We know how the universe will end. Sort of.

Of all the topics in modern science, none is more mysterious than exactly what the heck the universe actually IS.  How big is it?  What’s outside of it?  What’s the point?

I would love for any morsel of new insight into the universe to occur within my lifetime, but hey, it makes for great sci-fi in the meantime.  Regardless, we actually know more about the universe than you might initially think.  Specifically, we know what’s going to happen waaaaaaay down the line at the end of the universe, provided that nothing else catastrophic gets in the way.  You can convey this end -of-the-universe concept by using the term “heat death of the universe.”  The scariest part?  Every second the universe exists is a second we’re hurtling towards its eventual death.

http://abyss.uoregon.edu/~js/ast123/lectures/lec26.html

The heat death of the universe sounds complicated but it’s really a super simple idea.  We’ve looked in previous posts at how things tend to get messier over time – clothes and books in your bedroom, smell molecules in house, and food coloring in a glass of water.  All of these things eventually find equilibrium by being evenly spread out over their medium.  We also know that heat does this – if you open a hot oven, the heat trapped in the air will slowly rise and disperse throughout the room.  As it spreads out more and more, it transfers heat to the surrounding environment because heat can only flow from hotter areas to colder areas.  Without us putting any work into it, anything that’s hot will automatically try to move out towards anything nearby that’s colder, with the end result being that if you open a hot oven in your kitchen, your entire kitchen will eventually reach the same temperature in every little nook and cranny.  So it’s kind of obvious that heat dissipates, right? Well if we consider this heat to be increasing the “messiness” of whatever room it’s in, we can see that it’s actually following the Second Law of Thermodynamics quite nicely.

http://www.creationsciencetoday.com/_images/02-HeatDeathGraph-lrg.jpg

 

Second Law of Thermodynamics: In any process the entropy will either increase or remain the same.

In other words, if your room is messy, it’s high in entropy.  Any energy you use to straighten it up also releases more heat, which makes the room messier because the once-concentrated heat from your body is now being spread out over a much larger area.  So even when you’re cleaning a room to reduce its entropy, the end result is always, always, always, that you’ve increased the entropy of the universe as a whole.

This same rule applies to all the stars in the universe.  Stars are essentially “burning elements like hydrogen and helium” and produce enormous amounts of heat as a result.  But, of course, their supply is finite – any star that runs out of materials to burn will eventually collapse in on itself due to its very high mass and gravity.  We could get into the life cycle of stars, but we’ll save it for another time.  Suffice it to say that even star, including our own sun, operates under a time limit – when it runs out of stuff to burn, it’ll die.

But think about all the heat that’s being released from the sun!  Huge amounts of heat that one second reside entirely within the sun are being dispersed all through the Milky Way and beyond, searching for colder areas.  In other words, the entropy of the universe is also being increased constantly by stars.  Now try to imagine a time when all the stars and energy/heat sources in the universe have expended their energy.  Slowly, heat will disperse evenly through the universe until it is even distributed, just like food coloring in a glass of water.

Now, heat energy is essentially a wasteful by-product of doing work.  When you go for a bike ride, you get hot and sweaty because your muscles are expending energy to move, and some of this energy is lost in the form of heat (since no process can ever be 100% efficient, all “burning” reactions result in some heat loss) This heat that’s lost to the surrounding area can’t be recaptured – what was once organized energy in your muscles is now permanently useless to humans as a fuel source.  To simplify, let’s say that all processes in the universe are 90% effective, meaning they give off 10% of their energy as useless heat.  After some unknown time period, we have less and less available energy to work with, and more and more of it is becoming heat energy that disperses.

Once all the energy in the universe is at maximum entropy (used up and disorganized), then there can be no further work or transfer of energy.  In short, that means no life at all.

Of course, this is merely a theory, and the amount of time before this actually occurs is, for all intents and purposes, infinitely far in the future.  You might also be interested in checking out other theories, such as “Big Freeze,” “Big Crunch,” and “Big Rip.”  In all cases, however, we are pretty certain that the universe will end – a prospect that is made all the more fascinating and terrifying by our relative ignorance about just what exactly this universe is all about.

“Cholesterol is not a nutrient of concern for overconsumption.”

Look, nobody’s perfect, especially in the science world.  Researchers all over the world probably make a handful of mistakes for every one thing they get right – the world is just such a complicated place.  When we do scientific research, we’re only testing out theories — and the only way to arrive at the correct answer is to systematically eliminate as many of the false possibilities as you can.

Case in point, The Office of Disease Prevention and Health Promotion recently decided that cholesterol was not longer “a nutrient of concern,” which might be a slap in the face for anyone who has ever had a lipid panel, talked to their doctor about cholesterol, or avoided eating shrimp and eggs because of their high cholesterol content.  The United State’s stance on various dietary choices has continually bounced around over the past 60 years, never settling on any one set of guidelines.  One good argument here is that not all individuals should be eating the same diet.  If you listened to pop culture a few decades ago, you’d have thrown away the butter and relied on Crisco or shortening, which may have contained trans-fats and thus were generally deemed to be harmful to your health.  Cholesterol, salt, and fat have all been through that ringer, but none (almost none of the peer-reviewed, reproducible ones, anyway) of the studies we’ve done have really produced solid scientific evidence that we should avoid them at all costs.  So the nation picked up Crisco.  Then it picked up low-sodium snacks.  Then it picked up fat-free heavy cream (which shouldn’t exist without disturbing the space-time continuum, in my book).

