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Posts Tagged ‘Cosmology

“There is a size at which dignity begins”*…

 

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The spectrometer for the KATRIN experiment, as it works its way through the German town of Eggenstein-Leopoldshafen in 2006 en route to the nearby Karlsruhe Institute of Technology

 

Isaac Asimov dubbed neutrinos “ghost particles.” John Updike immortalized them in verse. They’ve been the subject of several Nobel Prize citations, because these weird tiny particles just keep surprising physicists. And now we have a much better idea of the upper limit of what their rest mass could be, thanks to the first results from the Karlsruhe Tritium Neutrino experiment (KATRIN) in Germany. Leaders from the experiment announced their results last week at a scientific conference in Japan and posted a preprint to the physics arXiv.

“Knowing the mass of the neutrino will allow scientists to answer fundamental questions in cosmology, astrophysics, and particle physics, such as how the universe evolved or what physics exists beyond the Standard Model,” said Hamish Robertson, a KATRIN scientist and professor emeritus of physics at the University of Washington…

Physicists get small: “Weighing in: Physicists cut upper limit on neutrino’s mass in half.”

* Thomas Hardy, “Two on a Tower”

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As we step onto the scales, we might spare a thought for Max Karl Ernst Ludwig Planck; he died on this date in 1947.  A theoretical physicist, he is best remembered as the originator of quantum theory.  It was his discovery of energy quanta that won him the Nobel Prize in Physics in 1918.

220px-Max_Planck_1933 source

 

Written by LW

October 4, 2019 at 1:01 am

“Toto, I’ve a feeling we’re not in Kansas anymore”*…

 

Matrix

 

in Pensées (1670), Blaise Pascal famously outlined a proposition that has become known as “Pascal’s Wager”:

If there is a God, He is infinitely incomprehensible, since, having, neither parts nor limits, He has no affinity to us. We are then incapable of knowing either what He is or if He is…  [so] belief is a wise wager. Granted that faith cannot be proved, what harm will come to you if you gamble on its truth and it proves false? If you gain, you gain all; if you lose, you lose nothing. Wager, then, without hesitation, that He exists.

In last Sunday’s New York Times, philosophy professor Preston Greene updates– and inverts– Pascal’s logic.  Noting that scientists are proposing an experimental test of Oxford professor Nick Bostrom‘s assertion that we are living in an elaborate simulation, Greene argues strongly against it…

So far, none of these experiments has been conducted, and I hope they never will be. Indeed, I am writing to warn that conducting these experiments could be a catastrophically bad idea — one that could cause the annihilation of our universe.Think of it this way. If a researcher wants to test the efficacy of a new drug, it is vitally important that the patients not know whether they’re receiving the drug or a placebo. If the patients manage to learn who is receiving what, the trial is pointless and has to be canceled.

In much the same way, as I argue in a forthcoming paper in the journal Erkenntnis, if our universe has been created by an advanced civilization for research purposes, then it is reasonable to assume that it is crucial to the researchers that we don’t find out that we’re in a simulation. If we were to prove that we live inside a simulation, this could cause our creators to terminate the simulation — to destroy our world.Of course, the proposed experiments may not detect anything that suggests we live in a computer simulation. In that case, the results will prove nothing. This is my point: The results of the proposed experiments will be interesting only when they are dangerous. While there would be considerable value in learning that we live in a computer simulation, the cost involved — incurring the risk of terminating our universe — would be many times greater…

As far as I am aware, no physicist proposing simulation experiments has considered the potential hazards of this work. This is surprising, not least because Professor Bostrom himself explicitly identified “simulation shutdown” as a possible cause of the extinction of all human life.

This area of academic research is rife with speculation and uncertainty, but one thing is for sure: If scientists do go ahead with these simulation experiments, the results will be either extremely uninteresting or spectacularly dangerous. Is it really worth the risk?

The piece in full: “Are We Living in a Computer Simulation? Let’s Not Find Out.”

[Image above, The Matrix, back in theaters on the occasion of its 20th anniversary]

* The Wizard of Oz

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As we rethink reality, we might send elastic birthday greetings to Peter Hodgson; he was born on this date in 1912.  An advertising and marketing consultant, Hodgson introduced Silly Putty to the world.  As The New York Times recounted in his obituary,

The stuff had been developed by General Electric scientists in the company’s New Haven laboratories several years earlier in a search for a viable synthetic rubber. It was obviously not satisfactory, and it found its way instead onto the local cocktail party circuit.

That’s where Mr. Hodgson, who was at the time writing a catalogue of toys for a local store, saw it, and an idea was born.

“Everybody kept saying there was no earthly use for the stuff” he later recalled. “But I watched them as they fooled with it. I couldn’t help noticing how people with busy schedules wasted as much as 15 minutes at a shot just fondling and stretching it”.

