Wednesday, 31 December 2014

Ride the Wormhole: The Ridiculously Hard way to Cheat on your New Year’s Resolutions

Well New Year’s Eve is once again upon us and as we look back at the 12 months we have just spent hurtling around the Sun it is pretty likely that a lot of us will end up feeling like failures. Each year starts with such promise. We make resolutions to lose weight, run a marathon, learn French once and for all; unfortunately, most of us fall short. But don’t panic yet, you have until the clock strikes twelve to accomplish what you set out to and avoid the dreaded stink of a botched resolution! Depending what time you read this you might have 8, 10, or even 14 hours to pull of the resolution Hail Mary. Luckily, there is a trick of physics that might help buy you some more time.

All we need is a wormhole. Sure, you’re probably busy getting ready for some party tonight and the odds of finding the perfect wormhole are appallingly slim, but Einstein and one of his physics buddies named Nathan Rosen have told us that wormholes are consistent with the known laws of the Universe. So to quote the fictional and festively named Lloyd Christmas “You’re telling me there’s a chance…”

Wormholes, or Einstein-Rosen Bridges if you’re the name dropping type, are the result of chance alignments between ridiculously heavy objects in space. To understand why they allow for time travel, you need to accept that time is just another dimension of space. That’s right, you can move forwards and backwards, left and right, up and down, and through time. If you don’t believe me, go back and read our article on time dilation. A wormhole is just a link between two points in space caused by the warping effect that mass has on space-time.

Imagine space-time as a bed sheet folded in half with a space between the top and bottom layer so it forms a sideways U shape. That is the curved universe we live in. Now imagine a weight placed on the top layer of the sheet that pushes down towards the bottom layer. This is what heavy objects actually do to the space around them. Now imagine another weight placed on the bottom layer of the sheet so that it pushes up towards the top. If the two dents in our astronomical bed sheet touch one another, we have created a link between two points that didn’t exist before. That is our wormhole.

Theoretically if you could travel through that wormhole you could outrace a beam of light traveling between the same two points, but moving through regular space. Since time is just another dimension of space, when you get through the wormhole, you might just find you have traveled back in time. If you’re ridiculously lucky, you might even find yourself on December 31, 2013 with a fresh crack at your resolutions.

The problem with our plan, aside from the probabilities involved, is that wormholes are thought to be very unstable. They might exist for only a tiny fraction of a second before collapsing in on themselves because of the huge amounts of gravity involved. What we need to really harness them is what physicists call “exotic matter.”

Exotic matter is any particle with traits that allow it to blow your mind. The type of exotic matter we need is the kind with negative mass. It might seem crazy, but it might actually exist. Scientists at the Large Hadron Collider have already begun finding exotic particles, and negative mass particles are on their most-wanted list. A particle with negative mass is a crazy thing to think about. These particles would be repelled by gravity and if you hit one with a hammer it would take off towards the hammer! If we, or a super advanced civilization, could figure out how to harness these particles we could use them to cancel out some of that wormhole mass and keep the bridge open long enough to move through.

Unfortunately, this doesn’t do much to help us with this year’s resolutions. Unless one of those extra-terrestrial traps you’ve been baiting with Reese’s Pieces all year gets sprung in the next few hours, you might have to actually work to accomplish your next set of life goals.

Friday, 26 December 2014

Sketchy Fact #73: Tall Trees

The tallest Christmas tree ever recorded was a 221 foot (67 meter) tall Douglas Fir cut down and displayed in Seattle, Washington in 1950. The tallest potential Christmas tree in the world is "Hyperion" a 379 foot tall (115 meter) coast redwood... It's illegal to cut it down, though, so you would have to have a Christmas camp-out.

Wednesday, 24 December 2014

The Immaculate Conception: How to have a baby without getting busy

Special thanks to Denis "the Menace" Lanno for suggesting this festive topic.

Of all the Christmas stories calling out for a scientific explanation, the virgin birth stands in a league of its own. While science and religion so often choose to avoid each other completely the immaculate conception all but demands a closer look. Whether or not you believe that a couple thousand years ago a middle eastern woman got pregnant while still a virgin, the question of whether or not such a thing is possible is undeniably interesting. There may even be an off chance that this sort of thing is fairly common. In a recent self-report study, 1% of US women reported having children without ever having had sex. We wouldn’t want to dismiss their claims without giving the subject a fair, open-minded glance. So come along with us on this magical Christmas Eve as we dig into the science of unilateral reproduction!