And now we come to today, when cholesterol is no longer a threat.  Fear not eating eggs and shrimp and all kinds of meat products!  The interesting part about this change to the guidelines, though, is that we already knew this.  Countless studies have not only shown that dietary cholesterol doesn’t cause any health problems (and it certainly doesn’t get stuck into your bloodstream and case plaque), but it’s also recognized that 90% of the cholesterol in the human body is produced internally, that is, by your organs.  Clearly, cholesterol or one of its precursors/products is needed in the body in some way, or we wouldn’t waste resources making it.  Whatever the reason for it, we’ve known for quite some time that if you give Group A no cholesterol and you give Group B 300% of the recommended daily value of cholesterol, over an arbitrary time period their blood cholesterol levels show no correlation with how they’re eating.  And even though we’ve known this and had the evidence for some years, we’re only just now getting updated guidelines.

Hopefully this makes you wonder about what else we as a civilization don’t know about ourselves.  Until recently we didn’t know that cholesterol wasn’t bad for you.  Until recently we thought margarine and Crisco were healthier alternatives to butter, because we thought that butter caused heart disease.  One day in the future we’ll come to realize that something else we thought was harmful might not actually be, or vice versa.  It’s a very tenuous relationship that Americans have with the food as it is, and the ever-changing dietary guidelines we’re expected to follow do nothing to strengthen our faith in the empiricism innate to each individual on the planet.

It’s pretty well understood at this point that sugar is definitely harmful (in the quantities we consume it, anyway).  So if cholesterol isn’t harmful, then at least that eliminates one of the false possibilities we might otherwise waste our time with in future metabolic research.

Fluoride? In MY Drinking Water? Big Deal.

I wanted to title this entry “Misinformation,” which seems to be a recurring theme among many areas of public opinion, and as a result, among many scientific circles.  Misinformation is easier than ever to spread thanks to the internet.  Google any vitamin or nutritional supplement you can think of and you’ll undoubtedly find the following:

1. Websites that approve of their safety
2. Websites that approve of their efficacy
3. Studies showing evidence for or against common health claims
4. Websites decrying them with or without basis
5. Websites that implicate them in a larger governmental/corporate conspiracy

For example, take raspberry ketones.  These are just ketones (a common type of organic molecule) that come from raspberries that account for the fruit’s particular smell.  Somehow, the health benefits of taking raspberry ketones as a supplement caught on, and they have become a common staple in health stores all around the nation.  Unfortunately, science has not a single shred of evidence to back up any of the benefits that this supplement’s advocates claim:

“Although products containing this compound are marketed for weight loss, there is no clinical evidence for this effect in humans.”   Source

Purported health benefits include effortless fat and weight loss, improvements in metabolism, and almost anything else that sounds even remotely plausible on the bottle, mostly pertaining to healthy weights.  Of course, there are studies showing some amount of lipid oxidation (fat burning) in mice cells, with a lot of “potential” and “possible” to go along with the research.  In short, this product is a prime example of baseless advocacy for a product that is so popular it has been featured and endorsed Dr. Oz,  who appeared before the senate for his potentially exaggerated claims about weight loss products, including Green Coffee Bean Extract, which is the new Raspberry Ketone.  Sure, preliminary results may hint at some potential benefits, but when the endorsement of a product is 1,000 miles ahead of the science backing up those claims, we’re seeing the cart before the horse and calling it correct.

The point of the above rant is that misinformation is everywhere, and there are few topics more controversial than water fluoridation.  Tap water fluoridation was implemented 70 years ago in the USA, and unlike Green Coffee Bean Extract, we’ve had the better part of a century to study its effects and as a result can vouch for its efficacy.  Note that studies confirming the benefits here do not counter the argument that fluoridating water is a form of “mass medication.”  That is certainly more of a political or social issue than a scientific health issue, and can’t be proven or disproven by science.  However, over the decades we have seen that it works to prevent cavities in people of all ages, and since it doesn’t affect our daily lives or the taste of our tap water, we tend to ignore it.  But how does it work, and why is it such an ongoing to topic of controversy?  We can at least attempt to answer the former.

You know the fuzzy feeling you get on your teeth when you haven’t brushed them for a few hours?  This is due to colonies of bacteria that are living on your teeth.  You’re actually feeling the fuzzy “biofilms” that bacteria is groups tend to form.  A biofilm is tougher than the sum of its parts, and they stick together in a cohesive clump of organisms.  Now, all bacteria have certain conditions for acidity, temperature, and moisture that allows them to grow most easily, and a particular species named S. mutans does very well on our teeth.  When bacteria eat their food and produce metabolic wastes, they churn out acidic by-products.  Think of it like drinking a soda, which is very acidic.  You may have heard urban myths that colas can dissolve a tooth if left overnight, which is a claim based on the soda’s highly acidic contents.  But even bacterial acid wastes, which are thousands of times less acidic than soda, can damage your teeth.  This acid eats away at the enamel, the hard outer layer of your teeth, dissolving it.  The result is a tooth that’s less protected from the outside world, and any bacteria already present will have an easier time getting into places they shouldn’t, and they can seriously damage the inside of your teeth.  This is how a cavity is formed.  Keep in mind that bacteria generally eat sugars as their preferred meal, so any sugary foods or drinks should have you brushing your teeth immediately afterwards to help slow the colonization of your teeth.

