Physicists From The United States

"With respect to science, the assumption behind consensus is that science is a source of authority and that authority increases with the number of scientists. Of course, science is not primarily a source of authority. Rather, it is a particularly effective approach to inquiry and analysis. Skepticism is essential to science; consensus is foreign."

"The notion that global warming is a fact and will be catastrophic is drilled into people to the point where it seems surprising that anyone would question it, and yet, underlying it is very little evidence at all. Nonetheless, there are statements made of such overt unrealism that I feel embarrassed. I feel it discredits science. I think problems will arise when one will need to depend on scientific judgment, and by ruining our credibility now you leave society with a resource of some importance diminished."

"# The trait that to me seems the most socially important about science, however, is that it is a major source of man's discontent with the status quo..."

"# Moreover, the pace of technological advance gravely threatens the bountiful and restorative power of nature to resist modification..."

"# Another trait of science that leads to much hostility or misunderstanding by the non-scientist is the fact that science is practiced by a small elite... (which) has cultural patterns discernibly different from those of the rest of society..."

"is about the gravity of empty space, the gravity of the vacuum. And the vacuum is a concept that we address in and quantum mechanics. Quantum mechanics is physics on microscopic scales, while Einstein's theory of general relativity ... is physics on macroscopic scales. These two theories are both great, but they don't work together. We don't have what's called a quantum theory of gravity, the way the two are united. However, dark energy actually requires you to use both of these branches of physics. So our hope is that by observing how the universe actually does physics at that interface, we will learn how to unify those."

"Less than a century ago we had no idea that there was more to the universe than our own Milky Way. the immense size of the universe, the fact that it is expanding, the fact that it is populated with such things as – all this and more had to be discovered before we could do the work that led us to contemplate an ."

"I think . I never would have guessed it. Even as an undergraduate, once I’d learned a little physics, I would have thought that the universe was eternal, static, and always in equilibrium. So in graduate school when I found out that the universe was expanding, I was awestruck. Then I learned if we could measure the expanding universe, the way we record the growth of a child with marks on a doorframe ... , we could determine the age of the universe and predict its ultimate fate. This was staggering! I knew this is what I wanted to do. Since that time, charting the expanding universe to determine its nature has been my passion. Though I have to add: knowing what I know now, that the , I feel like King Alfonso X of Castile who saw Ptolemy’s and reportedly said “If the Lord Almighty had consulted me before embarking on creation thus, I should have recommended something simpler.”"

"Having that bit of diabolical contrariness is a weird pleasure of being a scientist. You’re always trying to figure out, “OK, how could I be fooling myself into a wrong conclusion?” Because the more you get those things right, the more chances you have of catching the universe doing something that our brains never would’ve imagined. Scientists build out of what seems like a stance of weakness. So, one might think it’s terrible that scientists are always discovering new ways that they’re wrong, or it’s terrible that they’re only probabilistically sure of facts. But that’s really where scientists’ superpower has come from. We have been able to figure out amazing solutions to problems or surprises about the world. Much of that can be traced back to being willing to be wrong and being comfortable with finding the ways you’re wrong. And for this purpose, you want to build strong relationships with people who are going to tell you when you’re wrong, who will disagree with you, or who compete with you. They’re your best bet at figuring out where you’re making a mistake."

"# Science is constantly, systematically and inexorably revisionary. It is a self-correcting process and one that is self-destroying of its own errors..."

"Not only does it swallow anything that comes too near it but no one lives to tell the tale ... there are footprints leading in, and no footprints leading out ... If black holes weren’t real, I think the science-fiction writers would have wanted to invent them."

"Today we are able to make very precise measurements of the by measuring the distances and s of . The shift in a supernova’s due to the expansion of space gives its redshift (z) and the relation between redshift and distance is used to determine the expansion rate of the universe. Supernovae with greater redshifts, lying at greater distances, reveal the past expansion rate as their light was emitted at an epoch when the universe was younger. Supernovae Type Ia were the suitable candidate for these measurements as you need objects that are very luminous (thus can be observed even when they are very far) and highly uniform (so that intrinsic scatter doesn't blur the signal). Supernovae Type Ia are the most luminous of the common supernova types, peaking at 4 billion , and thus allowing us to look at extreme large distances."

"# A related trait of science is its destruction of idols, destruction of the gods men live by... Science has no absolute right or absolute justice... To live comfortably with science it is necessary to live with a dynamically changing system of concepts... it has a way of weakening old and respected bonds..."

"# Not only are the tenets of science constantly subject to challenge and revision, but its prophets are under challenge too..."

