Apr. 15, 2012
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Imagine the World if just 1% of the 7,000,000,000 people did the same thing?
Yes, what a great story! We need more people like this guy.
Apr. 15, 2012
George Musser in Scientific American:
Vasiliev theory (for sake of a pithy name, physicists drop Fradkin’s name) takes to extremes the basic idea of modern physics: that the world around us consists of fields—the electrical and magnetic fields and a handful of others that represent the known forces of nature and types of matter. Vasiliev theory posits an infinite number of fields. They come in progressively more complicated varieties described by the quantum-mechanical property of spin.
Spin is perhaps best thought of as the degree of rotational symmetry. The electromagnetic field along with its associated particle, the photon, has spin-1. If you rotate it 360 degrees, it looks the same as before. The gravitational field along with its associated particle, the graviton, has spin-2: you need to rotate it only 180 degrees. The known particles of matter, such as the electron, have spin-1/2: you need to rotate them 720 degrees before they return to their original appearance—a counterintuititive feature that turns out to explain why these particles resist bunching, giving matter its integrity. The Higgs field has spin-0 and looks the same no matter how you rotate it.
In Vasiliev theory, there are also spin-5/2, spin-3, spin-7/2, spin-4, all the way up. Physicists used to assume that was impossible. These higher-spin fields, being more symmetrical, would imply new laws of nature analogous to the conservation of energy, and no two objects could ever interact without breaking one of those laws. The workings of nature would seize up like an overregulated economy. At first glance, string theory, the leading candidate for a fully unified theory of nature, runs afoul of this principle. Like a plucked guitar string, an elementary quantum string has an infinity of higher harmonics, which correspond to higher-spin fields. But those harmonics come with an energy cost, which keeps them inert.
Vasiliev and Frakin showed that the above reasoning applies only when gravity is insignificant and spacetime is not curved. In curved spacetimes, higher-spin fields can exist after all. Maybe overregulation isn’t such a bogeyman after all.
Posted by Robin Varghese at 03:56 PM | Permalink
If 1980s movies are to be believed, Siberia is a frozen hellhole suitable only for bears, Russian prisoners and inept American spies. It's nothing but frozen tundra and despair until you get to Alaskan crab waters and reality TV crews. But it was once worse. Way, way worse. About 250 million years ago, Mother Earth experienced a truly epic case of irritable bowel syndrome under what is now Russia's frozen armpit.
Near what was to be the end of the Permian period, Earth was ruled by pre-dinosaur reptiles and giant freaking bugs before Siberia erupted. Not a volcano in Siberia; Siberia itself. Scientists believe a mantle plume, aka "hotter lava," rose up and hit Siberia and, in strictly scientific terms, blew it right the hell up. A piece of earth the size of western Europe exploded, possibly causing an event called the Great Dying.
It was a continent-sized game of "the floor is lava."
While the simple explosion of a continent was probably enough to screw up everything on its own, the Siberian traps had more tricks up their volatile sleeves. They were located next to large coal fields, causing the release of massive amounts of methane and carbon dioxide. This could have triggered a clathrate gun reaction, which in turn would have led to an anoxic event that would have poisoned everything that wasn't exploded or suffocated/baked by the previous two apocalypses that just happened. In other words, it was the perfect storm of "screw you, everything."
Ninety percent of all life on earth was wiped out, and land life took 30 million years to recover.
And eventually evolved into a perfect form.
The expanse of Siberia was "paved over" in basaltic lava, forming the traps, which get their name from the Swedish word for stairs. Here is what a continent-sized apocalypse looks like:
Holy God, it's ... OK, that's actually kinda neat looking.
But this, well this is just ... alright, that's awfully pretty.
OK, so apparently after a quarter of a billion years, even hell is kind of nice to look at.
Don't let the pretty pictures fool you -- the chain reaction started by the Siberian traps spent a million years murdering most of the life on Earth. And the best part? It could happen again.
The cetaceans (whales and dolphins) are some of the most beloved and respected animals in the world. Whales are the gentle giants of the sea, while dolphins are the fun-loving clowns who show up in a lot of female tattoos, despite the fact that they maybe also are serial killers.