The drawing to the right shows how it looks when your enamel gets dissolved.  A cavity is literally a hole in your tooth from long-term dissolution of your outer enamel.  To help prevent this, the USA adds fluoride to its water.  You might suspect that perhaps fluoride kills bacteria (and many halogens can do so), but in this case, fluoride is actually more like a band-aid.

Fluoride in your tap water enters your body and blood, and eventually becomes part of your saliva.  You do excrete it through your urine, so it’s not building up inside you or anything.  Instead, the little fluoride that ends up in your saliva goes to your mouth, where you unconsciously spread saliva around all the time.  The saliva glands under your tongue and behind your cheeks do a great job of keeping your mouth lubricated, and that fluoride really gets everywhere, including coming into contact with any teeth that many had their enamel removed by bacterial decay.

When fluoride contacts these teeth, it reacts chemically with any remaining enamel and forms a very hard outer coating.  Interestingly, this layer is actually harder and tougher to penetrate than our normal enamel, meaning that it’ll be harder for bacteria to break through our newly refreshed enamel layers.  It’s really that simple.  As long as you try to take care of your teeth, it’ll be a lot harder for anything to go awry with them.  But if you keep up with old habits like not brushing your teeth after eating or drinking sugar-containing stuff, it’s not going to do a whole lot for you long-term.  It’s an elegantly simple method of keeping bacteria and cavities at bay, at least for a little longer than normal.

Remember the quote above showing that raspberry ketones don’t have any documented effects on humans?  Contrast that quote with this one:

“Existing evidence strongly suggests that water fluoridation reduces tooth decay. Consistent evidence also suggests that it causes dental fluorosis, most of which is mild and not usually of aesthetic concern.^[10] No clear evidence of other adverse effects exists, though almost all research thereof has been of poor quality.” Source

What can we gather from this excerpt?  For one, we are fairly certain that fluoridation does have health benefits and can help prevent cavities.  However, in all our research we have not yet found a suitable experiment to determine what, if any, negative side effects there may be.  So we know that it’s good for us in some ways, but we’re not so sure that it’s not bad for us.  Kind of an interesting dichotomy, isn’t it?

At this point you’re likely in one of a few camps:

1. You dislike water fluoridation because the negative health effects haven’t been determined.
2. You like water fluoridation because it can help prevent cavities.
3. You’re still ambivalent on the subject, because while there is evidence it’s helpful, that’s not good enough when we don’t know what negative effects there may be.
4. You think the topic is super boring and you’d rather just take your Green Bean Coffee Extract and Raspberry Ketones.

Whatever your mindset, my goal is not to try to change it.  My goal is for you to learn something new today about just one aspect everyday life that that’s hiding a very interesting story.

Why do a bowling ball and a car fall at exactly the same speed?

Today, we all know that any two objects, if dropped from a 20-story building, will fall at the exact same rate and hit the ground at the exact same time.  For many hundreds of years, though, this was considered counter-intuitive, and indeed, incorrect.  While society has been asking scientific questions about the movement of matter for over 500 years, an acceptable answer arrived much later than this.  A book by Isaac Newton published in 1687 explained the mathematical reasoning behind falling objects, and his theories stand today as the best models we have to predict gravitational acceleration.

So what does all that have to do with falling objects?  When I was younger, I was sure that a car and a bowling ball would fall at different speeds – after all, if the car is many times heavier, then it’s pushing downward at an equivalently high rate, and so it should fall faster.  This logic was widely held before Newton (and his predecessors) broke new ground in explaining the behavior of gravity.  Even if you know today that all objects fall at the same time, you might not know exactly why this is.  As it turns out, the answer is unbelievably simple.  It’s actually pretty amazing how obvious it seems in retrospect, but we have centuries of research to draw on, so whatever.

So why do all objects fall at the exact same speed?

The answer goes back to Newton’s second law, perhaps the most famous second law (with the possible exception of thermodynamics’s second law), which states that F = M * a. In English, the force acting on an object can be indirectly calculated by finding the object’s mass and also by looking at how fast it’s accelerating.  If we know these two things, we can come up with a numerical response to the “amount of bashing” that this object is experience.  You can push a car up a hill at a very slow rate, but if that rate is constant (say, one foot per minute), then this equation tells us that no forces are acting here.  This goes back to Newton’s first law – just because an object moves doesn’t mean it’s experiencing force.  When you’re pushing a car, your force exerted on the car is exactly cancelled by the resistance of the car to movement.  Sure, you have to exert some force to get the car going, but once it’s moving smoothly, there are no more forces at play.

So if we look at dropping objects off of a building, we can use this same principle: force equals mass times acceleration.  Since it’s not true that all objects have the same mass (does a car “weigh” the same as a pencil?), that means the 2 other variables in F = M*a must always equalize, no matter the object.  And indeed, this is the case.

First let’s look at our car.  It has a very high mass, and we know that acceleration is constant on earth, so that leaves only force, F, as the changing value here.  That’s no problem – for now, let’s say that a falling car has more force acting on it than a pencil.  At the same time, our pencil has much less mass, but still falls with the same rate of acceleration, so its force must also be much, much smaller than the car’s.

Here’s the final jigsaw puzzle piece here: the gravitational force between any two objects depends only on their masses.  It will change depending on the mass of each object, but no other factors matter.

