Astronomers From The United States

"But my reasons for taking this less-traveled road were many. One is the inevitable thrill of discovery when you wander into new areas. More importantly, you also avoid the danger of being too comfortable in too narrow a niche. I truly believe the sayings that there is no hope for the satisfied man and that without fear there is no learning. Entering a new field with a degree in another is not unlike Lewis and Clark walking into the camp of the Mandans. You are not one of them. They distrust you. Your degree means nothing and your name is not recognized. You have to learn it all from scratch, earn their respect, and learn a lot on your own. But I also think that many of the most significant discoveries in science will be found not in but between the rigid boundaries of the disciplines: the terra incognita where much remains to be learned. It's not a place that's hidebound by practice and ritual. I have always tried to keep moving between fields of study and it shows up, I think, in my vitae."

"I guess the other thing I find a little bit on the downside is that all the papers can now be downloaded off the web. That bothers me a little because I think in the old days, when you picked up the journal, you kind of looked at everything on the back of it, the titles, and there were things you didn’t know that much about or that you had a faint connection with, and maybe you looked at the paper; maybe you read the abstract at least. Nowadays, you just dial up what you’re interested in; you don’t see any of the rest of the literature. I do worry over this kind of compartmentalization of astronomy, which I think has gotten to be a bit out of hand..."

"Self-study, in a sense of learning by yourself without anybody teaching you anything, has an enormous value."

"Only by doing the best we can with the very best that an era offers, do we find the way to do better in the future."

"The amazing thing is that every atom in your body came from a star that exploded, and the atoms in your left hand probably came from a different star than your right hand. It really is the most poetic thing I know about physics. You are all stardust. You couldn’t be here if stars hadn’t exploded because the elements—the carbon, nitrogen, oxygen, iron, all the things that matter for evolution—weren’t created at the beginning of time. They were created in the nuclear furnaces of stars, and the only way they could get... into your body is if these stars were kind enough to explode. So, forget Jesus. The stars died so that you could be here today."

"... we're here because of an environmental accident if there is a multiverse and if the laws of physics are different in the different regions ..."

"We only see shadows of reality. We shouldn't expect those shadows to behave sensibly."

"It is a shame when nonsense can substitute for fact with impunity."

"There's a loophole if you weigh galaxies and clusters because you're weighing the total amount of energy around galaxies. What if there's energy where galaxies aren't? What is where galaxies aren't? Nothing."

"[W]e can weigh systems of galaxies. The largest bound objects in the universe are called clusters of galaxies. They're maybe ten million light years across. ...We weigh them using gravity because Einstein told us that mass curves space, and we can... use those large clusters as lenses—if there's a light source behind a cluster the light from it can come around and be lensed... and we've weighed these systems and we've found that there's only 30% of the mass needed to make a flat universe... Theorists like me knew that the universe was flat, because it's the only mathematically beautiful universe... but here these observers kept coming up with only 30% of the stuff needed... But then, what we've discovered... is that the universe actually is flat and the rest of the 70% of the energy of the flat universe comes from the energy of nothing."

"[W]hy presumes purpose... But what if there isn't purpose? Whenever we say why we really mean how."

"[Y]ou... may say, "Well look, we've got no space, no time, no particles, no radiation. That's a pretty good approximation of nothing, but there's still the laws. Who created the laws? And... what we've discovered... in the last ten years or so, and... this is speculative, but it's based on everything we know of in particle physics... It's quite reasonable to suspect that even the laws themselves came into existence when our universe came into existence... There could be many different universes and in each one of them the laws of physics are different. They spontaneously arise when the universe arises."

"[W]hen you apply quantum mechanics to gravity, then even space itself can pop into existence from nothing. Space and time can spontaneously pop into existence... Whole universes can pop into existence and most of them will disappear in a time scale so short you wouldn't know about it. The ones that can survive for a long time have zero total energy..."

"Now some people say, "Well, if there's virtual particles there it's really not nothing," but there are no real particles. You try and measure things there, there's nothing, but those virtual particles can give space energy and in fact we've discovered to our great surprise—it won the Nobel prize two years ago—that empty space has energy, and if you put energy in empty space, then it's really strange because it's not like the normal energy... it's not gravitationally attractive, it's actually repulsive, and we've discovered the expansion of the universe is not slowing down like any sensible universe should do. It's actually speeding up... because it's dominated by the energy of empty space."

"[O]ne of the great things about science is it forces us to refine our idea of what's common sense. It forces us to have our beliefs conform to the evidence of reality rather than the other way around. The universe may not be like we'd like it to be, but it doesn't really care."

"The energy of every galaxy—all the galaxies are moving away from us at, Hubble discovered that in 1929... If you measure their speed and then you work our the attraction the two add up to precisely zero. An amazing discovery that confirms this notion that, not only is the universe flat and mathematically beautiful, but begins to give us an inkling that maybe, maybe, maybe we could come from nothing."

