Blockbuster Science

by David Siegel Bernstein

  Some social circles (they call themselves Whovians) claim that the asteroid that killed off the dinosaurs was sent by the transhuman Cybermen in an effort to destroy Earth. Doctor Who companion Adric tragically sacrifices himself in the attempt to save our planet. It didn't work for the dinos, but it worked out okay for mammals. For Adric haters, it was a complete success. I can nitpick this episode until tomorrow's breakfast, but the science of this Doctor Who episode makes more sense than that of Armageddon.

  THE SUN AND EARTH: A RELATIONSHIP THAT ENDS WHEN THE LIGHTS GO OUT

  Our sun is 4.5 billion years old. It is nearing the halfway point of its yellow phase where its energy predominately comes from fusing hydrogen into helium. We like this phase. It has been good for life on Earth. However, you should know one important thing. Although our sun appears yellow through our atmosphere (don't look at it unfiltered!), it is really white. The yellow wavelength travels all the way through the atmosphere while the blue wavelength is scattered (blue skies smilin’ at me, and all that). I'll call it a yellow star to avoid confusion.

  Now, don't get too comfortable thinking that human civilization has at least another 5.5 billion years before we must exit this planet as the sun goes into its red phase. Over the next two billion years, the sun will expand and grow hotter as it begins to run out of hydrogen to burn. Helium will look tastier and tastier as an energy choice.

  The increase in heat that will result will change Earth's carbon cycle. This will lead to more water vapor in the air and runaway greenhouse effects. We will be the new Venus on the block. If humans are still on the planet during this two-billion-year transition, they will hopefully have moved toward the poles or underground. At the very least, we would need to set up the solar shields described in chapter 11 to block out the rays.

  In about 5.5 billion years, as the ratio of helium to hydrogen fusion increases (ending its yellow phase), the sun will become red and bloat outward. The Goldilocks habitable zone will be pushed farther and farther outward. The sun will also become lighter. The drop in gravity will cause all the planetary orbits to widen. This is where the physics get really tricky, and by tricky I mean there is no consensus on the amount of mass that will be lost or the degree of orbital changes. Will our red giant sun expand far enough to engulf Earth, or will Earth's expanding orbit save it?

  It won't matter. At that point, it won't be habitable for human life. Earth is done with us. The atmosphere and oceans will have evaporated from the increased heat. But we already left, right? I bet that Saturn's moon Enceladus is looking pretty good right now. The temperature on Mars might not be too bad. I hope that before this era arrives, our geoengineers have read chapter 12 and worked on terraforming other locales in the solar system.

  The sun has one more set of fireworks to ignite. After about 150 million years performing as “Big Red,” it will run out of helium to burn. This will signal its final curtain call. It will shrink until helium from its outer regions pushes down on the core, ignites the outer layer, and blows it into space in clouds of gas and dust. The process will repeat until only the core remains.

  The core will continue to collapse for another 500,000 years. Eventually the sun enters its elderly phase and will be known as a white dwarf. No more fusion occurs, but it is still hot. Whatever is left of humanity can steer their asteroid colonies or self-contained VR servers close enough to stay warm and absorb energy to fuel their uploaded minds. This will work until the white dwarf fades to black over another (speculated) trillion years. After that? We had better have moved to other stars.

  WHY WILL ONLY SUPERSIZED GALAXIES EXIST IN THE FUTURE?

  The Milky Way galaxy is part of a gang made up of fifty-four galaxies. Astronomers came up with the intimidating name Local Group for these thugs. Most of the gang members are small, but the Milky Way is a big player along with the Andromeda and Triangulum galaxies.

  The Local Group is gravitationally bound, meaning that the gravity holding the members together is stronger than the universe's expansion. This will be true for a long time but not forever. Gravity will lose in the long run to the stretching (dark energy) of the expansion. As nonmember galaxies move away from Earth, the stars of the Local Group are actually getting closer.