Let’s drop our car off the side of a building once more, and say that it has ten times the mass of a motorcycle.  The car will have ten times the force acting on it as explained by F = M*a, but because the mass is ten times higher, the car is ten times more “resistant” to being moved.  Let’s see this in our equation:

Force on an object = its mass * its acceleration

F = M * a

Since we said our car is ten times heavier than a motorcycle, we’ll add a 10 in front of the mass.

F = 10 M * a

The force, then, is going to be 10 times higher than if the mass were equivalent to just 1 “unit.”

10 F = 10 M * a

Our 10s cancel here, and acceleration is STILL equal to F / M.  Repeat this calculation with a pencil, and you’ll see the same result: a = F / M. In other words, a car that’s ten times heavier than a motorcycle will experience ten times the forces, but this is only because its mass is ten times greater.  Since the force depends on the mass, we expect this to happen.  But because of the mass being ten times greater, the extra force pulling on the car is exactly cancelled by its high mass.

Stephen Hawking explains this perfectly in his book, A Brief History of Time.

One can now see why all bodies fall at the same rate: a body of twice the weight will have twice the force of gravity pulling it down, but it will also have twice the mass.  According to Newton’s second law, these two effects will exactly cancel each other, so the acceleration will be the same in all cases.

In fact, this mystery that eluded mankind for centuries is adequately explained by the simple equation we’ve used above.  There are no complicated numbers, constants, or imaginary numbers.  There’s no calculus, no slopes and no polynomial factoring.  The equation is so simple that it almost seems impossible, but you can use it just as we have here to explain exactly why everything falls at the same rate.  Kind of nuts, isn’t it?

Your car does calculus like a pro

You may have heard of the branch of math called “calculus.” To me, it always carried a connotation of “the hardest general math class in high school or university,” and after just a few weeks studying it, I’m not sure it’s all the horror it’s cracked up to be.  It’s a branch of math that lets us measure things that are changing as they change: if you drive 10 miles in 10 minutes, then your average speed was a mile per minute.  And if you drove 0 miles the first five minutes, then sped up to 2 miles per minute for the last 5 minutes, your average is still a mile a minute.  In our daily life, measurements like this really are taking the average of something – feet per second for a falling raindrop or degrees per hour, for example.  But most of the time, these things aren’t changing at a static rate — they’re changing quickly at some points and much more slowly at others.  Wouldn’t it be cool if we could measure these changes second-by-second to get a more accurate idea of how they change?

Calculus is nothing more than the study of change.  Specifically, we take a few concepts and apply them to the math that we already know.

The car example is not only one of the easiest to relate to, but it’s a perfect way to grasp just what calculus is all about.  For a car’s speed, you might use calculus to calculate the exact speed at exactly 4 minutes into a 10 minute trip.  Perhaps you’re moving at 1 mile an hour, or perhaps you’re not moving at all – calculus will show you your speed at any instant in time over the 10 minutes you drive.  But let’s show how we can take simpler math and upgrade it to super advanced by-the-second math.

What dose an odometer do?  It measures miles, of course.  If a drive takes you 45 minutes and you traveled 10 miles, then it took you 4.5 minutes per mile (you might be driving through New York City  if you’re driving this slowly).  All you have to do is mark your starting mileage and time, then when you’re done, you get your ending mileage and time.  Divide the change in miles by the change in time and you have your average speed.  This is algebra, or even simpler math: it’s something that most of us can do without breaking a sweat, perhaps because we actually use it quite often.  We might want to know how efficient the car is (miles per gallon), or how long it takes to get to a friend’s house.

So a car’s odometer measures average speed by keeping track of miles.  If you remember to record the time, you have the average speed.

So where’s the calculus?  Well, think about what your speedometer does.  You might argue it does the same as the odometer — with a little math, it gives you your mileage and time, but it’s really measuring your instantaneous speed directly.  If you go 25 MPH one minute then 35 MPH the next, you can look down at the speedometer during each of those minutes and see these numbers.  You can watch the needle go smoothly from 25 to 35 MPH, and you know with certainty that your speed changed during your trip.

Where an odometer measures averages, a speedometer measures instants — and that’s all calculus is.  It simply upgrades the concept of measuring averages to the concept of measuring instants of that same set of “stuff” that you’re measuring.

This graphic shows a curve that we can’t use regular math to solve – if this is our speed during the trip, we can use calculus to find out our exact rate of change of speed at one of these valleys.  You can find the speed by choosing an X value and following it to the corresponding Y value, but that only gives you a single instant’s rate.  Calculus will let you not only get this single point, but if you’re decelerating, it can give you the exact rate that you’re slowing down.  That’s something that can’t be done with traditional math.  If you’re accelerating, how in the world can you figure out by how much you’re speeding up.  That’s where the calc comes in, and it’s something your speedometer does constantly.

What’s really fascinating is that your car does this without a supercomputer – the needle and the speedometer it travels on are analog methods of solving a highly complex math problem, just like the hands of a clock.  Think about it this way: a clock will only show you the time down to the minute or second, but it doesn’t show you milliseconds.  You can estimate milliseconds from looking at the clock, but you can’t get them from the clock’s measurements.  The clock just isn’t that accurate.

So every time your speed changes, you’re really giving your car a calculus problem to solve.  You’re asking it to keep tabs on your speed as it changes second-by-second or millisecond-by-millisecond.  Your car does it all without griping, and the result is a little needle that jumps up and down the speedometer as you drive.