Virgin birth is a biological problem that involves things we actually know a good amount about. In normal reproduction an egg is produced by a women which contains copies of half of her 46 chromosomes. When that egg and its 23 chromosomes meet up with a sperm, containing 23 chromosomes from the man who produced it, the result is a “zygote” which eventually divides into a cluster of cells called and embryo and on into a baby somewhere down the line. If we are looking to explain a virgin birth we somehow need to find a way to get that second set of chromosomes into an egg and give it the ability to divide using only the resources available in a normal woman’s body. It’s like that part of Apollo 13 where they have to fix the air filter with duct tape and coffee filters.

When we take a look at the tools we have available there is one fairly important thing that is missing: A Y-chromosome. As it turns out, the biggest problem with the story the Bible provides is that Mary (a woman… presumably) gives birth to Jesus (a male). The thing is, chromosomes come in pairs. The pair of chromosomes that determine gender in humans can be either X or Y. Women have two X chromosomes (XX) and men have one of each (XY). As you can see, Mary doesn’t have a spare Y chromosome to provide her baby with.

If Mary were a reptile, we might have something to work with. In fact, asexual reproduction has actually in observed in boa constrictors, komodo dragons, a few birds, and a couple other kinds of vertebrates. The process basically amounts to cloning since the genetic material involved is all identical to what is found in the mother. The cool thing about reptiles is that females are defined by their ZW sex chromosomes while males have a ZZ combination. That means that it is actually theoretically possible for a female snake to give birth to male offspring without mating, by giving an egg 2 Z chromosomes. What makes the whole situation mind-blowing is that, in practice, when scientists first observed this process in nature, all the offspring tested had 2 W chromosomes, meaning that they were an entirely new gender! This process is called parthenogenesis and it is useful when an animal is cut off from potential mates.

That doesn’t really help us explain Jesus, though. Fortunately, we are left with one pretty cool, albeit slightly complicated, possibility. To understand it we need to appreciate why parthenogenesis doesn’t happen in mammals. To put things very simply, the genes that a growing mammalian egg cell is provided with do not allow it to develop past a certain point. This is called “genetic imprinting” and you can think of it as a sort of cellular traffic signal. Under normal conditions, eggs cells grown in female mammals contain a “stop” code that prevents them from growing into embryos on their own and it is only when a male sperm cell containing the green-light “go” code arrives that things can get underway.

Research from Japan and South Korea has shown that a good part of the stop and go process is controlled by two genes called Igf2 and H19. In experiments with mouse embryos, researchers determined that the H19 (stop) gene normally blocks the growth-stimulating Igf2 (go) gene in egg cells. When scientists, who were very keen to play god in the most literal sense, mutated the H19 gene, deleting 13,000 of its bases, they managed to produce 26 viable, unfertilized eggs (out of around 600 eggs they started with) that led to 10 live mouse babies. Only one of those pups survived to adulthood, but to back up the Christmas origin story we only really need one anyway.

So what are we left with? Is the Immaculate Conception a scientific possibility? The short answer is maybe.. but not exactly as written in the Bible. First, we need to assume that human reproduction is similar enough to mouse reproduction that we have any evidence at all to go on. Next it would require a genetic mutation so precise and so unlikely that the scientific method has never in modern history found evidence for it ever happening naturally. Then, and only then, might we concede that after having produced an egg with a crippling mutation on its H19 gene, and having suffered no other mutations that would damage it beyond repair, that a woman named Mary might have given birth to baby without having sex… but we still don’t know where she would have gotten that Y chromosome.

Friday, 19 December 2014

Sketchy Fact #72: Santa's Sherry

In the UK children leave Santa a glass of sherry. Assuming Santa weighs around 250 lbs, he is too drunk to drive his sleigh after the 6th house. Good thing he has DD elves.

Wednesday, 17 December 2014

Frosty the Slime Mold: How to Create a Living Snowman

I was a pretty dumb kid. I remember once I put orange juice in my morning cereal when we were out of milk and watched in horror as my mini-wheats swelled to 4 times their normal size and took on a taste that can only be described as gut-wrenching. But dumb as I was there was one Christmas story that bugged be for it’s implausibility: Frosty the Snowman. You all know how it goes. A bunch of kids make a snowman, wish him to life, and have wacky adventures all over town. Anyone who has ever made a snowman knows that the wacky adventures are in the building of the thing. If you’re expecting to build a new friend that you can melt away with a hair dryer when he gets annoying, you are in for a harsh reality check.