  A rumor claims that the gang members don't always get along well. The word on the street is that in about four billion years, the Andromeda and Milky Way galaxies are going to clash.13 Yes, a collision is imminent. They will first pass through each other (our fading sun will be safe because stars aren't all that close to each other). Then, thanks to gravity, they will snap back toward each other.

  This will happen over and over until they combine into a single galaxy. And if the super massive black holes at the core of these galaxies collide as predicted, a lot of energy will be released as gravitational waves. Eventually, this galactic martini shaker will apply mixology between all fifty-four gang members until only a single super-galaxy that I shall now name DAVID is left. This naming is unofficial. I'm not authorized to name this new hybrid galaxy in the science world. But in the universe of this book, I am almighty.

  This process will happen to all local groups across the entire universe. All that will be left are super-galaxies separated due to expansion.

  WE CAME ALONG AT A GOOD TIME (TO PREDICT THE END OF THE UNIVERSE)

  We have evolved in the universe at a very fortunate time. It hasn't grown so big that we can't come up with really cool cosmological models that describe its origin and its future. Future civilizations might not be so lucky.

  If an intelligent race of beings evolved in one of the super-galaxies, what could they learn about the universe? More importantly, what could they learn of the DAVID system? Nothing, actually. They will not be able to see any other galaxies once the other super-galaxies have faded over the horizon faster than the speed of light. They won't know about DAVID.

  Their observational science will determine that theirs is the only galaxy in the universe. No evidence for an expanding universe or a big bang will exist. A large portion of our universal history is written in the cosmic background radiation (even more chapter 4 goodness), which at some point will have been stretched so thin it will become undetectable. This civilization will conclude that the universe is eternal and unchanging and that they are the only galaxy in it.

  THERMODYNAMICS WILL BE THE END OF US, BUT FIRST LEARN ITS LAWS

  As the prefix thermos- suggests, thermodynamics is the study of heat, and three laws govern this area. A zeroth law about temperature change kicks it off. Below is a description of the laws followed by an easy summary sentence to help you remember and understand the meaning of each.14

  0.If the temperature is higher in a system that comes into contact with another system, its temperature will fall while the temperature in the other system will rise until both temperatures are the same.

  Easy way to remember: there is a game and you must play.

  1.Energy and matter cannot be created or destroyed within a closed system. This law is called the law of conservation of energy.

  Easy way to remember: you can't win; you can only break even.

  2.The entropy of any closed system that is not in a thermal equilibrium will almost always increase. Thermal equilibrium means no temperature differences exist within the system. Entropy is the amount of a system's energy that is unavailable for work.

  Easy way to remember: you can't break even.

  3.Entropy in a closed system approaches a constant value as temperature approaches absolute zero. Absolute zero is the lowest temperature possible where movement of molecules has the least amount of kinetic energy (movement).

  Easy way to remember: you can't quit.

  Summary of thermodynamics: if you think things are a mess now, just wait.

  HOW DOES ENTROPY EXPLAIN THE DIRECTION OF TIME?

  From the second law of thermodynamics we derive entropy, the measure of disorder within an isolated system. Consider your bedroom. If you make no effort to clean it, it w
ill gradually become messier. Perhaps quicker for some than others. The only way to prevent the messiness is to regularly clean the room.

  In physics, the equivalent is to pump energy into a system. The addition of energy is the only way to slow down or reverse entropy. However, in an isolated system such as our universe, the first law of thermodynamics states that energy cannot be added, so entropy (disarray) will continue increasing. If no universal housekeeper pops in for a cleaning, everything everywhere will gradually fall into disarray.

  The earth avoids complete disarray because our sun pumps some of its energy into our system and pushes back against entropy. Unfortunately, the sun will eventually run out of energy.

  The general rise in entropy gives us a sequence of events physicists call the arrow of time. The arrow does not tell us that the past leads to the future. It only tells us that it goes from order to disorder. This is an important distinction. When entropy reaches its maximum value, the arrow of time will break.

