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Category Archives: Quantum Physics

What Is String Theory? – Worldatlas.com

Posted: July 7, 2022 at 9:04 am

Physics is upheld by two pillars: the physics of relativity and quantum mechanics. Relativity, which was first proposed by Albert Einstein. It explains the universe on its largest scales, such as gravity and the speed of light. Quantum mechanics is the very opposite, being the science of the smallest scales, such as atoms and subatomic particles. Together, relativity and quantum mechanics can explain the very large and the very small. However, despite both upholding all of what we know about physics, relativity and quantum mechanics dont work well together. In fact, scientists have been unable to combine the two theories into a single, unified theory of everything.

Relativity and quantum mechanics are like a dog and a cat constantly fighting, unable to find any compromise. It may not seem overly important to combine the two pillars of physics into one. After all, separately, relativity and quantum mechanics can explain most of the universe. However, having two separate laws that govern the universe has its problems.

For example, imagine there were two types of streets, and the type defines the rules of driving. Some streets have either one type or the other, so the rules are pretty simple. However, other streets fit the definition of both types, so which driving rules apply to them? Like having two completely different rules of the road, the inability to combine quantum mechanics and relativity creates chaos when trying to understand our universe. Interestingly, there are some potential theories out there that combine the two pillars of physics, the most famous of which is string theory.

According to string theory, if you were to look inside any fundamental particle, such as an electron, you would find a tiny vibrating string of energy. When the string vibrates, the energy it generates creates a particle such as an electron. In string theory, fundamental particles can be thought of as energy vibrations. Furthermore, string theory predicts the existence of eleven dimensions. The reason we dont see these dimensions in our everyday lives is because theyre simply too small to detect. However, the extra dimensions play a vital role. The configuration of the dimensions determines how a string vibrates, and hence what particle is made. The strings vibrate in eleven dimensions, and the frequency at which the string vibrates is dependent upon how the string is oriented within the eleven dimensions. Different frequencies of vibrations generate different particles.

The reason why string theory is a potential theory of everything is because it predicts that all forms of matter are made up of strings, and thus everything is really made up of the same stuff. Whether its the gravitational force or the electromagnetic force, all of it relates back to vibrating strings. It should be noted, however, that no evidence has been found to support string theory. None of its predictions have been verified through either experiment or observation. As of yet, its more of a mathematical theory rather than one of physics.

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Two Professors Embarked on an Extended Conversation During the Pandemic – Columbia University

Posted: at 9:04 am

Q. Can you give some examples from the book of the lessons that a catastrophe can teach about the future, and about how to live and face death?

A. Jack and I have spent our lives reading, teaching, and writing about religion, philosophy, and art. In our conversation in the book, we explore the lessons of two major themesdeath and friendshipthat great writers and artists of the past can offer us today.

Suffering life-threatening disease is a humbling experience that reminds you how fragile life is. Acknowledging this vulnerability and accepting deaths inevitability can be liberating, and it opens you to empathetic relationships with other people.

Genuine friendship is a rare gift. Isolation and solitude are not the sameisolation separates, solitude connects. Though often alone and separated by a continent during those long months, our epistolary conversation deepened our friendship.

Q. Do things seem less bleak now than they didwhile you were working on the book?

A. Though we knew the pandemic would be devastating, we never anticipated that many millions of people globally would contract the disease, and over one million would die in the U.S. This virus is smart and adapts to human intervention faster than humans adapt to it. We started writing about a biological virus, but quickly realized that the body politic and global media are also infected with deadly viruses. The different strains of these viruses are co-evolving at an accelerating rate. Given the political paralysis in this country, and the growing instability of the global financial and political situation, things are so much worse now that it is hard to be hopeful. Hopelessness, however, is a luxury we cannot afford.

Q. What have you read lately that you would recommend, and why?

A. Suzanne Simards Finding the Mother Tree: Discovering the Wisdom of the Forest is a well-researched book about plant intelligence that makes you rethink the relationship between human beings and the natural world.

Lee Smolin, Time Reborn: From the Crisis in Physics to the Future of the Universe. A provocative reinterpretation of the most fundamental dimension of life.

Matt Haig, The Midnight Library. An inventive novel of regrets framed in terms of quantum physics and multiple worlds theory.

Q. What's on your night stand now?

A. Since I tend to read all day every day, I dont keep books on my night stand, but the books beside my desk are: Carlo Rovelli, Reality Is Not What It Seems: The Journey to Quantum Gravity; David Kaiser, How the Hippies Saved Physics; and a novel, Olga Ravns The Employees.

Q. What do you read when you're working on a book, and what kind of reading do you avoid while writing?

A. After months, sometimes years, of reading, I will suddenly see the book; its a strange experience. At that point, a book more or less writes itself. When in this zone, I read nothing else because reading more can break my rhythm and make me lose the thread.

Q. Any interesting summer plans?

A. I live in the Berkshire Mountains of Massachusetts. This summer I am looking forward to a welcome relief from COVID summersmy children and grandchildren will be returning home. In addition, I have created a philosophical sculpture garden, which requires lots of work. I am beginning the design of a new sculpture.

Q. You're hosting a dinner party. Which three academics or scholars, dead or alive, would you invite, and why?

A. If I could time travel, I would return to Jena in Germany on New Years Eve 1803, and throw a dinner party for Immanuel Kant, Johann Wolfgang von Goethe, Friedrich Schiller, Friedrich Schelling, Caroline Schelling, Friedrich Schleiermacher, Friedrich Holderlin, Alexander von Humboldt, the Schlegel brothers, Dorothea von Schlegel, and, above all, G.W.F. Hegel.

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Noam Chomsky and Andrea Moro on the Limits of Our Comprehension – The MIT Press Reader

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An excerpt from Chomsky and Moros new book The Secrets of Words.

By: Noam Chomsky and Andrea Moro

In their new book The Secrets of Words, influential linguist Noam Chomsky and his longtime colleague Andrea Moro have a wide-ranging conversation, touching on such topics as language and linguistics, the history of science, and the relation between language and the brain. Moro draws Chomsky out on todays misplaced euphoria about artificial intelligence (Chomsky sees lots of hype and propaganda coming from Silicon Valley), the study of the brain (Chomsky points out that findings from brain studies in the 1950s never made it into that eras psychology), and language acquisition by children. Chomsky in turn invites Moro to describe his own experiments, which proved that there exist impossible languages for the brain, languages that show surprising properties and reveal unexpected secrets of the human mind.

Chomsky once said, It is important to learn to be surprised by simple facts an expression of yours that has represented a fundamental turning point in my own personal life, says Moro. This is something of a theme in The Secrets of Words. Another theme, explored in the excerpt from the book featured below, is that not everything can be known; there may be permanent mysteries, about language and other matters.

Andrea Moro: There is something you wrote, back when you gave the Managua Lectures, and actually you rephrased it in a very articulated fashion in the talk you gave at the Vatican. It is an expression of yours that has represented a fundamental turning point in my own personal life, but also I am sure for all the students who heard it. You once said: It is important to learn to be surprised by simple facts. Considering it carefully and analyzing it word by word, this sentence contains at least four different foci, so to speak: first, it makes note of the importance of the thought expressed (it is important); second, it refers to a learning process, an effort rather than to a personal inherited talent (to learn), and by doing so it emphasizes the importance of the responsibility to teach; third, it refers to the sense of wonder and curiosity as the very engine of discovery, and to an awareness of the complexity of the world that is, an observation that goes back to Plato and the origin of philosophy (to be surprised); finally, fourth, arguably the most striking and innovative observation, it states that simple facts make a difference (by simple facts).

The sudden awareness of something that calls for an explanation, once the fog of habit has lifted, seems to be the real stuff revolutions sparkles are made of: from Newtons legendary falling apple to Einsteins elevator, from Plancks black body problem to Mendels pea plants, the real force comes from asking questions about what all of a sudden doesnt seem to be obvious. Of course, it could be that one is exposed to a certain fact by chance, but, as Pasteur once put it, In the fields of observation chance favors only the prepared mind, and this is why we need to learn how to be surprised.

Actually, certain simple facts can be visible to the minds eye rather than to our direct vision. Owen Gingerich once made me realize how Galileo reached the conclusion that all bodies fall to the Earth at the same speed even if they have different weight, besides the obvious restrictions due to their shape: Galileo never amused himself by throwing objects from the Tower of Pisa. Instead, he reflected that if a heavy object fell faster than a light one, then when the two objects are tied together we would face a paradox: The lighter object should slow down the heavier one, but together they should fall faster since their total weight is greater than that of the heavier object on its own. Galileo, surprised by this simple mental fact, came to the fundamental conclusion that the only possibility is that these two objects had to fall at the same speed and then, generalizing it, that all objects fall at the same speed (disregarding friction with the air due to their shape). And this without having to climb the tower other than to enjoy the panorama.

The sudden awareness of something that calls for an explanation, once the fog of habit has lifted, seems to be the real stuff revolutions sparkles are made of.

And the second thing I would like to highlight from your synthesis: At a certain point you said that it is impossible to build a machine that talks. Obviously, I cannot but agree, but theres one important thing that I want to emphasize: There is a fundamental distinction between simulating and comprehending the functioning (of a brain but also of any other organ or capacity). It is, of course, very useful to have tools, which we can interact with by speaking, but it is certainly clear that those simulations cannot be used to understand what really goes on in the brain of a child when they grow and acquire their grammar. Of course, we can always stretch words so that they become felicitous to mean something different from what they used to mean. This reminds me of the answer Alan Turing gave to those who repeatedly asked him if one day machines could think. We can read his own words and substitute think with talk, which I think leaves the essence of Turings idea valid:

I propose to consider the question, Can machines think? This should begin with definitions of the meaning of the terms machine and think. The definitions might be framed so as to reflect so far as possible the normal use of the words, but this attitude is dangerous. If the meaning of the words machine and think are to be found by examining how they are commonly used it is difficult to escape the conclusion that the meaning and the answer to the question, Can machines think? is to be sought in a statistical survey such as a Gallup poll. But this is absurd. . . . The original question, Can machines think? I believe to be too meaningless to deserve discussion. Nevertheless I believe that at the end of the century the use of words and general educated opinion will have altered so much that one will be able to speak of machines thinking without expecting to be contradicted.

There is one question I would like to ask you. The way that you have depicted the relationship between chemistry and physics in the history of science allows us to reflect on the relationship between linguistics and neuroscience. My personal view, which doesnt count, obviously [laughs], and which is why I want to ask you, is that linguistics cannot be, must not be ancillary to what we currently know about our brain; but if anything, we have to change and grow toward, perhaps, a unification provided that we dare to use the term mystery in the way that you used it. In other words, it is not out of the question that humans may never end up understanding creativity in language, namely the capacity to express a verbal thought independently of ones physical environment. Indeed, it could well be that we must just stop short of the boundaries of Babel, that is, the limits of variation that may affect human languages as given independently of experience. Equivalently, one could consider the boundaries of Babel as the infants stem mind, or stem brain, that is, the potentiality to acquire any language within a certain amount of time since birth. The discovery of this amazing link between language structure and the brain is so revolutionary that it can be expressed by reversing the 2,000-year-old traditional perspective and arriving at the surprising conclusion that its flesh that became logos, not vice versa. I would like you to comment a little on this.

Noam Chomsky: Im kind of a minority. The two of us are a minority. [Moro laughs.] There may indeed be a mystery. Lets take a look at, say, rats, or some other organism. You can train a rat to run pretty complicated mazes. Youre never going to train a rat to run a prime number maze a maze that says, turn right at every prime number. The reason is that the rat just doesnt have that concept. And theres no way to give it that concept. Its out of the conceptual range of the rat. Thats true of every organism. Why shouldnt it be true of us? I mean, are we some kind of angels? Why shouldnt we have the same basic nature as other organisms? In fact, its very hard to think how we cannot be like them. Take our physical capacities. I mean, take our capacity to run 100 meters. We have that capacity because we cannot fly. The ability to do something entails the lack of ability to do something else. I mean, we have the ability because we are somehow constructed so that we can do it. But that same design thats enabling us to do one thing is preventing us from doing something else. Thats true of every domain of existence. Why shouldnt it be true of cognition? Were capable of developing humans, not me humans are capable of developing, say, advanced quantum theory, based on certain properties of their mind, and those very same properties may be preventing them from doing something else. In fact, I think we have examples of this; plausible examples. Take the crucial moment in science when scientists abandoned the hope for getting to an intelligible world. That was discussed at the time.

It is not out of the question that humans may never end up understanding creativity in language.