"But what we've discovered is that, in fact... the total energy of the universe could be zero, which is a first clue that maybe it could come from nothing. ...In physics, ...once you include gravity, there's positive energy and negative energy, and our universe appears as if its total energy could be precisely zero, which is the first hint that maybe it could come from nothing. That, and the great discovery... that namely empty space, you take a region of space, get rid of all the particles and all the radiation ...so there's nothing there. That empty space weighs something, and we don't understand why."

"Richard Feynman used to go up to people all the time and he'd say, "You won't believe what happened to me today. You won't believe what happened to me." And people would say "What?" And he'd say, "Absolutely nothing". Because we humans believe that everything that happens to us is special, and significant. And that—and... Carl Sagan wrote beautifully about that in Demon-Haunted World—that is much of the source of religion. OK? Everything that happens is unusual, and I expect that the likelihood that Richard and I ever would've met—if you think about all the variables, the probability that we were in the same place at the same time, ate breakfast at the same... Whatever. It's zero. Every event that happens has small probability... but it happens, and then when it happens; if it's weird, if you dream one million nights and it's nonsense, but one night you dream that your friend is gonna break his leg and the next day he breaks his arm. You think, "ah." ...So the [real] thing that physics tell us about the universe is it's big, rare events happen all the time—including life—and that doesn't mean it's special."

"What's going to happen in the far future? Remember a hundred years ago we thought we lived into static eternal Universe. What will the future bring? The amazing thing is, for civilizations that live in a far future, what will they see? Well, the Universe is accelerating. That means all the distant galaxies are getting carried away from us, and eventually they'll move away from us faster than the speed of light. It's allowed in General relativity. They will disappear. The longer we wait, the less we will see. In a hundred billion years any observers evolving on stars around [us]... and there will be stars just like our Sun in 100 billion years. Any observers and civilizations... evolving around those stars will see nothing except for our Galaxy, which is exactly the picture they had in 1915. All evidence of the Hubble expansion will disappear. Why? Because we won't see other galaxies moving apart from us. So they will have no evidence, in fact, of Big Bang. They won't see the Hubble expansion. They won't even know about dark energy, and I won't go into that. They won't know about the cosmic microwave background - it will disappear too. It will redshift away, and it turns out for fancy reasons: there is a plasma in our Galaxy and when the Universe is 50 times its present age the microwave background won't able to propagate in our Galaxy. All evidence of the Big Bang will have disappeared, and those scientists will discover quantum mechanics, discover relativity, discover evolution, discover all the basic principles of science that we understand today, use the best observations they can do with the best telescopes they will build and they will derive a picture of the Universe which is completely wrong. They will derive a picture of the Universe as being one Galaxy surrounded by empty space that's static and eternal. Falsifiable science will produce the wrong answer. In fact, I want to end with the good news. We live in a very special time, the only time we can observationally verify that we live in a very special time."

"The Universe must be flat. Why? Well, there is two reasons. There's the one I normally say, which is: it's the only mathematically beautiful universe. Which is true, but there's another reason I don't usually... talk about but I'll talk about here. It turns out that in a flat universe the total energy of the universe is precisely zero because gravity can have negative energy. So the negative energy of gravity balances out the positive energy of matter. What's so beautiful about a universe with total energy zero? Well, only such a universe can begin from nothing, and that is remarkable because the laws of physics allow a universe to begin from nothing. You don't need a Deity. You have nothing: zero total energy, and quantum fluctuations can produce a universe. So, if the Universe isn't flat we're worried, because then you've got energy at... the very beginning of Time."

"Science is empirical: knowing the answer is nothing. Testing your knowledge means everything."

"Theorists always know the answer. They're just sometimes right."

"The other thing people don't realise about science which differentiates it from religion is that, the most exciting thing about being a scientist is not knowing and being wrong. Because that means there is a lot left to learn."

"Science simply forces us to revise what is sensible to accommodate the universe, rather than vice versa."

"If you have nothing in quantum mechanics, you will always have something."

"Now, since the time of Newton there had been a debate about whether light was a wave---that is, a traveling disturbance in some background medium---or a particle, which travels regardless of the presence of a background medium. The observation of Maxwell that electromagnetic waves must exist and that their speed was identical to that of light ended the debate: light was an electromagnetic wave."

"There is a maxim about the universe which I always tell my students: That which is not explicitly forbidden is guaranteed to occur."

"My area of research is something that in all fairness has no practical usability whatsoever and the thing is I'm often asked to apologize for that. It is interesting to me that people ask 'what's the point of doing that if it's not useful?' But they never ask that, or do they very rarely ask that about art or literature or music. Those things are not gonna produce a better toaster."

