Monthly Archives: October 2013

Why Can't We Travel Faster Than Light?

James writes: I know light is the fastest thing in the universe, but why can’t anything else go that fast? Is it just that we haven’t built a ship fast enough yet?

James, I am no physicist. I believe I understand the reason for “lightspeed” being the cosmic speed limit, but I could be wrong. Here goes my best shot:

The hard part, to me, is why light travels at a constant velocity – and why that velocity is 299,792,458 meters per second (in a vacuum; going through air or other media slows it down). I have no idea why light travels at exactly that speed, instead of going faster or slower. But Albert Einstein’s famous relativity equation – E=mc² – explains why we cannot build a ship that goes that fast.

In the relativity equation, “E” stands for the energy of an object. The “m” on the right side of the equation is the object’s mass. And “c” means “constant”: the velocity of light. In math, a constant is a value that does not change. Variables are properties that can change. “E” is a variable, because the energy an object has can change. For example, if a karate master moves his fist very slowly towards a wooden board, he might push it out of the way, but the board will not break. But if the karate master throws a fast punch at the board, his fist will break through it easily. Why? Because his fist had much more energy when it was moving fast. Energy increases with speed; this is why cars (and passengers) are damaged a lot worse if they crash at high speeds than if they crash when moving slowly.

An equation is a statement that both sides are equal, like 3+2=5. The left side equals the right side. If we add to the left side, we must add the same value to the right side for the equation to be true: 3+2+1=5+1. Einstein’s relativity equation states that an object’s energy is equal to its mass multiplied by the square of a constant, “c”. The constant does not change, so if “E” changes, “m” must also change. In effect, an object moving very quickly becomes more massive.

More mass means that it takes more energy to accelerate. This is why a Ferrari can accelerate faster than a dump truck, even if the dump truck has more power. So if we build a starship and move it faster and faster, its mass will begin to increase. The more massive it is, the more energy it takes to make it go faster. As we approach the speed of light, the mass becomes so great that it would take an infinite amount of energy to make it go as fast as light. Since we do not have an infinite amount of energy, we cannot reach lightspeed.

That is as much as I understand about your question, James. I hope it helps. If there are any physicists in the audience who can explain it better, or correct any mistakes I have made, I will appreciate it.

Stay curious, my friends!

Old Dog, New Tricks: Part 3

October is here. More truthfully, October is halfway over! I have spent half the day improving my programming skills, which are…improving.

I have not created the killer app yet, but I have a few good ideas and an increasing understanding of how to translate them into functional code. I know what “architecture” means in the context of software design. I am 90% finished with the online course in the Ruby language available on Codecademy; 41% finished with the course in Javascript; working through C++ using CodeBlocks, and making progress in learning animation together with my son. He learns faster than I do, which is great because I love seeing him acquire a useful skill; it is also kind of discouraging because I used to learn that fast, and watching him makes me feel old. But it is inspiring as well, because he still likes to work with me and his energy and enthusiasm are contagious.

Maybe old and young people are meant to work together. Old people have more discipline, persistence, and experience; young people bring energy, imagination, and a fresh outlook to the table.

So I went to the library today and came home with a stack of books, half of which involve technology. October is here, which marks one year and a month since I started blogging. Eight months since I started learning about programming; five months since I had the idea of building apps. Three months ago, I set a goal for myself to have built an app that is good enough for people to want to pay for, within a year. I am starting to think that just might be possible.

If it sounds like I am tooting my own horn today, you understand me completely! I feel terribly proud of myself for starting to learn how to interact with technology at age 42, instead of just going “gentle into that good night”. Old dogs CAN learn new tricks.

And (with apologies to Dylan Thomas) learning a new trick beats simply raging against the dying of the light.

The Best Chocolate Story Ever

Everyone likes chocolate. Some people love it more than any other sweet food. Then there are the true chocolate lovers, whose appetite for chocolate goes far beyond what the rest of us can understand.

Chances are you know one of these “chocoholics”. You may be one yourself. But there was never a chocoholic like my grandpa.

