Dispatches from Planet 3
Page 19
Hawking at Cambridge University saw such an effect in his own work on quantum cosmology. To arrive at this conclusion Hawking first had to circumvent the unique and complicated status of time in the space-time continuum. While time can be considered a fourth dimension, it is very different from length, width, and height. In space an object can move freely in any direction—but in time an object must always move forward into the future and away from the past. And this requirement makes the mathematics of quantum cosmology quite complicated. The equations are tough to handle. Hawking decided to get rid of this restriction by treating time as just another dimension of space—a mathematical procedure (trick may be too strong a word) physicists often use to simplify what would otherwise be an intractable problem. The equation has been altered, but its solution can sometimes provide an inkling of the answer hidden in the more complicated equation. In the 1930s, quantum theorists used a similar approach to figure out how radioactive elements can eject subatomic particles. By all the classical laws of physics, the protons and neutrons within an atom don’t have enough energy to break free from the steely grip of an atomic nucleus. But physicists keenly grasped that, in the probabilistic world of the atom, there were small but real odds that a particle could acquire enough energy every once in a while to “tunnel” through its nuclear barriers and fly out of the atom.
Hawking’s foray into that nebulous realm where general relativity meets quantum mechanics suggested that time, nonexistent at first, could have emerged in an analogous fashion, burrowing into the real world from a domain of timelessness. Thus, there is no reason to inquire what came before the Big Bang. To Hawking, that was as senseless a question as asking what is north of the North Pole.
There’s another way to look at Hawking’s result: Time simply loses all meaning as you travel back, closer and closer to the Big Bang singularity, akin to the way a compass starts gyrating and loses its ability to indicate a precise direction as you near the north or south magnetic pole. A compass is useful only when it’s far from a magnetic pole; likewise, time may be discernible only after you get far enough away from the Big Bang singularity. Perhaps St. Augustine got it right when he wrote, in the fifth century, that “the world was made, not in time, but simultaneously with time.”
Unfortunately, St. Augustine did not reveal by what means, and that is the mystery that is so vexing. Hawking’s mathematical procedure offered a glimpse, not a final solution. Physicists as yet only recognize the problem, and sense what must happen, but are far from postulating a definitive mechanism. That awaits a full theory of quantum gravity.
Quantum gravity theorists like to compare themselves to archeologists. Each investigator is digging away at a different site, finding a separate artifact of some vast subterranean city. The full extent of the find is not yet realized. What theorists desperately need are data, experimental evidence that could help them decide between the different approaches.
It seems an impossible task, one that would appear to require re-creating the hellish conditions of the Big Bang. But not necessarily. For instance, future generations of “gravity-wave telescopes,” instruments that detect ripples in the rubberlike mat of space-time, might someday sense the Big Bang’s reverberating thunder, relics from the instant of creation when the force of gravity first emerged. Such waves could provide vital clues to the nature of space and time.
“We wouldn’t have believed just [decades] ago that it would be possible to say what happened in the first ten minutes of the Big Bang,” points out Kuchař. “But we can now do that by looking at the abundances of the elements. Perhaps if we understand physics on the Planck scale well enough, we’ll be able to search for certain consequences—remnants—that are observable today.” If found, such evidence would bring us the closest ever to our origins and possibly allow us to perceive at last how space and time came to well up out of nothingness some 14 billion years ago.
Notes
CHAPTER 1. EARTH IS BUT A SPECK
This chapter was first published in the Washington Post, Bartusiak (July 2009d).
CHAPTER 2. BEDAZZLED BY A COMET
nine times in the past three centuries: Rao (2012).
“that the Soul of Caesar”: Secundus (1847–48), p. 65.
“the most difficult of the whole book”: Newton (1999), p. 270.
first comet to be discovered with a telescope: Levy (1998), p. 12.
“comets are a kind of planet”: Newton (1999), p. 895.
“solid, compact, fixed, and durable”: Ibid., p. 918.
“extremely thin vapor”: Ibid., p. 919.
suggested that threads of magnetic force: Discussed in Kepler (1995).
planets carried around like leaves: Discussed in Descartes (1998).