On a side note, Calculus can be used for many other cool things: if you can find the area of a square with algebra or geometry, then you can use Calculus to find the area of some many-sided shape your child drew at school.  Anything that’s changing so much that we can’t use algebra can likely be tempered with some calc.

I don’t know about you, but that’s just astounding to me.  Math is truly amazing sometimes!

Anti-bacterials: Dangerous Whack-a-Mole

By now you’ve probably heard about some of the controversy surrounding the use of anti-bacterial products like soaps and hand sanitizers, as well as the equally common use of antibiotics to treat certain infections in the human body.  What may not be immediately clear, however, is just how important understanding the argument is.  It ties together evolution, humanity, and organism diversity in a way that form a scary harbinger of what the future may bring.  Indeed, anti-bacterials are probably the biggest “little problem” that the average person may not even think about.  Every use of such products is going to cause major trouble down the line for you, your children, and their children.

I’m certainly not here to be persuasive: this is, after all, an informative blog.  My goal here is to inform you about facts that may not be common knowledge, and try to explain in really simple terms why this topic important.  It’s easy to get bogged down in the “science-y” jargon and concepts, so we’ll pretty much skip them entirely.  It’s just crucial that I get this point across in a way that’s easy to understand.

First off, we know that human beings are all unique – nobody in my family has the exact same height or hair color as me, and there’s nobody I know that has the exact same body type and shape.  Unless you’re a twin, you are a unique human being whose genetic make-up has never before existed in a single person.  Some people are deathly allergic to peanuts, while other can binge on ice cream and never gain a pound.  The point is that humans are all different on both the outside and the inside because of the nearly infinitely combinations of genes we get from our parents.

The funny thing is, bacteria are the same way.  Even though we tend to think of them as much simpler creatures, some bacteria are more well-suited to certain conditions.  Some might thrive in a hotter climate, while others need a more acidic environment to stay alive.  One other factor that often goes unaccounted for is resistance to antibiotics. Just as every human has a unique immune response when there’s trouble, each member of a bacterial species has its own response.  Some members of the same species may fare better or worse than others because of these differences.  It’s like if two E. Coli bacteria, one from Jamaica and one from Alaska, were to face off in battle — their strengths and weaknesses would be different because they come from different environments.

When you use anti-bacterial soap, the most common active ingredient is called triclosan.  Others exist, but this is the one you’ll see more of the time.  The bacteria that are more vulnerable to triclosan’s effects (namely, killing them) will definitely die quickly, but others may have slightly better resistance to it.  Triclosan kills bacteria by preventing them from creating fatty acids, which make up the bacterial cell’s outer membrane.  Without this membrane, they’re sunk.

But say we use that same triclosan on a colony of bacteria which, over time, has acquired mutations in its genes that change its membrane structure a little.  Now it might use fatty acids and some proteins.  If you use triclosan on these bacteria, they may not die, because you’ve risked everything on the “destroy the membrane” tactic, and these bacteria just happen to have a different membrane.  It’s not that they developed this new membrane to thwart you — your use of triclosan and their developing new membrane types both happened independently.

So if you combine our new membrane colony with some other standard membrane bacteria, you get a more realistic picture of what’s actually living on your body.  Our bodies contain many different kinds of bacteria, and some may have more resistant membranes to triclosan than others.  When we use an anti-bacterial soap, all the ones with the “standard” membrane will be killed, but the ones with the new and improved membrane may live.  They’ll continue to reproduce and grow.  Now, all the triclosan in the world couldn’t kill them. It’s as if you shut off all the power to your house, and the three desktops that plugged into the wall sockets lost power, but the laptop with an internal battery remained functioning.

The problem is that we continuously kill the bacteria that are most susceptible to triclosan, while the ones that are more resistant continue to breed and grow.  After some time, triclosan won’t do a thing, and these bacteria can still exert all the same pathogenic power they had before, except now they’re tougher to beat.

So, we might look for another solution: we may look for a different chemical that works a different way, and that will be successful – for a while, at least.  The exact same thing will happen over time as random mutations in bacteria accumulate to the point where their physical makeup becomes somewhat resistant to our methods.  This is, in fact, exactly how the flu virus comes back each year with a new strain: last year’s strain had a certain genetic makeup, and we developed a vaccine to combat that makeup specifically.  This year’s strain doesn’t work the same way, so last year’s treatment won’t do a thing to it.  

The scariest part is that bacteria reproduce incredibly fast.  It may take you 30 years to bear children, and then it takes your children 30 years to bear their children.  Bacteria can split in two in a matter of minutes, and their growth is exponential.  You start with one, then two, then four, eight, sixteen, etc. It would be like if human babies were born and then gave birth to their children, all within 30 seconds.  Bacteria grow so fast that it’s hard to imagine it.  And all the random genetic changes occur that much more frequently, simply because they’re creating new organisms much faster.

So using anti-bacterial products is sort of like saying, “I’m going to kill all these bacteria, even though I know that in a few years from now they might become resistant to it.”  It’s like shooting yourself in the foot, or setting your future offspring up for a slightly more treacherous world.

Now for the science-y explanation: When you use anti-bacterials, you’re selecting for resistant strains to survive and re-populate in greater proportions.”  Theoretically, we may kill all the bacteria on earth that are vulnerable to triclosan, and now not a single species will respond to it.  Now triclosan is truly useless.