Grandpa was what they call, in the part of the country where he lived, a Character. An avid outdoorsman, his hunting exploits were the stuff of legend; his fishing yarns were so extravagant he was disqualified from the annual Liars’ Contest – nobody else’s tales had a chance. Small business owner, city planner, backyard inventor of the only 100% effective  system for keeping neighborhood dogs from fouling a lawn…in other words, a Character.

And Grandpa loved chocolate. That’s an understatement. Grandma, who kept the books for their store, chided him for raiding the chocolate crates in the storeroom; he would eat up all their profit, she said, only half joking. Grandpa blamed mice. Grandma observed that the local mice were conscientious enough to throw the wrappers away when they ate chocolate from the storage crates.

One day Grandpa broke out in a rash. He wasn’t running a fever, so he didn’t worry too much; but the rash wouldn’t go away. His friend the town doctor was mystified. “It seems like some kind of allergic reaction,” he mused. “You’ve never been allergic to anything, have you?”

“No,” Grandpa answered. “No allergies.”

“Well, what are you eating?” asked the doctor.

“I don’t know!” replied Grandpa. “I eat all kinds of stuff – whatever’s for dinner!”

“We have to rule out some basic foods, then,” said the doctor. “Let’s isolate you for a week or so – take a vacation at your cabin. Make a list of all the things you take with you; jot down what you have for every meal. Hopefully when you come home the rash will be gone, and we can eliminate the items on your list.”

Grandpa didn’t hesitate. His cabin in the Rockies was his favorite place to get away and do what he loved most: hunt and fish. He loaded up the car with the bare necessities – including fishing tackle and his favorite rifle – and set off.

A week later he returned. The rash was worse than ever.

“Good Heavens!” said the doctor when he saw Grandpa. “You look worse than ever! It’s a safe bet that something you eat is making you sick. It must be something you took with you to the cabin. What did you eat up there?”

“Well,” said Grandpa, “I brought some flour, eggs, and cooking oil for pancakes. Had some bacon. Coffee, no milk. Trout from the lake – delicious!”

“None of those thing should have given you such a rash. Are you sure you didn’t eat anything else? Nothing at all?”

Grandpa paused. “I did have a little bit of chocolate.”

“Aha!” cried the doctor. “How much chocolate did you take up there?”

“A twenty-five pound bag of bridge mix…”

“What? No wonder you broke out in hives! How much of that bag did you eat?”

By now, Grandpa was getting defensive. “What do you mean, how much of it? I ate all of it!”

“Good Heavens, man!” roared the doctor. “It’s a miracle you’re still alive!”

Red-faced, Grandpa yelled back, “And that’s not all! I ate a ten-pound box of Hershey bars, too!”

The doctor threw his hands up in resignation. After Grandpa left, he made a phone call to Grandma; the result was a chocolate-free diet for Grandpa. The rash went away.

It’s all true, and it’s the best chocolate story ever. If you think you can beat it, you are welcome to try.

It's Bad Luck to be Superstitious

“Superstition brings bad luck.” – Raymond Smullyan

Do you avoid stepping on cracks? Does it make you worried if you spill the salt, or break a mirror, or walk under a ladder? Are you afraid something bad will happen if a black cat crosses your path? If so, you are not alone. Many people share these – and many other – superstitions. But where did all these beliefs come from?

Merriam-Webster’s online dictionary defines superstition as “a belief or practice resulting from ignorance, fear of the unknown, trust in magic or chance, or a false conception of causation”.

In everyday English, there are several reasons why the world seems not to make sense. One of these reasons is not having enough information to understand why things happen. It is easy to see patterns in the world around us; the human brain seems to be hard-wired for recognizing patterns. When we detect a pattern, we like to find the cause for the pattern. For example: on the twentieth day of every month, I feel a little more happy and relaxed than on other days. Why could this be? Is there something magical about the number 20? Not at all: I get paid on the twentieth of each month. But if you didn’t know that, and failed to guess the truth, you might find some other explanation.

