterations of CSI used it, then KITT used it on last night’s episode of the New and Improved Knight Rider (now with more humor!). Not that I particularly blame Knight Rider, because it’s such a common meme. So, for the record, infrared cameras cannot see through walls. These cameras, like night vision goggles, pick up lower wavelength electromagnetic signals that we sense as heat. But the insulated walls of buildings are designed to block heat from escaping, essentially forming a…well, a wall between the camera and person in the building. Luckily, there are many excellent real ways for KITT to see through walls.
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