  HOW IT ALL ENDS

  The first law sets us up for the fall. The law of conservation of energy ensures that the amount of mass and energy at the start of the universe remains constant throughout any point in its history or future. Thanks to the expansion, the universe is stretching out a fixed amount of matter. Eventually it will become so thin it will be as if it never existed. Thanks to dark energy, it will expand faster and faster. Matter and energy will thin out until at some point even individual atoms are pulled apart.

  The third law of thermodynamics makes the dire prediction of the universe's ultimate fate. In the far distant future as the universe veers toward disorder, there will be no more thermodynamic energy (it will have been stretched too thin). This doesn't mean heat won't be present but that heat differentials will no longer exist. A single universal temperature will rule. This is called the heat death of the universe.

  WHEN ALL THE SUNS TURN OUT THE LIGHTS

  All the stars will eventually run out of fuel. The main sequence stars described in chapter 15 will become white dwarfs. After that, they cool down into black dwarfs that will feed the massive black holes left in the universe. In a nonillion years, all that will be left are black holes. That's pretty far in the future. A nonillion is described in chapter 4.

  The black holes will try to feed on the tiniest bits of energy left, but the pickings will be slim, so they will begin to evaporate. Even the evaporated radiation isn't much to talk about. It will be stretched so thin that its energy (wavelength) will be negligible. The universe will get close to the absolute zero described by the third law of thermodynamics, the heat death with a broken arrow.

  The universe will be an unchanging, cold place with no energy or mass. There can be no life, mechanical or organic, because that requires atoms and energy. There will not even be enough energy for thought.

  LIFE AFTER THIS UNIVERSE

  Perhaps before the heat death, if the universe stretched enough, spacetime itself might tear into another dimension into which posthuman life might escape.15 Or perhaps much earlier, posthumans of a type VI civilization (chapter 6) decided to tour the multiverse (although the multiverse technically isn't science). Now, a type VII civilization might try to pump in energy from the universes they have created outside the universe. This would drive back the entropy.

  PARTING COMMENTS

  I know. Not a happy chapter. You shouldn't feel too despondent because a bit of good news can be found. Science has not excluded the possibility that some life-forms (or artificial intelligences) might survive until the end of the universe…or possibly outlive it!

  You might be the person to make it happen. I'm sure you could think up interesting and perhaps unexpected ways to combine the scientific ideas in this book. That's how much confidence I have in you. If you are not a scientist then perhaps you could use your ideas to create great science fiction or a cool video game.

  This kind of speculation drives scientists and creators of science fiction into the realm of Arthur C. Clarke's second law of prediction: the only way of discovering the limits of the possible is to venture a little way past them to the impossible.16

  Bye for now. There is a lot more science and science fiction to share in our universe.

  Somewhere in the hypothesized multiverse there may be an Earth where this book doesn't exist. A very sad Earth because we would never have gotten together to celebrate all things science and science fiction. So first up, I want to acknowledge you the reader for being in the correct universe. Thank you.

  Quantum mechanics has shown that not even space itself is a pure vacuum. Quantized field interactions are happening everywhere; this is what makes the universe such an interesting place. Yes, science has shown that nature really does abhor a vacuum. In the scaled-up universe, writers and scientists also shy away from working in a vacuum. It takes a team to do good science, and it takes a team to put together a good book. With that in mind, I want to begin with thanking Maryann Karinch, the agent who believed in my project from the beginning.

  I would also like to express my gratitude to the staff of Prometheus Books. They are an amazing group of people who helped make Blockbuster Science into something special. In particular, Jeffrey Curry, who read the manuscript (I can only guess how many times), offered suggestions, and helped me track down sources. Because of me, I suspect he can't stop from talking techno babble to his friends. Next up, Hanna Etu (we share a love of science fiction), who helped me through the publishing technicalities. And then there is the editor in chief, Steven L. Mitchell. He signed me up, believing in my idea of promoting science by linking it to science fiction. I know I annoyed him with my jokes, but he kept me around anyway. Thanks. I want to acknowledge the readers the Prometheus team found. They challenged me with science questions and which topics to expand on.