“I decided to take a chance and sell some. We put an ad in the catalogue on the adult page, along with such goodies as a spaghetti-making machine. We packaged the goop in a clear compact case and tagged it at $1.00”.

Having borrowed $147 for the venture, Mr. Hodgson ordered a batch from General Electric, hired a Yale student to separate the gob into one ounce dabs and began filling orders. At the same time he hurried to get some trademarks.

Silly Putty was an instant success, and Mr. Hodgson quickly geared up to take advantage of it…

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Written by LW

August 15, 2019 at 1:01 am

“Why should things be easy to understand?”*…

 

Lee-Smolin_2K_02

 

The universe is kind of an impossible object. It has an inside but no outside; it’s a one-sided coin. This Möbius architecture presents a unique challenge for cosmologists, who find themselves in the awkward position of being stuck inside the very system they’re trying to comprehend.

It’s a situation that Lee Smolin has been thinking about for most of his career. A physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, Smolin works at the knotty intersection of quantum mechanics, relativity and cosmology. Don’t let his soft voice and quiet demeanor fool you — he’s known as a rebellious thinker and has always followed his own path. In the 1960s Smolin dropped out of high school, played in a rock band called Ideoplastos, and published an underground newspaper. Wanting to build geodesic domes like R. Buckminster Fuller, Smolin taught himself advanced mathematics — the same kind of math, it turned out, that you need to play with Einstein’s equations of general relativity. The moment he realized this was the moment he became a physicist. He studied at Harvard University and took a position at the Institute for Advanced Study in Princeton, New Jersey, eventually becoming a founding faculty member at the Perimeter Institute.

“Perimeter,” in fact, is the perfect word to describe Smolin’s place near the boundary of mainstream physics. When most physicists dived headfirst into string theory, Smolin played a key role in working out the competing theory of loop quantum gravity. When most physicists said that the laws of physics are immutable, he said they evolve according to a kind of cosmic Darwinism. When most physicists said that time is an illusion, Smolin insisted that it’s real.

Smolin often finds himself inspired by conversations with biologists, economists, sculptors, playwrights, musicians and political theorists. But he finds his biggest inspiration, perhaps, in philosophy — particularly in the work of the German philosopher Gottfried Leibniz, active in the 17th and 18th centuries, who along with Isaac Newton invented calculus. Leibniz argued (against Newton) that there’s no fixed backdrop to the universe, no “stuff” of space; space is just a handy way of describing relationships. This relational framework captured Smolin’s imagination, as did Leibniz’s enigmatic text The Monadology, in which Leibniz suggests that the world’s fundamental ingredient is the “monad,” a kind of atom of reality, with each monad representing a unique view of the whole universe. It’s a concept that informs Smolin’s latest work as he attempts to build reality out of viewpoints, each one a partial perspective on a dynamically evolving universe. A universe as seen from the inside…

Lee Smolin explains his radical idea for how to understand an object with no exterior–imagine it built bit-by-bit from relationships between events: “How to Understand the Universe When You’re Stuck Inside of It.”

* Thomas Pynchon

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As we muse on monads, we might send delightful birthday greetings to Fernando Arrabal Terán; he was born on this date in 1932.  A playwright, screenwriter, film director, novelist, and poet, Arrabal co-founded the Panic Movement with Alejandro Jodorowsky and Roland Topor (inspired by the god Pan).

Early in his career, he spent three years as a member of André Breton’s surrealist group and was a friend of Andy Warhol and Tristan Tzara.  Later (in 1990), he was elected Transcendent Satrap of the Collège de  ‘pataphysique (following such predecessors as Marcel Duchamp, Eugène Ionesco, Man Ray, Boris Vian, Dario Fo, Umberto Eco, and Jean Baudrillard).

And throughout, he was very productive: Arrabal has directed seven full-length feature films and has published over 100 plays; 14 novels; 800 poetry collections, chapbooks, and artists’ books; several essays; and his notorious “Letter to General Franco” during the dictator’s lifetime.  His complete plays have been published, in multiple languages, in a two-volume edition totaling over two thousand pages. The New York Times theater critic Mel Gussow has called Arrabal the last survivor among the “three avatars of modernism.”

200px-Fernando_Arrabal,_2012 source

 

 

Written by LW

August 11, 2019 at 1:01 am

“I think I can safely say that nobody understands quantum mechanics”*…

 

Quantum_Darwinism_2880x1620_Lede

 

But we may be getting a little bit closer…

It’s not surprising that quantum physics has a reputation for being weird and counterintuitive. The world we’re living in sure doesn’t feel quantum mechanical. And until the 20th century, everyone assumed that the classical laws of physics devised by Isaac Newton and others — according to which objects have well-defined positions and properties at all times — would work at every scale. But Max Planck, Albert Einstein, Niels Bohr and their contemporaries discovered that down among atoms and subatomic particles, this concreteness dissolves into a soup of possibilities. An atom typically can’t be assigned a definite position, for example — we can merely calculate the probability of finding it in various places. The vexing question then becomes: How do quantum probabilities coalesce into the sharp focus of the classical world?

