Friday, June 22, 2018

Snake Fight


I caught this photo of a black racer snake (huge; over 6 feet--2 m--long) capturing a poisonous copperhead snake (much smaller). Click to enlarge.

Monday, June 18, 2018

Can't Go Faster Than Light


Most of us have heard that the speed of light is the absolute upper speed limit of the universe. This fact was realized by Albert Einstein over 100 years ago, as he wrestled with what came to be known as his Special Theory of Relativity. He made an absolutely brilliant breakthrough, after struggling for several years with the dilemma of what would happen if we were able to race through space at velocities approaching the speed of light.... sometimes called relativistic speeds.

Einstein published his famous Special Relativity paper in 1905, at the tender age of 26, after having anguished for some 10 years over the paradox of travel near the speed of light. His special theory has a number of brilliant insights, but I'll focus here on just one of them: that the speed of light truly is an absolute upper speed limit. Nothing, not even light itself, can go faster. Here's a simple example of why that's true, and I'll use the TV series “Star Trek” as an illustration.

As millions of “Star Trek” viewers know, the USS Enterprise cruised through interstellar space, going “where no one has gone before,” and often at warp speed—that is, faster than light. Cap'n Kirk (or Cap'n Jean Luc Picard, in the follow-on series) would often command Scottie to move post haste to the next star system, let's say at warp factor 3—in other words at 3 times the speed of light. In critical circumstances, Kirk would even order a speed of warp factor 8! Sounds good, but those are impossible velocities. Here's how Einstein's theory demonstrates why.

Let's suppose that the Enterprise is temporarily based on Planet Zenon, where it is undergoing an extensive refurbishing. While the overhaul is going on, another (slower) starship, the USS Intrepid, leaves Zenon, headed for Earth, at 60% the speed of light, but they have inadvertently left behind an important document. Not to worry, says Cap'n Kirk; as soon as the Enterprise is ready to fly, we'll chase after the Intrepid at warp factor 3, catch up with them, and deliver the document well before they get back to Earth. 
 
Unfortunately, however, overhaul work on the Enterprise goes excruciatingly slowly. It's now four years later when Kirk's ship finally departs, at 3 times the speed of light. At that rate it requires them only one year to catch up with the slower Intrepid, which has been tootling along for five years, but has only gotten three light years away. Thus they meet in space five years after the Intrepid had departed—five long years of travel for the slow Intrepid, but just one for the speedy Enterprise. Still sounds OK. But...

I won't go in to all the details by using Einstein's complex equations of his special theory. Let me simply leap to the weird result that his theory predicts. From the perspective of the crew on the Enterprise (going at 3 times the speed of light), they left at year four and caught up with the Intrepid at year five. But if you use Einstein's relativistic equations, you get the impossible situation that, from the Intrepid's perspective, they were met by the Enterprise one year before (yes, before!) the Enterprise had even left Planet Zenon! 
 
I realize I've thrown around some possibly confusing numbers here, but the bottom line is, if faster-than-light speed is proposed, Einstein's special theory predicts an effect (the meeting with the Enterprise) before its cause (the finish of the rehabbing of the Enterprise). It's like saying that I celebrated my first birthday a year before I was born, or an arrow hits the target before the archer draws the bow! Clearly this is impossible. It's like time running backwards. We cannot have effects happening before the cause. 
 
Scientists have many times conducted experiments that verify Einstein's Special Theory of Relativity. The theory is right. In other words, the speed of light is an absolute upper speed limit. If it wasn't, things going faster than light would literally turn clocks backwards. Sorry, Cap'n Kirk, you can't do warp 3... and especially warp 8. But Star Trek was science fiction, after all.

Tuesday, June 12, 2018

Bearly Bearable

A few nights ago, just as dusk was falling, I was laid back in a reclining pose, listening to music. At these times, my eyes are most often closed, as I become immersed in the mood of the song. For some reason I opened them for a moment, to have my attention grabbed by the motion of something large and dark, at the corner of my vision. I turned my head toward the object, to spot a bulky, moving, black shadow outside—barely visible in the twilight.

