Famous Hydrogen Quotes

Parsons famously divided the social science world into a set of component "systems"—notably the social, the cultural, and the psychological—a division that by now seems as arbitrary as it was then influential, especially in its distinction between social structure and the cultural order. Even at the time, it struck some that the project was like analyzing water into its discernible ele­ments of hydrogen and oxygen in order to understand why it runs downhill.

Scientists expected that the Super, a fusion or "thermonuclear" weapon, would be an awesomely destructive horror that could unleash the equivalent of several million tons of TNT. This was hundreds of times more powerful than atomic bombs. A few well-placed hydrogen bombs could kill millions of people. Among the foes of development were famous scientists who had supported atomic development during World War II. One was Albert Einstein, who took to the radio to say that "general annilihation beckons.

In this chapter we will look at the entire edifice of QFT. We will see that it is based on three simple principles. We will also list some of its achievements, including some new insights and understandings not previously mentioned. THE FOUNDATION QFT is an axiomatic theory that rests on a few basic assumptions. Everything you have learned so far, from the force of gravity to the spectrum of hydrogen, follows almost inevitably from these three basic principles. (To my knowledge, Julian Schwinger is the only person who has presented QFT in this axiomatic way, at least in the amazing courses he taught at Harvard University in the 1950's.) 1. The field principle. The first pillar is the assumption that nature is made of fields. These fields are embedded in what physicists call flat or Euclidean three-dimensional space-the kind of space that you intuitively believe in. Each field consists of a set of physical properties at every point of space, with equations that describe how these particles or field intensities influence each other and change with time. In QFT there are no particles, no round balls, no sharp edges. You should remember, however, that the idea of fields that permeate space is not intuitive. It eluded Newton, who could not accept action-at-a-distance. It wasn't until 1845 that Faraday, inspired by patterns of iron filings, first conceived of fields. The use of colors is my attempt to make the field picture more palatable. 2. The quantum principle (discetization). The quantum principle is the second pillar, following from Planck's 1900 proposal that EM fields are made up of discrete pieces. In QFT, all physical properties are treated as having discrete values. Even field strengths, whose values are continues, are regarded as the limit of increasingly finer discrete values. The principle of discretization was discovered experimentally in 1922 by Otto Stern and Walther Gerlach. Their experiment (Fig. 7-1) showed that the angular momentum (or spin) of the electron in a given direction can have only two values: +1/2 or -1/2 (Fig. 7-1). The principle of discretization leads to another important difference between quantum and classical fields: the principle of superposition. Because the angular momentum along a certain axis can only have discrete values (Fig. 7-1), this means that atoms whose angular momentum has been determined along a different axis are in a superposition of states defined by the axis of the magnet. This same superposition principle applies to quantum fields: the field intensity at a point can be a superposition of values. And just as interaction of the atom with a magnet "selects" one of the values with corresponding probabilities, so "measurement" of field intensity at a point will select one of the possible values with corresponding probability (see "Field Collapse" in Chapter 8). It is discretization and superposition that lead to Hilbert space as the mathematical language of QFT. 3. The relativity principle. There is one more fundamental assumption-that the field equations must be the same for all uniformly-moving observers. This is known as the Principle of Relativity, famously enunciated by Einstein in 1905 (see Appendix A). Relativistic invariance is built into QFT as the third pillar. QFT is the only theory that combines the relativity and quantum principles.

The idea of an anthropic principle began with the remark that the laws of nature seem surprisingly well suited to the existence of life. A famous example is provided by the synthesis of the elements. According to modern ideas, this synthesis began when the universe was about three minutes old (before then it was too hot for protons and neutrons to stick together in atomic nuclei) and was later continued in stars. It had originally been though that the elements were formed by adding one nuclear particle at a time to atomic nuclei, starting with the simplest element, hydrogen, whose nucleus consists of just one particle (a proton). But, although there was no trouble in building up helium nuclei, which contain four nuclear particles (two protons and two neutrons), there is no stable nucleus with five nuclear particles and hence no way to take the next step. The solution found eventually by Edwin Salpeter in 1952 is that two helium nuclei can come together in stars to form the unstable nucleus of the isotope beryllium 8, which occasionally before it has a chance to fission into two helium nuclei absorbs yet another helium nucleus and forms a nucleus of carbon. However, as emphasized in 1954 by Fred Hoyke, in order for this process to account for the observed cosmic abundance of carbon, there must be a state of the carbon nucleus that has an energy that gives it an anomalously large probability of being formed in the collison of a helium nucleus and a nucleus of beryllium 8. (Precisely such a state was subsequently found by experimenters working with Hoyle.) Once carbon is formed in stars, there is no obstacle to building up all the heavier elements, including those like oxygen and nitrogen that are necessary for known forms of life. But in order for this to work, the energy of this state of the carbon nucleus must be very close to the energy of a nucleus of beryllium 8 plus the energy of a helium nucleus. If the energy of this state of the carbon nucleus were too large or too small, then little carbon or heavier elements would be formed in stars, and with only hydrogen and helium there would be no way that life could arise. The energies of nuclear states depend in a complicated way on all the constants of physics, such as the masses and electric charges of the different types of elementary particles. It seems at first sight remarkable that these constants should take just the values that are needed to make it possible for carbon to be formed in this way.

