For Science: Neil deGrasse Tyson’s “Death by Black Hole”

Death By Black Hole

Death by Black Hole is an epic read. What makes this stand out from the average science essay collection is Neil deGrasse Tyson’s unwavering expertise in combination with his remarkably down-to-Earth explanations of not only how things happen, but also of how we discovered how things happen.

For instance, everyone today knows there is a constant speed of light, and we actually encounter it, sometimes in latency in the Internet. But as far as our intuition goes, light moves infinitely fast, i.e. it is instantaneous. In fact, I still remember Bill Nye the Science Guy trying to outrun a beam of light in his show. After many tries, he was never able to succeed.

Tyson reveals to us that even Galileo, in 1638, thought that light was instantaneous, when his lantern experiment failed to yield a measurable delay. It was not until Ole Rømer who first saw and interpreted correctly the evidence that light is not instant. In “Speed Limits”:

Years of observations had shown that, for Io, the average duration of one orbit—an easily timed interval from the moon’s disappearance behind Jupiter, through its re-emergence, to the beginning of its next disappearance—was just about forty-two and a half hours. What Rømer discovered was that when Earth was closest to Jupiter, Io disappeared about eleven minutes earlier than expected, and when Earth was farthest from Jupiter, Io disappeared about eleven minutes later.

Rømer reasoned that Io’s orbital behavior was not likely to be influenced by the position of Earth relative to Jupiter, and so surely the speed of light was to blame for any unexpected variations. The twenty-two-minute range must correspond to the time needed for light to travel across the diameter of Earth’s orbit. From that assumption, Rømer derived a speed of light of about 130,000 miles a second. That’s within 30 percent of the correct answer—not bad for a first-ever estimate…. (p. 120)

That someone deduced the speed of light with 1600’s technology is remarkable.

In addition, Tyson enlightens us with the exciting information we all want to know. Antimatter, for instance, annihilates on contact with normal matter, releasing tremendous amount s of energy. In Dan Brown’s Angels and Demons, a tiny vial of antimatter explodes with the violence of a nuclear bomb. But what if a Sun made out of antimatter collided with our own Sun? How big would the blast be? According to Tyson in “Antimatter Matters,” the explosion would be frighteningly large:

If a single antistar annihilated with a single ordinary star, then the conversion of matter to gamma-ray energy would be swift and total. Two stars with masses similar to that of the Sun (each with about 1057 particles) would be so luminous that the colliding system would temporarily outproduce all the energy of all the stars of a hundred million galaxies. (p. 106)

While this anthology is comprised of essays which are all distinct and divided into categories, it is still possible enough to read it like a normal book from start to finish if you are a science enthusiast.

However, given the sheer variety of different topics, there are wide jumps of topics and some overlap of subject material between essays that might alienate a some readers. This was not too much of an issue for me, but I did find the lack of an overall thesis sort of strange, and this this forced me to read it in a different manner than for most books. For someone interested in a popular book on astrophysics that was originally intended as a book, I would highly recommend Michio Kaku’s Physics of the Impossible, which is more coherent and packs more punch than Death by Black Hole.

This is not to say that Death by Black Hole is without merit. It is one of the few books to explain not just the contents of scientific discoveries, but also the discovery process itself, which can oftentimes be more fascinating to learn about than the results. Neil deGrasse Tyson is one of the finest communicators of science in our time, and I always find his talks on YouTube fascinating. As an essay collection on science, Death by Black Hole is unmatched.

Are We in a Simulation? A Scientific Test

According to a recent article, scientists are planning a test to determine whether our universe is a computer simulation. This is pretty relevant to my blog as I have discussed this idea a number of times before [1] [2] [3] [4].

Soft Watch at the Moment of First Explosion

Of course, the must-read paper on this subject is philosopher Nick Bostrom’s article, “Are You Living in a Computer Simulation?” The implication, given a couple of premises, is that we are almost certainly living in a computer simulation. Not only that, but the argument posits that our simulators are themselves extremely likely to be in a simulation, and those simulators are likely too to be in a simulation, etc.

Indeed, how will scientists test for signs of a simulation?

“Currently, computer simulations are decades away from creating even a primitive working model of the universe. In fact, scientists are able to accurately model only a 100 trillionth of a metre, with work to create a model of a full human being still out of reach.”

spiral_galaxy

Even so, there are limitations beyond technical ones that should be considered. If a test does not find any evidence of our being in a simulation, that does not rule out the possibility—in fact, a very well-designed simulation would be very difficult, if not actually impossible, to tell apart from a “reality” to its inhabitants.

Conversely, suppose a test that did find “evidence” that we are in a simulation. How would we judge this evidence? How can we know which way the evidence is supposed to point? After all, even if we find “glitches,” they could turn out to be part of a larger set of natural laws.