As I’ve grown older, however, and learned about the supremely weird things that can happen in nature, I’ve begun to rethink my harsh critique. As it turns out, under just the right set of circumstances (involving tonnes of unrealistic assumptions and the invention of a whole new “maybe it could exist” species) you might just be able to create a passably intelligent snowman.

Okay so here we are in a field near a forest. There is a fresh blanket of snow on the ground and we’ve set to work making our snowman. Unbeknownst to us, however, those aren’t just plain old ice crystals we’re balling up, they are loaded with amoebas! We pop in a corn cob pipe, a button nose, throw on a top hat and are amazed when our new frozen friend begins moving around the field on an apparent unspoken mission… He may not be singing or dancing but something weird is going on. Is it magic? Not quite.

It turns out that some amoeba’s can play a pretty neat trick. When food is scarce or conditions are bad these single celled organisms can come together and create a sort of slug. That slug can slide around in search of food and even displays an intelligence that goes beyond what is possible for a single amoeba. Scientists call these slugs slime molds and they have shown that, when working together, amoeba colonies can solve mazes in search of food. One imaginative researcher even created an experiment where the amoebas designed a railway system for the United Kingdom that turned out to be more efficient than the one humans created. I am not making this up.

For this to even be partway plausible we need to imagine a slime mold that is also an extremophile. Extremophiles are organisms that make our assumptions about life look just plain silly. As the name suggests, extremophiles love extreme environments. They live in boiling geyser water in Yellowstone National Park and can survive and thrive at the bottom of the ocean where temperatures are incredibly low and pressures are incredibly high. It isn’t much of a stretch then to imagine a slime mold extremophile that thrives in frozen water. Maybe it could even use the structure of the crystals to strengthen the structure of the multicellular organism it forms when individual amoebas come together. Maybe when you form the snow it lives in into balls, that structure is at its strongest and becomes the perfect skeleton to do some exploring with.

Unfortunately even in our wildest imagination, a talking slime mold is going a little too far. Frosty would likely be a lot less chatty and rely on sign language a lot more. As for the singing and dancing… Well, music might actually help our amoeboid Frosty become a little more lively. Research has shown that exposing microbes to music actually improves their ability to do work. One German sewage plant actually makes a point of playing Mozart through its pipes to help bacteria break down waste faster.

Christmas is a time for improbable things, and we live in an improbable world. Santa delivers presents to every house in the world. Bioluminescent Reindeer fly through the sky. Who's to say in this crazy world of giant squid and ipads that a slime mold couldn’t evolve a way to warm the cockles of your heart. Here’s to you Frosty, and all your frozen, slimey, amoeba buddies.

Friday, 12 December 2014

Sketchy Fact #71: Oh Deer...

Deer antlers are one of the fastest growing tissues in the animal kingdom. They can grow as much as 1/2 an inch per day, assuming Santa gives his crew a balanced diet.

Wednesday, 10 December 2014

Turkey Power: What does it take to cook a Christmas Turkey?

Even for the most organized of us, the holiday season is a hectic one. Your time is split between getting your shopping done, visiting all your friends and family, and upping the festive factor of your house, to the point where Clark Griswold himself would be giving you a solid high five. But even within this chaotic holiday season, there’s one thing that many people look forward to – a perfectly cooked Christmas Turkey.

So, what’s the secret to the perfect Christmas Turkey? Some would say freshness, others may argue that it's seasoning. But at Sketchy Science,  we believe the key is in perfecting the Rube Goldberg-esque process by which energy is transferred between system boundaries countless times, until it reaches your cooking device, manifests itself as kinetic energy at the molecular level, that eventually enables material phase changes and the high speed molecular dance, which breaks and re-forms chemical bonds. How else would you ensure your turkey is lip-smackingly juicy and delicious?

Of course, I’m talking about cooking the turkey, and when you think about it, the molecular dance is a result of turning on your oven to 350 degrees Fahrenheit and pumping your bird full of heat energy for three to four hours (or until golden brown). But have you ever thought about how much energy it takes, where it comes from, or what else you could be doing with that turkey-cooking energy?