The truth is, plain old soap and water are just as good as anti-bacterials: soap works because it’s like oil and water in a single molecule: it has an oily end, which bonds with oil, and it has a watery end, which can be dissolved in water.  This kind of treatment is just as effective because it operates on the molecular level with the concept of solubility.  It’s a much more basic treatment than triclosan because it affects a more base property of all matter in the universe.  Triclosan is like taking a sniper rifle and shooting a single bear from 1000 feet away, not realizing that his bear buddies are charging towards you.  But soap and water is more like sending a flash flood their way, wiping out all of them and keeping you safe.

Thankfully, awareness of triclosan is getting around, and I hope for future generations that its popularity wanes with time.  As we said above, the true danger isn’t in the near future: most of us will be long gone before this starts to become a real issue.  But our children just might have to deal with it in a huge way.

Have you heard of penicillin?  It was the first big antibiotic medication, and people use it for all kinds of treatments.  After a few years, though, we started to see the first bacteria that were actually resistant to it.  So, we went on a hunt to find another active ingredient that was as good as penicillin was at first.  We found one, and used it just as liberally, and wouldn’t you know it, bacteria eventually became resistant to that too!  This has happened not just twice but many times over the last few decades – it’s like we’re playing Whack-a-Mole, but every time whack one down, another one pops up. Using triclosan is going to lead to the same problems we had with penicillin – eventually, we’re going to need to find something new.  Is this honestly the best strategy that we have for dealing with harmful bacteria? What if someday we run out of effective methods, or an outbreak occurs while we’re still searching for “the next big treatment?”

Whack-a-Mole, indeed.  There’s only one hammer to whack moles with, but a new mole will always pop up.  It’s a losing game if you’re always reactive, rather than proactive.

The only way to win is to not play at all.

 

Why You Should Never Water a Plant’s leaves (Breathing 101)

It’s considered good advice not to water a plant’s leaves.  If you have to water a plant from standing position, you’ll pour water from the top of a plant, and it will spill down the leaves and into the soil.  Sadly, this is probably the worst way to get water to a plant, and it’s analogous to waterboarding in some ways.  That’s an assertive analogy, but as we’ll see here it’s actually pretty accurate.  In short, you always want to water plants ONLY at the roots directly.

 

You probably already know that plants get their water by absorbing at the roots.  Water drains into the soil and the roots take it into the plant’s stem, and it moves upwards through the plant.  You might notice a small problem called gravity here — how could a plant with no muscles move water upwards along its stem when the force of gravity is so much stronger in comparison?  Plants actually have a few nifty tricks to get around their lack of muscles.  The magic starts at the plant’s leaves, so we’ll check in there first.

Leaves are exposed to the sun and the air, and as a result they’re constantly losing water from dehydration.  They need a constant supply of water from the roots, moving upwards, to keep them alive and well.  When leaves lose water to the air, it’s called transpiration.  It’s sort of like sweating (perspiration) in humans.

 

If you’ve ever seen water bend upwards at the very top of a cup, it’s because water molecules are attracted to other water molecules.  They have a certain amount of cohesion to each other, and that’s why rain tends to form drops – each water molecule on the outside of the drop is more attracted to the next inner molecule than it is to the surrounding air, and so they huddle inwards and stick together.

The same thing happens in a plant’s “veins” – As water is evaporating from the leaves, the water molecules attracted to those about to leave are attracted upwards, replacing the water just lost.  Not only this, but just water will climb the sides of a glass, the same happens in a plant’s vessels — water bows out at the sides of the vessel wall and moves upwards against gravity!

When you get water all over a plant’s leaves, the water molecules in that leaf can no longer evaporate away, and water from the roots will cease to flow.  You’ve blocked the water from exiting the leaf, which causes a chain reaction farther down the plant that prevents upward flow.  Repeat this experiment enough times and you’ll deprive your beloved plants of the water they need to stay alive even though you’re drenching them from head to toe!

It’s quite easy to forget this concept, but it makes all the difference.  Feed your plants by watering the soil directly, and let the plant transport its own water.  It’ll reward you by growing bigger and stronger, and if you’re lucky, some more delicious fruit!

 

 

Your Favorite Band Loves Electromagnetism

We’ll do a quick-ish topic this time.

You probably know that the speed of light is the theoretical speed limit that anything in the universe can obtain.  Any faster than that and you’re going backwards or forwards in time and ageing slower than your sister or something nutso like that.  We don’t tend to notice the speed of light in our day-to-day, but here’s a great example of just how incredibly fast it is.

The speed of light is three hundred million meters per second, or 186,000 miles per second.  This doesn’t really do it justice though, so let’s take an example.  Say you’re at a concert and your favorite band is headlining.  You’ve got a great spot 100 feet away on the balcony.  Meanwhile the stage crew has set up speakers all throughout the room so that everyone hears the music at the same time.  When the singer sings into the microphone, what do you hear first: his voice as it travels through the air from his mouth to your ear, or his voice as it enters the microphone and is emitted from the speakers next to you?

We can do some simple math to figure it out, and the answer may make your jaw drop, as it did mine.  The speed of sound in a typical room at room temperature is 343 meters per second. If you’re standing 100 feet away, it takes roughly 0.292 seconds for the singer’s voice to reach your ear.

If, on the other hand, we think about the speaker’s role in this problem, we come to a strange conclusion.  Before we lay it out, a quick primer: the speaker has essentially translated the singer’s voice into an electromagnetic wave.  You might know such waves as the radio waves that ping down to your car so you can listen to Tik Tok on the ride to work in the morning.  Never mind that there are tens of millions of those waves hitting your car every second so that you can listen to NPR: every single wave in this category travels at the speed of light.