Another reason for being superstitious is feeling afraid of what might happen. Nobody knows exactly what will happen in the future; yet some of us fear it and others do not. If you feel that you are in control of your life (whether this is true or not), you will not fear the future. If you feel that you have little or no choice in your life’s events, you will probably feel some degree of fear when imagining the future.

Finally, it is possible to believe that things happen for a reason, and still be wrong about the reason. For example, before discovering germs, most people around the world believed that diseases were a punishment from Heaven, or caused by evil spirits hovering in the air! (When Dr. Semmelweiss proposed in 1847 that diseases were caused by germs, the other doctors made fun of him. They got him kicked out of the hospital where he worked. They even had him declared insane and locked up. But that is another story!)

It is pretty easy to prove that diseases are caused by germs, so not many people are superstitious about sickness anymore. But many old superstitions are still popular, probably because there is a bit of truth to them!

Walking Under a Ladder

Walking under a ladder is considered bad luck in many parts of the world. The reason for this one is fairly obvious: the more you walk under ladders, the more likely you are to knock them over and get pelted with buckets of paint, metal tools, construction workers, and whatever else is at the top of the ladder. There is really no reason to be superstitious about ladders; it is just good common sense to walk around them instead of under them.

Breaking a Mirror

Breaking a mirror is supposed to bring seven years of bad luck. The reason for this is not quite as obvious as the one about ladders. Yes, when you break a mirror, there is always the risk of cutting yourself while picking up the pieces; but a cut will heal in seven days, not seven years. Why would anyone believe seven years of bad luck?

You may not think of a mirror as a valuable and prized possession, but they were until about 300 years ago. Before then, mirrors were hand-made by artisans who knew the secret of producing sheets of glass with a backing made from mixing tin and mercury. The process was difficult and only known to mirror-makers in the city of Venice, and mirrors were extremely expensive. Most people could not afford to own a mirror. If your family had a mirror, and you broke it, they would probably be upset with you for seven years or so! Thus the superstition.

Spilling the Salt

Like mirrors, salt was difficult to produce in the ancient world. This made it so valuable that the Roman army even paid their soldiers in salt (better than gold for a soldier, as salt also can disinfect wounds and keep meat from spoiling); this is the origin of the word “salary”. The only bad thing about getting paid in salt is that it dissolves in water; if you drop it in a puddle, your salary is gone. Bad luck indeed.

Black cats

As opposed to ladders, mirrors, and salt, there is no real link between black cats and bad luck. But to the superstitious mind, always looking for a reason (and not really caring if the reason is a logical one or not), black cats are handy scapegoats. Why? Because there are so many of them all over the place. Chances are, if something good happens unexpectedly, there will be a black cat nearby. The difference is that we never look for a reason when something good happens; we seem to think we had it coming. On the other hand, when misfortune strikes, it must have been that cat!

The comedian Groucho Marx famously said, “A black cat crossing your path signifies that the animal is going somewhere.”  Which makes sense to me.

Superstition in Sports

Superstitions are most often due to a sense of not being in control of things, of wanting to gain control, but without any real plan for doing this. It is interesting – and perhaps instructive – that superstition is much more common in some sports than others. More to the point, the sports that breed superstition are the ones where the player has the least control. Baseball players are famously superstitious; golfers a bit less. These sports involve hitting hard balls with hard clubs at very high speeds and at distances that allow the wind to become a factor. Tennis players are not prone to superstition. They are hitting a soft ball with a flexible racquet over a short distance, and are able to control the ball with a high degree of confidence. Likewise, you will never hear an archer or a rifle marksman talk of superstition. Their equipment is very precise and allows almost total control of the results. Tennis players, archers, and marksmen talk about skill, not luck.

And that is why I titled this post “It’s Bad Luck to be Superstitious”. The way to achieve success is to maximize your control over as many factors as possible. Anything else is probably a waste of your time and energy. Of course, control starts with yourself – which is why it is such an unpopular word. Until you are in control of yourself – words, actions, and thoughts – you can never really be in control of anything outside yourself either. Self-control is the key to every kind of success. It is also the end of superstition.