A short history of nearly everything Read Online Free Page A

space as our puzzled flatlander, only we are flummoxed by a higher dimension.
    Just as there is no place where you can find the edge of the universe, so there is no place where you can stand at the center and say: “This is where it all began. This is the centermost point of it all.” We areall at the center of it all. Actually, we don’t know that for sure; we can’t prove it mathematically. Scientists just assume that we can’t really be the center of the universe—think what that would imply—but that the phenomenon must be the same for all observers in all places. Still, we don’t actually know.
    For us, the universe goes only as far as light has traveled in the billions of years since the universe was formed. This visible universe—the universe we know and can talk about—is a million million million million (that’s 1,000,000,000,000,000,000,000,000) miles across. But according to most theories the universe at large—the meta-universe, as it is sometimes called—is vastly roomier still. According to Rees, the number of light-years to the edge of this larger, unseen universe would be written not “with ten zeroes, not even with a hundred, but with millions.” In short, there’s more space than you can imagine already without going to the trouble of trying to envision some additional beyond.
    For a long time the Big Bang theory had one gaping hole that troubled a lot of people—namely that it couldn’t begin to explain how we got here. Although 98 percent of all the matter that exists was created with the Big Bang, that matter consisted exclusively of light gases: the helium, hydrogen, and lithium that we mentioned earlier. Not one particle of the heavy stuff so vital to our own being—carbon, nitrogen, oxygen, and all the rest—emerged from the gaseous brew of creation. But—and here’s the troubling point—to forge these heavy elements, you need the kind of heat and energy of a Big Bang. Yet there has been only one Big Bang and it didn’t produce them.So where did they come from?
    Interestingly, the man who found the answer to that question was a cosmologist who heartily despised the Big Bang as a theory and coined the term “Big Bang” sarcastically, as a way of mocking it. We’ll get to him shortly, but before we turn to the question of how we got here, it might be worth taking a few minutes to consider just where exactly “here” is.
     

A Short History of Nearly Everything

CHAPTER 2: WELCOME TO THE SOLAR SYSTEM
    ASTRONOMERS THESE DAYS can do the most amazing things. If someone struck a match on the Moon, they could spot the flare. From the tiniest throbs and wobbles of distant stars they can infer the size and character and even potential habitability of planets much too remote to be seen—planets so distant that it would take us half a million years in a spaceship to get there. With their radio telescopes they can capture wisps of radiation so preposterously faint that thetotal amount of energy collected from outside the solar system by all of them together since collecting began (in 1951) is “less than the energy of a single snowflake striking the ground,” in the words of Carl Sagan.
    In short, there isn’t a great deal that goes on in the universe that astronomers can’t find when they have a mind to. Which is why it is all the more remarkable to reflect that until 1978 no one had ever noticed that Pluto has a moon. In the summer of that year, a young astronomer named James Christy at the U.S. Naval Observatory in Flagstaff, Arizona, was making a routine examination of photographic images of Pluto when he saw that there was something there—something blurry and uncertain but definitely other than Pluto. Consulting a colleague named Robert Harrington, he concluded that what he was looking at was a moon. And it wasn’t just any moon. Relative to the planet, it was the biggest moon in the solar system.
    This was actually something of a blow to Pluto’s status as a planet, which had never been terribly robust