Now we all know that these regal creatures are mammals, so they're not as related to fish as you might otherwise think. But it would be safe to assume that their closest relatives would have to be 1) aquatic and 2) not huge lazy fatasses, right?
Closest Living Relatives: Hippopotamuses
We really hope this isn't some sort of hipporgy.
Well, that first assumption was semi-right, but we were way off the mark on that "huge lazy fatass" part. Just don't tell them that to their faces.
According to recent evidence, whales and hippos probably share the same great-great-great- (ad infinitum) grandpappy that lived about 50 million years ago. This ancestor split into two groups: the cetaceans and the anthracotheres. Believe it or not, whales and dolphins used to walk on land and were semi-aquatic, like crocodiles and otters. Here's a bad drawing of an Ambulocetus, an early whale ancestor:
It turns out the distant past was kind of a huge nerd.
Now, here's an early anthracothere:
Well, Danny DeVito makes a lot more evolutionary sense now.
It's sort of like a hippo that tried one of those new fad diets and got even dumber as a result of the lack of nutrients. Anyway, over time the cetaceans became more and more aquatic, until they eventually abandoned the land altogether. Meanwhile, the anthracotheres died out (presumably slowly and lazily), leaving only one descendant: the hippo.
In fact, scientists have argued that dolphins and whales should be combined into the order Artiodactyla, which contains not only hippos, but also deer, camels, cows, pigs and giraffes. Yet, if you came across a whale humping a camel, you'd think it was weird.
We humans have a very odd relationship with bears. On the one hand, we put our kids to bed with a stuffed one every night; on the other hand, we'd shit our pants if we ever encountered a real one out in the wild. Take that big guy standing up there, for example: Have you ever seen another photo that simultaneously says "Hug me" and "I want to gnaw on your sweet, sweet face-meat"?
So you're probably thinking that, since bears are somehow concurrently cute and badass, their closest relatives must also be equal parts both, right? Well, Mother Nature doesn't always work that way.
Closest Living Relatives: Pinnipeds (Seals, Sea Lions, Walruses)
Any bear smiling like that just devoured a hiker.
Actually, it looks like bears' closest living relatives have all the cute, but got severely shafted on the badass. The pinniped's location in the evolutionary tree has always been a little tricky, but genetic evidence revealed that pinnipeds are closely related to bea....
"But Cracked," you say, "seals don't even have freaking feet. You don't have to be a biologist to call bullshit here."
True, but have you ever taken a close look at a seal's flipper? We're guessing that's a no, so here's a pic:
"Down low -- TOO SLOW!"
Now here's a bear's paw:
The seal's flipper is flatter, and the bear's claws are longer (raise your hand if you knew that seals even had claws), but other than that, people who are way smarter than us yet spend a whole lot more of their time staring at animals' feet have found that they're very similar. Both have non-retractable claws, both have five claws on each foot, both have the same basic bone structure and both are plantigrade (meaning that both the heel and toe touch the ground).
In fact, the fossil record indicates that the pinnipeds probably arose from a bearlike ancestor called Puijila, which was a powerful predator that could run on all fours like a bear but also had webbed toes, allowing it to hunt in the water. Today, pinnipeds are rarely found in freshwater and, needless to say, they gave up on all that "running" bullshit long ago.
Perhaps one day, if we couch potato hard enough, we can reunite with our wiser brethren.
Just think: If Puijila had taken a different turn on Evolutionary Road, we might have bears that could outrun, outclimb and outswim you before using their cuddliness to lure you straight into their pointy bits.
The peaceful equids (horses, donkeys and zebras) were enslaved by the human race to do our bidding -- sorry, domesticated -- several thousand years ago, and since that time they've been an invaluable resource for transportation, agriculture, warfare, companionship and sometimes-horrifying entertainment.
So they're probably closely related to cows, sheep or some other animal you'd sing about living on an elderly Scottish man's farm, right?
Closest Living Relatives: Rhinos
They're related to the suborder Ceratomorpha, which sounds like something from the Power Rangers and includes the rhinoceros and the tapir. Now, assuming you haven't visited a zoo recently, you're probably thinking, "OK, so what the shit is a tapir?"
