Tag Archives: Marina Koren

Donna Strickland, first female Nobel Prize winner in 55 years and one of only three (so far) in history

It’s been quite the fascinating week in the world of physics culminating with Donna Strickland’s shiny new Nobel Prize in physics.

For my purposes, this week in physics started on Friday, September 28, 2018 with Allesanndro Strumia’s presentation at CERN’s (European Particle Physics Laboratory) “1st workshop on high energy theory and gender” where he claimed and proved ‘scientifically’ that physics has become “sexist against men.” I’ll get back to Strumia in a moment but, first, let’s celebrate Donna Strickland and her achievements.

Only three women, including Strickland, in the history (117 years) of the Nobel Prize for Physics have won it, Marie Curie in 1903, Maria Goeppert Mayer in 1963, and, now, Strickland in 2018.

The University of Waterloo (Ontario, Canada) had this to say in an October 2, 2018 news release,

Donna Strickland wins Nobel Prize in Physics

Tuesday, October 2, 2018

Dr. Donna Strickland

Donna Strickland, a University of Waterloo professor who helped revolutionize laser physics, has been named a winner of this year’s Nobel Prize in Physics.

Strickland, an associate professor in the Department of Physics and Astronomy, shares half the $1.4 million prize with French laser physicist Gérard Mourou. The other half was awarded to U.S. physicist Arthur Ashkin.

The Royal Swedish Academy of Sciences stated that Mourou and Strickland paved the way toward the shortest and most intense laser pulses created by mankind. Their revolutionary article was published in 1985 and was the foundation of Strickland’s doctoral thesis.

Strickand conducted her Nobel-winning research while a PhD student under Mourou in 1989 at the University of Rochester in New York. The team’s research has a number of applications in industry and medicine.

It was great to have had the opportunity to work with one of the pioneers of ultrafast lasers, Gerard Mourou,” said Strickland. “It was a small community back then. It was a new, burgeoning field. I got to be part of that. It was very exciting.”

A Nobel committee member said billions of people make daily use of laser printers and optical scanners and millions undergo laser surgery.

“This is a tremendous day for Professor Strickland and needless to say a tremendous day for the University of Waterloo,” said Feridun Hamdullahpur, president and vice-chancellor of the University of Waterloo. “This is Waterloo’s first Nobel laureate and the first woman to receive the Nobel Prize in Physics in 55 years.”

During an interview, Strickland told the Globe and Mail [national newspaper]: “We need to celebrate women physicists because we’re out there, and hopefully in time it’ll start to move forward at a faster rate.”

Charmaine Dean, vice-president research at the University of Waterloo said: “Donna Strickland exemplifies research excellence at Waterloo. Her groundbreaking work is a testament to the importance of fundamental research as it has established the foundation for laser-based technologies that we see today from micromachining to laser eye surgery.”

An October 2, 2018 news item on Nanowerk focuses on the three winners,

Arthur Ashkin, an American physicist has been awarded half the prize for his invention of optical tweezers and their application to biological systems. His amazing tool has helped to reach the old dream of grabing [sic] particles, atoms, viruses and other living cells. The optical tweezers work with the radiation pressure of light to hold and move tiny object and are widely used to study the machinery of life.

French physicist Gérard Mourou and Canadian physicist Donna Strickland share the other half for their method of generating ultra-short and very intense optical pulses. Ultra-sharp laser beams have made possible to cut or drill holes in various materials extremely precisely – even in living matter. The technique this duo pioneered is called chirped pulse amplification or CPA and it has led to corrective eye surgeries for millions of people.

An Oct. 2, 2018 article by Marina Koren for The Atlantic is my favourite of the ones focusing on Strickland. One of Koren’s major focal points is Strickland’s new Wikipedia page (Note: Links have been removed),

It was about five in the morning in Ontario, Canada, when Donna Strickland’s phone rang. The Nobel Prize committee was on the line in Stockholm, calling to tell her she had won the prize in physics.