“I have not as yet been able to deduce”: Newton (1999), p. 943.
“The space between the Sun and the fixed stars”: Halley (1705), p. 20.
“I dare venture to foretell”: Ibid., p. 22.
The comet appeared on schedule: Levy (2003), p. 26.
CHAPTER 3. TO BE . . . OR NOT TO BE A PLANET
They looked for five years: Bartusiak (1996), pp. 46, 49.
proposed . . . by, among others, the Dutch-American astronomer Gerard P. Kuiper: Jewitt (n.d.).
“The confirmation of the Kuiper belt changes our perception”: Bartusiak (1996), p. 50.
Michael E. Brown announced in 2005: Brown, Trujillo, and Rabinowitz (2005).
dubbed Eris: Brown and Schaller (2007).
Pluto was demoted: Overbye (2006).
astronomers sought an underlying pattern: Littmann (1988), p. 14, and Hoskin (1999), pp. 158–59.
The pattern from Bode’s On the New Eighth Major Planet (table): “Bode and Piazzi” (1929).
“Can one believe that the Creator of the Universe”: Hoskin (1999), p. 159.
jokingly referred to itself as the “celestial police”: Ibid., p. 160.
“The light was a little faint, and of the color of Jupiter”: Piazzi (1801). Also in Bartusiak (2004), p. 151.
“Since its movement is so slow”: Abetti (1974), p. 592.
Carl Friedrich Gauss was able to calculate its orbit: Littman (1988), p. 19.
“Piazzi had, indeed, here discovered a very extraordinary object”: “Bode and Piazzi” (1929), p. 182. Also in Bartusiak (2004), p. 151.
Ceres was smaller than our Moon: Herschel (1802).
he suggested the name asteroid: Ibid., p. 228.
Today it is known they are a field of debris: Hoskin (1999), p. 162.
CHAPTER 4. THE WATERY ALLURE OF MARS
Mars-shattering, discovery: Jerolmack (2013) and Williams et al. (2013).
strengthen the case that liquid water once flowed freely: Jerolmack (2013), p. 1056.
He was one of the Boston Brahmins: Strauss (2001), p. 3.
“After lying dormant for many years”: Lowell (1935), p. 5.
“is not without a considerable atmosphere”: Herschel (1784), p. 273.
“Considerable variations observed in the network of waterways”: Pannekoek (1989), p. 378.
adding 116 waterways to Schiaparelli’s original depiction: Lane (2006), p. 199.
“a trial to sane astronomers”: Sheehan (1996), p. 132.
“the surface of Mars was (and still is) notoriously difficult to make out”: Lane (2006), p. 201.
a few dark markings were seen: Ibid., p. 205.
news story of the year: “Mars” (1907).
CHAPTER 5. RINGS, RINGS, RINGS
due to the transit of a giant ringed planet: See Kenworthy and Mamajek (2015).
“very strange wonder”: Van Helden (1974), p. 105.
“The star of Saturn is not a single star”: Ibid.
“in three minor knots divided”: Hall (2014), p. 1318.
“a strange metamorphosis”: Deiss and Nebel (1998), p. 216.
“Saturn deceives or really mocks”: Van Helden (1974), p. 108.
Saturn looked as if it had handles: Ibid., p. 110.
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br /> “the problem of Saturn’s appearances had become a celebrated puzzle”: Ibid., p. 115.
“arms extended on both sides”: “Classics of Science” (1929), p. 191.
these arms had vanished altogether: Van Helden (1974), p. 120.
“surrounded by a thin flat ring”: Pollack (1975), p. 3.
“pure fiction”: Brashear (1999).
solid structure would be highly unstable: Pollack (1975), p. 4.
In a prize-winning 1856 essay: Maxwell (1859).
And that’s exactly what Keeler measured: Osterbrock (2002), pp. 158–64; Keeler (1895).
CHAPTER 6. THE BAFFLING WHITE DWARF STAR
had enough data to announce that Sirius and Procyon were not traveling smoothly: Bessel (1844).
completed one orbit every fifty years: Ibid., p. 139.
“The subject . . . seems to me so important”: Ibid., p. 136.
and thus lost in the glare: Holberg and Wesemael (2007), p. 167.
“there might have been a [prearranged] connection”: Welther (1987).
“It remains to be seen”: Bond (1862), p. 287.
Clark in 1862 garnered the prestigious Lalande Prize: Holberg and Wesemael (2007), pp. 170–71.
Russell doubted that such a classification could be correct: Holberg (2007), p. 114.
Walter Adams at the Mount Wilson Observatory in California confirmed the spectrum: Adams (1915).
“I was flabbergasted”: Philip and DeVorkin (1977).
“The message of the companion of Sirius”: Eddington (1927), p. 50.
British theorist Ralph Fowler finally figured out: Fowler (1926).
“star of large mass . . . cannot pass into the white-dwarf stage”: Chandrasekhar (1934), p. 377.
“there should be a law of nature”: “Meeting of the Royal Astronomical Society” (1935), p. 38.
“continued gravitational contraction:” Oppenheimer and Snyder (1939).
“Only its gravitational field persists”: Ibid., p. 456.
CHAPTER 7. THE STAR NO BIGGER THAN A CITY
“No event in radio astronomy seemed more astonishing”: Hey (1973), p. 139.
his calculations indicated that the dwarf would undergo further stellar collapse: Chandrasekhar (1931).
in a spectacular stellar explosion they had christened a “supernova”: Baade and Zwicky (1934b), p. 254.
Baade first referred to them as Hauptnovae: Osterbrock (2001), p. 32.
“forming one gigantic nucleus”: Landau (1932), p. 288.
would transform completely into naked spheres of neutrons: Baade and Zwicky (1934a), p. 263. It should be noted that astronomers later learned that there are essentially two types of supernovae: one, called Type II, involves a massive star’s core collapsing to either a neutron star or black hole; the other, Type I, is when a white dwarf steals gas from a companion. If enough matter is stolen, the dwarf star ignites in a runaway reaction that blows up the star.
only a handful of physicists . . . proceeded to investigate a neutron star’s possible structure: See Gamow (1937), Oppenheimer and Serber (1938), and Oppenheimer and Volkoff (1939).
“there is about as little hope of seeing such a faint object”: Wheeler (1964), p. 195.
“I like to say that I got my thesis with sledgehammering”: Bartusiak (1986), p. 42.
“there was a little bit of what I call ‘scruff’”: Kellermann and Sheets (1983), pp. 164–65.
“I was [then] two-and-a-half years through a three-year studentship”: Ibid., p. 168.
“lots of little green men on opposite sides of the universe”: Interview of Jocelyn Bell Burnell by David DeVorkin on May 21, 2000, Niels Bohr Library & Archives, American Institute of Physics, College Park, Maryland, www.aip.org/history-programs/niels-bohr-library/oral-histories/31792.
the news was finally released in February 1968: Hewish et al. (1968).
“One of [the photographers] even had me running down the bank”: Bell Burnell (1977), p. 688.
dubbed the novel objects pulsars: “Anthony Michaelis” (2008).
“likened to radio bursts from a solar flare”: Hewish et al. (1968), p. 712.
Thomas Gold developed the model that best explained a pulsar’s behavior: Gold (1968).
at least a few hundred million neutron stars now reside in the Milky Way: Camenzind (2007), p. 269.
Hewish had been skeptical about Bell’s “scruff”: Interview of Jocelyn Bell Burnell by David DeVorkin on May 21, 2000, Niels Bohr Library & Archives, American Institute of Physics, College Park, Maryland, www.aip.org/history-programs/niels-bohr-library/oral-histories/31792.
Nobel now stood for “No Bell”: Ibid.
“I believe it would demean Nobel Prizes”: Bell Burnell (1977), p. 688.
CHAPTER 8. YE OLD BLACK HOLE
Michell was a geologist, astronomer, mathematician, and theorist: Details of his life can be found in McCormmach (1968).
“the most inventive of the eighteenth-century natural philosophers”: Ibid., p. 127.
“father of modern seismology”: Hardin (1966), p. 30.
