Eighteen physics facilities will give photographers a behind-the-scenes look at science.
Major science laboratories from around the world today announced a Global Physics Photowalk competition that will be open to amateur and professional photographers. Physics facilities in Asia, Australia, Europe and North America will open their doors for a rare opportunity to see behind the scenes of some of the world’s most exciting and ground-breaking science.
The photowalk will involve local and national competitions, with the winning national photos submitted to a global judging panel. The program is organized by the Interactions Collaboration and supported by the Royal Photographic Society (RPS). The global shortlist will be announced in August, followed by a public vote.
Confirmed locations include CERN, the home of the Large Hadron Collider; underground laboratories in the US, Australia and the UK; and labs and facilities in Italy, the UK, the US, Canada, and—for the first time—China.
“This is a fantastic celebration of the stunning beauty of science on an international scale," says Mark Richardson, Chair of the RPS Science Committee. "The world’s best scientific research is based on international collaboration, a worldwide melting pot of expertise and technologies, each working for the benefit of our global society and economy. The photowalk is a rare opportunity to capture work behind the scenes at the world’s best international laboratories and capture it, frame by frame.
The international competition will include the following laboratories:
Places for each photowalk are limited and are strictly by registration only.
Details about the facilities and local photowalks can be found by clicking on the links above, and you can follow along on social media with #PhysPics18. A selection of winning images from previous photowalks is available here.
Editor's note: this article was adapted from a press release by the Interactions Collaboration.
University of Manchester’s Stefan Soldner-Rembold will join Edward Blucher of the University of Chicago as co-spokesperson.
The next two years are pivotal for the Deep Underground Neutrino Experiment, the international particle physics experiment hosted by the US Department of Energy’s Fermi National Accelerator Laboratory.
In a vote earlier this month, the DUNE collaboration elected Stefan Soldner-Rembold, professor of particle physics at the University of Manchester, as its new co-spokesperson to help guide the experiment through these next two years. Soldner-Rembold has experience leading a large collaboration—he was co-spokesperson of the 500-member DZero experiment at Fermilab from 2009 to 2011—and has been working in neutrino physics for more than a decade.
Soldner-Rembold has served in several leadership positions within the DUNE collaboration, including chair of the Speakers Committee, and was elected as a member of the DUNE Executive Committee in 2016.
Two prototype detectors for DUNE are scheduled to be completed at CERN in Switzerland later this year, and technical design on the experiment’s full-size detector will be worked out over the next 18 months. The DUNE collaboration continues to grow—it currently includes more than 1,000 members from 31 countries—and continues to attract young minds from around the world, eager to contribute to this global-scale neutrino experiment.
“This is a formative period for DUNE,” Soldner-Rembold says. “What we decide now will shape the detectors and the way the collaboration works for the next 10 to 20 years. I’m thrilled to be stepping in as co-spokesperson during such an exciting time.”
It’s also a time in which the UK’s contributions to DUNE are ramping up. The UK has committed $88 million to the construction of the experiment (including the facility that will house it and the accelerator upgrades that will power it), and Soldner-Rembold is currently leading the UK-US consortium designing and constructing vital components of the DUNE detector. Prototypes of these components are currently being installed in the ProtoDUNE detectors under construction at CERN, another major partner in DUNE.
“To build the world’s best neutrino detector, we need to attract further international partners,” Soldner-Rembold says. “The election of an international co-spokesperson sends a signal to other countries that this is an interesting and exciting project that they should join and commit to.”
Over the next few years, Soldner-Rembold says, it will be important to continue to encourage young scientists to participate in DUNE.
“In order to create a vibrant and strong collaboration, we need to encourage the next generation of young physicists to be engaged with the project,” he says.
Soldner-Rembold will take over the position from Mark Thomson of the University of Cambridge and will join Edward Blucher of the University of Chicago as co-spokesperson.
“I look forward to working closely with Stefan,” Blucher says. “His wealth of experience will prove invaluable as the DUNE collaboration navigates the exciting years ahead.”
The touring Tactile Collider event explores new ways to access Large Hadron Collider science through touch, sound and live interaction.
The world of particle physics is invisible to the naked eye, existing at a scale that’s almost inconceivably small. Stacked on top of each other, a trillion protons—particles found in an atom’s nucleus—would reach just 1 millimeter high. Physicists build tools to “see” this world, making it visible through data and charts.
In a new project in the United Kingdom, three scientists are reimagining how to represent subatomic life and explain fundamental ideas in a new way. The traveling event, called Tactile Collider, uses touch, sound and live interaction to bring the world of these tiny particles to students and others who are blind and visually impaired.
“I’ve spoken to a lot of people who thought science wasn’t for them, and we wanted to show that it could be,” says Chris Edmonds, a physics lecturer at the University of Liverpool and one of the project’s founders. “We can tell the story in a very different way. We wanted people to leave feeling that they could take this knowledge further, maybe even leading to a career in science.”
Tactile Collider has its origins in a previous exhibit about the Higgs boson called Collider. When Collider arrived at the Museum of Science and Industry in Manchester, Marieke Navin, then the director of the Manchester Science Festival, was approached by a visually impaired woman and her husband. They were looking for ways to augment her experience of the exhibit.
Navin called University of Manchester and Cockcroft Institute physicist Rob Appleby, who brought 3D-printed accelerating cavities and detector pieces, along with a real metallic accelerating cavity. Navin and Appleby then walked the couple through Collider, answering questions and using the objects as guides. She says the pair were thrilled.