Physicists sometimes talk about this changeover as the “quantum-classical transition.” But in fact there’s no reason to think that the large and the small have fundamentally different rules, or that there’s a sudden switch between them. Over the past several decades, researchers have achieved a greater understanding of how quantum mechanics inevitably becomes classical mechanics through an interaction between a particle or other microscopic system and its surrounding environment.

One of the most remarkable ideas in this theoretical framework is that the definite properties of objects that we associate with classical physics — position and speed, say — are selected from a menu of quantum possibilities in a process loosely analogous to natural selection in evolution: The properties that survive are in some sense the “fittest.” As in natural selection, the survivors are those that make the most copies of themselves. This means that many independent observers can make measurements of a quantum system and agree on the outcome — a hallmark of classical behavior.

This idea, called quantum Darwinism (QD), explains a lot about why we experience the world the way we do rather than in the peculiar way it manifests at the scale of atoms and fundamental particles. Although aspects of the puzzle remain unresolved, QD helps heal the apparent rift between quantum and classical physics.

Only recently, however, has quantum Darwinism been put to the experimental test…

How do quantum possibilities give rise to objective, classical reality?  More on one possible explanation, quantum Darwinism– and on the three experiments that have have begun to vet the theory: “Quantum Darwinism, an Idea to Explain Objective Reality, Passes First Tests.”

* Richard Feynman

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As we ruminate on reality, we might recall that it was on this date in 1975 that Jimmy Hoffa disappeared from the parking lot of the Machus Red Fox restaurant in Bloomfield Hills, Michigan, a suburb of Detroit, at about 2:30 p.m.  He was never seen or heard from again.

Hoffa had served as President of the International Brotherhood of Teamsters from 1957.  Long suspected of mob ties, he was convicted of jury tampering, attempted bribery and fraud in 1964, and sentenced to 13 years in prison in 1967… from whence he continued in his union office until 1972, when he was pardoned by President Richard Nixon on the condition that he resign Teamsters office.  Out of jail, he began to plot an attempt to reverse this condition and return to power.  Before he could make much progress, he disappeared.  He was declared legally dead in 1982.  While there has never been an official explanation of Hoffa’s demise, it is widely believed that he was killed by the Mafia, which was uncomfortable with his efforts to disrupt the power structure of the Teamsters (over which they has reestablished control).

220px-James_R._Hoffa_NYWTS source

 

Written by LW

July 30, 2019 at 1:01 am

“There are two things you should remember when dealing with parallel universes. One, they’re not really parallel, and two, they’re not really universes.”*…

 

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At Oak Ridge National Laboratory in eastern Tennessee, physicist Leah Broussard is trying to open a portal to a parallel universe.

She calls it an “oscillation” that would lead her to “mirror matter,” but the idea is fundamentally the same. In a series of experiments she plans to run at Oak Ridge this summer, Broussard will send a beam of subatomic particles down a 50-foot tunnel, past a powerful magnet and into an impenetrable wall. If the setup is just right — and if the universe cooperates — some of those particles will transform into mirror-image versions of themselves, allowing them to tunnel right through the wall. And if that happens, Broussard will have uncovered the first evidence of a mirror world right alongside our own.

“It’s pretty wacky,” Broussard says of her mind-bending exploration.

The mirror world, assuming it exists, would have its own laws of mirror-physics and its own mirror-history. You wouldn’t find a mirror version of yourself there (and no evil Spock with a goatee — sorry “Star Trek” fans). But current theory allows that you might find mirror atoms and mirror rocks, maybe even mirror planets and stars. Collectively, they could form an entire shadow world, just as real as our own but almost completely cut off from us…

If the “mirrorverse” exists, upcoming experiments involving subatomic particles could reveal it: “Scientists are searching for a mirror universe. It could be sitting right in front of you.”

* Douglas Adams

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As we reflect of reflections, we might recall that it was on this date in 64 CE that the Great Fire of Rome began, ultimately destroying much of the Imperial City.  The fire began in the slums of a district south of the Palatine Hill.  The area’s homes burned very quickly and the fire spread north, fueled by high winds; it raged out of control for three days.  Three of Rome’s 14 districts were completely razed; only four were untouched by the conflagration.  Hundreds of people died in the fire and many thousands were left homeless.

Legend has it that the Emperor Nero fiddled while the city burned.  But the fiddle did not even exist at the time (Nero was an adept of the lyre), and he was actually 35 miles away in Antium when the fire broke out.  What is clear is that he blamed “the Christians” for it.