"# Certainly we have seen spectacular changes in the concept of private property and of national borders as we have moved into the space age..."

"# Further, the findings of science have an embarrassing way of turning out to be relevant to the customs and to the civil laws of men—requiring these customs and laws also to be revised..."

"For a million years, our species was confronted with a world we could not hope to understand. Now, within a span of a single human lifetime, the book of nature has been opened wide. On its pages we are finding, if not a simple world, at least an orderly world in which everything from the birth of stars to falling in love is governed by the same natural laws."

"Those [natural] laws cannot be circumvented by any amount of piety or cleverness, but they can be understood. Uncovering them should be the highest goal of a civilized society. Not...because scientists have any claim to greater intellect or virtue, but because the scientific method transcends the flaws of individual scientists. Science is the only way we have of separating the truth from ideology, or fraud, or mere foolishness."

"They are betting against the laws of thermodynamics. No one has ever won that wager."

"[T]he uniquely American myth of the self-educated genius fighting against a pompous, close-minded establishment."

"The integrity of science is anchored in the willingness of scientists to test their ideas and results in direct confrontation with their scientific peers."

"A scientist looks for a description of the universe in terms of a model that allows him to understand how things work, allows him to predict how things are going to work, and allows him to put together devices that work according to his predictions."

"What may begin as an honest error...has a way of evolving through almost imperceptible steps from self-delusion to fraud. The line between foolishness and fraud is thin. Because it is not always easy to tell when that line is crossed, I use the term voodoo science to cover them all: pathological science, junk science, pseudoscience and fraudulent science."

"Every step taken by science claims territory once occupied by the supernatural."

"Two hundred years ago, educated people imaged that the greatest contribution of science would be to free the world of superstition and humbug. It has not happened. Ancient beliefs in demons and magic still sweep across the modern landscape, but they are now dressed in the language and symbols of science: a best-selling health guru explains that his brand of healing is grounded in quantum theory; half the population believes Earth is being visited by space aliens who have mastered faster-than-light travel; and educated people wear magnets in their shoes to draw energy from the Earth. This is pseudoscience."

"Modern civilization depends on science...James Smithson was well aware that knowledge should not be viewed as existing in isolated parts, but as a whole, each portion of which throws light on all the other, and that the tendency of all is to improve the human mind, and give it new sources of power and enjoyment...narrow minds think nothing of importance but their own favorite pursuit, but liberal views exclude no branch of science or literature, for they all contribute to sweeten, to adorn, and to embellish life...science is the pursuit above all which impresses us with the capacity of man for intellectual and moral progress and awakens the human intellect to aspiration for a higher condition of humanity."

"It is not so much knowledge of science that the public needs as a scientific worldview—an understanding that we live in an orderly universe, governed by physical laws that cannot be circumvented."

"America's astronauts have been left stranded in low-Earth orbit, like passengers waiting beside an abandoned stretch of track for a train that will never come, bypassed by the advance of science."

"Few scientists or inventors set out to commit fraud. In the beginning, most believe they have made a great discovery. But what happens when they finally realize that things are not behaving as they believed?"

"I came to realize that many people choose scientific beliefs the same way they choose to be Methodists, or Democrats, or Chicago Cubs fans. They judge science by how well it agrees with the way they want the world to be."

"Take from the air every aëroplane; from the roads every automobile; from the country every train; from the cities every electric light; from ships even wireless apparatus; from oceans all cables; from the land all wires; from shops all motors; from office buildings every elevator, telephone, and typewriter; let epidemics spread at will; let major surgery be impossible—all this and vastly more, the bondage of ignorance, where knowledge now makes us free, would be the terrible catastrophe if the tide of time should but ebb to the childhood days of men still living! ... Therefore, whoever desires progress and prosperity, whoever would advance humanity to a higher plane of civilization, must further the work of the scientist in every way he possibly can."

"So when I finished my Ph.D., in retrospect it's kind of hard to believe that I had the audacity to do what I am about to describe. But I sort of looked around and asked myself, "What's the most interesting remaining , and where can I go to work on it?" ... the problem ..."

"Much of the of the Universe is thought to reside in some as yet unidentified . This view is based on the analysis of trajectories of luminous ‘‘tracers’’ that map out the local potential, assuming that gravity is the only long ranged interaction between ordinary and dark matter. This assumption should be tested experimentally if possible. Laboratory tests of the can constrain (at an interesting level) any exotic coupling between ordinary and dark matter when analyzed as a test of the uniformity of towards the center of the Galaxy."