Chompsky the dog was reclining on the bed, so it couldn't be him; besides this critter was much larger. Our neighbor has a huge dog, so I next wondered if his dog Duke had wandered by. But Duke has never visited us, and this creature I was seeing had a round butt and no discernible tail. Holy excrement! It seemed to be a bear!

I cut short the music and bounded from my chair, headed toward the window, through which I spotted the creature. My wife, alerted by my excited moves, asked what was up. A bear is wallowing around, not six feet from the house, I exclaimed! We got down on our knees, to better see it in a lower window, and watched it slowly turn this way, then that—obviously searching for food. Within a couple of minutes it turned and wandered ponderously up the hill toward the garden.

We looked at each other in wonder, trying to fully absorb the event. In the 34 years we've lived here, we've never spotted a bear. We have a neighbor who's told us several times that a bear resides in the area, but he's also the kind of guy who's convinced that our woods are crawling with coyotes and cougars. 
 
Several years ago we believe we were visited by a bear in the night, after surveying the destruction of our bird feeder and bee hive the next morning, but that was not proof positive that it was indeed a bear. I once spotted what appeared to be bear poop in the woods, but still no irrefutable evidence. I do not claim to be an expert on animal scat...it could have maybe been an overgrown raccoon, for all I know.

As we tried to accept what our eyes had viewed, we wondered if the bear was still around. Was it up there, destroying the garden? Had it decided to attack the trash can, as was done a few years ago by a previous bear-like visit? (I had decided that that earlier event was probably a bear, as the plastic trash barrel had suffered several puncture holes—about the size of what a bear claw would leave.)

I gingerly and silently stepped outside, to see if Bruno was still around—keeping close to the door, in case a hasty retreat was in order. Bears are not aggressive critters, I believe, but I did not wish to test this one's tranquility. It seemed to be gone. The next morning, as I checked out the area, I could spot no damage.

My wife did some internet investigation the next day. Bears forage for food in early morning or at twilight—that defines them as crepuscular critters. They are omnivorous, feeding on most anything they encounter. Virginia black bears are shy and rarely belligerent. (Maybe I could have wandered farther from the door, the previous evening?) Their territory is very large—being up to 20 square miles for a female and as much as 100 square miles for a male. Roaming around that expansive range is likely why we've never seen one before. Maybe it'll make the rounds back to our yard in another 34 years. If I'm alive at 111, I'll be ready for that visit.


Friday, June 8, 2018

Big Mouth


We caught this black snake in the process of swallowing a goldfinch. How does it manage to open its mouth so much? Click to enlarge.

Thursday, May 31, 2018

Scrutinizing Skepticism—Part 2

So some degree of skepticism and discernment can be very useful to us. You can hear, from time to time, public school officials talk about teaching children the skills of “critical thinking,” of helping kids to become discerning young people. They usually mean teaching children to think for themselves, to be judicious, aware, observant. That sounds nice, but in fact that is quite different from what most public schools actually do; they encourage just one way of considering things (dogma), promote complete acceptance of authority, and then test students in a manner that inculcates in them the belief that they are either right or wrong in response to questions (that is, there are no shades of gray or even alternative viewpoints to the authorized one). That's not critical thinking.

Considering the arguments above, it seems to me that they offer an explanation of why certain segments of society—most often the pious and faithful—have traditionally disapproved of skeptics: skeptical ideas and doubt can threaten their beliefs. 
 
In fact, throughout history, neither the state nor religious people have been sympathetic to skeptics, because they cast doubt on society's beliefs. Especially in America, where the state and Christianity hold many of the same convictions, skepticism is often not welcome—sometimes along with its cohorts, discernment and critical thinking. At least we have not yet come to the point where we methodically jail skeptics, as they do in Turkey and China.