“We wondered if it was a prank,” Strickland said Tuesday [October 2 ,2018], in an interview with a Nobel official after the call. She had been asleep when the call arrived. “But then I knew it was the right day, and it would have been a cruel prank.”

Lasers, focused beams of light particles, were invented in the 1960s. Scientists immediately started tinkering with them, looking for ways to harness and manipulate these powerful devices.

Strickland and [Gérard] Mourou] found a way to stretch and compress lasers to produce short, intense pulses that are now used, among other things, in delicate surgeries to fix vision problems. [Arthur] Ashkin figured out a way to maneuver laser light so that it could push small particles toward the center of the beam, hold them in place, and even move them around. This technique became the delightfully named “optical tweezer.” It allowed Ashkin to use the power of light to capture and hold living bacteria and viruses without harming the organisms.

Unlike her fellow winners, Strickland did not have a Wikipedia page at the time of the announcement. A Wikipedia user tried to set up a page in May, but it was denied by a moderator with the message: “This submission’s references do not show that the subject qualifies for a Wikipedia article.” Strickland, it was determined, had not received enough dedicated coverage elsewhere on the internet to warrant a page.

On Tuesday, a newly created page flooded with edits: “Added in her title.” “Add Nobel-winning paper.” “Added names of other women Nobelists [sic] in physics.”

The construction of the Wikipedia page feels like a metaphor for a historic award process that has long been criticized for neglecting women in its selection, and for the shortage of women’s stories in the sciences at large. To scroll through the “history” tab of Strickland’s page, where all edits are recorded and tracked, is to witness in real time the recognition of a scientist whose story likely deserved attention long before the Nobel Prize committee called.

Strickland’s historic win comes a day after CERN, the European organization that operates the world’s most powerful particle accelerator, suspended a senior scientist for saying that physics was “invented and built by men.” Alessandro Strumia, a professor at the University of Pisa, made the statement during a recent speech at a seminar on gender issues in physics that was attended by mostly female physicists. Strumia said “men prefer working with things and women prefer working with people,” and that between men and women there is a “difference even in children before any social influence.” His remarks were widely circulated online and prompted fierce backlash.

The remarks don’t faze Strickland, who very publicly proved them wrong on Tuesday. In an interview with the BBC on Tuesday, she called Strumia’s claims “silly.”

For anyone curious about the Strumia situation, there’s an October 2, 2018 CBC Radio (As It Happens) online news article. Note: Links have been removed,

Not only was Alessandro Strumia being offensive when he said that physics “was invented and built by men” — he was also wrong, says physicist Jess Wade.

“Actually, women have contributed hugely to physics throughout the whole of history, but for an incredibly long time we haven’t documented or told those stories,” Wade told As It Happens host Carol Off.

And she would know. The Imperial College London research associate has made it her mission to write hundreds of Wikipedia entries about women in science and engineering.

Wade was in the room on Friday when Strumia, a physicist at Pisa University, made the inflammatory remarks during a gender workshop in Geneva, organized by the European nuclear research centre CERN.

CERN cut ties with Strumia after the BBC reported the content of his presentation.

This article includes some of the slides in Strumia’s now infamous presentation.

Tommaso Dorigo in an October 1, 2018 posting on the Science 2.0 blog offers another analysis,

The world of particle physics is in turmoil because of a presentation by Alessandro Strumia, an Italian phenomenologist, at CERN’s “1st workshop on high energy theory and gender”, and its aftermath.

By now the story has been echoed by many major newscasters around the world, and discussed in public and private forums, blogs, twitter feeds. I wanted to stay away from it here, mainly because it is a sensitive issue and the situation is still evolving, but after all, why not offer to you my personal pitch on the matter? Strumia, by the way, has been an occasional commenter to this blog – you can find some of his comments signed as “AS” in threads of past articles. Usually he makes good points here, as long as physics is the subject.

