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Posts Tagged ‘relativity

“Time is the longest distance between two places”*…


In quantum mechanics, time is universal and absolute; its steady ticks dictate the evolving entanglements between particles. But in general relativity (Albert Einstein’s theory of gravity), time is relative and dynamical, a dimension that’s inextricably interwoven with directions x, y and z into a four-dimensional “space-time” fabric. The fabric warps under the weight of matter, causing nearby stuff to fall toward it (this is gravity), and slowing the passage of time relative to clocks far away. Or hop in a rocket and use fuel rather than gravity to accelerate through space, and time dilates; you age less than someone who stayed at home.

Unifying quantum mechanics and general relativity requires reconciling their absolute and relative notions of time. Recently, a promising burst of research on quantum gravity has provided an outline of what the reconciliation might look like — as well as insights on the true nature of time…

The effort to unify quantum mechanics and general relativity means reconciling totally different notions of time; catch up on the state of play at “Quantum Gravity’s Time Problem.”

* Tennessee Williams, The Glass Menagerie


As we set our watches, we might send carefully-calculated birthday greetings to Gabrielle-Émilie Le Tonnelier de Breteuil, Marquise du Châtelet, the French mathematician and physicist who is probably (if unfairly) better known as Voltaire’s mistress; she was born on this date in 1706.  Fascinated by the work of Newton and Leibniz, she dressed as a man to frequent the cafes where the scientific discussions of the time were held.  Her major work was a translation of Newton’s Principia, for which Voltaire wrote the preface; it was published a decade after her death, and was for many years the only translation of the Principia into French.

Judge me for my own merits, or lack of them, but do not look upon me as a mere appendage to this great general or that great scholar, this star that shines at the court of France or that famed author. I am in my own right a whole person, responsible to myself alone for all that I am, all that I say, all that I do. it may be that there are metaphysicians and philosophers whose learning is greater than mine, although I have not met them. Yet, they are but frail humans, too, and have their faults; so, when I add the sum total of my graces, I confess I am inferior to no one.
– Mme du Châtelet to Frederick the Great of Prussia


Written by LW

December 17, 2016 at 1:01 am

“Nothing puzzles me more than time and space; and yet nothing troubles me less”…


Time crystals– crystals that break both spacial and temporal symmetry– were first predicted by Nobel laureate Frank Wilczek in 2012… and were widely deemed amusing, but impossible (e.g., here).  Now researchers have created time crystals for the first time and say they could one day be used as quantum memories… and might help reconcile Quantum Mechanics with the Theory of Relativity.

Bend your mind at “Physicists Create World’s First Time Crystal,” also here and here (source of the photo above).

* Charles Lamb


As we ponder Einstein’s insistence that time is an illusion, we might send well-structured birthday greetings to Pierre-Gilles de Gennes; he was born on this date in 1932.  A French physicist, he was awarded the 1991 Nobel Prize for Physics for “discovering that methods developed for studying order phenomena in simple systems can be generalized to more complex forms of matter, in particular to liquid crystals and polymers.”  He described mathematically how, for example, magnetic dipoles, long molecules or molecule chains can under certain conditions form ordered states, and what happens when they pass from an ordered to a disordered state.  Such changes of order occur when, for example, a heated magnet changes from a state in which all the small atomic magnets are lined up in parallel to a disordered state in which the magnets are randomly oriented.  Later, he was concerned with the physical chemistry of adhesion.



Written by LW

October 24, 2016 at 1:01 am

“If it was so, it might be; and if it were so, it would be; but as it isn’t, it ain’t. That’s logic.”*…


Your correspondent is headed into the chilly wilds for the Thanksgiving holiday, so this will be the last post until after the passing of the tryptophan haze.  By way of keeping readers amused in the meantime, the puzzle above…

Find a step-by-step guide to its answer at “How to Solve the Hardest Logic Puzzle Ever.”

* Tweedledee, in Lewis Caroll’s Through the Looking-Glass, and What Alice Found There


As we muddle in the excluded middle, we might recall that it was on this date in 1915 that Albert Einstein presented the Einstein Field Equations to the Prussian Academy of Sciences.  Einstein developed what was elaborated into a set of 10 equations to account for gravitation in the curved spacetime described in his General Theory of Relativity; they are used to determine spacetime geometry.

(German mathematician David Hilbert reached the same conclusion, and actually published the equation before Einstein– though Hilbert, who was a correspondent of Einstein’s, never suggested that Einstein’s credit was inappropriate.)

On the right side of the equal sign, the distribution of matter and energy in space; on the left, the geometry of the space, the so-called metric, a prescription for how to compute the distance between two points.



Written by LW

November 25, 2015 at 1:01 am

Why did 5 eat 6?…


For over two decades, The Simpsons has been one of the best written and most entertaining programs on television.  Simon Singh believes that he’s discovered the series’ secret sauce:  it’s written by math geeks who unreservedly lard the show with math gags…

The first proper episode of the series in 1989 contained numerous mathematical references (including a joke about calculus), while the infamous “Treehouse of Horror VI” episode presents the most intense five minutes of mathematics ever broadcast to a mass audience. Moreover, The Simpsons has even offered viewers an obscure joke about Fermat’s last theorem, the most notorious equation in the history of mathematics.