David Hume, a great philosopher, in his History of England he wrote a huge history of England theres a chapter devoted to Isaac Newton, a full chapter. He describes Newton as, you know, the greatest mind that ever existed, and so on and so forth. He said Newtons great achievement was to draw the veil away from some of the mysteries of nature namely, his theory of universal gravitation and so on but to leave other mysteries hidden in ways we will never understand. Referring to: Whats the world like? Well never understand it. He left that as a permanent mystery. Well, as far as we know, he was right.

And there are other perhaps permanent mysteries. So, for example, Descartes, and others, when they were considering that mind is separate from body notice that that theory fell apart because the theory of body was wrong; but the theory of mind may well have been right. But one of the things that they were concerned with was voluntary action. You decide to lift your finger. Nobody knows how that is possible; to this day we havent a clue. The scientists who work on voluntary motion one of them is Emilio Bizzi, hes one of MITs great scientists, one of the leading scientists who works on voluntary motion he and his associate Robert Ajemian recently wrote a state-of-the-art article for the journal of the American Academy of Arts and Sciences in which they describe what has been discovered about voluntary motion. They say theyll put the outcome fancifully. Its as if were coming to understand the puppet and the strings, but we know nothing about the puppeteer. That remains as much a mystery as it has been since classical Greece. Not an inch of progress; nothing. Well, maybe thats another permanent mystery.

There are a lot of arguments saying, Oh, it cant be true. Everythings deterministic, and so on. All sorts of claims. Nobody truly believes it, including those who present reasons (two thermostats might be hooked up to interact, but they dont take the trouble to work out reasons). Science doesnt tell us anything about it. Science tells us it doesnt fall within science, as currently understood. Science deals with things that are determined or random. That was understood in the 17th century. Its still true today. You have a science of events that are random, of things that are determined; you have no science of voluntary action. Just as you have no science of the creativity of language. Similar thing. Are they permanent mysteries? Could be. Could be that its just something that well never comprehend.

Something similar might hold for some aspects of consciousness. What does it mean for me to look at the background that I see here and see something red? Whats my feeling of red? You can describe what the sensory organs are doing, whats going on in the brain, but it doesnt capture the essence of seeing something red. Will we ever capture it? Maybe not. Its just something thats beyond our cognitive capacities. But that shouldnt really surprise us; we are organic creatures. Its a possibility.

So maybe the best that we can do is what science did after Newton: Construct intelligible theories. Try to construct the best theory we can about consciousness or voluntary action or the creative use of language, or whatever were talking about. The miracle that so amazed Galileo and Arnauld and still amazes me, I cant understand it how can we, with a few symbols, convey to others the inner workings of our mind? Thats something to really be surprised about, and puzzled by. And we have some grasp of it, but not a lot.

When I started working on the history of linguistics which had been totally forgotten; nobody knew about it I discovered all sorts of things. One of the things I came across was Wilhelm von Humboldts very interesting work. One part of it that has since become famous is his statement that language makes infinite use of finite means. Its often thought that we have answered that question with Turing computability and generative grammar, but we havent. He was talking about infinite use, not the generative capacity. Yes, we can understand the generation of the expressions that we use, but we dont understand how we use them. Why do we decide to say this and not something else? In our normal interactions, why do we convey the inner workings of our minds to others in a particular way? Nobody understands that. So, the infinite use of language remains a mystery, as it always has. Humboldts aphorism is constantly quoted, but the depth of the problem it formulates is not always recognized.

Noam Chomsky is Institute Professor and Professor of Linguistics Emeritus at MIT and Laureate Professor in the Department of Linguistics at the University of Arizona, where he is also the Agnese Nelms Haury Chair in the Agnese Nelms Haury Program in Environment and Social Justice. He is the author of many influential books on linguistics, including Aspects of the Theory of Syntax and The Minimalist Program.

Andrea Moro is Professor of General Linguistics at the Institute for Advanced Study (IUSS) in Pavia, Italy. He is the author of Impossible Languages, The Boundaries of Babel, A Brief History of the Verb To Be, and other books.

Chomsky and Moro are co-authors of The Secrets of Words, from which this article is excerpted.

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Rugby league, quantum physics and the theory of everything – The Roar

Posted: July 4, 2022 at 11:49 pm

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Rugby league and quantum physics are both complex and mysterious, and after a lifetime spent studying both I have come to the conclusion Ill never fully understand either.

Its a well known fact that rugby league isnt rocket science, but there are startling similarities between quantum physics and rugby league.

Quantum physics is humans trying to simply explain nature at its most basic level, while rugby league is simply human nature at its most basic level.

There are many links between the two fields. In 2011, the Higgs particle was experimentally confirmed, and just a few months later Ray Higgs was confirmed in the Parramatta Hall of Fame. Surely this was no coincidence.

Quantum physics tells us that fundamental particles can only exist in certain states. This is very similar to how rugby league can only exist in certain states.

Until recently, the Standard Model of Physics contained 16 elementary particles. With the addition of the Higgs there are now 17. This is the main reason the Dolphins have been added to the competition.

Wayne Bennett will be the first coach of the Dolphins. (Photo by Bradley Kanaris/Getty Images)

Just like the universe itself, the Australian rugby league universe was once concentrated in one small place, but is expanding even as we speak.

Whether you are talking rugby league or quantum physics, I think everyone agrees that the role of the observer is critical.

Schrodingers wave function tells us that every pass is both backward and forward until it is observed by the referee. At this point the wave function collapses. In much the same way we dont really notice a scrum until it collapses.

Every time you disagree with a referees decision you are simply restating the relativistic assertion that different observers cannot agree with each others account of events. Therefore the answer to Was the kicker tackled late? depends entirely upon your frame of reference.

The most pre-eminent scientists are each year awarded the Nobel prize by the King of Sweden. Why do we not have something similar in rugby league?

Although I have never been able to bring myself to watch it, Im told that annually the game holds an elaborate ceremony to hand out the Messenger Medals for the best player in each position.

But why arent we rewarding the games greatest thinkers. During the after match grand final presentations each year Id like the former player who has made the greatest intellectual contribution to the game be awarded the Gould Prize by King Wally Lewis.

The leading thinkers in each field have always been eccentric characters. Einstein, Feynman and Yukawa are giants in Modern Physics, just as Elias, Stuart and Sailor are in rugby league.

These men are strange misfits, uncomfortable in regular society. They spend much of their time mumbling to themselves, deeply thinking their beautiful thoughts.

I recently heard a former NSW champion on the radio explain that he was 9.9 percent sure something would happen. This caused some confusion until he explained that he always does percentages out of 10. This has caused me to reexamine many of my assumptions about the nature of mathematics.