Artwork by Sandbox Studio, Chicago with Ana Kova
“Collider wasn’t very hands-on. Everything was behind cases,” Navin says. “They enjoyed holding the objects, but really the key thing was having that conversation with the scientist. So after they left, Rob and I said, ‘We’re on to something here.’”
Along with Edmonds, they received a £90,000 grant from Research Councils UK and spent over a year preparing the new methods and materials. Because none of the three is visually impaired, they spoke with consultants trained on the use of tactile maps and visited museums with blind people to get a sense of their experiences with exhibits.
They also enlisted the help of Robyn Watson, a qualified teacher of the visually impaired. Watson and her students communicated some of the challenges of teaching the visually impaired. What does it mean, for example, to tell a blind student that an elephant is big?
“It was a great opportunity for my children to be involved in something that was for them,” Watson says. “They could take ownership of the ideas and help to shape something that would hopefully inspire other students to grow and develop a subject that can be really difficult for all students to access.”
The final result is Tactile Collider, a 90-minute accelerator and particle physics experience that revolves around a 3.5-meter (11.4-foot) model accelerator named CASSIE (which stands for Conceptual Accelerator Supporting Scientific Inclusive Education). CASSIE links tables that contain various objects students can touch, interact with and listen to. With headphones, students can listen to audio featuring sounds generated from real data collected at the LHC.
“It sounded like it was a different planet almost, it sounded alien,” says 10-year-old Grace, who visited the exhibit.
Another student, 14-year-old Sean-Paul, says he enjoyed the exhibit’s magnets. “The North poles have spiky bits and the South poles are dented in so you could tell the difference,” he says.
Both students say they were fascinated with the way the scientists conveyed just how small fundamental particles are. They’d ask the students to handle a large ball and move stepwise down in size to a marble, a grain of sand and a piece of dust, an exercise that Sean-Paul’s teacher, Peter Marsh, noted could be helpful to anyone, visually impaired or not.
“It gave a tactile idea of scale with something you couldn’t touch,” Marsh says. “And that was useful because you can’t see that, even with the best vision, and you can’t feel that, even with the best sense of touch.”
At each station, students engage with a scientist who explains the meaning of the objects, which convey four central ideas in particle physics: that everything is made of particles, how magnets are used to steer and focus beams, how particles are accelerated around a ring, and how scientists discovered the Higgs boson.
For Grace and her sister, 12-year-old Ella, the opportunity to interact with scientists was a highlight of the Tactile Collider experience. Ella, who likes chemistry and wants to be a nurse, has limited vision, while Grace, a physics enthusiast who plans to be a scientist, has no sight. Neither had ever met a scientist other than their science teachers.
“I enjoyed talking to the scientists,” Grace says. “I was asking them loads of questions at the end, and we had a great big discussion about dark matter.”
Ella adds, “The scientists explained things clearly. It was good.”
“It’s a huge number,” Appleby says. “A lot of traditional ways of science engagement don’t take account of this at all.”
The difficulty visually impaired people face in accessing physics creates a paradox for Tactile Collider. While extending physics outreach to a traditionally underserved population, “it’s really highlighted the fact that physics isn’t that accessible to visually impaired people as a career choice,” Navin says. “Say we visit all these visually impaired children and we inspire someone, and they say, ‘I want to study physics.’ Is that going to be possible?
“By training scientists and raising awareness of underrepresented audiences within the scientific community we will be tackling this head on. The staff and students working with us to deliver Tactile Collider are the lecturers of tomorrow.”
In addition to touring around schools for the visually impaired, the group also plan to bring the exhibit this summer to events for the general public, such as music festivals. They have a long-term goal to create a framework for teaching physics to the visually impaired in the hopes of sharing what they’ve learned throughout the community.
“I’ve liked science for a long time because there’s so much to do,” Sean-Paul says. “With Tactile Collider, more people get to see what it’s like. Other people can know what it’s like. It’s not just for visually impaired people.”
National Society of Black Physicists President Renée Horton talks with Symmetry about finding a place to belong in physics.
Recognized as gifted but frustrated by a hearing condition she did not yet understand, Renée Horton dropped out of college at age 18. When she returned a decade later, she was raising three kids on her own.
A chance encounter with the National Society of Black Physicists gave Horton a new vision for her future. She went on to become the first African American to earn her PhD in material science—with a focus in physics—at the University of Alabama. Then she landed a job at NASA.
About two years ago, members of NSBP approached Horton to help them reinvigorate the organization that had provided her guiding star. Now, at the end of her two-year term as NSPB president, she discusses her experiences with Symmetry.
How did you get interested in science?
I was always very aware of the stars and the sky, and was always interested in science, even in elementary school.
But it wasn’t until I got to middle school and my science teacher—my 8th grade science teacher, Mr. Merrill, was very different. He was, like, a 6-foot-6 biker dude who actually came to school in black riding boots. He rode a Harley. And he had a leather jacket. And he had a beard like ZZ Top.
What that said to me right then was, even though I really didn’t know any Blacks in science, you really didn’t have to look like the typical Einstein to be a scientist. He was an amazing science teacher, and I think, for me, that’s when my love really kicked off.
I was in awe of the stars when I got my first telescope—you know, just being able to look beyond Earth. And then he just kind of sealed the deal for me, I guess.
When did you get your first telescope?