  A shout-out goes to my writer's group, Words-in-Progress. Trust me, the membership was never timid about telling me what didn't work. Of particular annoyance (I mean helpfulness) were Jim Kempner and Skip Seevers.

  I can't forget Laine Cunningham and her editing. She helped me see this project through to publication. Also, I need to shine a light on Leya Brown who helped me track down some of the illustrations.

  A special thank-you goes to Susanne Shay, whom I'd go to when I had trouble making a sentence work. She'd always agree: it didn't work. Then she'd pull out her tools and help me fix it.

  There is this kid named Seth Bernstein, who not only supported this book but also reminded me that Tony Stark is a cyborg because of his artificial heart. Stark's dressing up in an Iron Man suit to play with the Avengers is more of a personal choice. I made sure I got that correct in the book. Thanks, son. Speaking of my children, I want to thank Gwendolyn for being my number one fan. I know I have a repeat customer with her. I want to thank my wife, Michelle, for putting up with me during this project.

  Finally, I want to thank my father, Murray, for watching Doctor Who with me when I was a kid and taking me to see Star Wars. Because of that, this book is his fault.

  INTRODUCTION

  1. William Wilson, A Little Earnest Book upon a Great Old Subject (London: Darton, 1851).

  2. The philosopher and theologian William Whewell formally proposed the word “scientist” in 1840 in his work The Philosophy of the Inductive Sciences. “We need very much a name to describe a cultivator of science in general. I should incline to call him a Scientist.” Whewell was really into nouns. William Whewell, The Philosophy of the Inductive Sciences (London: John W. Parker, 1840), p. 113.

  3. Arthur C. Clarke, Report on Planet Three and Other Speculations (New York: Harper & Row, 1972).

  4. Arthur C. Clarke, Profiles of the Future: An Inquiry into the Limits of the Possible (New York: Popular Library, 1973).

  CHAPTER 1: ONCE UPON A SPACETIME

  1. Venture 49 (September 1957).

  2. Albert Einstein, trans. Robert W. Lawson, Relativity: The Special and General Theory (New York: Henry Holt, 1920).

  3. David Nield, “Physics
Explained: Here's Why the Speed of Light Is the Speed of Light,” Science Alert, April 13, 2017, https://www.sciencealert.com/why-is-the-speed-of-light-the-speed-of-light (accessed June 19, 2017).

  4. Joe Haldeman, Forever War (New York: St. Martin's Press, 1974).

  5. Orson Scott Card, Ender's Game (New York: Tom Doherty Associates, 1991).

  6. John Archibald Wheeler and Kenneth Ford, Geons, Black Holes, and Quantum Foam (New York: W.W. Norton, 2000), p. 235.

  7. Neil Ashby, “Relativity and the Global Positioning System,” Physics Today, May 2002.

  8. U.I. Uggerhøj, R.E. Mikkelsen, and J. Faye, “The Young Centre of the Earth,” European Journal of Physics 37, no. 3 (April 8, 2016).

  9. Tom Siegfried, “Einstein's Genius Changed Science's Perception of Gravity,” Science News, October 4, 2015, https://www.sciencenews.org/article/einsteins-genius-changed-sciences-perception-gravity (accessed 6/30/2017).

  10. A. Einstein and N. Rosen, “The Particle Problem in the General Theory of Relativity,” Physical Review 48, no. 1 (July 1, 1935): 73–77.

  11. Paige Daniels, “The Outpost,” in Brave New Girls: Tales of Girls and Gadgets, eds. Paige Daniels and Mary Fan (CreateSpace Independent Publishing Platform, 2015).

  12. Madeleine L'Engle, A Wrinkle in Time (New York: Farrar, Straus & Giroux, 1962).

  13. S. W. Hawking, Black Holes from Cosmic Strings (Cambridge: Cambridge University Press, 1987), p. 5. Published in Physics Letters, B231 (1989): 237.