Probably not, and that’s why we’ve done the thinking for you.

Let’s begin with the basics. Loosely speaking, energy is the ability to do work, and we measure it in units called Joules (J). It comes in many shapes and sizes, and can be converted from one form to another. For example, the sun emits solar energy, which plants convert into chemical energy through the process of photosynthesis. When you eat the plant, your body metabolizes the sugar to power your muscles. If you then use your muscles to lift some weights over your head, you’re converting the chemical energy into gravitational potential energy. If you happen to give up on that last rep and drop the barbell, the falling weight has kinetic energy. Even the agonizing scream you may let out when the weight falls on your foot is a form of sound energy. But what kind of energy does it take to cook a turkey? Let’s take a closer look at our friend, heat energy.

There’s a simple formula to figure out how much energy it takes to heat a material to a certain temperature:

Q = mc(T2-T1),

where Q is the amount of energy in joules, T1 is the starting temperature of the material, T2 is the final temperature of the material, m is the mass of the material, and c is something called the specific heat capacity. Specific heat capacity is a property of the material in question; it tells us the energy required to raise the temperature of one gram of material by one degree Celsius. With this handy formula, we can figure out how much energy it takes to cook a turkey from room temperature (about 23 degrees Celsius) to the safe consumption temperature of 74 degrees Celsius. In case you’re wondering, the specific heat capacity of turkey is 2.81 J/goC (and yes, someone put in the effort to figure that out empirically.

Assuming an average bird mass of 12 lbs., after crunching all the numbers, we get about 780,000 joules, or approximately 800 kilojoules (kJ). Note that we don’t take the inefficiencies of the oven into account; in reality the energy usage would be a bit more. How much is 800 kJ of energy, you ask? Let’s take a look at what we can do with it.

Since energy is such a fundamental concept, we can compare its quantities across many domains. For example, Calories are a measure of food energy, and one Calorie has energy equivalent to 4.184 kJ. So, the 800 kJ in question is about the same as 191 Calories. In other words, a handful of M&M’s has enough food energy to cook a Christmas Turkey.

Electrical engineers measure the capacity of a battery in units called watt-hours. But since all a battery really does is store energy, we can always convert it back to our old friend, the joule. Knowing this, 800 kJ is enough energy to charge the 5.45 watt-hour battery of your iPhone 540 times. On the flip side, when we apply a similar analysis to the battery of a Tesla Model S, we see that the 800 kJ is only enough energy to drive the Tesla 1.3 km. This gives you an appreciation of how much energy is consumed to move a car around.

What if we were to scale the problem up a bit? In Canada, we eat approximately 3.9 million turkeys at Christmas time each year. Multiply that by the 800 kJ of energy used to cook each turkey, and we arrive at 3.12 terajoules (TJ). To give you a sense of scale, 1TJ is 1,000,000,000 kJ. This is about the same amount of energy that is released in a 1 kiloton (kt) explosion. One kiloton, as you would expect, is the amount of explosive energy released when you detonate 1000 tonne of TNT. If we gave all of that explosive energy to Santa, he would have the equivalent of 100 Davey Crocket missiles - perfect for “tactical defence” of the North Pole.

Let’s scale it up one more time.  During Christmas every year, Canada, the USA, and the UK consume a combined 36 million turkeys. At 800 kJ per turkey, that is a whopping 28.8 TJ of energy. To put this into perspective, let’s say we wanted to launch a projectile from Earth. We can calculate how much energy we can supply to it using the expression for kinetic energy:

Ek = (½)mv2,

where Ek is the amount of energy in joules, m is the mass of the object in kg, and v is the velocity of the object in m/s. Now let’s say, hypothetically of course, that our projectile is the International Space Station (m = 419,000 kg), and we give it enough energy to achieve the escape velocity of the Earth (v = 11,200 m/s).  Plugging in all the numbers, we arrive at approximately 27 TJ, which is about the same amount of energy used to cook turkeys in just three countries every Christmas.

Though to be fair, we didn’t take into account the air resistance, which would also require additional energy to overcome.  But, why try to go through the air when you can just get rid of it all together?  If we were able to build a perfectly sealed column 100 m by 100 m wide, and tall enough to reach the edge of our atmosphere (about 100 km), we could evacuate all of the air and never have to worry about air resistance ever again!  Using a few standard 10 HP air pumps that can move 60 cubic feet of air per minute, we could get rid of the air with an energy cost of about 26 TJ, which is slightly less than the global turkey energy consumption per year.  