Just another example that when these great men speak we listen, and the world is a better place for their game-changing insights.

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Faith: the Axis Upon Which the Wheel of Science Turns – aish.com Ponder, Philosophy, Featured – Aish

Posted: at 11:49 pm

Beneath every "fact" lies a series of assumptions that cannot be proven. Like it or not, even science requires a leap of faith.

Bill Nye, the 'Science Guy,' affirms that his "point of view is based on the facts of life" and not on faith-based "suppositions of life."1 For Nye, science is the only reliable, ultimate, unstoppable, and undeniable guide to truth and is faith-free. While scientific knowledge is the power that saves, faith, for the 'Science Guy,' is a weakness that only blinds. Nye believes that science alone can save the world and that faith must step aside to make way for the future. This is because, says Nye, people of faith "just can't handle the truth."2

But is science really faith free? Max Planck, Nobel laureate in physics and pioneer of quantum theory, thinks not. As Planck explains, "Anybody who has been seriously engaged in scientific work of any kind realizes that over the entrance to the gates of the temple of science are written the words: 'Ye must have faith.' It is a quality which the scientist cannot dispense with."3 For Planck, faith is the axis upon which the wheel of science turns. If one does not have faith, then one may not have science.

To illustrate Planck's insight, consider Nye's claim, "science is the only basis for truth." Is this idea, in and of itself, a truly scientific claim? Not at all. This claim is not open to experimental testing or to falsification. It is a claim that goes beyond the scientific method. There would thus be no purely scientific reason for accepting the truth of the above claim. Consequently, the claim that "science is the only basis for truth" would logically have to be false if it were true. In philosophy, this is what is called a self-defeating claim. At best, the proposition would be a paradox or a mystery, but otherwise, it is just self-referentially incoherent.

The 'Science Guy' Bill Nye is keen on trumpeting the "undeniable facts of science" as opposed to the "mere suppositions" of faith. But can science ever know anything for certain? Consider the confidently asserted certainty of "the central dogma of molecular biology," proclaimed by co-discoverer of the DNA double helix Francis Crick as a "fundamental biological law" in 1956. The central dogma holds that genetic information flows in only one directionfrom DNA (and RNA) to proteins, and never the other way around. This idea was believed to be a biological "law of nature" that operated without exception and was the conceptual basis for the Human Genome Project of the 1990s.

In the early 2000s, however, scientists increasingly witnessed phenomena that broke the biological law. They discovered that DNA can be edited as a result of life experience and that the way DNA is read depends on the surrounding environment. In other words, "the body keeps the score."4 With the discovery of what is today known as epigenetics, it became clear that information can be "transferred from a protein sequence back to the genome." Consequently, explains molecular biologist Eugene Koonin, "the Central Dogma of molecular biology is invalid as an 'absolute' principle: transfer of information from proteins (and specifically from protein sequences) to the genome does exist."5 The history of science is full of such cases where scientists have found exceptions to what were once viewed as exceptionless laws of Nature. How, then, can any scientific facts be undeniable?

Uncertainty in science may be the only scientific fact that we can ever be certain of. This is because science itself has discovered numerous areas where there are limits to what can be known through observation and experiment. Consider, for example, big bang cosmologythe leading scientific theory that describes the universe's origin, structure, and development. According to the standard big bang model, derived from Einstein's theory of general relativity and observational data, the universe began 13.7 billion years ago in a singularityan infinitely small point in which matter was infinitely compressed. Everything that physically exists, including matter, energy, space, and time, came into existence at the big bang singularity. Thus it makes no sense to speak of physical reality or even a "time before" this point.

Science itself has discovered numerous areas where there are limits to what can be known through observation and experiment.

The existence of an initial singularity of this sort represents a fundamental limit to the observational powers of science. Any "science" that speaks of the conditions that gave rise to the singularitysuch as an infinite multiverse or a quantum vacuum stateis not truly scientific because science can never test it. To assert that science will someday be able to adequately describe the conditions "before" or "beyond" the initial singularity is not a statement grounded in current science but, rather, in a philosophical faith.

While big bang cosmology reveals that there are limits to what scientists can know when studying the largest known phenomenon (the whole universe), quantum physics has also shown that there are limits to what scientists can know when studying the smallest conceivable objects (atoms and their constituent parts). Classical physics, which was the standard view of physics before 1900, said that it was possible simultaneously to know both the position and motion of a given particle with complete accuracy. While the precision of a classical physicist might, in practice, be limited only by the available technology, there was no reason in principle to expect that better technology would not eventually overcome such limits.

Quantum physics has also shown that there are limits to what scientists can know when studying the smallest conceivable objects (atoms and their constituent parts).

According to the standard view of current quantum physics, however, even perfect instruments cannot measure the location and velocity of a body simultaneously with impeccable precision. This fundamental limit on the accuracy of measurement is known as Heisenberg's uncertainty principle. As mathematical physicist John Barrow explains, "The quantum picture of reality introduces a new form of impossibility into our picture of the world. This impossibility replaces a past belief in unrestricted experimental investigation of Nature which was based upon a misconception of what existed to be measured."6 With quantum physics, says philosopher of science Michael Ruse, "we seem to have reached an outer point of what we can know."7

The renowned philosopher of science Karl Popper showed that the most exalted status that any scientific theory can reach is "not yet falsified, despite our best efforts."8 Scientific theories can never be verified, proven, or confirmed because an infinite number of experiments remain to be performed before all other possibilities can be ruled out. Consequently, scientific theories can only be falsified. For instance, it takes only one black swan to falsify the hypothesis that all swans are white. If a given hypothesis is to be counted as genuinely scientific, it must make testable predictions about the world that may be potentially refuted by later experimentation or possible observation.

The cornerstone of the scientific mind is its continuous openness to the possibility of being completely wrong. In order for science to function as science and make any progress in knowledge, science must always have humility as its foundation. If a given phenomenon appears to contradict our best-known science, then science must reserve judgment until scientists can find a way to investigate it adequately. Science, in principle, cannot make infallible pronouncements about what is possible. Indeed, our best theory of atomic physics (quantum mechanics) says that scientific accuracy can only deal in probabilities. Science, in both principle and practice, can never know anything for certain. Thus, while Bill Nye's "facts of life" may exist in theory, our most advanced current scientific knowledge of them is middling at bestand always will be.

Featured Image: Unsplash.com, Kinson Leung

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Faith: the Axis Upon Which the Wheel of Science Turns - aish.com Ponder, Philosophy, Featured - Aish

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James Bardeen, an Expert on Unraveling Einsteins Equations, Dies at 83 – The New York Times

Posted: at 11:49 pm

James Bardeen, who helped elucidate the properties and behavior of black holes, setting the stage for what has been called the golden age of black hole astrophysics, died on June 20 in Seattle. He was 83.

His son William said the cause was cancer. Dr. Bardeen, an emeritus professor of physics at the University of Washington, had been living in a retirement home in Seattle.

Dr. Bardeen was a scion of a renowned family of physicists. His father, John, twice won the Nobel Prize in Physics, for the invention of the transistor and the theory of superconductivity; his brother, William, is an expert on quantum theory at the Fermi National Accelerator Laboratory in Illinois.

Dr. Bardeen was an expert on unraveling the equations of Einsteins theory of general relativity. That theory ascribes what we call gravity to the bending of spacetime by matter and energy. Its most mysterious and disturbing consequence was the possibility of black holes, places so dense that they became bottomless one-way exit ramps out of the universe, swallowing even light and time.

Dr. Bardeen would find his lifes work investigating those mysteries, as well as related mysteries about the evolution of the universe.

Jim was part of the generation where the best and brightest went to work on general relativity, said Michael Turner, a cosmologist and emeritus professor at the University of Chicago, who described Dr. Bardeen as a gentle giant.

James Maxwell Bardeen was born in Minneapolis on May 9, 1939. His mother, Jane Maxwell Bardeen, was a zoologist and a high school teacher. Following his fathers work, the family moved to Washington, D.C.; to Summit, N.J.; and then to Champaign-Urbana, Ill., where he graduated from the University of Illinois Laboratory High School.

He attended Harvard and graduated with a physics degree in 1960, despite his fathers advice that biology was the wave of the future. Everybody knew who my father was, he said in an oral history interview recorded in 2020 by the Federal University of Paraguay, adding that he had not felt the need to compete with him. It was impossible, anyway, he said.

Working under the physicist Richard Feynman and the astrophysicist William A. Fowler (who would both become Nobel laureates), Dr. Bardeen obtained his Ph.D. from the California Institute of Technology in 1965. His thesis was about the structure of supermassive stars millions of times the mass of the sun; astronomers were beginning to suspect that they were the source of the prodigious energies of the quasars being discovered in the nuclei of distant galaxies.

After holding postdoctoral positions at Caltech and the University of California, Berkeley, he joined the astronomy department at the University of Washington in 1967. An avid hiker and mountain climber, he was drawn to the school by its easy access to the outdoors.

By then, what the Nobel laureate Kip Thorne, a professor at the California Institute of Technology, refers to as the golden age of black hole research was well underway, and Dr. Bardeen was swept up in international meetings. At one, in Paris in 1967, he met Nancy Thomas, a junior high school teacher in Connecticut who was trying to brush up on her French. They were married in 1968.

In addition to his son William, a senior vice president and the chief strategy officer of The New York Times Company, and his brother, William, Dr. Bardeens wife survives him, along with another son, David, and two grandchildren. A sister, Elizabeth Greytak, died in 2000.

Dr. Bardeen was a member of the National Academy of Sciences, as is his brother and as was his father.

Although he was speedy at math, Dr. Bardeen didnt write any faster than he spoke. William Press, a former student of Dr. Thornes now at the University of Texas, recalled being sent to Seattle to finish a paper that Dr. Bardeen and he were supposed to be writing. Nothing had been written. Dr. Bardeens wife then commanded the two to sit on opposite ends of a couch with a pad of paper. Dr. Bardeen would write a sentence and pass the pad to Dr. Press, who would either reject or approve it and then pass the pad back. Each sentence, Dr. Press said, took a few minutes. It took them three days, but the paper got written.

One of the epochal moments of those years was a monthlong summer school in Les Houches, France, in 1972 featuring all the leading black hole scholars. Dr. Bardeen was one of a half-dozen invited speakers. It was during that meeting that he, Stephen Hawking of Cambridge University and Brandon Carter, now of the Paris Observatory, wrote a landmark paper entitled The Four Laws of Black Hole Mechanics, which became a springboard for future work, including Dr. Hawkings surprise calculation that black holes could leak and eventually explode.

In another famous calculation the same year, Dr. Bardeen deduced the shape and size of a black holes shadow as seen against a field of distant stars a doughnut of light surrounding dark space.

That shape was made famous, Dr. Thorne said, by the Event Horizon Telescopes observations of black holes in the galaxy M87 and in the center of the Milky Way, and by visualizations in the movie Interstellar.

Another of Dr. Bardeens passions was cosmology. In a 1982 paper, he, Dr. Turner and Paul Steinhardt of Princeton described how submicroscopic fluctuations in the density of matter and energy in the early universe would grow and give rise to the pattern of galaxies we see in the sky today.

Jim was delighted that we used his formalism, Dr. Turner said, and was sure we got it right.

Dr. Bardeen moved to Yale in 1972. Four years later, unhappy with the academic bureaucracy in the East and yearning for the outdoors again, he moved back to the University of Washington. He retired in 2006.

But he never stopped working. Dr. Thorne recounted a recent telephone conversation in which they reminisced about the hiking and camping trips they used to take with their families. In the same conversation, Dr. Bardeen described recent ideas he had about what happens as a black hole evaporates, suggesting that it might change into a white hole.

That was one aspect of Jim in a nutshell, Dr. Thorne wrote in an email, thinking deeply about physics in creative new ways right up to the end of his life.

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Mjlnir: The physics that could stop the unworthy from wielding Thor’s hammer – BBC Science Focus Magazine

Posted: at 11:49 pm

According to comic book legend, the hammer of Thor, Mjlnir, can only be lifted by those who are deemed worthy enough to wield it. Now, with Thor: Love And Thunder due for release, this has inevitably led to questions.

What makes someone worthy? How does the hammer stop the likes of the Hulk from lifting it? And if even the Hulk cannot lift it, how much must it weigh? Its a debate so enduring that it made its way into 2015s Avengers: Age Of Ultron, where all of the Avengers took turns trying (and failing) to lift the hammer off a table. The handles imprinted, right? suggests an annoyed Tony Stark. Like a security code?

James Kakalios, a physics professor at the University of Minnesota, and author of The Physics Of Superheroes, has spent more time than most thinking about Thors hammer. So much so, in fact, that his theory for how it works was cited by Bruce Banner himself in an issue of the 2012 comic The Indestructible Hulk. For a start, Kakalios suggests that Stark wasnt that far off with his idea of the hammers handle featuring a fingerprint scanner.

The science of the Asgardians is so advanced that to us it would seem like magic, he says. It makes sense that Mjlnir would possess a form of artificial intelligence that, when you grab the handle, uses some sort of biosensor to scan whether youre worthy. He uses a scene from the first Thor movie to illustrate his point. Odin banishes Thor, after whispering to Mjlnir, whoever holds this hammer, if they be worthy, shall possess the power of Thor. So basically Odin has administrator rights to rewrite the hammers operating code.

But even if that was true, how does Mjlnir also repel the unworthy by making itself impossible to lift? Kakalioss Bruce-Banner-approved theory pivots around gravitons. These are fundamental particles that have not yet been confirmed to exist on Earth, but could exist in the scientifically advanced society of Asgard.

No one has observed a graviton yet, he says, but it is believed to be the quantum mediator of the gravitational force; much like photons of light are the quantum excitation of the electromagnetic field.

Natalie Portman and Chris Hemsworth in Thor: Love and Thunder Disney/Marvel

Kakalioss theory is that when Mjlnir is grabbed by someone it has deemed unworthy, it emits gravitons to make the hammer a heavier weight than the individual can lift. This, Kakalios says, explains why the hammer does not fall through the table in Avengers: Age Of Ultron because it is able to use gravitons to adjust its weight and nullify whatever force is being exerted on it.

It will only emit those excess gravitons while youre trying to lift it, says Kakalios. Lets say the hammer weighs 40 pounds. It exerts a force of 40 pounds on the table and the table pushes back with a weight of 40 pounds. So the hammer doesnt move. You then try to lift it off the table with a force of 80 pounds. You should be able to because 80 up is greater than 40 down.

"But if the hammer at that moment knows how much force youre exerting, it could emit gravitons so now it weighs 80 pounds. Your 80 and its 80 balance out. The moment you let go, it stops emitting the gravitons and goes back to weighing 40 pounds, meaning it can sit on the table just fine.

Or, of course, it could just be magic.

Verdict: Mjlnirs traits might be weird, but it can all be explained by Asgardian physics... even if their physics is different from ours.

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Sunday Social: Debut try, a kick to win and heartwarming gestures – Yahoo Eurosport UK

Posted: at 11:49 pm

Credit: PA Images

It is time for Planet Rugbys Sunday Social, your quirky recap of the serious and not so serious talking points from the past weeks action.

Kicking off with an outrageous debut try from Henry Arundell! Everything this youngster touches seems to turn to gold. It looks like England has another Test superstar loading. Brilliant stuff from the London Irish speedster!

The leg drive has to come from somewhere! A humorous take on the source of Arundells power. Scandalously exciting debut indeed.

Wow! An aggressive push to the head from Jonny Hill on Wallaby Darcy Swain. How on earth has this gone unnoticed by the match officials? It truly was a robust clash between the two old rivals.

The heat between the two continued until Swain got himself a red card for a headbutt. It is never nice to see these kinds of scuffles on the pitch. Unnecessary and ill-disciplined. Poor from both parties here.

As soon as Englands Maro Itoje started screaming at the Australian line-out, the meme creators of the internets underbelly kicked into overdrive! A good laugh from Squidge Rugby, who has his take on a strange moment.

Another one! Sorry, Itoje, but there was no other outcome. The image sums up Englands second half. Springboks supporters probably felt the same about their first half at Loftus Versfeld against Wales.

ICE in his veins. Springbok Damian Willemse steps up after the hooter and nails the penalty to win. That is incredible composure for a player that has not kicked much at goal all seasonpure class.

If anyone has forgotten how ridiculously talented All Black Ardie Savea is, here is your reminder. What a game by the number eight scoring a brace! World-class performer.

What a heartwarming moment! A lovely lady hands the Wallabies captain Michael Hooper a chocolate bar for his efforts on the field. A kind and warm gesture.

Brothers in arms! Always lovely to see two siblings representing their country together. Paolo and Alessandro Garbisi lining up for Italy! What a moment that is for the Garbisi family.

Story continues

The Champions Cup draw was completed this week, but you will need a Quantum Physics degree to make sense of what is going on. Surely there must be a more simple method? Is this the best they can do?

Remembering an iconic moment for the Lions. Who does not like seeing Israel Folau carried like a naughty child by George North? Immense power is showcased in a bizarre moment in rugby.

Leicester Tigers assistant coach Kevin Sinfield took an old friend and teammate Rob Burrow, who suffers from Motor Neurone Disease, on a 10-kilometre run to raise money for the cause. Fantastic stuff from the pair who have already raised a great deal of money. Rugby is more than just a game. The camaraderie and brotherhood transcend the sport.

READ MORE:Eddie Jones: Darcy Swain red-card influenced refereeing decisions to even the game up

The article Sunday Social: Debut try, a kick to win and heartwarming gestures appeared first on Planetrugby.com.

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Cosmic phenomenon predicted by Einstein could shatter physics as we know it – Inverse

Posted: at 11:49 pm

On February 11, 2016, researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced the detection of gravitational waves for the first time. As predicted by Einsteins General Theory of Relativity, these waves result from massive objects merging, which causes ripples through spacetime that can be detected.

Since then, astrophysicists have theorized countless ways that gravitational waves could be used to study physics beyond the standard models of gravity and particle physics and advance our understanding of the Universe.

To date, gravitational waves have been proposed as a means of studying dark matter, the interiors of neutron stars and supernovae, mergers between supermassive black holes, and more.

Whats new In a recent study, a team of physicists from the University of Amsterdam and Harvard University has proposed a way where gravitational waves could be used to search for ultralight bosons around rotating black holes. This method could not only offer a new way to discern the properties of binary black holes but could lead to the discovery of new particles beyond the Standard Model.

The research was conducted by researchers at the Gravitation Astroparticle Physics Amsterdam (GRAPPA), at the University of Amsterdam, with support provided by the Center for Theoretical Physics and the National Center for Theoretical Sciences at the University of Taipei (Taiwan), and Harvard University. The paper that describes their work, titled Sharp Signals of Boson Clouds in Black Hole Binary Inspirals, recently appeared in the Physical Review Letters.

Its a well-known fact that normal matter will infall toward black holes over time, which will form an accretion disk around its outer edge (aka. Event Horizon). This disk will be accelerated to incredible speeds, causing the material within to become super-heated and release tremendous amounts of radiation while slowly being accreted onto the black holes face. However, for the past few decades, scientists have observed that black holes will shed some of their mass through a process called superradiance.