Anyway, first of all let me give you a quick recall of the events. The three-day workshop, which took place on September 26-28, was meant to”focus on recent developments in theoretical high-energy physics and cosmology, and discuss issues of gender and equal opportunities in the field“; it followed three previous events which combined string theory and gender issues. Strumia’s presentation was titled “Experimental tests of a new global symmetry“, a physicist’s way of describing the issue of man-woman equality. It is important to note that the talk was not an invited one – its author had asked the organizers for a slot as he said he would be talking of bibliometrics, and indeed his contribution was listed in the agenda of September 28 with the innocuous title “Bibliometrics data about gender issues in fundamental theory“.

Strumia’s slides contain a collection of half-baked claims, coming from his analysis of InSpire data from citations and authorship of articles in theoretical physics. I consider his talk offensive on many levels. It starts by casting the woman discrimination issue in scientific academia as a test of hypothesis of whether the “man-woman” symmetry is explicitly broken (i.e. there is no symmetry) or spontaneously broken (by a difference of treatment) – something that could even raise a smile in a geeky physicist; but the fun ends there.

Dorigo offers a detailed ‘takedown’ of Strumia’s assertions. I found the post intriguing for the insight it offers into physics. Never in a million years would I have thought this title, “Experimental tests of a new global symmetry,” would indicate a discussion on gender balance in the field of physics.

As I said in the opening, it has been quite the week in physics. On a final note, Brava to Doctor Donna Strickland!

Gold’s origin in the universe due to cosmic collision

An hypothesis for gold’s origins was first mentioned here in a May 26, 2016 posting,

The link between this research and my side project on gold nanoparticles is a bit tenuous but this work on the origins for gold and other precious metals being found in the stars is so fascinating and I’m determined to find a connection.

An artist's impression of two neutron stars colliding. (Credit: Dana Berry / Skyworks Digital, Inc.) Courtesy: Kavli Foundation

An artist’s impression of two neutron stars colliding. (Credit: Dana Berry / Skyworks Digital, Inc.) Courtesy: Kavli Foundation

From a May 19, 2016 news item on phys.org,

The origin of many of the most precious elements on the periodic table, such as gold, silver and platinum, has perplexed scientists for more than six decades. Now a recent study has an answer, evocatively conveyed in the faint starlight from a distant dwarf galaxy.

In a roundtable discussion, published today [May 19, 2016?], The Kavli Foundation spoke to two of the researchers behind the discovery about why the source of these heavy elements, collectively called “r-process” elements, has been so hard to crack.

From the Spring 2016 Kavli Foundation webpage hosting the  “Galactic ‘Gold Mine’ Explains the Origin of Nature’s Heaviest Elements” Roundtable ,

Astronomers studying a galaxy called Reticulum II have just discovered that its stars contain whopping amounts of these metals—collectively known as “r-process” elements (See “What is the R-Process?”). Of the 10 dwarf galaxies that have been similarly studied so far, only Reticulum II bears such strong chemical signatures. The finding suggests some unusual event took place billions of years ago that created ample amounts of heavy elements and then strew them throughout the galaxy’s reservoir of gas and dust. This r-process-enriched material then went on to form Reticulum II’s standout stars.

Based on the new study, from a team of researchers at the Kavli Institute at the Massachusetts Institute of Technology, the unusual event in Reticulum II was likely the collision of two, ultra-dense objects called neutron stars. Scientists have hypothesized for decades that these collisions could serve as a primary source for r-process elements, yet the idea had lacked solid observational evidence. Now armed with this information, scientists can further hope to retrace the histories of galaxies based on the contents of their stars, in effect conducting “stellar archeology.”

Researchers have confirmed the hypothesis according to an Oct. 16, 2017 news item on phys.org,

Gold’s origin in the Universe has finally been confirmed, after a gravitational wave source was seen and heard for the first time ever by an international collaboration of researchers, with astronomers at the University of Warwick playing a leading role.