I got my first telescope on Christmas, and I had to be maybe 8 or 9. We [my brother and I] used to scale the antenna on the side of the house and put the telescope on top of the roof. And then we’d sit on the roof and look up at the stars and pray that when we got down we didn’t break anything.
I guess you didn’t break anything?
Um, actually, I broke my arm once. We didn’t tell my parents we were on the roof, per se. But I think they may have known. It still didn’t stop me from scaling the antenna.
How did you wind up in physics?
I’m a nontraditional student. So I started school the first time, didn’t get through, got pregnant, got married, followed my husband’s career, and then went back to school as a single parent. And then I actually went into engineering.
I got sent to a physics conference as a chaperone. It was the National Association of Black Physicists conference in 2003, and I was blown away. I was blown away at the research that the other students were doing. I was blown away that I was standing in a room of extremely smart Black people talking about things that were so beyond, you know, the universe, and I wanted that.
Was that your first science conference?
It wasn’t my first science conference. I had gone to NSBE, the National Society of Black Engineers, and I had gone to IEEE [the Institute of Electrical and Electronics Engineers].
But I never felt quite like engineering was it for me, because even when I was going to undergrad, the professor was like, “You need to go to grad school,” because I kept asking, “Well, why? Why are we doing this like this? And why are we doing this? And what happens if you do this differently?”
And the professor was like, “Yeah, you need to go to grad school. That’s where they answer those questions at. We don’t answer those questions here.”
And it was while I was in grad school for engineering that one of the professors—I wasn’t doing so well in his class, and he said, “You’re probably one of the dumbest students I’ve ever met. Are you sure you want to be doing a graduate degree?”
I was having a lot of difficulty understanding him because I’m hearing-impaired, and he spoke English as a second language. And I wasn’t understanding a lot of the words that he was saying. And even though I had a note-taker, the note-taker was also having trouble understanding him. So I never really could get complete notes to be able to truly understand what he was teaching, and I just didn’t fare well at all in his class.
But I was pretty certain I wasn’t dumb—because I could do physics, right? [She had taken a couple of lower-level classes.] And so I was like, I’m almost certain I’m not dumb. This just isn’t for me. Or this teacher just isn’t for me.
It was all that year that I was introduced to physics and was just in awe and gravitated toward it and wound up switching universities, switching concentrations from engineering to physics. I was just blown away with quantum. And math, I love math, and so when I got to do the math physics course, I was just like, yes, this is where I belong.
Were other people telling you that you didn’t belong?
I had a professor actually tell me that women should be at home raising the children. They shouldn’t be trying to get advanced degrees.
I was a single parent, too, so I was like, oh well, we rollin’ together, me and the kids. I’m going to get this degree one way or the other.
The sad part about it is, even being a nontraditional student and graduating now almost seven years ago, I’m still running into students that are feeling like they’re being second-guessed.
So that’s what I’m constantly talking about when I’m traveling now. What I’m constantly telling these students when I’m talking to them now is that you do belong here. You really have earned your seat at the table. Don’t let other people tell you you haven’t, because you have. You have a right to be here.
How did your hearing loss affect your studies?
When I went back to school the second time, I was more accepting of my hearing loss than I was before. I went back and it was like, you know what? This is who I am, and I’m going to accept it, and I’m going to learn to deal with it.
I did the nerdy thing, too. I started studying my hearing loss. I started trying to figure out what my hearing loss was, what was the best way for me to learn, what accommodations I needed.
And I was also more accepting of accommodations. Before I felt like accommodations were a show of weakness. When I went back to school it was like, yo, I want these accommodations—because I want to be amazing. I want to apply all my brainpower.
I had a note-taker. Him and I ended up being best friends. Because we had to take classes together. So after that first semester, all of our classes were together. He was an electrical engineering major as well—with a minor in math. I convinced him he needed to do a minor in math because I needed the note-taker. And then he went back and got a Latin degree. And we’re best friends still to this day.
I did all the coursework, but I did not pass the qualifier for the master’s program to get my thesis. I ended up leaving and enrolling in the PhD program. A professor actually recruited me and was like, “You don’t have to have a master’s.” I was like, “What? Yes, you do.” And he was like, “No, I don’t have a master’s. You don’t have to have a master’s. Nobody really cares if you have a master’s.”
And then I changed schools and went to University of Alabama and enrolled in the materials science program with a physics concentration. So all of my degrees actually came in my second time around, as a mom with three kids.
It’s a very interesting dynamic to have kids when you’re in school. The two were older, and when I went back to undergrad, my daughter was 2 at the time. So it was just a lot of preparation, a lot of planning that we had to do. We had a calendar on the wall, and if whatever the activity was didn’t make the calendar by Sunday, we didn’t do it. And I was very strict with that and held to that.
What do you do now?
I’m a materials physicist, so I am currently overseeing the metals and the welds on our space launch system, which is the new rocket that NASA is building that’ll eventually take us to Mars.
It’s an amazing thing to me because I look at parts and pieces sometimes and then I watch these guys integrate it together and, sooner or later, this year or the beginning of next year, we’ll have a whole rocket based off of the parts and pieces that I actually saw.
Mars is set for 2030, but we have some other missions that are coming before that. We have a mission in 2019 and then another one in 2020 or 2021. This is a new rocket system, so we really have to test it out way before we ever put humans on it.
When did you join the National Society for Black Physicists?
I didn’t join until 2004. In 2005 I represented the National Society for Black Physicists at the IUPAP [International Union of Pure and Applied Physics] Women’s Conference in Brazil, and everything just kind of took off from there.