The shit is actually off screen.
So a tapir sort of looks like a rhino who's lost all his cool rhino stuff (i.e., the armor and the face full of death-by-impalement) and is feeling pretty bitter about it. Either that, or he's the only animal in nature that's permanently constipated. Anyway, if you go far enough back, you see how similar all of these animals are. For instance, rhinos have three toes that they walk on:
Just like that kid at school who grew up real close to the power plant.
... and so did horses, once. But two of their toes evolved away with time, leaving just the one huge middle toe and toenail that we now refer to as a hoof.
There's supposed to be a unicorn in there somewhere.
That's right -- Mother Nature engineered horses to flip us a perpetual bird with each foot. Which seems somewhat justified considering all the shit we've made them do over the years, don't you think?
We know what you're probably thinking right about now. "Come on, Cracked," you say in your thick Scottish brogue (because we like to imagine that all our readers sound like Sean Connery). "Everyone knows hyenas are some kind of lopsided dogs. You can't surprise us by telling us that once you dig down past the inch-thick coat of ugly, they're practically man's best friend."
But before you run out to the nearest rescue shelter to see if there are any hyena pups available, there's something we need to tell you.
Closest Living Relatives: Mongooses
Dictionary be damned. The plural of "mongoose" will always be "mongeese" to us.
Wait, how could something that looks like somebody mixed equal parts broken stepladder, mange and hate be closely related to these cute and cuddly little ferret-things? It might be easier to swallow when you remember that mongooses like to murder the shit out of snakes just because why the fuck not? but, but ... CUTE! And hyenas tried to kill Baby Simba! Baby Simba! How could this be right?
Well, carnivorous mammals (the order Carnivora) are divided into two suborders: the doglike carnivores (Caniformia) and the catlike carnivores (Feliformia). You might think by looking at them that hyenas belong in the "doglike carnivore" class, but they actually belong in the suborder Feliformia and share a close branch with the mongoose family, which also includes the meerkat (e.g., Timon from The Lion King). That's right, the lovable little guy who convinces Simba to forget about all his worries is the long-lost cousin of the animals who helped kill his dad. Et tu, Timon?
Above: The "Loose Change" of the lion world.
And yes, that also means hyenas are more closely related to cats than to dogs. So be sure to pick up a litter box when you go get yourself that new guard hyena.
We've talked about sea squirts (tunicates) before. They're the poor, unfortunate souls that swim around like little tadpoles, happy as any spermlike creature can be expected to be, when all of a sudden their evolutionary programming takes over and they attach themselves to the sea floor, devour their own brains, lose their ability to swim and filter feed for the rest of their boring, miserable existence.
So which animals do you think are these doomed little guys' closest living relatives?
Sponges? Corals? Worms? Nope.
Closest Living Relatives: Vertebrates Like You
Go Team Spine!
That's right, say hello to your Cousin Squirt.
Vertebrates (you, other mammals, birds, fishes, reptiles and amphibians) are the closest evolutionary cousins of the sea squirt. In fact, scientists believe that the sea squirts (especially in their larval form) may resemble the original ancestor of all vertebrate life on earth. In other words, your earliest ancestors may have looked something like this:
Jim Williams, Southwest Tennessee Community College
If we're looking at that right, our ancestors were particularly well-hung.
So consider this: Instead of inventing new technology, creating fabulous works of art and writing dick jokes on the Internet, we could have parked our asses on the sea floor and devoured our own brains.
This is an astonishing story, and has a strange similarity to our View From Your Window contest. A young Indian boy fell asleep on a train journey, lost his brother, took another train to find him and became completely lost at five on the streets of Calcutta. He was eventually taken into an orphanage, but eventually used Google Earth to trace his fateful train journey as a child, to get images that might bring back memories of the past, and to find his mother. He couldn't remember the name of his town, or his family. But images worked:
"It was just like being Superman. You are able to go over and take a photo mentally and ask, 'Does this match?' And when you say, 'No', you keep on going and going and going ... When I found it, I zoomed down and bang, it just came up. I navigated it all the way from the waterfall where I used to play."
He and his mother were numb when they met each other again. His brother? His body had been found on the railroad tracks.