"A theory can never be proven absolutely true, therefore there is no end to scientific endeavor. A true scientific theory is always open to be disproved, and the burden of proof is continually placed on the scientist."

"If our astronomer be judged by the original contributions which, under existing adverse circumstances, he actually did make to astronomy and mathematics, then it must be admitted that he can not be placed in the foremost rank of astronomers then living. Friends will judge him by what he might have done; the world at large will judge him by what he actually accomplished. Our greatest indebtedness to Rittenhouse lies not in the original contributions he made to science, but rather in the interest which he aroused in astronomical pursuits, and in the diffusion of scientific knowledge in the New World which resulted from his efforts."

"Only two transits of Venus had been observed before his time, and of these, the first, in 1639, had been seen by only two persons. These transits happen so seldom that there cannot be more than two in one century, and in some centuries none at all. But the transits of Venus are the best means we have for determining the parallax of the sun. ...The observations were a success and established for Rittenhonse the reputation of an exact and careful astronomer. ...During the transit Rittenhouse saw one phenomenon which escaped the notice of all other astronomers. When the planet had advanced about half of its [Venus'] diameter upon the sun, that part of the edge of the planet which was off the sun's disc appeared illuminated, so that the outline of the entire planet could be seen. But a complete circle of light around Venus would indicate that more than half of Venus is illuminated. This can happen... only when the rays of light are refracted by an atmosphere. Hence... Venus is surrounded, like the earth, by an atmosphere. But this appearance of a ring of light was not confirmed by other astronomers, and the statement of Rittenhouse excited no attention for nearly a century, until his observation was at last confirmed by other astronomers."

"As a mechanic, Rittenhouse became celebrated for the extreme exactness and finish of his workmanship. Especially celebrated were his chronometer clocks. It was while thus engaged in the manufacture of clocks that he planned and executed an instrument which brought into play both his mechanical and mathematical skill. ...the orrery. It was, indeed, intended to be a sort of a perpetual astronomical almanac, in which the results, instead of being exhibited in tables, were to be actually exhibited to the eye. His orrery greatly exceeded all others in precision. It attracted very general attention among well informed persons... There arose a lively competition between different colleges in this country for the possession of this orrery."

"His invention, whatever it may have been, was not of sufficient importance to deserve the name of an "invention of fluxions." If Rittenhouse actually made an invention of such transcending magnitude before the age of twenty, and at a time when he had hardly begun his scientific studies, how is it that he made not the slightest approach to any similar discovery during the forty-four years of his maturer life? Though always a passionate lover of scientific pursuits, he made no original contributions whatever to the science of pure mathematics. Science is indebteded to him chiefly for his orreries and the observations of the transit of Venus. ...the alleged invention of fluxions was little more than a "rumor set afloat by idle gossip." It serves to show us, however, in what unbounded admiration he was held by his countrymen."

"The most noted mathematician and astronomer of early times [in the U.S.] was not a professor in a college, nor had he been trained within college walls. We have reference to David Rittonhouse."

"Among the books he inherited from his uncle was an English translation of the "Principia" of Newton. Such was the progress which he made in mathematical knowledge, although now destitute of any aid, that he was enabled to accomplish the perusal of this work, for the proper understanding of which so much acquaintance with geometry and algebra is necessary, before he had attained his nineteenth year. Newton, as is well known, from deference to the practice of the ancient philosophers, adopts in this work the synthetic method of demonstration, and gives no clue to the analytic process by which the truth of his propositions was first discovered by him. Unlike the English followers of this distinguished philosopher, who contented themselves, for a time, with following implicitly in the path of geometric demonstration, which he had thus pointed out, Rittenhouse applied himself to search for an instrument, which might be applied to the purpose of similar discoveries, and in his researches attained the principles of the method of fluxions. So ignorant was he of the progress which this calculus had made, and of the discussions in relation to its invention and improvement, that he for a time considered it as a new discovery of his own. In this impression, however, he could not have long continued; as he made, in his nineteenth year, an acquaintance who was well qualified to set him right in this important point."

"It was during the residence of our ingenious philosopher with his father in the country that he made himself master of Sir Isaac Newton's Principia, which he read in the English translation of Mr. Motte. It was here, likewise, he became acquainted with the science of fluxions; of which sublime invention he believed himself, for a while, to be the author, nor did he know for some years afterwards that a contest had been carried on between Sir Isaac Newton and Leibnitz for the honor of the great and useful discovery. What a mind was here! Without literary friends or society, and with but two or three books, he became, before he had reached his four and twentieth year, the rival of two of the greatest mathematicians in Europe."