“short Man, of a black Complexion”: Ibid., p. 27.
“the odds against the contrary opinion”: Michell (1767), p. 249.
“arguably the most innovative and perceptive contribution”: Montgomery, Orchiston, and Whittingham (2009), p. 91.
he began monitoring and cataloging the stars positioned close together: Herschel (1782).
Michell decided to extend his ideas on double stars: Michell (1784).
Michell was devoted to the Society: Jungnickel and McCormmach (1999), p. 565, note 7.
some historians have speculated: Ibid., p. 564, and Montgomery, Orchiston, and Whittingham (2009), p. 91.
“diminution of the velocity”: Michell (1784), p. 35.
“all light . . . would be made to return”: Ibid., p. 42.
“A luminous star of the same density as the Earth”: Laplace (1809), p. 367.
he expunged his invisible-star speculation: Gillispie (1997), p. 175.
CHAPTER 9. AS THOUGH NO OTHER NAME EVER EXISTED
In June 1756, on the banks of the Hooghly river: Details of the Black Hole of Calcutta come from Cavendish (2006).
“Well, after I used that phrase four or five times”: Bartusiak (2000), p. 62.
their existence remained a well-kept secret: Interview with Joseph Taylor at Texas Symposium on Relativistic Astrophysics, December 2013.
Wheeler’s name is missing from the official conference proceedings: See Brancazio and Cameron (1969).
The term then made it into print: Wheeler (1968).
“Gravitational collapse would result”: Rosenfeld (1964), p. 11.
is sure he didn’t invent the term: Phone interview with Rosenfeld, 2012.
“space may be peppered with ‘black holes’”: Ewing (1964), p. 39.
originated the term quasar: Chiu (1964), p. 21.
“To the astonished audience, he jokingly added”: A letter dated May 25, 2009, describing Chiu’s knowledge on the origin of the term “black hole” was sent by Chiu to Physics Today. It was not published, but Chiu kindly provided a copy to me.
His sons told McHugh: An email from John Dicke to Loyala University physicist Martin McHugh, with the kind permission of both to use it.
“He simply started to use the name”: Thorne (1994), p. 256.
needed to be held at a distance within quotation marks: See Kafka (1969) and Sullivan (1968).
“He accused me of being naughty”: Wheeler and Ford (1998), p. 297.
“Thus black hole seems the ideal name”: Ibid.
“The advent of the term black hole”: Wheeler (1990), p. 3.
CHAPTER 10. LIKE THIS WORLD OF OURS
In 2017 an international team of astronomers thrillingly revealed: Gillon et al. (2017).
“infinite worlds both like and unlike”: Oates (1940), p. 5.
seemed logical that they’d ultimately construct: Dick (1998), p. 8.
“never be pe
rceived by us”: Herschel (1791), p. 74.
faster than any other star: Barnard (1916).
van de Kamp got worldwide attention: van de Kamp (1963).
failed to confirm the Barnard-star finding: Gatewood and Eichhorn (1973).
Bruce Campbell and Gordon Walker pioneered a way: Campbell and Walker (1979).
two momentous events: Aumann et al. (1984) and B. Smith and Terrile (1984).
“probably consists of ‘second generation’ planets”: Wolszczan and Frail (1992), p. 147.
That long-anticipated event: Mayor and Queloz (1995).
They first revealed their discovery: “51 Pegasi” (1995).
“spectacular detection”: Marcy and Butler (1996), p. L147.
Other discoveries followed swiftly: Ibid.
“reminiscent of solar system planets”: Butler and Marcy (1996), p. L153.
a trio of planets: Butler et al. (1999).
“We’ve gone from the early days”: Chu (2017).
“that stars are orbited by planets as a rule”: Cassan et al. (2012), p. 169.
CHAPTER 11. OUR SPIRALING HOME
one of the best baby pictures of the cosmos: Overbye (2013).
At first they tried just counting stars: Gingerich (1985), p. 59.
designated an “enemy alien”: Osterbrock (2001), p. 98.
Baade came to recognize that highly luminous blue and blue-white supergiant stars: Ibid., p. 102.