The fraction of the mass of two hydrogen atoms that is released as energy when they fuse to produce helium is 0.007 (0.7%). That is the source of the heat produced in the sun and in a hydrogen bomb. It is the amount of mass (m) that is converted to energy (E) in the famous Einstein formula E = mc2, and it is a direct measure of the strong nuclear force. If the strong force had a value of 0.006 or less, the universe would consist only of hydrogen—not very conducive to the complexities of life. If the value were greater than 0.008, all the hydrogen would have been fused shortly after the big bang, and there could be no stars, no solar heat—again, no life. As Stephen Hawking and Leonard Mlodinow put it in their book The Grand Design, “Our universe and its laws appear to have a design that both is tailor-made to support us and, if we are to exist, leaves little room for alteration.

The fraction of the mass of two hydrogen atoms that is released as energy when they fuse to produce helium is 0.007 (0.7%). That is the source of the heat produced in the sun and in a hydrogen bomb. It is the amount of mass (m) that is converted to energy (E) in the famous Einstein formula E = mc2, and it is a direct measure of the strong nuclear force. If the strong force had a value of 0.006 or less, the universe would consist only of hydrogen—not very conducive to the complexities of life. If the value were greater than 0.008, all the hydrogen would have been fused shortly after the big bang, and there could be no stars, no solar heat—again, no life. As Stephen Hawking and Leonard Mlodinow put it in their book The Grand Design, “Our universe and its laws appear to have a design that both is tailor-made to support us and, if we are to exist, leaves little room for alteration.

The fraction of the mass of two hydrogen atoms that is released as energy when they fuse to produce helium is 0.007 (0.7%). That is the source of the heat produced in the sun and in a hydrogen bomb. It is the amount of mass (m) that is converted to energy (E) in the famous Einstein formula E = mc2, and it is a direct measure of the strong nuclear force. If the strong force had a value of 0.006 or less, the universe would consist only of hydrogen—not very conducive to the complexities of life. If the value were greater than 0.008, all the hydrogen would have been fused shortly after the big bang, and there could be no stars, no solar heat—again, no life. As Stephen Hawking and Leonard Mlodinow put it in their book The Grand Design, “Our universe and its laws appear to have a design that both is tailor-made to support us and, if we are to exist, leaves little room for alteration.

Early on, advocates of big bang cosmology realized that the universe is evolutionary. In the words of one famous cosmologist, George Gamov, “We conclude that the relative abundances of atomic species represent the most ancient archaeological document pertaining to the history of the universe.” In other words, the periodic table is evidence of the evolution of matter, and atoms can testify to the history of the cosmos. But early versions of big bang cosmology held that all the elements of the universe were fused in one fell swoop. As Gamov puts it, “These abundances …” meaning the ratio of the elements (heaps of hydrogen, hardly any gold—that kind of thing), “… must have been established during the earliest stages of expansion, when the temperature of the primordial matter was still sufficiently high to permit nuclear transformations to run through the entire range of chemical elements.” It was a neat idea, but very wrong. Only hydrogen, helium, and a dash of lithium could have formed in the big bang. All of the elements heavier than lithium were made much later, by being fused in evolving and exploding stars. How do we know this? Because at the same time some scholars were working on the big bang theory, others were trying to ditch the big bang altogether. Its association with thermonuclear devices made it seem hasty, and its implied mysterious origins tainted it with creationism. And so, a rival camp of cosmologists developed an alternate theory: the Steady State. The Steady State held that the universe had always existed. And always will. Matter is created out of the vacuum of space itself. Steady State theorists, working against the big bang and its flaws, were obliged to wonder where in the cosmos the chemical elements might have been cooked up, if not in the first few minutes of the universe. Their answer: in the furnaces of the very stars themselves. They found a series of nuclear chain reactions at work in the stars. First, they discovered how fusion had made elements heavier than carbon. Then, they detailed eight fusion reactions through which stars convert light elements into heavy ones, to be recycled into space through stellar winds and supernovae. And so, it’s the inside of stars where the alchemist’s dream comes true. Every gram of gold began billions of years ago, forged out of the inside of an exploding star in a supernova. The gold particles lost into space from the explosion mixed with rocks and dust to form part of the early Earth. They’ve been lying in wait ever since.

One way that scientists have tried to figure out how sustainable cells came to be is by attempting to simulate the early chemistry of a primordial pond or ocean. The most famous example is an experiment performed by Stanley Miller, working in the Harold Urey laboratory in the 1950s. Miller put chemicals that he thought might have been present in the primordial atmosphere (hydrogen, ammonia, and methane gases) in water and passed electricity (simulating lightning) through the mixture, hoping to trigger the conversion of prebiotic carbon-based compounds into biological compounds (figure 12.1). Several days later Miller found that amino acids, which are the building blocks of proteins, a key ingredient of life, had formed, demonstrating that inorganic elements, in the presence of heat, can form biological compounds.