The Expanding Universe
In 1929 Hubble published evidence that the universe is expanding, refuting the idea that the universe is static. This discovery irritated Einstein. It tore down the conceptual wall Einstein had built to keep God out. A year or so later, Lemaître showed that the general relativity equations had a solution for an expanding universe and thereby gained a hearing with Einstein. Over a period of several days in private meetings Lemaître persuaded Einstein to change his mind and let his equations speak for themselves. Eventually Einstein visited Mount Wilson in California and looked through the 100-inch Hooker telescope that Hubble had used to gather his data. Einstein then and there repudiated the special value of the cosmological constant. Later, in private communications with his friend Gamow, Einstein admitted that his choice for the value of the cosmological constant was “the biggest blunder” of his scientific career.
Einstein looks through the large telescope of the Mount Wilson Observatory in California as Hubble seems to worry.
The Giant Atom That Exploded
Lemaître and Gamow thought that, in the beginning, a nuclear explosion produced the universe. Lemaître was right insofar as he persuaded Einstein to accept the evidence that the universe had a beginning. He was also right in thinking that the initial energy must have been highly organized. However, the model Lemaître depicted at the time is not correct.
Lemaître wrote in 1931, when atomic theory was still in its early stages of development.[i] He proposed that the universe was once highly organized as a gigantic atom.[ii] Physicists already knew that the heaviest natural elements are unstable and may break up spontaneously into smaller atoms. Lemaître thought in 1931 that science would eventually discover atoms with millions or billions or trillions of particles. He said that perhaps all the particles in the universe were part of one huge atom originally. Quantum mechanics had already established that the energy of atomic orbitals is proportional to the square of the atomic number. Lemaître reasoned that the energy of the primordial atom would involve very large quantum numbers. The energy would be well organized like money paid in bills worth $10 000 each. Such a huge atom would surely be unstable and at an unpredictable time it would explode like a huge atomic bomb.
[i] Lemaître, Georges, “The beginning of the world from the point of view of quantum theory,” Nature, 127 (Number 3210, 9 May 1931), p. 706.
[ii] Lemaître, Georges, “I propose to give some answer to the two questions raised by Sir James Jeans,” Supplement to Nature, 127 (Number 3210, 24 October 1931), pp. 704–706.
Scientists can now make atoms with more than a hundred protons, but the bigger the atoms are, the faster they break up spontaneously into smaller, stable atoms. Nobody is now asking who put the primordial atom together, because we now know that such huge atoms do not exist. Lemaître was wrong about huge atoms, but he was right in thinking that the universe must have begun in a highly organized state.
The present idea is that the initial energy of the universe was organized in cosmic rays of very high vibration frequency. The energy of a photon is directly proportional to the vibration rate. Therefore, in the beginning the highly organized energy was the electromagnetic energy of cosmic rays, not the energy of material particles in an atom. Later part of the energy materialized as subatomic particles, and the rest of the energy broke up into many rays of lower energies, including rays of light and heat.
Expansion, Not a “Big Bang” Explosion
Lemaître started the idea that the universe began with an explosion. He was also wrong about that. The universe did not explode. It expanded. Explosions disrupt existing order, but the expansion of the universe was orderly. Astronomers have photographed the universe as it was after a great deal of expansion. Considerable order is still clearly visible, particularly the order of uniformity or homogeneity. The first light has the same temperature everywhere to within a few tens of microkelvins.
Random action makes some parameters regular through the statistical “law of large numbers.” This means that random processes produce very regular averages when there are many particles involved.
Random collisions of air molecules keep the air pressure nearly constant in our bedrooms. Who could sleep fearing that the air might suddenly collapse into a thin layer on the floor and stay there for 10 minutes? Happily the probability of that happening is so small we may as well just say it is impossible.
Random action produces the characteristics of thermal light, light from incandescent sources. The first light is the most perfectly thermal light we have ever detected.
For these reasons it is not correct to say that the universe began with a “big bang.” P. J. E. Peebles explains what is wrong with this idea.
The familiar name for this picture, the “big bang” cosmological model, is unfortunate because it suggests we are identifying an event that triggered the expansion of the universe, and it may also suggest the event was an explosion localized in space. Both are wrong. The universe we observe is inferred to be close to homogeneous, with no evidence for a preferred center that might have been the site of an explosion. The standard cosmological picture deals with the universe as it is now and as we can trace its evolution back in time through an interlocking network of observation and theory. We have evidence from the theory of the origin of the light elements that the standard model successfully describes the evolution back to a time when the mean distance between conserved particles was some ten orders of magnitude smaller than it is now. If it is found that still earlier epochs left evidence that can be analyzed and used to test our ideas, then that may be incorporated in the standard model or some extension of it. If there were an instant, at a “big bang,” when our universe started expanding, it is not in the cosmology as now accepted, because no one has thought of a way to adduce objective physical evidence that such an event really happened.[i]
[i] Peebles, P. J. E., Principles of Physical Cosmology (Princeton, New Jersey: Princeton University Press, 1993), p. 6.