"Ground-based and s suffer from sources of image quality degradation that typically preclude achieving the . For 𝐷=10 m class telescopes at optical wavelengths (𝜆 ∼500), the typical achieved of around 1 for a celestial (absent correction) is about 100 times worse than the diffraction limit. A variety of factors contribute to this image degradation, including: • index of refraction variations in the , • “ground layer” or “boundary layer” due to the boundary condition of zero wind velocity at the Earth’s surface, • perturbations to due to local topography and structures, • turbulence within the enclosure, due to ambient and driven airflow through the slit and vents in the dome, • thermally driven air currents due to power dissipation on the telescope top end, and other locations, • turbulence and thermal currents in the vicinity of the primary mirror due to temperature differences between the mirror and the adjacent air, • tracking errors and vibrations in the , • wind-driven oscillations and motions of the mirror support systems, and • quasi-static s in the optical system."

"In my opinion the situation constitutes a crisis in fundamental physics that is every bit as profound as that which preceded the advent of quantum mechanics. ... Today, in the absence of a clear theoretical framework with relevant predictive power, the Dark Energy problem is best characterized as a data and discovery driven endeavor, spiced with interesting theoretical speculation."

"One should mention right at the start that one still does not understand whether quantum mechanics and special relativity are compatible at a fundamental level in our Minkowski four-space world. One generally assumes that this means finding a complete Yang-Mills gauge theory or the interaction of gauge fields with fermionic matter fields, the simplest form being quantum chromodynamics (QCD). Associated with this picture is the belief that the fundamental vector meson excitations are massive (as opposed to photons, which arise in the limiting case of an abelian gauge symmetry. The proof of the existence of a “mass gap” appears a necessary integral part of solving the entire puzzle. This question remains one of the deepest open issues in theoretical physics, as well as in mathematics. Basically the question remains: can one give a mathematical foundation to the theory of fields in four-dimensions? In other words, can do quantum mechanics and special relativity lie on the same footing as the classical physics of Newton, Maxwell, Einstein, or Schrödinger—all of which fits into a mathematical framework that we describe as the language of physics. This glaring gap in our fundamental knowledge even dwarfs questions of whether there are other more complicated and sophisticated approaches to physics—those that incorporate gravity, strings, or branes—for understanding their fundamental significance lies far in the future. In fact, one believes that stringy proposals, if they can be fully implemented, have limiting cases that appear as relativistic quantum fields, just as relativistic quantum fields describe non-relativistic quantum theory and classical physics in various limiting cases."

"Most physicists will remember Jim Faller for his contributions to ."

"At first sight, the problem of constructing a quantum theory of gravity sounds easy since there are no experimental constraints! The task is simply to find any theory which unifies general relativity and quantum theory. However, on second thought, the problem sounds extremely difficult. General relativity teaches us that gravity is just a manifestation of the curvature of space and time. So quantum gravity must involve the quantization of space and time, something we have no previous experience with. Surprisingly, even though there are no experimental constraints, this is a constraint on quantum gravity which was found in the early 1970’s by studying black holes. Motivated by the close analogy between the laws of black hole mechanics and ordinary thermodynamics, Bekenstein proposed that ..."

"... during the past 20–30 years, the subject of has—as a result of advances in measurement technologies—been transformed from a chiefly theoretical endeavor that explored beautiful theorems, involving the and equations, to an experimental science—a science that has come of age as one can now make real-time measurements at the levels at which geophysical happenings are taking place. And absolute gravimetry (along with very long baseline interferometry, global positioning satellites, satellite ranging, etc.) was and is contributing to this revolution."

"He was passionate about JILA and the future of JILA. He was a strong advocate for hiring [a leading researcher in ]. He had a great sense of the qualitative understanding of a lot of physics, especially . I remember talking to him about the design of an experiment and him having good suggestions. He was a big advocate for the instrument shop. I think part of it is because he admired those guys for building and designing things."

"Ten years ago, it was common (and correct) to distinguish the two main approaches to by saying that string theory ... was perturbative, and background dependent while the other approach ... was non-perturbative and background independent. In light of this, it is not surprising that most relativists were not interested in string theory. … One of the main things that has changed over the past decade is that we now know that string theory does not just involve strings. Higher (and lower) dimensional objects (called s) play an equally fundamental role. Using these branes, convincing evidence has been accumulated that all five of the perturbative string theories are just different limits of the same theory, called . (There is no agreement about what the M stands for.) There is yet another limit in which M theory reduces to eleven dimensional ."

