The Lightness of Being Quotes

“The legendary Danish physicist Niels Bohr distinguished two kinds of truths. An ordinary truth is a statement whose opposite is a falsehood. A profound truth is a statement whose opposite is also a profound truth.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“We know even less about dark energy. It seems to spread out perfectly evenly, with the same density everywhere and everywhen, as if it were an intrinsic property of space-time. Unlike any conventional kind of matter (even supersymmetric particles or axions), the dark energy exerts negative pressure. It tries to pull you apart! Fortunately, although dark energy supplies about 70% of the mass of the universe as a whole, its density is only about 7 X 10 ^-30 times the density of water, and its negative pressure cancels only about 7 X 10 ^-14 of normal atmospheric pressure-less than a part in a trillion. I don't know when we'll have clearer ideas about what the dark energy is. I'd guess not very soon. I hope I'm wrong.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Planck noted that although the Andromedans wouldn't have access to our rulers, scales, or clocks, they would have access to our physical laws, which are the same as theirs. They could measure, in particular, three universal constants:

c: The speed of light.

G: Newton's gravitational constant. In Newton's theory, this is a measure of the strength of gravity. To be precise, in Newton's law of gravity, the gravitational force between the bodies of masses m1, m2 separated by distance r is Gm1m2/r^2.

h: Planck's constant.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“The entity we perceive as empty space is a multilayered, multicolored superconductor. What an amazing, astonishing, beautiful, breathtaking concept. Extraordinary, too.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Gravity is the dominant force in astronomy, but only by default. Other interactions are far stronger, but they feature both attractions and repulsions. Normally matter reaches an accurate equilibrium, with the forces cancelled. Temporary imbalances (small ones) among electric forces lead to lightning storms; small temporary imbalances among strong forces induce nuclear explosions. Gross breakdowns of equilibrium cannot stand. Gravity, however, is always attractive. Though feeble at the level of individual basic particles, gravitational forces inexorably add up. The meek inherit the cosmos.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Music of the Grid:

A Poem in Two Equations
_________________________

The masses of particles sound the frequencies with which space vibrates, when played. This Music of the Grid betters the old mystic mainstay, "Music of the Spheres," both in fantasy and in realism.

LET US COMBINE Einstein's second law

m=E/C^2 (1)

with another fundamental equation, the Planck-Einstein-Schrodinger formula

E = hv

The Planck-Einstein-Schrodinger formula relates the energy E of a quantum-mechanical state to the frequency v at which its wave function vibrates. Here h is Planck's constant. Planck introduced it in his revolutionary hypothesis (1899) that launched quantum theory: that atoms emit or absorb light of frequency v only in packets of energy E = hv. Einstein went a big step further with his photon hypothesis (1905): that light of frequency v is always organized into packets with energy E = hv. Finally Schrodinger made it the basis of his basic equation for wave functions-the Schrodinger equation (1926). This gave birth to the modern, universal interpretation: the wave function of any state with energy E vibrates at a frequency v given by v = E/h.

By combining Einstein with Schrodinger we arrive at a marvelous bit of poetry:

(*) v = mc^2/h (*)

The ancients had a concept called "Music of the Spheres" that inspired many scientists (notably Johannes Kepler) and even more mystics. Because periodic motion (vibration) of musical instruments causes their sustained tones, the idea goes, the periodic motions of the planets, as they fulfill their orbits, must be accompanied by a sort of music. Though picturesque and soundscape-esque, this inspiring anticipation of multimedia never became a very precise or fruitful scientific idea. It was never more than a vague metaphor, so it remains shrouded in equation marks: "Music of the Spheres."

Our equation (*) is a more fantastic yet more realistic embodiment of the same inspiration. Rather than plucking a string, blowing through a reed, banging on a drumhead, or clanging a gong, we play the instrument that is empty space by plunking down different combinations of quarks, gluons, electrons, photons,... (that is, the Bits that represent these Its) and let them settle until they reach equilibrium with the spontaneous activity of Grid. Neither planets nor any material constructions compromise the pure ideality of our instrument. It settles into one of its possible vibratory motions, with different frequencies v, depending on how we do the plunking, and with what. These vibrations represent particles of different mass m, according to (*). The masses of particles sound the Music of the Grid.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“So: What is the world made of? Subject, as ever, to addition and correction, here is the multifaceted answer that modern physics provides:

1) The primary ingredient of physical reality, from which all else is formed, fills space and time.

2) Every fragment, each space-time element, has the same basic properties as every other fragment.

3) The primary ingredient of reality is alive with quantum activity. Quantum activity has special characteristics. It is spontaneous and unpredictable. And to observe quantum activity, you must disturb it.

4) The primary ingredient of reality also contains enduring material components. These make the cosmos a multilayered, multicolored superconductor.

5) The primary ingredient of reality contains a metric field that gives space-time rigidity and causes gravity.

6) The primary ingredient of reality weighs, with a universal density.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“In the same movie, Emperor Joseph II offers Mozart some musical advice: "Your work is ingenious. It's quality work. And there are simply too many notes, that's all. Just cut a few and it will be perfect." The emperor was put off by the surface complexity of Mozart's music. He didn't see that each note served a purpose-to make a promise or fulfill one, to complete a pattern or vary one.

Similarly, at first encounter people are sometimes put off by the superficial complexity of fundamental physics. Too many gluons!

But each of the eight color gluons is there for a purpose. Together, they fulfill complete symmetry among the color charges. Take one gluon away, or change its properties, and the structure would fall. Specifically, if you make such a change, then the theory formerly known as QCD begins to predict gibberish; some particles are produced with negative probabilities, and others with probability greater than 1. Such a perfectly rigid theory, one that doesn't allow consistent modification, is extremely vulnerable. If any of its predictions are wrong, there's nowhere to hide. No fudge factors or tweaks are available. On the other hand, a perfectly rigid theory, once it shows significant success, becomes very powerful indeed. Because if it's approximately right and can't be changed, then it must be exactly right!

Salieri's criteria explain why symmetry is such an appealing principle for theory building. Systems with symmetry are well on the path to Salieri's perfection. The equations governing different objects and different situations must be strictly related, or the symmetry is diminished. With enough violations all pattern is lost, and the symmetry falls. Symmetry helps us make perfect theories.

So the crux of the matter is not the number of notes or the number of particles or equations. It is the perfection of the designs they embody. If removing any one would spoil the design, then the number is exactly what it should be. Mozart's answer to the emperor was superb: "Which few did you have in mind, Majesty?”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Supersymmetry was (and is) a beautiful mathematical idea. The problem with applying supersymmetry is that it is too good for this world. We simply do not find particles of the sort it predicts. We do not, for example, see particles with the same charge and mass as electrons, but a different amount of spin.

However, symmetry principles that might help to unify fundamental physics are hard to come by, so theoretical physicists do not give up on them easily. Based on previous experience with other forms of symmetry, we have developed a fallback strategy, called spontaneous symmetry breaking. In this approach, we postulate that the fundamental equations of physics have the symmetry, but the stable solutions of these equations do not. The classic example of this phenomenon occurs in an ordinary magnet. In the basic equations that describe the physics of a lump of iron, any direction is equivalent to any other, but the lump becomes a magnet with some definite north-seeking pole.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“In one of my favorite scenes from one of my favorite movies, Amadeus, Salieri looks with wide-eyed astonishment at a manuscript of Mozart's and says, "Displace one note and there would be diminishment. Displace one phrase and the structure would fall."

In this, Salieri captured the essence of perfection. His two sentences define precisely what we mean by perfection in many contexts, including theoretical physics. You might say it's a perfect definition.

A theory begins to be perfect if any change makes it worse. That's Salieri's first sentence, translated from music to physics. And it's right on point. But the real genius comes with Salieri's second sentence. A theory becomes perfectly perfect if it's impossible to change it significantly without ruining it entirely-that is, if changing the theory significantly reduces it to nonsense.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“The world is no longer founded on atoms in the void, so the state of the world no longer consists of the positions and velocities of a lot of atoms. Instead, the world is the tremendous mutliple infinity of qubits just described. And to describe its state we must assign a number-a probability amplitude-to every possible configuration of the qubits. In our five-qubit toy model we found that the possible states filled out a space of thirty-two dimensions. The space we must use to describe the state of the Grid, which is our world, brings in infinities of infinities.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Recapitulation

At the beginning of this chapter, I advertised key properties of the Grid, that ur-stuff that underlies physical reality:

The grid fills space and time.

Every fragment of Grid-each space-time element-has the same basic properties as every other fragment.

The Grid is alive with quantum activity. Quantum activity has special characteristics. It is spontaneous and unpredictable. And to observe quantum activity, you must disturb it.

The Grid also contains enduring , material components. The cosmos is a multilayered, multicolored superconductor.

The Grid contains a metric field that gives space-time rigidity and causes gravity.

The Grid weighs, with a universal density.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“A modern, secular version of Augustine's question is "What happened before the big bang?" And a version of his second answer based on physics might apply. Not that minds are necessary for time-I don't think many physicists would accept that (and the equations of physics certainly don't). But if the metric field vaporizes, with it goes the standard of time. Once no clocks exist (and this means an end not just to elaborate time-keeping devices, but to every physical process that could serve to mark time), time itself, along with the whole notion of "before," loses any meaning. The flow of time commences with the condensation of the metric field.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Quantum fields fill all all space, and the quantum electric and magnetic fields obey Maxwell's equations. Nevertheless, when you observe the quantum fields, you find their energy packaged in discrete units: photons.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“(The cosmological constant is, essentially, the density of empty space. Anticipating a little, let me just mention that a big puzzle in modern physics is why empty space weighs so little even though there's so much to it.)”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Ordinary matter is a secondary manifestation of the Grid, tracing its level of excitation.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Our clever friend Feynman demonstrated how to write down the Equation of the Universe in a single line. Here it is:

U = 0

U is a definite mathematical function, the total unworldliness. It's the sum of contributions from all the piddling partial laws of physics. To be precise, U = Unewton + Ueinstein +.... Here, for instance, the Newtonian mechanical unworldiness Unewton is defined by Unewton = (F - ma)^2; the Einstein mass-energy Unworldliness is definedby Ueinstein = (E - mc^2) ^2; and so forth. Because every contribution is positive or zero, the only way that the total U can vanish is for every contribution to vanish, so U = 0 implies F=ma, E=mc^2, and any other past or future law you care to include!

Thus we can capture all the laws of physics we know, and accommodate all the laws yet to be discovered, in one unified equation. The Theory of Everything!!! But it's a complete cheat, of course, because there is no way to use (or even define) U, other than to deconstruct it into its separate pieces and then use those.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“If we know an object has symmetry, we can deduce some of its properties. If we know a set of objects has symmetry, we can infer from our knowledge of one object the existence and properties of others. And if we know that the laws of the world have symmetry, we can infer from one object the existence, properties, and behavior of new objects.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Let's imagine we're virtual particles. We pop into existence and have to decide what to do in our all-too-brief lifetime. (That's not so hard to imagine.) We sniff around. Suppose there's a positively charged particle in the region. If we're negatively charged, we find that particle attractive and try to snuggle up to it. If we're positively charged, we find that other particle repulsive, or at least competitive and possibly intimidating, and we move away. (Neither is that.)”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“The relevant facts can be summarized in a few sentences. (I won't try to do it in one.) All things are made from atoms and photons. Atoms in turn are made from electrons and atomic nuclei. The nuclei are very much smaller than the atoms as a whole (they have roughly one-hundred-thousandth, or 10^-5, the radius), but they contain all the positive electric charge and nearly all the mass of the atom-more than 99.9%. Atoms are held together by electrical attraction between the electrons and the nuclei. Finally, nuclei in turn are made from protons and neutrons. The nuclei are held together by another force, a force that is much more powerful than the electric force but acts only over short distances.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“The best way to address the big ultimate questions is likely to be through dialogue with Nature. We must pose pointed sub-questions that give Nature a chance to respond with meaningful answers, in particular with answers that might surprise us.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Matter is not what it appears to be. Its most obvious property-variously called resistance to motion, inertia, or mass- can be understood more deeply in completely different terms. The mass of ordinary matter is the embodied energy of more basic building blocks, themselves lacking mass. Nor is space what it appears to be. What appears to our eyes as empty space is revealed to our minds as a complex medium full of spontaneous activity.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“It is more blessed to ask forgiveness than permission.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“chromodynamics”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“We can describe general relativity using either of two mathematically equivalent ideas: curved space-time or metric field. Mathematicians, mystics, and specialists in general relativity tend to like the geometric view because of its elegance. Physicists trained in the more empirical tradition of high-energy physics and quantum field theory tend to prefer the field view...More important, as we'll see in a moment, the field view makes Einstein's theory of gravity look more like the other successful theories of fundamental physics, and so makes it easier to work toward a fully integrated, unified description of all the laws. As you can probably tell, I'm a field man.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“For the first step, we need much more efficient Grid supercurrents. They must mightily suppress the unwanted strong<>weak color charge transformations. Of course, this means that the supercurrents themselves would be flows involving both strong and weak color charges.

No known form of matter can supply such supercurrents. On the other hand, it's easy to invent new Higgs-like fields that do the job. People have played with other ideas, too. Maybe these currents arise from particles racing around in additional, tiny cureled-up spatial dimensions. Maybe they're vibrations of strings that wrap around additional tiny curled-up spatial dimensions. Because the concentrated energies required to probe distances this small lie far, far beyond what we can achieve in practice, these speculations are not easy to check.

Fortunately, just as in the Core electroweak theory, we can make good progress by taking the supercurrents as given, without fingo-ing hypotheses about what they're made of. That's the philosophy I adopted in Part III of this book. It led us to some encouraging successes, and to some specific predictions. If it survives further scrutiny, we'll be able to assert with confidence that we live within a multilayered, multicolored cosmic superconductor.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“Unification of our theories of the Core interactions-strong, weak, and electromagnetic-into a single unified theory involves some guesswork, but the principles are clear. Quantum mechanics, special relativity, and (local) symmetry fit together smoothly. Using them, we can make definite suggestions for experimental exploration, including quantitative estimates of what to expect.

Unification with gravity also looks good, at the level of comparing the fundamental strength of all the interactions, as we've seen. But with gravity our ideas about what the unified theory is are nowhere near as concrete. The ferment of ideas around super-string theory seems promising, but no one's been able to pull these ideas together enough to suggest specifically what new effects to expect.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“There's another promising idea about what the dark matter is, which emerges from a different proposal for improving the equations of physics. As we've discussed, QCD is in a profound and literal sense constructed as the embodiment of symmetry. There is an almost perfect match between the observed properties of quarks and gluons and the most general properties allowed by local color symmetry, in the framework of special relativity and quantum mechanics. The only exception is that the established symmetries of QCD fail to forbid one sort of behavior that is not observed to occur. The established symmetries permit a sort of interaction among gluons that would spoil the symmetry of the equations of QCD under a change in the direction of time. Experiments provide severe limits on the possible strength of that interaction. The limits are much more severe than might be expected to arise accidentally.

The Core theory does not explain this "coincidence." Roberto Peccei and Helen Quinn found a way to expand the equations that would explain it. Steven Weinberg and I, independently, showed that the expanded equations predict the existence of new, very light, very weakly interacting particles called axions. Axions are also serious candidates to provide the cosmological dark matter. In principle they might be observed in a variety of ways. Though none is easy, the hunt is on.

It's also possible that both ideas are right, and both kinds of particles contribute to the total amount of dark matter. Wouldn't that be pretty?”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“We've seen that the theories of the Core forces, each deeply based on symmetry, can be combined. The three separate Core symmetries can be realized as parts of a single, all-encompassing symmetry. Moreover, that encompassing symmetry brings unity and coherence to the clusters of the Core. From a motley six, we assemble the faultless Charge Account. We also discover that once we correct for the distorting effect of Grid fluctuations-and after upping the ante to include SUSY-the different powers of the Core forces derive from a common value at short distances. Even gravity, that hopelessly feeble misfit, comes into the field.

To reach this clear and lofty perspective, we made some hopeful leaps of imagination. We assumed that the Grid-the entity that in everyday life we consider empty space-is a multilayered, multicolored superconductor. We assumed that the world contains the extra quantum dimensions required to support super-symmetry. And we boldly took the laws of physics, supplemented with these two "super" assumptions, up to energies and down to distances far beyond where we've tested them directly.

From the intellectual success so far achieved-from the clarity and coherence of this vision of unification-we are tempted to believe that our assumptions correspond to reality. But in science, Mother Nature is the ultimate judge.

After the solar expedition of 1919 confirmed his prediction for the bending of light by the Sun, a reporter asked Albert Einstein what it would have meant if the result had been otherwise. He replied, "Then God would have missed a great opportunity." Nature doesn't miss such opportunities. I anticipated that Nature's verdicts in favor of our "super" ideas will inaugurate a new golden age in fundamental physics.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces

“As we discussed way back in Chapter 3, gravity responds directly to energy. Its power, as defined here, is proportional to energy squared. Allowing for that effect, we can calculate the power of gravity at short distances and compare it with the other interactions. Figure 20.2 displays the result. From well outside the known universe, the inverse power of gravity descends to join the other interactions, pretty nearly.”
― Frank Wilczek, The Lightness of Being: Mass, Ether, and the Unification of Forces