I am an atheist. I believe that the universe in all its complexity is a found object—that its being does not require a supernatural creator to design it, as if it were a human handiwork. I also believe that the universe functions well as a complex expression of energy and matter—that its continued existence does not require a supernatural caretaker, as if it were some palatial estate or business enterprise.1 I also believe that human beings, rather than some kind of flawed angel, or a parasite on the Earth, are the best thing going within at least a couple of parsecs of here. However, I try to keep an open mind.
I believe humans now know enough science to begin making a first-order approximation of how the universe came into being, to explain the origins and nature of the planets, of life, and of human consciousness. What do I mean by “first-order approximation”? Well, something like “first wrong answer, but still pretty close.”
For example, I take exception to the Big Bang as a creation story. A universe that originated in a pinpoint of infinitely dense, infinitely hot matter was the first answer to Edwin Hubble’s observed red shift in the light from distant galaxies. If the energy of that distant starlight is decreasing in proportion to the distance between its origin and us, then according to Big Bang theorists, the fall-off must be due to a Doppler effect as those galaxies recede from us. And if those galaxies are receding, then where did they and all the matter in the universe start from? Why, from some kind of explosion of a single hot, dense point right around here.
Some evidence supports the Big Bang, like the discovery of the cosmic microwave background, presumed to be the original energy fallout from that explosion, which has cooled and stretched as the universe expanded. And some evidence disputes it, like the nature of the universe we can see today. That is, the universe we have is flat, homogeneous, and isotropic—or, in English, pretty much the same all over and in every direction we look. That’s not what you’d expect given that the universe has been expanding steadily like a bomb blast for all time and should be highly curved and heterogeneous—that is, not really the same here as it appears to be over there.
To fix that little problem, cosmologist Alan Guth came up with the theory of inflation. That is, at some early point between BANG and today’s ever-expanding residue, the universe and all its matter accelerated at incredible speed, even greater than lightspeed, and this allowed the universe to become homogenized and develop the structure we see today.
Uh-huh. While according to some theories of physics nothing can move faster than the speed of light, according to this theory of physics, at some point in the distant past everything was moving faster than the speed of light.2 So I’m going to add light, its exact nature, and the effects of its speed to the number of things we just don’t understand yet.3
The universe that we can observe defies common sense when we try to understand it. Not only does our current creation myth, the Big Bang, require the universe to accelerate faster than light, but the study of physics requires other oddities.
Black holes, for one. We now understand that the universe is riddled with them. A black hole apparently lies at the heart of every galaxy. According to theory, the universe should contain more than galaxy-size black holes and black holes as a residue from the expiration of massive stars. The original roil of that Big Bang should have created myriads4 of micro black holes—masses the size of mountains compressed to points with event horizons smaller than a proton. These would be swarms of dangerous little entities—but we just don’t find them anywhere.5
To explain this failure of theory, cosmologist Stephen Hawking posited that the simultaneous creation and destruction of virtual matter and antimatter particles in empty space caused the micro black holes to evaporate long ago. Now, in theory, nothing can ever leave a black hole, because its escape velocity is greater than the speed of light. But if a virtual matter/antimatter pair pops into existence right at the event horizon, and if one of the paired particles falls into the hole, then it robs the hole of energy potential while its partner emerges as a real particle. If this happens often enough—and in dealing with virtual particles and virtual events, the mathematics of probability allow you to imagine as many as you like occurring wherever you like—then the black hole eventually evaporates.
Uh-huh. Why not just say that the pixies have eaten up all the black holes?
My favorite example of physicists playing with common sense has to do with the dimensions of empty space. Presumably, the mathematics of Einstein’s relativity and the mathematics of quantum mechanics cannot be reconciled in three dimensions of space plus time. However, everything buttons up nicely if space is shown to have a fourth physical dimension—which we cannot see, touch, or understand. Now the proponents of string theory, to make their beautiful mathematics work, need even more dimensions that we don’t directly experience.
String theory supposes that the garden variety particles of quantum mechanics—hard little points of matter like quarks and electrons, gluons and muons, and all the rest—are not actually isolated bits of solid stuff but instead tiny loops of string that vibrate like the strings of a guitar. The energy with which they vibrate, fast or slow, defines their relative size, spin, and other characteristics of quarks, muons, and so on. It’s a really elegant idea. Except that in addition to the three dimensions we know about—x, y, and z—string theory mathematically requires eight more dimensions operating down at the level of the subatomic where, if they exist at all, we don’t happen to stumble over them in everyday life.
I’m not a foe of mathematics, although I was trained in language and literature instead of numbers and mathematics. But I do note that math is as much a product of the human brain trying to fit our imaginations to the observable universe as the word choices of any poet.6 Mathematics is an elegant and useful system, but there are parts of it—consider imaginary numbers, which cannot exist within the rules of the system—that defy common sense.
I don’t require the universe or our response to it to be entirely common-sensical. Good heavens, we’re not Vulcans. We can exercise some imagination. But as noted above, I like to keep an open mind. And I dislike playing favorites.