As Richard Feynman once thought, suppose we are observing a chess game but are not told what the rules are. After looking at various snapshots of a game, we can piece together some of the rules, and eventually we will learn that a Bishop must stay on the same color when it moves. But one snapshot later, we find that the only Bishop in the game is now on a different colored square. There would be no way of knowing, without looking at many more games, that there is a rule where a Pawn can promote into another piece, such as a Bishop, and that the old Bishop was captured. Without this knowledge, we might have thought that the Bishop changing color was a glitch.

Now back to the article.

“By testing the behaviour of cosmic rays on underlying ‘lattice’ frameworks governing rules of physics that could exist in future models of the universe, the researchers could find patterns that could point to a simulation.”

Many disciplines would have to come together here to prove something fundamentally “wrong” with our universe. It would be the junction point of computer science, physics, philosophy, mathematics, neuroscience, astronomy.

The plan given in the article is a noble one, but I do not expect it to grant any important experimental data soon. Rather, it is the tip of an immense iceberg that will be explored in not years or decades, but millennia to come.

Two Important Principles

There are many principles that guide our philosophies, our thought, our reason, and even our morality. Two of the most important ones for me are the Cosmological Principle and the Anthropic Principle. Despite their opposite-sounding names, they are not mutually exclusive!

The Cosmological Principle

It can be phrased many ways, with many different connotations. The essence of the principle is that, when viewed from a larger perspective, Earth is not special within the universe. More specifically, it states that the laws of physics govern equally and universally, with no preference for any particular region within it.

To believe such a thing in ancient times was considered heretical. After all, almost all old religion positioned the Earth as the center of the universe, at least metaphorically if not physically. But the more we learned about the universe, the more we learned the fact that we are not at the center of the universe, the perhaps painful fact that we are not special. A frightening fact indeed.

In 2006, the Cassini spacecraft took a picture where Saturn eclipsed the Sun. There was a little dot in one area. At first you might think it is just one of Saturn’s moons, or perhaps a stray asteroid. Surely that can’t be anything we call special, right?

That dot turns out to be the Earth entire.

Now, on to the second rule.

The Anthropic Principle

Only those universes with the conditions to have life would be observed by such life from within. Therefore, given that we are observing our own universe from within, our universe must have sufficient conditions for life. That is to say, just for having life, our universe is not special.

With a multiverse, there may be billions, trillions, and possibly even infinitely many universes. Even if only a tiny fraction of universes support life, the anthropic principle shows that given we can observe our own universe, we are automatically in that tiny fraction.

After all, if our universe could not support life, then we cannot exist within it. So, there would be nobody in that universe to realize it cannot support life. Someone who has studied conditional probability should be able to understand this. While the chance that a universe supports life might only be 0.01% (i.e., our universe is “fine-tuned”), the chance that our universe supports life is 100% regardless, because we are already here to make the observation in the first place.

The anthropic principle says that our universe is not special, while the cosmological principle says that Earth is not special within the universe. As humans, we cannot afford to satisfy ourselves with Earth, merely one of the billions of billions of rocks in the universe. Rather, it is imperative to explore the universe and understand its mysteries.

Science Exaggeration in the Media

Recently, new scientific data showed that the Sun is rounder than previously thought. As readers of this blog probably know, I am a very fact-oriented person and I dislike exaggeration, especially regarding scientific data.

Let’s see how the media decided to label this discovery, just looking at the titles of a few articles…

Doing it right:

  • Huffington Post –  “Sun’s Shape: NASA Data Show Our Star More Round Than Previously Thought”
  • Complex Tech – “Scientists Discover the Sun is Rounder, Flatter Than Previously Thought”
  • Gizmodo (UK) – “Turns Out The Sun Is Rounder And Flatter Than We Thought”

Doing it wrong:

  • Gizmodo (US) – “We Were Totally Wrong About the Sun’s Shape Until Yesterday”
  • Yahoo! – “Astronomers continue to be baffled by Sun’s nearly perfect shape”
  • The Independent – “Sun is too round, say scientists”
  • Herald – “Mystery of our too-round sun”
  • The Christian Science Monitor – “Mystery continues: Why is the sun ‘too round’? New measurements show the shape of our sun is ‘too round’ to match the theories about the forces at work on the sun.”

Want to know the really interesting part?

The article in the Huffington Post link and The Christian Science Monitor link are the exact same article by Charles Q. Choi, frequent contributor to Scientific American. Funny how different news agencies manage to spin the same story with a different title.

Curiouser and Curiouser

The wait is almost over. Check out NASA’s official page on the Curiosity rover.

The rover is currently closing in on Mars, with a few hours before landing. The image below links to NASA’s “Where is Curiosity” page with real-time locations.

The landing itself will be very intricate. Many different processes will have to work perfectly for a successful landing. Let’s hope all goes well.

Edit: It successfully landed! Great job NASA! Here is the first picture, in which Curiosity overlooks its own shadow: