Posts Tagged ‘Physics’
Science has a habit of asking stupid questions. Stupid, that is, by the standards of common sense. But time and time again we have found that common sense is a poor guide to what really goes on in the world.
So if your response to the question “Why does time always go forwards, not backwards?” is that this is a daft thing to ask, just be patient…
In our experience the past is the past and the future is the future, but sometimes the two can cross over; and while the past seems set in stone, some scientists believe that the future can change it: “The quantum origin of time.”
* William Faulkner,
As we head down the rabbit hole, we might spare a thought for Jules Henri Poincaré; he died on this date in 1912. A mathematician, theoretical physicist, engineer, and a philosopher of science, Poincaré is considered the “last Universalist” in math– the last mathematician to excel in all fields of the discipline as it existed during his lifetime.
Poincaré was a co-discoverer (with Einstein and Lorentz) of the special theory of relativity; he laid the foundations for the fields of topology and chaos theory; and he had a huge impact on cosmogony. His famous “Conjecture” held that if any loop in a given three-dimensional space can be shrunk to a point, the space is equivalent to a sphere; it remained unsolved until Grigori Perelman completed a proof in 2003.
“I used to think information was destroyed in black holes. This was my biggest blunder, or at least my biggest blunder in science”*…
Gravitational waves sent out from a pair of colliding black holes have been converted to sound waves, as heard in this animation. On September 14, 2015, LIGO [the Laser Interferometer Gravitational-wave Observatory] observed gravitational waves from the merger of two black holes, each about 30 times the mass of our sun. The incredibly powerful event, which released 50 times more energy than all the stars in the observable universe, lasted only fractions of a second.
In the first two runs of the animation, the sound-wave frequencies exactly match the frequencies of the gravitational waves. The second two runs of the animation play the sounds again at higher frequencies that better fit the human hearing range. The animation ends by playing the original frequencies again twice.
As the black holes spiral closer and closer in together, the frequency of the gravitational waves increases. Scientists call these sounds “chirps,” because some events that generate gravitation waves would sound like a bird’s chirp.
More background from LIGO:
* Stephen Hawking
As we scan the event horizon, we might send difficult-to-detect birthday greetings to Lawrence Maxwell Krauss; he was born on this date in 1954. A theoretical physicist and cosmologist, Dr. Krauss was among the first to propose the existence of the enigmatic dark energy that makes up most of the mass and energy in the universe. He directs the Origins Project, and has written several books on science for the general public, including Fear of Physics (1993), The Physics of Star Trek (1995), Quantum Man: Richard Feynman’s Life in Science (2011), and A Universe from Nothing (2012).
… imposing old Newtonian Schema thinking on new quantum-scale phenomena has landed us in situations with no good explanations whatsoever. If these phenomena seem inexplicable, we may just be thinking about them in the wrong way. Much better explanations become available if we are willing to take the future into account as well as the past. But Newtonian-style thinking is inherently incapable of such time-neutral explanations. Computer programs run in only one direction, and trying to combine two programs running in opposite directions leads to the paradoxical morass of poorly plotted time-travel movies. In order to treat the future as seriously as we treat the past, we clearly need an alternative to the Newtonian Schema.
And we have one. Most physicists are well aware of a different framework, an alternative where space and time are analyzed in an even-handed manner. This so-called Lagrangian Schema also has old roots and has become an essential tool in every field of fundamental physics. But even physicists who regularly use this approach have resisted the last obvious step: thinking of the Lagrangian Schema not just as a mathematical trick, but as a way to explain the world. Perhaps we haven’t been taking our own theories seriously enough.
The Lagrangian Schema doesn’t just allow future-based explanations. It demands them. By treating the future and the past on the same footing, this framework avoids paradoxes and makes new explanatory opportunities available. And it just might be the viewpoint that physics needs for the next major breakthrough…
More at “To Understand Your Past, Look to Your Future.”
As we disentangle entanglement, we might spare a thought for Bede (or as he is more frequently remembered, Venerable Bede); he died on this date in 735. An English monk, Bede studied and wrote widely on scientific, historical, and theological topics, ranging from music and metrics to exegetical Scripture commentaries. He was an accomplished translator (Pliny the Elder, Virgil, Lucretius, Ovid, Horace, and other classical writers in both Greek and Hebrew). And his Historia ecclesiastica gentis Anglorum (The Ecclesiastical History of the English People) has earned him the title “The Father of English History.” Indeed, it was in this work that Bede established as common practice the use of “BC” and “AD” with dates.
Just when the confirmation of gravity waves seemed conclusively to affirm Einstein’s theory of general relativity…
If you thought regular black holes were about as weird and mysterious as space gets, think again, because for the first time, physicists have successfully simulated what would happen to black holes in a five-dimensional world, and the way they behave could threaten our fundamental understanding of how the Universe works.
The simulation has suggested that if our Universe is made up of five or more dimensions – something that scientists have struggled to confirm or disprove – Einstein’s general theory of relativity, the foundation of modern physics, would be wrong. In other words, five-dimensional black holes would contain gravity so intense, the laws of physics as we know them would fall apart…
“If naked singularities exist, general relativity breaks down,” said one of the team, Saran Tunyasuvunakool. “And if general relativity breaks down, it would throw everything upside down, because it would no longer have any predictive power – it could no longer be considered as a standalone theory to explain the Universe.”