"The year 1775 opened with a project intended to bring the abilities of Rittenhouse more effectually into the service of science. The Philosophical Society addressed the colonial legislature of Pennsylvania, praying it to establish a public observatory, and commit it to the care of Rittenhouse. Had the circumstances of the times permitted this project to be carried into effect, it would have enabled him to occupy a great space in the history of astronomy. He had already shown himself the equal, in point of learning and skill as an observer, to any practical astronomer then living; nothing was wanting to make him rank with the Flamsteads, the Halleys, and the Maskelynes, but that he should be permitted to devote his whole mind to this pursuit, and be furnished with those instruments and accommodations, for which no private fortune will suffice. Other men might have been found as well, nay, better qualified for the political pursuits and public offices in which it became his fate to spend the rest of his life; but America has never yet produced any individual who has manifested so great a capacity for extending the domain of practical astronomy. To arrange the details of a disorganized and depreciating currency, to collect and disburse a scanty and ill-paid revenue, were thereafter to be the pursuits of our philosopher; and he was to expend upon the estimates and returns of the tax-gatherer those powers of mind which were capable of grasping, and that mechanical skill which sufficed to imitate, the vast mechanism of the universe."

"I do not design a machine which will give the ignorant in astronomy a just view of the solar system, but would rather astonish the skilful and curious observer by a most accurate correspondence between the situations and motions of our little representatives of our heavenly bodies and the situations and motions of those bodies themselves. I would have my orrery really useful by making it capable of informing us truly of the astronomical phenomena for any particular point of time, which I do not find that any orrery yet made can do."

"I have no health for a soldier, and as I have no expectation of serving my country in that way, I am spending my time in the old trifling manner, and am so taken with optics, that I do not know whether, if the enemy should invade this part of the country, as Archimedes was slain while making geometrical figures on the sand, so I should die making a telescope."

"Before the nineteenth century, writers on education portayed the "improvement of mind" as an activity mainly suited to gentlemen. ...both Thomas Jefferson and Benjamin Rush had venerated David Rittenhouse as an example of how arduous philosophical investigation might elevate the child of humble parents. But Jefferson and Rush tagged Rittenhouse as a genius, and hence untypical, and each employed Rittenhouse as ammunition in a debate among educated gentlemen. Jefferson invoked Rittenhouse in his Notes on the State of Virginia, a book he wrote to disabuse French philosophes of the notion that all specied degenerated in the New World; Rush used his eulogy of Rittenhouse before the select audience of the American Philosophical Society to ridicule colleges for requiring students to learn the ancient languages."

"'America had not yet produced one good poet.' When we shall have existed as a people as long as the Greeks did before they produced a Homer, the Romans a Virgil, the French a Racine and Voltaire, the English a Shakespeare and Milton, should this reproach be still true, we will inquire from what unfriendly causes it has proceeded, that the other countries of Europe and quarters of the earth shall not have inscribed any name in the roll of poets. But neither has America produced 'one able mathematician, one man of genius in a single art or a single science.' In war we have produced a Washington, whose memory will be adored while liberty shall have votaries, whose name shall triumph over time, and will in future ages assume its just station among the most celebrated worthies of the world, when that wretched philosophy shall be forgotten which would have arranged him among the degeneracies of nature. In physics we have produced a Franklin, than whom no one of the present age has made more important discoveries, nor has enriched philosophy with more, or more ingenious solutions of the phenomena of nature. We have supposed Mr. Rittenhouse second to no astronomer living: that in genius he must be the first, because he is self-taught. As an artist he has exhibited as great a proof of mechanical genius as the world has ever produced. He has not indeed made a world; but he has by imitation approached nearer its Maker than any man who has lived from the creation to this day."

"See the sage Rittenhonse, with ardent eye, Lift the long tube and pierce the starry sky; Clear in his view the circling systems roll, And broader splendours gild the central pole. He marks what laws th' eccentric wand'rers bind, Copies Creation in his forming mind, And bids, beneath his hand, in semblance rise, With mimic orbs, the labours of the skies. There wond'ring crowds with raptur'd eye behold The spangled heav'ns their mystic maze unfold; While each glad sage his splendid hall shall grace, With all the spheres that cleave th' ethereal space."

"The direct tendency of (Astronomy) is to dilate the heart with universal benevolence, and to enlarge its views."

"The way of truth is along the path of intellectual sincerity."

"There was more known, but always more to be known. Yes, she thought, and the unknown can masquerade as the unknowable."

"“He was guilty of the heresy of humanism.” “How can that be heresy?” “The narcissistic devotion to things human? ‘Man is the measure of all things?’ Easily.”"

"An animal that liked abstractions? Maybe that wasn’t all that bad a definition of being human."

"Quantum uncertainty, chaos—these forever screen precise knowledge of the future from our eyes."

"“The price of such seeing will be death,” Seeker said quietly. She blinked. “We’ve done fine so far.” “A numerical series can have many terms yet be finite.”"

"When you know nothing, you are free to hope."