I believe there is another kind of person who also thinks skeptically, as well as discerningly; they are called prophets. Throughout history prophets have doubted and questioned the beliefs and behavior of mainstream society. When they've spoken up about their views and challenged orthodoxy, they've often become even less popular than skeptics.

Furthermore, I also think that a historian can benefit from a good dose of skepticism. My favorite historian for several years now is Yuval Noah Harari, who teaches history at Hebrew University in Israel and has written two profound books: Sapiens and Homo Deus. (In fact, I discovered Harari in a MOOC he taught several years ago.) Harari examines history through the eyes of a skeptic. He's both discerning and a very clear thinker. Years of lengthy meditation retreats have sharpened his mind. His particular strength is to examine history, connect the dots, and then interpret current events with that knowledge. That's the nature of his first book (Sapiens) listed above. He then goes on in the second book (Homo Deus) to connect the dots of today's events and then project what the future will be like.

So, I believe skepticism and a dose of doubt offers me some valuable thoughts on how to perceive the world around me. Healthy doubt can be useful—especially when coupled with careful examination of that world, and furthered by a good dose of curiosity. I can become a skeptic, without having to become a card-carrying atheist, or without denying the possibility of possessing any kind of knowledge; because skepticism is not necessarily about distrust or being a heretic. It's just as much about curious inquiry and discernment. So let those kids in school be taught critical thinking. Maybe they'll even grow up to become moderate skeptics





Wednesday, May 23, 2018

Namaste Gnome

I am building this sculpture, which I call my "Namaste Gnome," out of concrete block overlaid with strong mortar. It's almost completed. He's about four feet (1.2 m) tall. Click to enlarge.

Thursday, May 17, 2018

Scrutinizing Skepticism—Part 1

I am currently taking a MOOC (Massive Online Open Course) on skepticism from a Dutch university. It is a topic that has interested me for a long time, but as yet have not delved into. Although I sometimes have felt attracted to skepticism, I also know that it has often been a controversial issue throughout history, so there's a bit of a stigma attached to it that has caused me to hesitate about exploring it further. I'm also aware that skepticism is a very complex and broad topic, so I realize that I've known too little about it. Hence, when I saw this MOOC, I signed up.

Before going further, let me define skepticism, so it's clear what the topic of this blog is, since skepticism is so broad, as well as being controversial. Some people have even vehemently opposed it. My dictionary defines a skeptic as “a person inclined to question or doubt all accepted opinions.” As a prime example, many skeptics throughout modern history have questioned the beliefs of Christianity and other religions. As a result, Western skepticism has tussled with Christian dogma for several centuries. Thus, many Christians have viewed skeptics as unwelcome agnostics, if not actively opposing them as being atheists. Digging a little deeper in history, my dictionary defines an ancient skeptic as a “philosopher who denies the possibility of knowledge, or even rational belief, in any given sphere.” That's a pretty radical position!

The dictionary goes on to define being skeptical as “not easily convinced; having doubts or reservations.” Traditionally, skepticism is “the philosophy relating to the theory that certain knowledge is impossible.” The root of the word skepticism is the Greek word skeptikos, which is “inquiry” or “doubt.”

Thus, skepticism comes in various degrees—from modest doubt to firm disbelief in even the possibility of knowledge. So if I identify with skepticism, how mild or radical am I going to be? Am I doubtful of certain prevailing beliefs, or do I think that all knowledge is useless?

I have written before on this blog about the usefulness of having some degree of doubt about what we see and hear from the media and from statements made by others. Thus it seems to me that a modicum of doubt can be useful. In contrast, people who are gullible are, according to the dictionary, “easily persuaded to believe something; they are easily fooled and deceived.” In today's environment, there is so much false information coursing through the internet and other media, that one needs some discernment sprinkled with a modest dose of doubt, in order to avoid being gullible and naive.

More on skepticism next time...