I came back and created a women’s group for NSBP. I stayed a part of the organization up until about 2010, when I had a disagreement with one of the physicists [in leadership] and dropped out. I didn’t have anything else to do with the organization until they called and said, “We need you to run for president.”
Why did they need you to run for president?
They knew my work ethic and my attitude. I had worked with the organization before and had done some great things with the women’s group.
I’m very proud to say that we were able to help with restructuring debt that the organization had. We were able to rebuild membership with the organization, as well as reigniting that interest in the organization and getting more people to actually work with us and contribute financially.
How big is the organization?
The organization is about 385 members, with about 80 percent being students.
There are some unique benefits that come with being a member of NSBP. A lot of times we get organizations that are particularly looking to diversify their workforce, or have special programs for diverse students, and so they come to our organization.
Being a member also gives you direct access to mentors that have been through what you’re going through. It gives you access to the famous African American physicists—because most of them show up at the conference.
Our membership is not just African Americans, it’s anybody that wants to support African Americans as well.
What have your goals been during your time as president?
I always felt that there were so many people and so many programs trying to help African American physicists or Black physicists, but none of them were asking us how we needed to be helped. They were kind of deciding, you know, “We should do this program,” and then we were getting invited afterwards.
And one of the things we went into our tenure saying was that if you weren’t inviting us to the table when the planning was happening, we weren’t interested in being at the table.
What is something that people were missing?
One of the things is that they want to think that it’s enough to give a student a mentor, and they were neglecting how important it is for a student to see, know and interact with people who look like them. That’s really important. There’s a whole lot of research on that.
At NSBP we give you that. You can walk in a room and you can find somebody who looks like you, whether you’re male or female, but you can also find somebody who is as nerdy as you, you can find somebody who is as eclectic as you, you can find somebody who’s as straight and narrow as you. You really can.
To be in a place where you can find somebody that you can find a connection with, that’s what you need sometimes. We would always say that the conference was the way that we refilled our cup, to be able to endure what it was like being the only—or being the first—or being one of two.
You know, a lot of us are walking around with that feeling that, if I mess up, I’m going to close a door for the next Black that’s coming behind me. So that’s quite a big burden. But when they’re with us at the conference or with us in our environment, they don’t have to feel like that. So it’s a relief for them, even if it’s just a weekend. But it’s also just a way to refill that cup for them to keep going.
DUNE, a global project hosted by the US Department of Energy’s Fermi National Accelerator Laboratory, will send the world’s most intense high-energy beam of neutrinos 800 miles from Illinois to the world’s most advanced, mile-deep neutrino detectors in South Dakota. The goal? To study how the neutrinos change—oscillating from one type to another—to better understand how the mysterious particles might have influenced the evolution of our universe.
The experiment has more than 1000 researchers on board from 31 countries, a collaboration that scientists expect to continue to grow. Rout, a theoretical physicist originally from Odisha, India, received the second-ever Rajendran Raja Fellowship aimed at bringing students from India to conduct research at Fermilab.
What do you work on for LNBF?
My work is on the theory of high-energy physics. I predict what will happen to neutrinos in the beam made here at Fermilab as they travel, calculating how they oscillate. I also look at neutrino and antineutrino asymmetry, called CP violation, in both standard interactions and new physics scenarios that go beyond what we currently know about neutrinos.
Before this fellowship, had you ever been to Fermilab?
This is my first time. It’s actually my first time going anywhere outside India. Physics students in India have a dream to come to places like Fermilab or CERN. I’m just excited to be here. I’m like a tourist and want to learn about all the experiments here.
When did you find out that you liked physics?
I remember being interested in math and science from a young age. I was actually the first student to go on to study science in my hometown. In my family, I’m the first person to get a PhD.
I always liked physics and performed well in it, but I come from a very rural area, and even my college was in a rural area. I knew of very few science-related careers.
I had a good teacher and mentor during my bachelor’s degree who guided me, and I discovered my interest around this time. When other students were going on to get jobs, this teacher encouraged me to further my education in physics and get my master’s degree at a university in the city.
What challenges have you faced while getting your PhD?
While getting my bachelor’s, master’s and PhD, which I am in my final year of, there have been ups and downs. Getting a PhD is a difficult path in some respects. Financially it can be difficult. One needs commitment to developing their abilities. At times I felt I was not performing up to expectations. I just remembered that I shouldn’t give up because it takes perseverance and hard work.
My brother, Mr. Manguli Rout, has always been there for me as moral support and encouraged me. I’ve been lucky to have teachers to support and guide me, too. My own perseverance and support from my friends and mentors has helped me accomplish what I have. I’ve transformed into a better and stronger person.
What first got you interested in studying neutrinos?
Before graduate school, my exposure to particle physics was very little. I still didn’t know about Fermilab or other institutions that research particle physics outside of India like CERN.
During my master’s at Utkal University, I was taught a course on high-energy physics by very good teachers, Prof. Swapna Mahapatra and Prof. Karmadeva Maharana. They inspired me to take up research in the field of high-energy physics.
After I was selected to receive my PhD at Jawaharlal Nehru University in 2013, I carried out a semester-long research project on neutrino oscillations, doing analytic and numerical computations with Dr. Poonam Mehta. This piqued my interest in neutrino physics, so I joined Dr. Poonam Mehta for my PhD program.
What do you like about studying neutrinos?