What does this all mean? The amount of energy we use during just two Christmases to cook festive turkeys could hypothetically remove the air from a sufficiently sized tube, and shoot the ISS from a cannon with enough speed to escape the gravitational pull of the planet.

Of course, there are other types of energy we didn’t discuss. The sun uses a process known as thermonuclear fusion to keep itself shining and shower us with energy goodness. In fact, the Earth receives about 122,000 TJ of energy from the sun every second. That’s enough energy to cook the world’s Christmas turkey dinners for 4300 years!

So, the next time you are stuffing your face with Christmas turkey, take a step back and think about all the chain of energy processes that took your bird from raw to golden brown and delicious.  Perhaps do a few of your own back-of-the-envelope calculations and ponder upon the other things on which you could be spending your energy.   

You may just be surprised.

Friday, 5 December 2014

Sketchy Fact #70: Mint-Condition Memory

Research has shown that the flavour and even just the smell of mint (abundant in candy canes and Christmasy tea) can boost memory and improve overall brain function. Maybe that's why we all remember our childhood holidays so well...

Wednesday, 3 December 2014

Cookie Chemistry: Using Science to Bribe Santa

As Santa can attest to, nothing quite beats the mouth-watering aroma, delightful texture, and scrumptious taste of a plate of perfectly baked cookies. Since the early 1930's Santa has been munching down on plates of cookies left out by children, desperate to make up for a year of sub-par behaviour. If the man in red merely took a nibble of one cookie from every plate left out for him each year, he would eat over 336 million cookies in one night. Unfortunately for Santa, those cookies probably aren’t  always the picture of cookie perfection.

It is notoriously difficult to bake a perfect cookie. First of all, not everyone’s definition of "perfect" is the same. Some prefer a more light and cakey consistency. For others, the perfect cookie is flat and crisp around the edges with a gooey centre. Still others find that perfect means the treat is chewy throughout. Second, most people have no idea why one recipe will result in a chocolate chip cookie that is crisp and flat while another, seemingly identical, recipe will result in cookies that are dense and chewy. It should come as no surprise that science is to blame for your failures in baking.There are a myriad of variations on the traditional chocolate chip recipe, but for time’s sake, we’ve narrowed it down into three main cookie types: flat, cakey, and chewy.

Flat Cookies:

These cookies are flat with crisp edges and a soft, gooey centre. Surprisingly, they are a result of increasing the amount of leavening agents in the dough. Using a mixture of leavening agents, usually baking soda and baking powder, will increase the spread of the cookies. Baking soda encourages browning by neutralizing the acidity in the brown sugar, vanilla, and butter, leading to crispy edges. Baking powder, which is a mix of baking soda and an acid, reacts when introduced to a liquid (i.e. melting butter) giving off carbon dioxide and producing little pockets of air throughout the dough, causing it to rise in the oven. The overload of the two leavening agents causes larger and less stable air pockets in the dough which will collapse as the cookies cool, leaving you with a delectably soft and gooey centre.

Cakey Cookies:

These cookies are puffy and soft. This texture is achieved by using only baking powder as the leavening agent in the dough.  While baking soda relies on the acidity of other ingredients in the cookie to form its reaction, baking powder already contains the acid (usually calcium phosphate) and reacts when introduced to a liquid (you can see this reaction by adding a drop of water to baking soda). Melting butter and sugar in the baking cookie activate the baking powder, releasing carbon dioxide. The result is a mess of small air pockets in the cookie that push upward and cool into a stable dome.

Chewy Cookies:

These cookies are… well… chewy. The texture is a result of two changes to your traditional chocolate chip cookie recipe: melted butter and bread flour. Normally, recipes call for softened butter (solid butter at room temperature). Melting the butter instead causes the milk fats and water to separate. This will be useful when you combine the wet ingredients with the bread flour. The protein content of bread flour is higher than that of regular, all purpose flour and that leads to a tougher end product. That is why bread flour is used to bake chewy baguettes. Those extra proteins in the bread flour combine with the water in the melted butter to form gluten, which is chewy! The bread flour will also absorb more moisture, resulting in moister cookies.

Believe it or not, there are even more variations to be had on the traditional chocolate chip cookie. Check out this blog to see how other ingredients and baking techniques affect cookies.