Members of Warwick’s Astronomy and Astrophysics Group, Professor Andrew Levan, Dr Joe Lyman, Dr Sam Oates and Dr Danny Steeghs, led observations which captured the light of two colliding neutron stars, shortly after being detected through gravitational waves – perhaps the most eagerly anticipated phenomenon in modern astronomy.

Marina Koren’s Oct. 16, 2017 article for The Atlantic presents a richly evocative view (Note: Links have been removed),

Some 130 million years ago, in another galaxy, two neutron stars spiraled closer and closer together until they smashed into each other in spectacular fashion. The violent collision produced gravitational waves, cosmic ripples powerful enough to stretch and squeeze the fabric of the universe. There was a brief flash of light a million trillion times as bright as the sun, and then a hot cloud of radioactive debris. The afterglow hung for several days, shifting from bright blue to dull red as the ejected material cooled in the emptiness of space.

Astronomers detected the aftermath of the merger on Earth on August 17. For the first time, they could see the source of universe-warping forces Albert Einstein predicted a century ago. Unlike with black-hole collisions, they had visible proof, and it looked like a bright jewel in the night sky.

But the merger of two neutron stars is more than fireworks. It’s a factory.

Using infrared telescopes, astronomers studied the spectra—the chemical composition of cosmic objects—of the collision and found that the plume ejected by the merger contained a host of newly formed heavy chemical elements, including gold, silver, platinum, and others. Scientists estimate the amount of cosmic bling totals about 10,000 Earth-masses of heavy elements.

I’m not sure exactly what this image signifies but it did accompany Koren’s article so presumably it’s a representation of colliding neutron stars,

NSF / LIGO / Sonoma State University /A. Simonnet. Downloaded from: https://www.theatlantic.com/science/archive/2017/10/the-making-of-cosmic-bling/543030/

An Oct. 16, 2017 University of Warwick press release (also on EurekAlert), which originated the news item on phys.org, provides more detail,

Huge amounts of gold, platinum, uranium and other heavy elements were created in the collision of these compact stellar remnants, and were pumped out into the universe – unlocking the mystery of how gold on wedding rings and jewellery is originally formed.

The collision produced as much gold as the mass of the Earth. [emphasis mine]

This discovery has also confirmed conclusively that short gamma-ray bursts are directly caused by the merging of two neutron stars.

The neutron stars were very dense – as heavy as our Sun yet only 10 kilometres across – and they collided with each other 130 million years ago, when dinosaurs roamed the Earth, in a relatively old galaxy that was no longer forming many stars.

They drew towards each other over millions of light years, and revolved around each other increasingly quickly as they got closer – eventually spinning around each other five hundred times per second.

Their merging sent ripples through the fabric of space and time – and these ripples are the elusive gravitational waves spotted by the astronomers.

The gravitational waves were detected by the Advanced Laser Interferometer Gravitational-Wave Observatory (Adv-LIGO) on 17 August this year [2017], with a short duration gamma-ray burst detected by the Fermi satellite just two seconds later.

This led to a flurry of observations as night fell in Chile, with a first report of a new source from the Swope 1m telescope.

Longstanding collaborators Professor Levan and Professor Nial Tanvir (from the University of Leicester) used the facilities of the European Southern Observatory to pinpoint the source in infrared light.

Professor Levan’s team was the first one to get observations of this new source with the Hubble Space Telescope. It comes from a galaxy called NGC 4993, 130 million light years away.

Andrew Levan, Professor in the Astronomy & Astrophysics group at the University of Warwick, commented: “Once we saw the data, we realised we had caught a new kind of astrophysical object. This ushers in the era of multi-messenger astronomy, it is like being able to see and hear for the first time.”

Dr Joe Lyman, who was observing at the European Southern Observatory at the time was the first to alert the community that the source was unlike any seen before.