Later Peebles suggests that instead of saying “the Big Bang” we should substitute the name “the standard expanding world picture.” The Bible puts the idea more simply, stating that God put expansion in the heavens.
Lemaître and Gamow thought that, in the beginning, a nuclear explosion produced the universe. Lemaître was right insofar as he persuaded Einstein to accept the evidence that the universe had a beginning. He was also right in thinking that the initial energy must have been highly organized. However, the model Lemaître depicted at the time is not correct.
Lemaître wrote in 1931, when atomic theory was still in its early stages of development.[i] He proposed that the universe was once highly organized as a gigantic atom.[ii] Physicists already knew that the heaviest natural elements are unstable and may break up spontaneously into smaller atoms. Lemaître thought in 1931 that science would eventually discover atoms with millions or billions or trillions of particles. He said that perhaps all the particles in the universe were part of one huge atom originally. Quantum mechanics had already established that the energy of atomic orbitals is proportional to the square of the atomic number. Lemaître reasoned that the energy of the primordial atom would involve very large quantum numbers. The energy would be well organized like money paid in bills worth $10 000 each. Such a huge atom would surely be unstable and at an unpredictable time it would explode like a huge atomic bomb.
[i] Lemaître, Georges, “The beginning of the world from the point of view of quantum theory,” Nature, 127 (Number 3210, 9 May 1931), p. 706.
[ii] Lemaître, Georges, “I propose to give some answer to the two questions raised by Sir James Jeans,” Supplement to Nature, 127 (Number 3210, 24 October 1931), pp. 704–706.
Scientists can now make atoms with more than a hundred protons, but the bigger the atoms are, the faster they break up spontaneously into smaller, stable atoms. Nobody is now asking who put the primordial atom together, because we now know that such huge atoms do not exist. Lemaître was wrong about huge atoms, but he was right in thinking that the universe must have begun in a highly organized state.
The present idea is that the initial energy of the universe was organized in cosmic rays of very high vibration frequency. The energy of a photon is directly proportional to the vibration rate. Therefore, in the beginning the highly organized energy was the electromagnetic energy of cosmic rays, not the energy of material particles in an atom. Later part of the energy materialized as subatomic particles, and the rest of the energy broke up into many rays of lower energies, including rays of light and heat.
Expansion, Not a “Big Bang” Explosion
Lemaître started the idea that the universe began with an explosion. He was also wrong about that. The universe did not explode. It expanded. Explosions disrupt existing order, but the expansion of the universe was orderly. Astronomers have photographed the universe as it was after a great deal of expansion. Considerable order is still clearly visible, particularly the order of uniformity or homogeneity. The first light has the same temperature everywhere to within a few tens of microkelvins.
Random action makes some parameters regular through the statistical “law of large numbers.” This means that random processes produce very regular averages when there are many particles involved.
Random collisions of air molecules keep the air pressure nearly constant in our bedrooms. Who could sleep fearing that the air might suddenly collapse into a thin layer on the floor and stay there for 10 minutes? Happily the probability of that happening is so small we may as well just say it is impossible.
Random action produces the characteristics of thermal light, light from incandescent sources. The first light is the most perfectly thermal light we have ever detected.
For these reasons it is not correct to say that the universe began with a “big bang.” P. J. E. Peebles explains what is wrong with this idea.
The familiar name for this picture, the “big bang” cosmological model, is unfortunate because it suggests we are identifying an event that triggered the expansion of the universe, and it may also suggest the event was an explosion localized in space. Both are wrong. The universe we observe is inferred to be close to homogeneous, with no evidence for a preferred center that might have been the site of an explosion. The standard cosmological picture deals with the universe as it is now and as we can trace its evolution back in time through an interlocking network of observation and theory. We have evidence from the theory of the origin of the light elements that the standard model successfully describes the evolution back to a time when the mean distance between conserved particles was some ten orders of magnitude smaller than it is now. If it is found that still earlier epochs left evidence that can be analyzed and used to test our ideas, then that may be incorporated in the standard model or some extension of it. If there were an instant, at a “big bang,” when our universe started expanding, it is not in the cosmology as now accepted, because no one has thought of a way to adduce objective physical evidence that such an event really happened.[i]
[i] Peebles, P. J. E., Principles of Physical Cosmology (Princeton, New Jersey: Princeton University Press, 1993), p. 6.
Later Peebles suggests that instead of saying “the Big Bang” we should substitute the name “the standard expanding world picture.” The Bible puts the idea more simply, stating that God put expansion in the heavens.