I’ve been interested in high-energy physics since my master’s degree, and I’ve always really liked mathematics. My current university has a focus in neutrino theory and high-energy physics. The study of neutrino oscillations is sort of a combination of mathematics and high-energy physics, and since I like both of these, I chose this as my specialty.
Neutrinos are fascinating because they are tiny neutral particles with peculiar properties, produced by a wide variety of sources—solar, atmospheric, reactors and accelerators and more, all with different energies. They’re omnipresent and millions pass through us yet cause no harm. Neutrino physics connects various branches of physics—particle physics, astrophysics and cosmology—making it a more comprehensive study for theory.
What do you hope to discover about neutrinos while working on LBNF?
Some questions in neutrino oscillation physics remain unanswered. We know there are three flavors, electron, muon and tau, which have different energies and display particular behaviors.
Since I’m a theorist, I predict how they will oscillate when they pass through matter. The more precise my calculations are, the more accurately we can make a certain flavor of neutrino for experimental physicists to study. They’ll gather information on the neutrino’s characteristics to solve unknowns like CP violation and mass ordering of the neutrino mass states, which combine to form the neutrino flavors.
One mystery surrounding neutrinos is CP violation. This is where there are different numbers of antineutrinos than neutrinos or they behave differently. We want to study this and hope to solve the mystery of why it occurs. In the process, we could also end up accounting for other unknowns that can reveal more about how the universe works.
What do you hope to accomplish during your fellowship?
I want to learn techniques for making the best possible predictions before DUNE begins. The results of the experiment will be more accurate if I calculate exactly right. These calculations help us better engineer and construct LBNF and overall to understand neutrinos better.
Has anything surprised you about Fermilab?
If you are coming from one line of work, it’s surprising how people work within different departments. For example, theoretical people work independently and often work alone but need to be very precise because everyone else’s work depends on them.
Experimental departments work together and collaborate more. I’ve also been surprised by how fast we move with the calculations. I’ve become faster since working here, which is a good skill to have.
I’m especially surprised by how open everyone has been here. They answer all my questions, are always helpful and inspire me to come up with new ideas.
What is an average day like for you?
My work is split between Fermilab and JNU. At Fermilab, my supervisor is Dr. Laura Fields. At JNU, my PhD advisor is Dr. Poonam Mehta, and we are currently collaborating with Dr. Mary Bishai at Brookhaven National Laboratory, Dr. Mehedi Masud who is a post-doctoral fellow at IFIC-AHEP, Valencia, and two PhD students in our research group on different projects.
This means that while I do many calculations for LBNF work here at Fermilab, I also have a lot of phone calls and Skype meetings with collaborators at my university, which can be at odd times since they are in such different time zones.
Do you work with other international students or students from your university?
There are other Indian students working at Fermilab, but none from my university. I do have a friend here who I met in my master’s degree program. He actually works on NOvA [another neutrino experiment at Fermilab] while I am working on LBNF/DUNE. He’s very supportive of me and my studies and research.
What do you like about working on an international collaboration?
The best part is that you can easily approach anyone in the collaboration and there is so much expertise available. You get ideas from so many different people, and they are all eager to help you learn more and are open to hearing your ideas, too.
I really like the exchange of ideas between such diverse scientists and getting a good platform and facility to do research in. It’s quite competitive, so once you get it, you need to give it your 100 percent to make it a success. Overall, it’s surprising to me how huge the project is and how many experts in the field are working on it.
What have you learned so far?
My computational abilities have really improved. I’m beginning to compute results so I can compare them to actual experimental results later.
I’ve been thinking about the experimental side more than usual to see how theory translates into the experiment. My research is indirectly helping the experiment by ensuring the particles behave exactly how the experimenters want them to.
And I’ve learned how to collaborate and bounce ideas off of other people. The work culture is so diverse around campus. I’m learning to understand the requirements of different work environments and to communicate with all different kinds of people.
When they look for violations of Einstein’s general relativity, physicists deliberately plan experiments to find nothing at all.
In 1887, physicists Albert Michelson and Edward Morley performed one of physics’ most famous experiments (at Case Western Reserve University, coincidentally, across the street from where this article was written). Unlike other important experiments, they didn’t find what they were looking for, but unexpectedly their “null” result prepared the way for the theory of relativity.
Sometimes researchers deliberately set out to generate null results—while on the lookout for something new. One type of experiment is looking for deviations from Einstein’s general theory of relativity.
“General relativity has been the staple of gravitational understanding for 100 years,” says Katie Chamberlain, a physics student at Montana State University. “We have to rule out the potential for other existing theories to come in and replace [it].”
Many alternative theories of gravity are out there, designed to explain various phenomena or fix general relativity’s famous incompatibility with quantum theory. Some of these predict differences in the behavior of gravity that can be tested in the lab.
One experiment examined precision measurements of the distance between Earth and the moon. Another recent test involved superconducting gravimeters, which measure how strong gravity is in various places on Earth’s surface. If there are gravitational effects not described by general relativity, they might show up in those experiments: the highly coveted results known as “new physics.”
The null result tells us where new physics is not. That limits the places that one can continue to look for new physics.
In these cases, everything was perfectly in line with general relativity, but that doesn’t mean the experiments were failures.
“It isn’t especially a disappointment,” says Jay Tasson of Carleton College, who worked on the superconducting gravimeter analysis. “The null result tells us where new physics is not. That limits the places that one can continue to look for new physics.”
In other words, even an experiment in line with general relativity tells us something, in this case that any theory—including theories not yet born—with results at odds with these results (as long as they hold up) must be wrong.