800px-Robert,_Hubert_-_Incendie_à_Rome_-

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Written by LW

July 19, 2019 at 1:01 am

“Behind the hieroglyphic streets there would either be a transcendent meaning, or only the earth”*…

 

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A map from 1893 portrays Earth as square and stationary and warns of Biblical interdiction against the notion of a round Earth flying through space

 

If you are only just waking up to the twenty-first century, you should know that, according to a growing number of people, much of what you’ve been taught about our planet is a lie: Earth really is flat. We know this because dozens, if not hundreds, of YouTube videos describe the coverup. We’ve listened to podcasts—Flat Earth Conspiracy, The Flat Earth Podcast—that parse the minutiae of various flat-Earth models, and the very wonkiness of the discussion indicates that the over-all theory is as sound and valid as any other scientific theory. We know because on a clear, cool day it is sometimes possible, from southwestern Michigan, to see the Chicago skyline, more than fifty miles away—an impossibility were Earth actually curved. We know because, last February, Kyrie Irving, the Boston Celtics point guard, told us so. “The Earth is flat,” he said. “It’s right in front of our faces. I’m telling you, it’s right in front of our faces. They lie to us.” We know because, last November, a year and a day after Donald Trump was elected President, more than five hundred people from across this flat Earth paid as much as two hundred and forty-nine dollars each to attend the first-ever Flat Earth Conference, in a suburb of Raleigh, North Carolina…

The unsettling thing about spending two days at a convention of people who believe that Earth is flat isn’t the possibility that you, too, might come to accept their world view, although I did worry a little about that. Rather, it’s the very real likelihood that, after sitting through hours of presentations on “scientism,” lightning angels, and NASA’s many conspiracies—the moon-landing hoax, the International Fake Station, so-called satellites—and in chatting with I.T. specialists, cops, college students, and fashionably dressed families with young children, all of them unfailingly earnest and lovely, you will come to actually understand why a growing number of people are dead certain that Earth is flat. Because that truth is unnerving…

Alan Burdick explains what the burgeoning movement says about science, solace, and how a theory becomes truth; “Looking for Life on a Flat Earth.”

* Thomas Pynchon, The Crying of Lot 49

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As we contemplate curvature, we might recall that it was on this date in 1850 that Harvard Observatory director William Cranch Bond and Boston photographer John Adams Whipple took a daguerreotype of Vega– the first photograph of a star ever made.

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“The Universe is under no obligation to make sense to you”*…

 

bubble

Uppsala University researchers have devised a new model for the Universe – one that may solve the enigma of dark energy. Their new article, published in Physical Review Letters, proposes a new structural concept, including dark energy, for a universe that rides on an expanding bubble in an additional dimension.

We have known for the past 20 years that the Universe is expanding at an ever accelerating rate. The explanation is the “dark energy” that permeates it throughout, pushing it to expand. Understanding the nature of this dark energy is one of the paramount enigmas of fundamental physics.

It has long been hoped that string theory will provide the answer. According to string theory, all matter consists of tiny, vibrating “stringlike” entities. The theory also requires there to be more spatial dimensions than the three that are already part of everyday knowledge. For 15 years, there have been models in string theory that have been thought to give rise to dark energy. However, these have come in for increasingly harsh criticism, and several researchers are now asserting that none of the models proposed to date are workable.

In their article, the scientists propose a new model with dark energy and our Universe riding on an expanding bubble in an extra dimension. The whole Universe is accommodated on the edge of this expanding bubble. All existing matter in the Universe corresponds to the ends of strings that extend out into the extra dimension. The researchers also show that expanding bubbles of this kind can come into existence within the framework of string theory. It is conceivable that there are more bubbles than ours, corresponding to other universes.

The Uppsala scientists’ model provides a new, different picture of the creation and future fate of the Universe, while it may also pave the way for methods of testing string theory…

Via AAAS Eureka Alerts

(For a different emerging new theory– that may or may not be contradictory– see “Our universe has antimatter partner on the other side of the Big Bang.”)

* Neil deGrasse Tyson

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As we fumble with the fundamentals, we might send carefully-deduced birthday greetings to Richard Bevan Braithwaite; he was born on this date in 1900.  A Cambridge philosopher who specialized in the philosophy of science, he focused on the logical features common to all sciences.  Braithwaite was concerned with the impact of science on our beliefs about the world and the appropriate responses to that impact.  He was especially interested in probability (and its applications in decision theory and games theory) and in the statistical sciences.  He was president of the Aristotelian Society from 1946 to 1947, and was a Fellow of the British Academy.

It was Braithwaite’s poker that Ludwig Wittgenstein reportedly brandished at Karl Popper during their confrontation at a Moral Sciences Club meeting in Braithwaite’s rooms in King’s. The implement subsequently disappeared. (See here.)

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Written by LW

January 15, 2019 at 1:01 am

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