What’s included in this category?  You’ve heard of many of them: ultraviolet, infrared, radio, X-rays, and visible light all travel at the speed of light.  Since our singer’s microphone sends his voice to the speakers, the speakers will emit his voice at the speed of light in the form of a radio wave.  The waves from the speaker would hit you in 0.000 000 3 seconds. Makes the 0.292 seconds seem pretty slow by comparison, huh?  If we compare these two speeds, we find that the waves from the speakers are traveling 884,850 times faster than the sound waves in the room.

Let’s try one more example for extra fun.  Say you took a business trip to China and your favorite band is playing in New York at this very moment.  The distance between China and New York is 11,200 kilometers, or 11,200,000 meters.  If you strained REALLY hard in China, you might just hear your band’s singer 0.0373 seconds after your wireless radio picks it up.  Even though you’re literally on the other side of the world, you’ll still hear the singer almost 8 times sooner than someone who’s standing on the balcony just 100 feet away from him.  In fact, if you wanted to figure out how far away from New York you’ve have to be in order to hear the singer at the same time as somebody 100 feet away at their great balcony spot, we can do some quick math:

X m / 300,000,000 m/s = 0.292 s.

The above equation says “if I want the singer’s voice to reach me in 0.292 seconds via radio waves, how far away from him do I have to be?”  Turns out you’d have to be 87,600,000 meters away.  Just how far is this?  You’d need to be in a space ship traveling to the moon and have already covered 25% of the distance.  In other words, unless you’re an astronaut, radio waves are giving you a aural advantage in any situation.

Pretty nutso, huh?

Light Bulbs are Literally a Waste (and that’s the point!)

 

We often take for granted the ubiquity of electric lighting is these days.  Just a few hundreds years ago we didn’t even know the basic principles behind electricity.  All we could do is cower at lightning every once in a while, and if the stories are true then maybe you’d tie a key to a kite in a lightning storm to see what happens.  And yet in other parts of the world (if you’re from the US/Canada), lights are a hot commodity.  We know they run off of electricity, but one may be hard-pressed to really explain just how the things work.  It’s actually much, much simpler than you thought (probably).

There’s a fundamental concept of energy transformation in science that says any time you convert between types of energy, you lose some of it in the process.  It’s like saying you can go to the casino and blow a thousand bucks on slots, and you might break even at the end of the day, but the time you spent pulling the lever is now lost.  In terms of energy, we might say that if you drop a rock off a cliff, the energy it has when it gets near the bottom is mainly in the form of speed – you wouldn’t want to be standing under it, would you?  It’s chock full of energy that was transformed from potential to kinetic (in this case, from its high position to its high speed during the fall).

In the same way, light bulbs and all concepts of electricity essentially incorporate this energy loss into their design.  Commonly the energy that’s lost during a transformation is either heat or light, or both.  Hm… can you think of any devices that put out heat and light?  Hopefully there’s a light bulb over your head right now, because that’s exactly what we’re referring to here.  The bulb on the left here is getting so hot that it’s producing light.  Ever wonder why a stove’s coils burn red hot?  That’s light being emitted along with heat.

The bulb itself is little more than a single piece of wire that’s conducting.  We know intuitively that rubber doesn’t conduct electricity that well, but most metals do, so we use metallic wire here.  You run your single wire from an initial power source and through the bulb, making sure that only a single path exists and that the wire never touches itself farther down.  The wire comes out of the bulb and connects back to the power source, making a circle, or a circuit.  If you’ve got a D battery at one end, you can hook your piece of wire to the two ends of the battery, run the body of the wire through a bulb, and produce some light from it!

The trick here is that inside the light bulb there is a section of tightly coiling wire.  You can see it clearly in the picture above.  As electricity flows through this section, it encounters resistance, just like you might if you were running down a straight hallway and suddenly had to turn multiple corners as fast as you possibly could.  The electricity is forced to slow down here, and because all energy is conserved, the energy that was previously shooting down the wire is split off into an equal magnitude but different form of energy, namely, heat.  As a result, the wire gets really, really hot.  Rub your hands quickly together and the resistance between them causes heat to be generated, which we love to do in the winter when it’s freezing cold outside.  It’s the exact same principle – friction between two objects “generates” heat energy.  Also important here is that we can change the resistance to virtually any value we please, making it easier or more difficult for electricity to pass through or generate some heat.

As the wire gets hotter and hotter, it eventually starts to put out light.  This light energy is another manifestation of the wasted energy from this transformation process.  But this is exactly the reason we use light bulbs in the first place!  What we’ve essentially done is force energy into a conducting wire, force it into a bulb, and finally force it to splinter off into several kinds of energy that are observable in different ways.  We can feel the heat from a light bulb, we can see the light it emits, and we can test the wire to see whether there’s still energy flowing through it.