These examples are just the tip of the iceberg, because the show’s writing team includes several mathematical heavyweights. Al Jean, who worked on the first series and is now executive producer, went to Harvard University to study mathematics at the age of just 16. Others have similarly impressive degrees in maths, a few can even boast PhDs, and Jeff Westbrook resigned from a senior research post at Yale University to write scripts for Homer, Marge and the other residents of Springfield…

More on the numerical nuttiness here.

And readers can test themselves against The Simpsons writing room in this multiple choice test (wherein one will find, among other amusements, the answer to the riddle in the title above).


As we wonder how cartoon characters count with only four fingers, we might pause to remember Sir Arthur Stanley Eddington, OM, FRS; he died in this date in 1944.  An astrophysicist, mathematician, and philosopher of science known for his work on the motion, distribution, evolution and structure of stars, Eddington is probably best remembered for his relationship to Einstein:  he was, via a series of widely-published articles, the primary “explainer” of Einstein’s Theory of General Relativity to the English-speaking world; and he was, in 1919, the leader of the experimental team that used observations of a solar eclipse to confirm the theory.



Written by LW

November 22, 2013 at 1:01 am

Step Right Up!…

The rakishly-named Jen Wayne Gacy maintains what has to be one of the most unusual– and fascinating– Pinterest collections online.  Your correspondent’s personal favorite:  “Slideshow/Freakshow.”

Tour the netherworld at “Slideshow/Freakshow.”  (And learn the lingo here.)

[TotH to Richard Kadrey’s Damn Tumbler]


As we purchase our peek behind the curtain, we might note that it was on this date in 1923 that Albert Eistein demonstrated that time is relative:  he delivered his Nobel Prize lecture… two years late.


Written by LW

July 11, 2013 at 1:01 am

Relatively speaking…

Max Fleischer and his lady love (source)

Max Fleischer and his brother Dave were giants in the history of animation.  The most significant competition to Walt Disney in the formative years of the art, they created Betty Boop and Koko the Clown, and brought Bimbo, Popeye, Superman, and Gulliver’s Travels to the screen.  Along the way, they invented a number of technologies and techniques that have become essential to the form.

Rotoscope by Max Fleischer, patent drawing from 1914

But possibly the the strangest– and arguably the most wonderful– thing they ever did was this 1923 short film blithely and elegantly explaining the concept of relativity:

TotH to Curiosity Counts.

As we await the animators of our new paradigms, we might wish a minimal(ist) birthday to Philip Glass, award-winning composer and first cousin once removed of (R)D friend and hero Ira Glass; Philip was born on this date in 1937.

Philip Glass




Playing the odds…

A P value is the probability of an observed (or more extreme) result arising only from chance.

It’s science’s dirtiest secret: The “scientific method” of testing hypotheses by statistical analysis stands on a flimsy foundation. Statistical tests are supposed to guide scientists in judging whether an experimental result reflects some real effect or is merely a random fluke, but the standard methods mix mutually inconsistent philosophies and offer no meaningful basis for making such decisions. Even when performed correctly, statistical tests are widely misunderstood and frequently misinterpreted. As a result, countless conclusions in the scientific literature are erroneous, and tests of medical dangers or treatments are often contradictory and confusing.

Replicating a result helps establish its validity more securely, but the common tactic of combining numerous studies into one analysis, while sound in principle, is seldom conducted properly in practice.

Experts in the math of probability and statistics are well aware of these problems and have for decades expressed concern about them in major journals. Over the years, hundreds of published papers have warned that science’s love affair with statistics has spawned countless illegitimate findings. In fact, if you believe what you read in the scientific literature, you shouldn’t believe what you read in the scientific literature.

“There is increasing concern,” declared epidemiologist John Ioannidis in a highly cited 2005 paper in PLoS Medicine, “that in modern research, false findings may be the majority or even the vast majority of published research claims.”

Ioannidis claimed to prove that more than half of published findings are false, but his analysis came under fire for statistical shortcomings of its own. “It may be true, but he didn’t prove it,” says biostatistician Steven Goodman of the Johns Hopkins University School of Public Health. On the other hand, says Goodman, the basic message stands. “There are more false claims made in the medical literature than anybody appreciates,” he says. “There’s no question about that.”

Nobody contends that all of science is wrong, or that it hasn’t compiled an impressive array of truths about the natural world. Still, any single scientific study alone is quite likely to be incorrect, thanks largely to the fact that the standard statistical system for drawing conclusions is, in essence, illogical. “A lot of scientists don’t understand statistics,” says Goodman. “And they don’t understand statistics because the statistics don’t make sense”…

What’s one to make of the stream of “eat this,” “avoid that” studies surfacing nearly daily?  It’s an odds-on bet that readers will find out in the complete Science News story, “Odds Are, It’s Wrong.”

As we tell Monty that we’ll take what’s behind Door #2, we might recall that it was on this date in 1905 that Albert Einstein kicked off  “Annus Mirabilis” with the publication of the first of his four epoch-making papers in Annalen der Physik— this one, proposing energy “quanta”– thus kicking off the year in which he reinvented physics and our understanding of reality.

The second of those papers, on Brownian motion, was the very first work of “statistical physics.”

Einstein, dressed for the patent office, 1905

Happy Náw-Rúz! This date in 1844 was the first day of the first year of the Bahai calendar.

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