This phenomenon was studied by Stephen Hawking, who described how rotating black holes would throw off radiation that would appear real to a nearby observer, but virtual to a distant one. In the process of transferring this radiation from one reference frame to another, the acceleration of the particle itself would cause it to transform from virtual to real. This exotic form of energy, known as Hawking Radiation, will form clouds of low-mass particles around a black hole. This leads to a gravitational atom, so-named because they resemble ordinary atoms (clouds of particles surrounding a core)

While scientists know that this phenomenon occurs, they also understand that it could only be explained through the existence of a new ultralight particle that exists beyond the Standard Model. This was the focus of the new paper, where lead author Daniel Baumann (GRAPPA and the University of Taipei) and his colleagues examined how superradiance causes unstable clouds of ultralight bosons to form around black holes spontaneously. In addition, they suggest that the similarities between gravitational and regular atoms go deeper than their structure.

In short, they suggest that binary black holes could cause particles in their clouds to become ionized via the photoelectric effect. As described by Einstein, this occurs when electromagnetic energy (such as light) makes contact with a material, causing it to emit excited electrons (photoelectrons). When applied to a binary black hole, Baumann and his colleagues show how clouds of ultralight bosons could absorb the orbital energy of a black hole companion. This would cause some of the bosons to become ejected and accelerated, evident from the black holes associated gravitational wave signals.

Lastly, they demonstrated how this process could dramatically alter the evolution of binary black holes by reducing the time it takes for the objects to merge. As they state:

These kinks, they argue, will be discernible to next-generation gravitational wave interferometers like the Laser Interferometer Space Antenna (LISA). This process could be used to discover an entirely new class of ultralight particles and provide direct information about the mass and state of gravitational atom clouds. In short, the ongoing studies of gravitational waves using more sensitive interferometers could reveal exotic physics that advance our understanding of black holes and lead to new breakthroughs in particle physics.

This is one of many possibilities that have been ventured thanks to the revolution taking place with gravitational wave astronomy. In the coming years, astrophysicists hope to use them to probe the most extreme environments in the Universe, like black holes and neutron stars. They also hope that primordial gravitational waves will reveal things about the early Universe, help resolve the mystery of the matter/anti-matter imbalance, and lead to a quantum theory of gravity (aka. a Theory of Everything).

This article was originally published on Universe Today by Matt Williams. Read the original article here.

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Fireworks are only possible because of quantum physics – Big Think

Posted: June 30, 2022 at 9:29 pm

This Monday, July 4, 2022, is remarkable for a number of reasons. It happens to be aphelion: the day where the Earth is at its most distant from the Sun as it revolves through the Solar System in its elliptical orbit. Its the 246th anniversary of when the United States officially declared independence from, and war on, Britain. And it marks the annual date where the wealthiest nation in the world sets off more explosivesin the form of fireworksthan any other.

Whether youre an amateur hobbyist, a professional installer, or simply a spectator, fireworks showsare driven by the same laws of physicsthat govern all of nature. Individual fireworks all contain the same four component stages: launch, fuse, burst charges, and stars. Without quantum physics, not a single one of them would be possible. Heres the science behind how every component of these spectacular shows works.

The anatomy of a firework consists of a large variety of elements and stages. However, the same four basic elements are the same across all types and styles of fireworks: the lift charge, the main fuse, a burst charge, and stars. Variations in the diameter of the launch tube, the length of the time-delay fuse, and the height of the fireworks are all necessary to ignite the stars with the proper conditions during the break.

The start of any firework is the launch aspect: the initial explosion that causes the lift. Ever sincefireworks were first inventedmore than a millennium ago, the same three simple ingredients have been at the heart of them: sulfur, charcoal, and a source of potassium nitrate. Sulfur is a yellow solid that occurs naturally in volcanically active locations, while potassium nitrate is abundant in natural sources like bird droppings or bat guano.

Charcoal, on the other hand, isnt the briquettes we commonly use for grilling, but the carbon residue left over from charring (or pyrolyzing) organic matter, such as wood. Once all the water has been removed from the charcoal, all three ingredients can be mixed together with a mortar and pestle. The fine, black powder that emerges is gunpowder, already oxygen-rich from the potassium nitrate.

The three main ingredients in black powder (gunpowder) are charcoal (activated carbon, at left), sulfur (bottom right) and potassium nitrate (top right). The nitrate portion of the potassium nitrate contains its own oxygen, which means that fireworks can be successfully launched and ignited even in the absence of external oxygen; they would work just as well on the Moon as they do on Earth.

With all those ingredients mixed together, theres a lot of stored energy in the molecular bonds holding the different components together. But theres a more stable configuration that these atoms and molecules could be rearranged into. The raw ingredientspotassium nitrate, carbon, and sulfurwill combust (in the presence of high-enough temperatures) to form solids such as potassium carbonate, potassium sulfate, and potassium sulfide, along gases such as carbon dioxide, nitrogen, and carbon monoxide.

All it takes to reach these high temperatures is a small heat source, like a match. The reaction is a quick-burning deflagration, rather than an explosion, which is incredibly useful in a propulsion device. The rearrangement of these atoms (and the fact that the fuel contains its own oxygen) allows the nuclei and electrons to rearrange their configuration, releasing energy and sustaining the reaction. Without the quantum physics of these rearranged bonds, there would be no way to release this stored energy.

The Macys Fourth of July fireworks celebration that takes place annually in New York City displays some of the largest and highest fireworks you can find in the United States of America and the world. This iconic celebration, along with all the associated lights and colors, is only possible because of the inescapable rules of quantum mechanics.

When that first energy release occurs, conventionally known as the lift charge, it has two important effects.

The upward acceleration needs to give your firework the right upward velocity to get it to a safe height for explosion, and the fuse needs to be timed appropriately to detonate at the peak launch height. A small fireworks show might have shells as small as 2 inches (5 cm) in diameter, which require a height of 200 feet (60 m), while the largest shows (like the one by the Statue of Liberty in New York) have shells as large as 3 feet (90 cm) in diameter, requiring altitudes exceeding 1000 feet (300 m).

Different diameter shells can produce different sized bursts, which require being launched to progressively higher altitudes for safety and visibility reasons. In general, larger fireworks must be launched to higher altitudes, and therefore require larger lift charges and longer fuse times to get there. The largest fireworks shells exceed even the most grandiose of the illustrations in this diagram.