“Progress in this field is often measured by [looking] with better sensitivity than anyone has looked before,” Tasson says
Einstein’s happiest thought
Though general relativity is mathematically complicated, it’s based on some simple concepts. Among those: Objects experiencing only gravity don’t feel any force acting on them. That’s how someone aboard the International Space Station can float as freely as if there were no gravity at all, even though the force of gravity at that orbit is only about 10 percent less than it is on the surface of Earth. Einstein called this realization “the happiest thought” of his life.
A consequence of this happy thought is “local Lorentz invariance.” “Local” means “approximately at a single point in space,” and “invariance” means two experiments performed under equivalent conditions should return the same results. “Local Lorentz invariance” means (for example) two experiments at the same position should be the same if one is rotated by 90 degrees compared with the other. While real experiments take up more than a single point in space, researchers compensate for that through precision measurements and understanding how the size of their experiment affects results.
Several theories of gravity predict violations of local Lorentz invariance, including string theory and other quantum theories of gravity. Most of these violations occur at smaller length scales than current experiments can reach, but some effects might “leak” into testable regimes.
Rather than test a particular alternative theory, gravitational physicists worked out a general framework for modeling deviations. The framework consists of numbers that are all zero in general relativity but take on various values depending on which alternative theory is doing the predicting.
“Currently there are a lot of constraints on different modified theories of gravity,” Chamberlain says. “As we’re able to explore more relativistic spacetimes with higher sensitivities from our instruments, we’ll be able to place much tighter constraints.”
Astronauts starting with Apollo 11 left “retroreflectors” on the surface of the moon that reflect light directly back toward the source. Astronomers on Earth send laser beams through telescopes at those retroreflectors and time how long it takes the light to come back to the observatory. These “lunar-ranging” experiments are some of the best tests of general relativity we have.
“The usefulness of the lunar laser ranging experiment is mainly due to its very precise data,” says Adrien Bourgoin of the University of Bologna. He points out that these experiments are precise on the level of centimeters, compared with the 400,000 kilometer distance between Earth and the moon. That’s good enough to see possible deviations from general relativity.
For example, if gravity violates local Lorentz invariance, it might affect the travel time of light differently when the moon is aligned with the sun (full and new moon) than when the moon and sun are at right-angles with respect to Earth (half-moon). That’s a large-scale version of rotating the experimental apparatus.
The first lunar distance test began in 1969, with many follow-up experiments. Bourgoin and his colleagues looked at 13 tests involving five different observatories.
The lunar retroreflectors were intended to test relativity, but the Earth-bound superconducting gravimeters that Jay Tasson and his colleagues used in their relativity tests are primarily there to study variations in our planet’s gravity due to rock density, earthquakes, the moon’s pull, and so forth. These instruments consist of metal spheres cooled until they become superconducting, which means they can be levitated using electromagnets. By keeping them levitating at precisely the same height, the instruments can measure the gravitational field at that position.
As with lunar ranging, these gravimeters provide a lot of precise data, some going back over a decade. Tasson and his collaborators compared results between multiple groupings of gravimeters around the world to look for any variations that can’t be explained by ordinary phenomena.
Both sets of researchers concluded there are no violations of general relativity that can be detected at this level of precision. In both cases, though, these data are improvements over what came before, with the lunar-range experiment showing as much as a thousandfold increase in precision over prior measurements.
“Any set of experiments that you can do to test general relativity are going to be complementary to each other,” Chamberlain says.
In particular, her research looks at how future gravitational-wave observatories might spot deviations from general relativity—including Lorentz invariance violations. Unlike the Earth and moon tests, these gravitational waves come from the strongest gravity we know: colliding black holes and neutron stars.
“We need very strong signals to be able to tell the difference between a Lorentz-violating gravitational-wave form and a gravitational-wave form that looks like it should in general relativity.”
In the meantime, nobody is terribly surprised to see experiments perfectly in line with Einstein’s theory.
“I’m pleased that the measurements are null,” Bourgoin says. “If not, I’ll still be working on the subject wondering if the measurements come from computational errors or if it is real.”
He recalls the experiment from 2011 that deceptively appeared to show neutrinos traveling faster than the speed of light, a result that vanished under later analysis. A seeming violation of local Lorentz invariance would also likely mean measurement snafus rather than a fundamental discovery.
But there’s always that chance. And, like the Michelson-Morley experiment, the “nothing” results tell us where new physics may or may not be hiding.
Fermilab’s 2017 artist-in-residence, Jim Jenkins, melds pieces of physics experiments into his creations.
When founding director Robert R. Wilson first imagined Fermilab in the 1960s, he not only envisioned a lab that was at the forefront of physics, but a space that would inspire visitors and elicit an appreciation of the research. From the beginning, he recognized the importance of fusing art and science.
Today Fermilab continues this legacy through its Artist-in-Residence Program. The 2017 artist-in-residence, Jim Jenkins, has created sculpture and mixed media meant to capture the magic of complex experimental equipment and intangible particles.
To create the pieces for his Fermilab Art Gallery show, A Perplexity of Conundrums, he pulled mechanical parts right out of particle detectors and accelerators, incorporating them into intricate works of art. Their careful assembly reflects the same attention to detail required to make the technology involved in particle physics research.
“The Tevatron [Fermilab’s retired particle collider] has 500,000 parts, and they all had to work perfectly, in unison, to be able to do what it did. That is a staggering number,” Jenkins says.