He commented: “The exquisite observations obtained in a few days showed we were observing a kilonova, an object whose light is powered by extreme nuclear reactions. This tells us that the heavy elements, like the gold or platinum in jewellery are the cinders, forged in the billion degree remnants of a merging neutron star.”

Dr Samantha Oates added: “This discovery has answered three questions that astronomers have been puzzling for decades: what happens when neutron stars merge? What causes the short duration gamma-ray bursts? Where are the heavy elements, like gold, made? In the space of about a week all three of these mysteries were solved.”

Dr Danny Steeghs said: “This is a new chapter in astrophysics. We hope that in the next few years we will detect many more events like this. Indeed, in Warwick we have just finished building a telescope designed to do just this job, and we expect it to pinpoint these sources in this new era of multi-messenger astronomy”.

Congratulations to all of the researchers involved in this work!

Many, many research teams were  involved. Here’s a sampling of their news releases which focus on their areas of research,

University of the Witwatersrand (South Africa)

https://www.eurekalert.org/pub_releases/2017-10/uotw-wti101717.php

Weizmann Institute of Science (Israel)

https://www.eurekalert.org/pub_releases/2017-10/wios-cns101717.php

Carnegie Institution for Science (US)

https://www.eurekalert.org/pub_releases/2017-10/cifs-dns101217.php

Northwestern University (US)

https://www.eurekalert.org/pub_releases/2017-10/nu-adc101617.php

National Radio Astronomy Observatory (US)

https://www.eurekalert.org/pub_releases/2017-10/nrao-ru101317.php

Max-Planck-Gesellschaft (Germany)

https://www.eurekalert.org/pub_releases/2017-10/m-gwf101817.php

Penn State (Pennsylvania State University; US)

https://www.eurekalert.org/pub_releases/2017-10/ps-stl101617.php

University of California – Davis

https://www.eurekalert.org/pub_releases/2017-10/uoc–cns101717.php

The American Association for the Advancement of Science’s (AAAS) magazine, Science, has published seven papers on this research. Here’s an Oct. 16, 2017 AAAS news release with an overview of the papers,

https://www.eurekalert.org/pub_releases/2017-10/aaft-btf101617.php

I’m sure there are more news releases out there and that there will be many more papers published in many journals, so if this interests, I encourage you to keep looking.

Two final pieces I’d like to draw your attention to: one answers basic questions and another focuses on how artists knew what to draw when neutron stars collide.

Keith A Spencer’s Oct. 18, 2017 piece on salon.com answers a lot of basic questions for those of us who don’t have a background in astronomy. Here are a couple of examples,

What is a neutron star?

Okay, you know how atoms have protons, neutrons, and electrons in them? And you know how protons are positively charged, and electrons are negatively charged, and neutrons are neutral?

Yeah, I remember that from watching Bill Nye as a kid.

Totally. Anyway, have you ever wondered why the negatively-charged electrons and the positively-charged protons don’t just merge into each other and form a neutral neutron? I mean, they’re sitting there in the atom’s nucleus pretty close to each other. Like, if you had two magnets that close, they’d stick together immediately.

I guess now that you mention it, yeah, it is weird.

Well, it’s because there’s another force deep in the atom that’s preventing them from merging.

It’s really really strong.

The only way to overcome this force is to have a huge amount of matter in a really hot, dense space — basically shove them into each other until they give up and stick together and become a neutron. This happens in very large stars that have been around for a while — the core collapses, and in the aftermath, the electrons in the star are so close to the protons, and under so much pressure, that they suddenly merge. There’s a big explosion and the outer material of the star is sloughed off.

Okay, so you’re saying under a lot of pressure and in certain conditions, some stars collapse and become big balls of neutrons?

Pretty much, yeah.

So why do the neutrons just stick around in a huge ball? Aren’t they neutral? What’s keeping them together? 