The fuse, on the other hand, is the second stage and will be lit by the ignition stage of the launch.Most fusesrely on a similar black powder reaction to the one used in a lift charge, except the burning black powder core is surrounded by wrapped textile coated with either wax or lacquer. The inner core functions via the same quantum rearrangement of atoms and electron bonds as any black powder reaction, but the remaining fuse components serve a different purpose: to delay ignition.

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The textile material is typically made of multiple woven and coated strings. The coatings make the device water resistant, so they can work regardless of weather. The woven strings control the rate of burning, dependent on what theyre made out of, the number and diameter of each woven string, and the diameter of the powder core. Slow-burning fuses might take 30 seconds to burn a single foot, while fast-burning fuses can burn hundreds of feet in a single second.

The three main configurations of fireworks, with lift charges, fuses, burst charges and stars all visible. In all cases, a lift charge launches the firework upward from within a tube, igniting the fuse, which then burns until it ignites the burst charge, which heats and distributes the stars over a large volume of space.

The third stage, then, is the burst charge stage, which controls the size and spatial distribution of the stars inside. In general the higher you launch your fireworks and the larger-diameter your shells are, the larger your burst charge will need to be to propel the insides of the shell outward. In general, the interior of the firework will have a fuse connected to the burst charge, which is surrounded by the color-producing stars.

Theburst chargecan be as simple as another collection of black powder, such as gunpowder. But it could be far more complex, such as the much louder and more impressiveflash powder, or a multi-stage explosive that sends stars in multiple directions. By utilizing different chemical compounds that offer different quantum rearrangements of their bonds, you can tune your energy release, the size of the burst, and the distribution and ignition times of the stars.

Differently shaped patterns and flight paths are highly dependent on the configuration and compositions of the stars inside the fireworks themselves. This final stage is what produces the light and color of fireworks, and is where the most important quantum physics comes into play.

But the most interesting part is that final stage: where the stars ignite. The burst is what takes the interior temperatures to sufficient levelsto create the light and colorthat we associate with these spectacular shows. The coarse explanation is that you can take different chemical compounds, place them inside the stars, and when they reach a sufficient temperature, they emit light of different colors.

This explanation, though, glosses over the most important component: the mechanism of how these colors are emitted. When you apply enough energy to an atom or molecule, you can excite or even ionize the electrons that conventionally keep it electrically neutral. When those excited electrons then naturally cascade downward in the atom, molecule or ion, they emit photons, producing emission lines of a characteristic frequency. If they fall in the visible portion of the spectrum, the human eye is even capable of seeing them.

Whether in an atom, molecule, or ion, the transitions of electrons from a higher energy level to a lower energy level will result in the emission of radiation at a very particular wavelength. This produces the phenomenon we see as emission lines, and is responsible for the variety of colors we see in a fireworks display.

What determines which emission lines an element or compound possesses? Its simply the quantum mechanics of the spacing between the different energy levels inherent to the substance itself. For example, heated sodium emits a characteristic yellow glow, as it has two very narrow emission lines at 588 and 589 nanometers. Youre likely familiar with these if you live in a city, as most of those yellow-colored street lamps you see are powered by elemental sodium.

As applied to fireworks, there are a great variety of elements and compounds that can be utilized to emit a wide variety of colors. Different compounds of Barium, Sodium, Copper and Strontium can produce colors covering a huge range of the visible spectrum, and the different compounds inserted in the fireworks stars are responsible for everything we see. In fact,the full spectrum of colors can be achievedwith just a handful of conventional compounds.

The interior of this curve shows the relationship between color, wavelength, and temperature in chromaticity space. Along the edges, where the colors are most saturated, a variety of elements, ions, and compounds can be shown, with their various emission lines marked out. Note that many elements/compounds have multiple emission lines associated with them, and all of these are used in various fireworks. Because of how easy it is to create barium oxide in a combustion reaction, certain firework colors, such as forest green and ocean green, remain elusive.

Whats perhaps the most impressive about all of this is that the color we see with the human eye is not necessarily the same as the color emitted by the fireworks themselves. For example, if you were to analyze the light emitted by a violet laser, youd find that the photons emerging from it were of a specific wavelength that corresponded to the violet part of the spectrum.

The quantum transitions that power a laser always result in photons of exactly the same wavelength, and our eyes see them precisely as they are, with the multiple types of cones we possess responding to that signal in such a way that our brain responds to construct a signal thats commensurate with the light possessing a violet color.

A set of Q-line laser pointers showcase the diverse colors and compact size that now are commonplace for lasers. By pumping electrons into an excited state and stimulating them with a photon of the desired wavelength, you can cause the emission of another photon of exactly the same energy and wavelength. This action is how the light for a laser is first created: by the stimulated emission of radiation.

But if you look at that same color that appears as violet not from a monochromatic source like a laser, but from your phone or computer screen, youll find that there are no intrinsically violet photons striking your eyes at all! Instead,as Chad Orzel has noted in the past,

Our eyes construct what we perceive as color from the response of three types of cells in our retina, each sensitive to light of a particular range of colors. One is most sensitive to blue-ish light (short wavelength), one is most sensitive to red light (long wavelength), and the third to a sort of yellow-green. Based on how strongly each of these cells responds to incoming light, our brains construct our perception ofcolor.

In other words, the key to producing the fireworks display you want isnt necessarily to create light of a specific color that corresponds to a specific wavelength, but rather to create light that excites the right molecules in our body to cause our brain to perceive a particular color.

A violet laser emits photons of a very particular, narrow wavelength, as every photon carries the same amount of energy. This curve, shown in blue, emits violet photons only. The green curve shows how a computer screen approximates the same exact violet color by using a mix of different wavelengths of light. Both appear to be the same color to human eyes, but only one truly produces photons of the same color that our eyes perceive.

Fireworks might appear to be relatively simple explosive devices. Pack a charge into the bottom of a tube to lift the fireworks to the desired height, ignite a fuse of the proper length to reach the burst charge at the peak of its trajectory, explode the burst charge to distribute the stars at a high temperature, and then watch and listen to the show as the sound, light, and color washes over you.

Yet if we look a little deeper, we can understand how quantum physics underlies every single one of these reactions. Add a little bit extrasuch as propulsion or fuel inside each starand your colored lights can spin, rise, or thrust in a random direction. Make sure you enjoy your fourth of July safely, but also armed with the knowledge that empowers you to understand how the most spectacular human-made light show of the year truly works!

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