If our Universe only has four dimensions, everything is cool, and ring-shaped black holes and naked singularity are not a thing. But physicists have proposed that our Universe could be made up of as many as 11 dimensions. The problem is that because humans can only perceive three, the only way we can possibly confirm the existence of more dimensions is through high-energy experiments such as the Large Hadron Collider…
* Robert Coover, A Child Again
As we marvel at models, we might send very carefully-crafted birthday greetings to Jacques de Vaucanson; he was born on this date in 1709. A mechanical genius, de Vaucanson invented a number of machine tools still in use (e.g., the slide rest lathe) and created the first automated loom (the inspiration for Jacquard). But he is better remembered as the creator of extraordinary automata. Among his most famous creations: The Flute Player (with hands gloved in skin) and The Tambourine Player, life-sized mechanical figures that played their instruments impressively. But his masterpiece was The Digesting Duck; remarkably complex (it had 400 moving parts in each wing alone), it could flap its wings, drink water, eat grain– and defecate.
Sans…le canard de Vaucanson vous n’auriez rien qui fit ressouvenir de la gloire de la France. (Without…the duck of Vaucanson, you will have nothing to remind you of the glory of France)
Scientific papers, at the very dawn of that writing form, hadn’t yet evolved the conventions we’re so familiar with today. As a result, the contents of that first volume (and those that followed) are a fascinating mix of the groundbreaking, the banal, and the bizarre. Some are written as letters, some take the form of essays, some are abstracts or reviews of separately published books, and some are just plain inscrutable…
For example, this contribution from Robert Boyle, the father of modern chemistry and a pioneer of the scientific method:
A New Frigorifick Experiment Shewing, How a Considerable Degree of Cold May be Suddenly Produced without the Help of Snow, Ice, Haile, Wind, or Niter, and That at Any Time of the Year – Robert Boyle (again!) (Phil Trans 1:255-261). The word “frigorific”, which Boyle apparently coined for this title, meant “producing cold”, and Boyle’s claim was that simply mixing ammonium chloride into water would cool the solution down. This doesn’t seem to actually be true (saltpetre is frigorific; straight ammonium chloride can keep water liquid below normal freezing point, but isn’t actually frigorific). But although Boyle’s title is a bit hyperbolic, and he does go on a bit, he describes his experiments quite lucidly, so it’s probably unfair to call this one a weird paper. Whether Boyle was right or wrong, here he was doing modern science…
Stephen Heard observes…
Boyle’s Frigorifick paper raises an important point: not every paper in the early Philosophical Transactions was weird, even if in a few case it takes a close reading to realize that. The oddities are interspersed with important observations (like those of Jupiter’s Great Red Spot) and descriptions of major advances (like Robert Hooke’s microscopic observations of cells). But the oddities are there by the dozen, and they give the impression of a freewheeling, chaotic, and perhaps somewhat credulous period at the birth of modern science. It was not yet quite clear where the boundaries of science were – where to draw the lines between science and engineering, or architecture, or alchemy, or wild speculation…
See more examples and learn more at “The Golden Age of Weird Papers.”
* Albert Einstein
As we scratch our chins, we might spare a thought for Max Born; he died on this date in 1970. A German physicist and Nobel Laureate, he coined the phrase “quantum mechanics” to describe the field in which he made his greatest contributions. But beyond his accomplishments as a practitioner, he was a master teacher whose students included Enrico Fermi and Werner Heisenberg– both of whom became Nobel Laureates before their mentor– and J. Robert Oppenheimer.
Less well-known is that Born, who died in 1970, was the grandfather of Australian phenom and definitive Sandy-portrayer Olivia Newton-John.
“The atoms or elementary particles themselves are not real; they form a world of potentialities or possibilities rather than one of things or facts”*…
There is nothing new to be discovered in physics now. All that remains is more and more precise measurement
– Lord Kelvin, 1900
Kelvin’s (in)famous assertion, among others, have led to the sense that physics at the fin de siècle was believed by scientists at the time to be on the point of completion. But that could not be further from the truth. On the contrary, at that moment almost anything seemed possible. At the end of the 19th century, inspired by radical advances in technology, physicists asserted the reality of invisible worlds — an idea through which they sought to address not only psychic phenomena such as telepathy, but also spiritual questions around the soul and immortality.
* Werner Heisenberg
As we recall that all things are relative, we might send bounteous birthday greetings to Charles Alfred Coulson; he was born on this date in 1910. A mathematician and theoretical chemist, Coulson was a pioneer of the application of the quantum theory of valency to problems of molecular structure, dynamics and reactivity. He was Rouse Ball Professor of Mathematics at the University of Oxford (a position in which he was preceded by E. A. Milne, the mathematician and astrophysicist, and succeeded by Roger Penrose), and was a founder and Director of Oxford’s Mathematical Institute.
It’s bad enough for the first kid when a new baby shows up to steal your thunder. But the injustice is compounded when you have to start wearing glasses while your little sibling stays as cute and non-four-eyed as ever. If this sounds familiar, you’re not alone: firstborn kids are more likely to be nearsighted…
Focus on the facts of the case, and learn the possible reasons, at “Why More Firstborn Kids Need Glasses.”
* Henny Youngman
As we reconcile ourselves to the reality that four eyes are better than none, we might spare a thought for John Tyndall; he died on this date in 1893. A prominent 19th-century physicist, he was known for his work on a range of subjects, from crystals to diamagnetism and infrared radiation. But he is probably best remembered as the man who explained (in his book Light) why the sky is blue. And he was perhaps most impactful in his development of the “light fountain“– which demonstrated the scientific foundation for modern fiber optic technology.