Jenkins uses leftover materials or pieces from out-of-date equipment, giving them new life. These include a piece of copper buss (a bar used to ground or conduct electricity) from the Tevatron, a mirror once used for measuring the energy of particles, detector film and wire, and other odds and ends.
He carefully arranges these relics of experiments past amongst other curiosities, including a Canadian beaver pelt, bass strings, X-ray images, owl talons, a duck-handled umbrella, and even a copy of a page from Enrico Fermi’s calculations.
Each piece is multifaceted with several, often contradictory, possible interpretations.
“Watching other people view this exhibit has been such a pleasure, because I’ve never seen people take so much time with art before,” says Georgia Schwender, the curator of Fermilab’s gallery.
Jenkins’ sculpture titled A Close Shave incorporates a spare part from the Tevatron called a beam trimmer.
Photo by Reidar Hahn, Fermilab
Jenkins’ Ring around the Ring sculpture originally functioned as a snowflake detector inspired by Fermilab’s particle detectors and is now on display in the gallery.
Photo by Reidar Hahn, Fermilab
In Jenkins’ sculpture called The Failure of the Material, he uses a magnifying class to emphasize an owl talon.
Photo by Reidar Hahn, Fermilab
At the artist’s reception for Jenkins’ show, a visitor peers through the magnifying glass of a sculpture called The Wait of the World.
Photo by Reidar Hahn, Fermilab
A visitor closely examines Beauty & Boredom at the artist’s reception of the gallery opening.
Photo by Reidar Hahn, Fermilab
In the foreground is a duck head handle of an umbrella used in Sitting Duck Soup. Behind it is a Geiger Counter that measures the melting water from the umbrella.
Jenkins, who also exhibited at Fermilab in 2005, says he has become less inhibited in his art over time. In his 2017 show, he boldly symbolizes the danger of unsustainable human activity. He evokes mortality with bones and X-rays. He represents the fragility of the Earth with melting pyramids of ice and damaged mechanical parts.
Many of his sculptures demonstrate the laws of physics in motion. They rhythmically drip water, sustain living fish, rotate through magnetic attraction, or use a Geiger counter to measure particle decay. Their energy embodies scientific research at Fermilab: an active endeavor.
In his piece Ring Around the Ring, Jenkins assembled a unique snowflake-detector system using wires from the Tevatron, a sensitive microphone, and a recorder, along with X-ray film on which to record the sounds of the ephemeral crystals. The sound of a snowflake landing on a wire is as subtle as the miniature burst of light a neutrino creates in a neutrino detector, Jenkins says. He hopes this parallel will help his audience grasp the nature of the ghostlike particle.
As Schwender says, “His art opens a door for people that don’t usually think about physics. Not everybody can sit down and look at a textbook and find joy or curiosity, and this is an alternative approach.”
For Jenkins, the research at Fermilab has always been part of his vision for his art. “In 1992 I made a bucket list of things I wanted to do and number 13 was, ‘I want to work at Fermilab and make art there.’”
A Perplexity of Conundrums opened January 8 and will run in the Fermilab Art Gallery until March 6. It is open to the public from 8 a.m. until 4:30 p.m. Monday through Friday. Jenkins will also be giving a Gallery Talk that is open to the public on Feb. 26 at noon in the Fermilab Art Gallery.
Are these mass-giving particles hanging out with dark matter?
The Higgs boson has existed since the earliest moments of our universe. Its directionless field permeates all of space and entices transient particles to slow down and burgeon with mass. Without the Higgs field, there could be no stable structures; the universe would be cold, dark and lifeless.
Many scientists are hoping that the Higgs boson will help them understand phenomena not predicted by the Standard Model, physicists’ field guide to the subatomic world. While the Standard Model is an ace at predicting the the properties of all known subatomic particles, it falls short on things like gravity, the accelerating expansion of the universe, the supernatural speeds of spinning galaxies, the absurd excess of matter over antimatter, and beyond.
“We can use the Higgs boson as a tool to look for new physics that might not readily interact with our standard set of particles,” says Darin Acosta, a physicist at the University of Florida.
In particular, there’s hope that the Higgs boson might interact with dark matter, thought to be a widespread but never directly detected kind of matter that outnumbers regular matter five to one. This theoretical massive particle makes itself known through its gravitational attraction. Physicists see its fingerprint all over the cosmos in the rotational speed of galaxies, the movements of galaxy clusters and the bending of distant light. Even though dark matter appears to be everywhere, scientists have yet to find a tool that can bridge the light and dark sectors.
If the Higgs field is the only vendor of mass in the cosmos, then dark matter must be a client. This means that the Higgs boson, the spokesparticle of the Higgs field, must have some relationship with dark matter particles.
“It could be that dark matter aids in the production of Higgs bosons, or that Higgs bosons can transform into dark matter particles as they decay,” Acosta says. “It’s simple on paper, but the challenge is finding evidence of it happening, especially when so many parts of the equation are completely invisible.”
The particle that wasn’t there
To find evidence of the Higgs boson flirting with dark matter, scientists must learn how to see the invisible. Scientists never see the Higgs boson directly; in fact, they discovered the Higgs boson by tracing the particles it produces as it decays. Now, they want to precisely measure how frequently the Higgs boson transforms into different types of particles. It’s not easy.
“All we can see with our detector is the last step of the decay, which we call the final state,” says Will Buttinger, a CERN research fellow. “In many cases, the Higgs is not the parent of the particles we see in the final state, but the grandparent.”