"A hundred years ago our view of space and time was dramatically changed by the introduction of special relativity. Ten years after that, Einstein made spacetime dynamical in his general theory of relativity. It has long been expected that quantum gravity will require an even more radical change in our view of spacetime. String theory is a promising approach to a consistent quantum theory of gravity. In the past few decades a new picture of spacetime has been emerging from this theory. While this picture is far from complete, it is already clear that spacetime has many different features than it does in relativity."

"Determinations of the fit into the oftentimes-unappreciated area of physics called precision measurement—an area which includes precision measurements, and . The determination of big G—a measurement which on the surface appears deceptively simple—continues to be one of 's greatest challenges to the skills and cunning of s. In spite of the fact that, on the scale of the Universe, big G's effects are so large as to single-handedly hold everything together, on the scale of an individual research laboratory, big G's effects are so small that they go unnoticed…hidden in a background of much larger forces and noise sources. It is this ‘smallness’ that makes determining the precise value of this (seemingly unrelated to the rest of physics) fundamental constant so difficult."

"A few words to the young women: When you combine a career with raising a family, the family responsibilities generally rest more heavily on you than on your husband, and you may need to proceed more slowly with your career than you would without a family. This may have its good side in that you can save up some interesting and important things to do after your children have left the nest. However, the responsibilities can often be so heavy as to frustrate a woman's career, and a lack of suitable child-care facilities is a major roadblock. To me it is no mystery why there are not more women in leadership positions in science. It has been mentioned that I am the first woman to receive the Howard Vollum Award, and of course I am very proud to be chosen. But when it is no longer considered unusual for a woman to be so honored or to achieve a position of leadership in public life, then we women will know that we have made it."

"David Todd Wilkinson died on 5 September 2002 in Princeton, New Jersey, after having battled cancer for 17 years. His role in the measurements of the thermal (CMB) was key to the completion of the program of cosmological tests that began with Edwin Hubble’s discovery of the expanding universe in 1929."

"The Cosmic Background Explorer (COBE) satellite, under study by NASA since 1976, will map the spectrum and the angular distribution of diffuse radiation from the universe over the entire wavelength range from 1 micron to 1.3 cm. It carries three instruments: a set of differential s (DMR) at 23.5, 31.4, 53, and 90 , a far infrared absolute (FIRAS) covering 1 to 100 cm-1, and a covering 1 to 300 s. They will use the ideal space environment, a one year lifetime, and standard instrument techniques to achieve orders of magnitude improvements in sensitivity and accuracy, providing a fundamental data base for cosmology. The instruments are united by common purpose as well as similar environmental and orbital requirements. The data from all three experiments will be analyzed together, to distinguish nearby sources of radiation from the cosmologically interesting diffuse background radiations."

"The universe is filled with thermal radiation having a current temperature of 2.75 K. Originating in the very early universe, this radiation furnishes strong evidence that the Big Bang cosmology best describes our expanding universe from an incredibly hot, compacted early stage until now. The model can be used to extrapolate our physics backward in time to predict events whose effects might be observable in the 2.75 K radiation today. The spectrum and isotropy are being studied with sophisticated microwave radiometers on the ground, in balloons, and in satellites. The results are as predicted by the simple theory: the spectrum is that of a blackbody (to a few percent) and the radiation is isotropic (to 0.01 percent) except for a local effect due to our motion through the radiation."

"NASA’s Cosmic Background Explorer satellite mission, the COBE, laid the foundations for modern cosmology by measuring the spectrum and anisotropy of the and discovering the . ... The COBE observed the universe on the largest scales possible by mapping the cosmic microwave and infrared background radiation fields and determining their spectra. It produced conclusive evidence that the hot Big Bang theory of the early universe is correct, showed that the early universe was very uniform but not perfectly so, and that the total luminosity of post–Big Bang objects is twice as great as previously believed."

"… the technical question was, “Is the Big Bang the right story? Is the expanding universe the right story?” And there are a lot of sub-questions in that. If it is the right story, then how did the galaxies come? Where did they come from? Because it seemed quite mysterious. People were just beginning to realize that there was a structure that had been seen in the maps of where the galaxies are located, and that we had no clue what made that happen. So what is there to measure? Well, there’s not very many things to measure. You can measure the galaxies or you can look for this cosmic background radiation. And if you could measure it, it would tell you something that you never knew before."

"... Are we thinking about the wrong? Are we thinking about quantum field theory wrong? Are there particles at the Large Hadron Collider that are hiding from us? ... It's true that the Large Hadron Collider has vast data sets. And when you have a gigantic amount of data, if you don't ask exactly the right question, you might not see what's actually in there. So, we have to be very thoughtful about all the different questions that we should ask of this data."