So my question is this: Why is it acceptable in physics, cosmology, and mathematics—the hard core of our sciences—to create unbelievable and untestable hypotheses, but not in other realms of human thinking? If a scientist can legitimately be asked to believe, to take on faith, the existence and propriety of a universe that flies faster than the speed of light, of depthless black holes that evaporate in the presence of virtual particles which cannot be measured or detected, and of multiple dimensions that operate undetectably below the level of everyday experience—so long as these propositions can be justified through the acrobatics of mathematical proofs—then why must the existence of gods, angels, spirits, sprites, and other unseen beings and forces be ruled out of bounds? Because they don’t play by the rules of mathematics? Because they don’t exist in the realm and curriculum of science?
Science—the word according to its Latin root scire, meaning “to know”—draws its authority mostly from the flowering of reason during the 17th and 18th centuries, the European Enlightenment. Science became a trusted way of looking at the world when deep thinkers worked out the “scientific method.” This is a system for observing reality, posing questions about those observations, predicting outcomes, and testing them through experimentation. People trusted science because it offered logical proof. It didn’t always fit within the framework of what people at the time called “common sense”—for who could believe some of its propositions? That the Sun, which demonstrably rose in the east and set in the west, wasn’t actually orbiting the Earth. That a lightning bolt striking down out of the sky was the same thing as the little tingle you get from shuffling across the carpet? Or that this invisible fluid would one day drive thinking machines and send information from one side of the planet to the other? But still, wherever science and its unique way of looking at the world were applied, it worked.
Yet my intuition tells me that today we’re operating at the outer edges of science. Mathematics and human imagination are building bridges into the unknown: particles that act like waves and waves like particles, forces that are sometimes particles and sometimes fields, virtual particles, dark matter, dark energy. I understand that these words are metaphors. That the photon is neither a particle like a grain of sand nor a wave like those that wash upon the shore but, instead, something different that merely has particle-like and wave-like qualities. I get it. And I also get that mathematics is a language only in metaphor, and that it expresses understanding that cannot be put into slippery English words.7
But ultimately, we must get back to the testing part of observation and hypothesis. With phenomena like the Big Bang’s residual evidence in red shifts and background radiation, or like the nature and lifestyle of black holes, or like the real substrate of that thing we call “matter,” I sense we are facing unknowns and spinning theories and mathematical constructs which cannot, of themselves, be tested.
It might be simpler to say, “God made them to be a puzzlement, and humans cannot understand them.” Except … except that I think we will one day understand them. We’ve just started with the first wrong answer. We’ve got a bit more—maybe a whole lot more—thinking and experimenting to do before we get to the final right answer. Or to the series of answers that will eventually lead to final understanding.
1. Of course, I allow that my atheism on these terms may be avoiding the question of first principles. The universe seems to have developed and continues its existence according to consistent laws that humans are still trying to work out, including those governing gravity, energy exchanges, the structure of matter, and time. Whether those laws, ensuring the consistency of the universe within its complexity, are a matter of design or just another set of found objects is a deep question. We can all imagine a universe that works differently. For example, any chemistry student could sit down and in fifteen minutes redesign the atom’s arrangement of electron shells so as to yield a wholly new kind of chemistry. Any genetics student could redesign DNA so as to yield a new kind of life. Is that to say that Someone had to pick the shape of the universe we actually inhabit and the interactions that occur within it? I try to keep an open mind.
2. Of course, according to Einstein’s relativity, physical matter moving at the speed of light experiences a vast increase in its mass. That’s not much of a problem if we’re dealing with all the material in the universe which has just escaped a single point of infinite density. Time also freezes for any matter that travels at superluminary speeds—but only for an observer in a frame of reference outside that matter. If you travel at the speed of light yourself, anyone observing you sees a person frozen in mid-gesture. But for you, time and your experience of it go on as before. Again, not much of a problem in a universe whose entire contents are boosted beyond lightspeed and there’s no other frame of reference to consider.
3. See the blog entries titled “Three Things We Don’t Know About Physics” from December 30, 2012 and January 6, 2013. According to these blogs, the three things are gravity, space, and time.
4. The word “myriad” comes from Greek and means either “countless” or, in its plural form, “ten thousand.” I suppose to a nation of shepherds and fishermen, 10,000 was an incredibly large number, equivalent to being countless. I remember, too, that the Persian Immortals, elite guard of the King of Kings, were supposed to number 10,000. They were “immortal” because, no matter how many you killed in battle one day, that night the king promoted the nation’s next-best fighters to make up their ranks. So the next day you were facing 10,000 fighters again. Immortal and, for all practical purposes, numberless.
5. I made use of a micro black hole in my first science fiction novel, The Doomsday Effect.
6. See the blog entries titled “Fun with Numbers” from September 19, 2010 and September 26, 2010.
7. But I also know that you can say ridiculous things with the language of mathematics, just as you can write grammatically correct but factually stupefying sentences in English. You can mathematically relate properties, measure correlations, and compare quantities that have no common-sense relationship in the real world. Mathematical formulas and computer models are only tools to aid in thinking—merely extended metaphors—and not, in and of themselves, proof of anything.
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