In essence, the resistance we give the light bulb at the coiled section expends the energy we’ve fed it, so the result is a great deal of heat and a great deal of light.  The interesting part is that a light bulb is basically just the guts to any electric appliance, like a microwave or a refrigerator.  If you had your wire connecting to a microwave instead of a light bulb, you’d get some power into it and you could make hot chocolate.  Light bulbs by design don’t have any useful function except to release electrical energy – they can’t power a hair dryer by themselves.  All the energy you’d spend charging your phone at night is instead released by a light bulb to provide a continuous stream of light.  Here’s the kicker though: you might guess that only a small fraction of the total energy goes towards light and heat release.  Unfortunately, if we take 100 units of some arbitrary energy and send it through a light bulb, only 3 of those units are really producing the light we need –all the other 97 units are wasted as heat, which is why leaving lights on in the summer makes a room really hot (or why a spotlight on a school’s auditorium stage makes you sweat!)

This huge waste of energy as heat that we don’t need is an ongoing problem as we try to develop better light bulbs.  A big hurdle is that the light we need from light bulbs is really a result of the release of heat, so it’s hard to have one without the other.

When you think about it, the very purpose of a light bulb is to be wasteful.  We want that electrical energy to be released, rather than contained in the conducting wire, because its release provides us with a huge amount of heat and a relatively small amount light.  A light bulb’s energy  disperses as heat and light much like any electrical device might, but in a much greater quantity than any hair dryer or electric razor.  Most of the energy we put into those devices actually goes towards useful work (the hair dryer spitting out hot air, or the razor’s blades whirring).  On the other hand, the light bulb is like an appliance without a function – energy runs through it, is entirely wasted, and just happens to produce some light as a by-product.

As for the eventual heat death of the universe due to the effects of entropy, well, that’s a discussion for another time.

It’s a Math, Math, Math, Math World

Consider a mental inventory of your own knowledge for a moment.  Picture a big pile of all the things you know: concepts, processes, ideas about the world and humanity, equations, whatever.  It’s hard to quantify but I bet you’ve got a decently-sized pile.  Now next to that stack up a pile of the things you don’t know: all the subjects you wished you’d had time for in college, the equations that we’ve yet to derive, the contents of the universe, and so on.  You’ll find that the pile of unknowns is to the pile of knowns as planet earth is to an electron in a single atom of helium.  That is to say, the amount of stuff you or I or even collective civilization knows about the world is a lot, but it pales in comparison to what we wished we knew.

All of this to say that there are plenty of things we’re confident about.  We live in a world where the newest sub-atomic particles are being tested and analyzed, but we still can’t quite figure out how our brains really work.  We can send men to other planets, and yet we’re sorely lacking if asked for a good reason why humans need sleep at all.  Our world is huge and unfathomably complex, and yet we have somehow (and I’ll never believe this) have been able to distill at least parts our world down to math and equations.

If you throw a ball up in the air, could you give someone a qualitative description of its action?  “It left my hand and shot upwards, then slowed down to a point and came back down to earth pretty quickly.”  Well, this isn’t exactly a scientific description, so how about something quantitative?  Not only can we determine speeds, accelerations, and distances traveled by nearly any object in motion, but we’ve learned that the variables that go into the motion of such an object are really few in number.  Armed with only a starting velocity, acceleration, and stopwatch, we can accurately determine the motion of objects.  In essence, consider everything that has ever left the crust of the earth and has been temporarily under the control of only the gravitational force.  We can describe its motion near-perfectly.  Indeed, we can use the equations to the right, each of which are essentially the same statement but re-arranged four different ways.

In my mind, the fact that we can need only 3 or 4 variables to describe motion on earth is astounding — there are few, if any, hidden variables that we don’t yet know about in many of our “knowns.”  Compared to the stuff we don’t know, we have somehow culled all the things we do know about motion in the right combination such that “motion of objects” is contained in our “knowns” pile.  The odds of this happening in any universe are, in my mind, astronomically low, but of course I’ve got no evidence to back up that claim.

We can measure invisible electric and magnetic fields with pinpoint mathematical accuracy and tell our friends the time to the nearest millionth of any given day (excluding leap seconds here).  This is stuff we know and have tested over and over – somehow these properties of earth and the universe ended up in our teensy weensy “knowns” pile.

One more example: Say you pump some oxygen gas into a room with no ventilation.  If you know the temperature and pressure of the room, you can use a very simple math equation (PV = NRT) to find out the volume of that room (and consequently the oxygen gas you pumped into it).  Let’s look at that equation a little closer.

The pressure exerted by a bucket of oxygen molecules: PV = NRT (where P is a pressure, V is a volume, N and R are constants, and T is the temperature)

Scientists agree that the product of pressure and volume is numerically equal to the temperature and two constants in any given situation.  Of course there are some correcting factors for advanced chemist fanatics, but even they’re not too terribly complex.  In short, this equation with only 3 variables and 2 constants fully describes the behavior of nearly any gas in any size room and at any temperature.

Have we really distilled molecular behavior into such a simple formula?  It’s kind of hard to believe, but this is once again in our “knowns” pile.  The whole point of this post is to spark a thought in your mind: with all the stuff that we don’t know, we still have lots that we DO know, and the stuff that we do know can sometimes be the simplest principles.  We can combine the very firm theory behind the laws of motion and flight to get airplanes running; we can measure the density and buoyancy of any liquid matter inside a column and then find the pressure it exerts at any depth inside the column.

Someday we’ll be able to map out the motion of atoms during nuclear fusion, or realize that the perfectly efficient engine is just a combination of the right four or five variables.  There’s so much to learn and so much to know that we haven’t even begun to study, and once we’ve got it all under our belts there’s a good chance that some currently unexplained phenomenon will be accurately represented with an equation — nothing more than a few letters and an equals sign.