Gravity, mostly. But also the strong nuclear force, that aforementioned weird strong force. This isn’t something you’d encounter on a macroscopic scale — the strong force only really works at the type of distances typified by particles in atomic nuclei. And it’s different, fundamentally, than the electromagnetic force, which is what makes magnets attract and repel and what makes your hair stick up when you rub a balloon on it.

So these neutrons in a big ball are bound by gravity, but also sticking together by virtue of the strong nuclear force. 

So basically, the new ball of neutrons is really small, at least, compared to how heavy it is. That’s because the neutrons are all clumped together as if this neutron star is one giant atomic nucleus — which it kinda is. It’s like a giant atom made only of neutrons. If our sun were a neutron star, it would be less than 20 miles wide. It would also not be something you would ever want to get near.

Got it. That means two giant balls of neutrons that weighed like, more than our sun and were only ten-ish miles wide, suddenly smashed into each other, and in the aftermath created a black hole, and we are just now detecting it on Earth?

Exactly. Pretty weird, no?

Spencer does a good job of gradually taking you through increasingly complex explanations.

For those with artistic interests, Neel V. Patel tries to answer a question about how artists knew what draw when neutron stars collided in his Oct. 18, 2017 piece for Slate.com,

All of these things make this discovery easy to marvel at and somewhat impossible to picture. Luckily, artists have taken up the task of imagining it for us, which you’ve likely seen if you’ve already stumbled on coverage of the discovery. Two bright, furious spheres of light and gas spiraling quickly into one another, resulting in a massive swell of lit-up matter along with light and gravitational waves rippling off speedily in all directions, towards parts unknown. These illustrations aren’t just alluring interpretations of a rare phenomenon; they are, to some extent, the translation of raw data and numbers into a tangible visual that gives scientists and nonscientists alike some way of grasping what just happened. But are these visualizations realistic? Is this what it actually looked like? No one has any idea. Which is what makes the scientific illustrators’ work all the more fascinating.

“My goal is to represent what the scientists found,” says Aurore Simmonet, a scientific illustrator based at Sonoma State University in Rohnert Park, California. Even though she said she doesn’t have a rigorous science background (she certainly didn’t know what a kilonova was before being tasked to illustrate one), she also doesn’t believe that type of experience is an absolute necessity. More critical, she says, is for the artist to have an interest in the subject matter and in learning new things, as well as a capacity to speak directly to scientists about their work.

Illustrators like Simmonet usually start off work on an illustration by asking the scientist what’s the biggest takeaway a viewer should grasp when looking at a visual. Unfortunately, this latest discovery yielded a multitude of papers emphasizing different conclusions and highlights. With so many scientific angles, there’s a stark challenge in trying to cram every important thing into a single drawing.

Clearly, however, the illustrations needed to center around the kilonova. Simmonet loves colors, so she began by discussing with the researchers what kind of color scheme would work best. The smash of two neutron stars lends itself well to deep, vibrant hues. Simmonet and Robin Dienel at the Carnegie Institution for Science elected to use a wide array of colors and drew bright cracking to show pressure forming at the merging. Others, like Luis Calcada at the European Southern Observatory, limited the color scheme in favor of emphasizing the bright moment of collision and the signal waves created by the kilonova.

Animators have even more freedom to show the event, since they have much more than a single frame to play with. The Conceptual Image Lab at NASA’s [US National Aeronautics and Space Administration] Goddard Space Flight Center created a short video about the new findings, and lead animator Brian Monroe says the video he and his colleagues designed shows off the evolution of the entire process: the rising action, climax, and resolution of the kilonova event.

The illustrators try to adhere to what the likely physics of the event entailed, soliciting feedback from the scientists to make sure they’re getting it right. The swirling of gas, the direction of ejected matter upon impact, the reflection of light, the proportions of the objects—all of these things are deliberately framed such that they make scientific sense. …

Do take a look at Patel’s piece, if for no other reason than to see all of the images he has embedded there. You may recognize Aurore Simmonet’s name from the credit line in the second image I have embedded here.