The Standard Model not only predicts all the different possible decays of Higgs bosons, but how favorable each decay is. For instance, it predicts that about 60 percent of Higgs bosons will transform into a pair of bottom quarks, whereas only 0.2 percent will transform into a pair of photons. If the experimental results show Higgs bosons decaying into certain particles more or less often than predicted, it could mean that a few Higgs bosons are sneaking off and transforming into dark matter.
Of course, these kinds of precision measurements cannot tell scientists if the Higgs is evolving into dark matter as part of its decay path—only that it is behaving strangely. To catch the Higgs in the act, scientists need irrefutable evidence of the Higgs schmoozing with dark matter.
“How do we see invisible things?” asks Buttinger. “By the influence it has on what we can see.”
For example, humans cannot see the wind, but we can look outside our windows and immediately know if it’s windy based whether or not trees are swaying. Scientists can look for dark matter particles in a similar way.
“For every action, there is an equal and opposite reaction,” Buttinger says. “If we see particles shooting off in one direction, we know that there must be something shooting off in the other direction.”
If a Higgs boson transforms into a visible particle paired with a dark matter particle, the solitary tracks of the visible particles will have an odd and inexplicable trajectory—an indication that, perhaps, a dark matter particle is escaping.
The Higgs boson is the newest tool scientists have to explore the uncharted terrain within and beyond the Standard Model. The continued research at the LHC and its future upgrades will enable scientists to characterize this reticent particle and learn its close-held secrets.
When it comes to love, sometimes you have to say it with science.
Valentine’s Day is upon us. If you’re still trying to find the right words to tell the loved ones in your life how you feel, look no further. The staff of symmetry has assembled another round of valentines so you can let the universal language of physics do the talking. (And if you need more options, you can check out our previous valentines here.)
Love is a mysterious force, and so is dark energy. Tell your valentine how they broaden your horizons:
Artwork by Sandbox Studio, Chicago with Ana Kova
Show the depths of your unity with this card. Einstein would approve!
When it comes to talent, versatility and the power to change the world, which atomic particle is the champ? Read what our four contenders have to say — then you decide.
Physics fans, are you ready to rumble?
Of course you are — and you’ve come to the right place. In the text that follows, you will have a ringside seat to perhaps the most anticipated skirmish in science history, as four atomic adversaries duke it out for the coveted title of Most Awesome Subatomic Particle of the Millennium.
More rousing than the Rumble in the Jungle, more chilling than the Thrilla in Manila, we present to you, ladies and gentlemen, the (drumroll, please) Subatomic Smackdown.
There will be no messy blood, sweat or other bodily fluids involved in this brainy battle. This is a war of words, ideas and wit based in science, from which one, and only one, of these four deserving combatants will emerge as victor. Introducing:
In the blue corner, championed by CERN (the European Organization for Nuclear Research) near Geneva, Switzerland, and weighing in at 938.27231 megaelectronvolts (MeV), is the proton.
In the red corner, supported by SLAC National Accelerator Laboratory in Menlo Park, California, USA, and weighing in at—well, nothing, really—is the photon.
In the purple corner, championed by the National High Magnetic Field Laboratory in Tallahassee, Florida, USA, and weighing in at 0.51099906 MeV, is the electron.
Finally, in the green corner, rooted on by the Institute for Quantum Matter at Johns Hopkins University in Baltimore, Maryland, USA, and weighing in at 939.56563 MeV, is the neutron.
This epic physics feud will take place over four rounds, as each challenger (with a little help from their supporters) will argue why it, and it alone, deserves to hold the title of Most Awesome Subatomic Particle.
So … electronvolt for electronvolt, which particle packs the most impressive punch? Read on, award points as you go, then weigh in on who you believe emerges as champion of this quantum quarrel.
Pay heed to this smashing subatomic celebrity, used in medicine and to produce neutrinos, antiprotons and, of course, the God particle.
Step aside, lightweights. The proton has arrived. And I’m positive that I’m the very best.
You may have heard of me. Ever seen a model of an atom? Right there in the middle of everything: protons.
Weight: 938.27231 MeV
Year discovered: 1911
Yes, there are also neutrons in the nucleus. But they’re lucky just to be there, aren’t they? Look up any element's atomic number and you'll see which particles really count for something. Protons are the best, and scientists know it. After all, my name comes from the Greek word for “first.” Electrons? They’re fighting just to be in our orbit.
What else? Those hadronsin the Large Hadron Collider (LHC) at CERN? Protons, of course.
I don’t like to brag, but do you know about the Higgs boson? The “God particle”? The last undiscovered piece in the Standard Model of particle physics, the one scientists spent five decades trying to find? Do you know who finally discovered that particle?
Protons did. When LHC scientists crashed us together, we made so many of those bosons that scientists couldn’t help but see them. There’s a reason they built a 17-mile accelerator — spanning two countries! — just for us.
The takeaway here? Protons make an impact.
So maybe I don’t zip around the LHC at exactly the speed of light. I do get pretty close, and besides who would want to? I am a particle of substance. I have mass.
Unlike you photons and electrons, I’m not just some simple, point-like particle. I have an inner self, full of quarks and gluons. The force that holds them all together? The strong nuclear force — which, by the way, is almost 140 times as strong as the electromagnetic force (sorry not sorry, electrons).
Unlike some of you, I can stand up for myself. Push me and I’ll push back, converting energy into brand new gluons and virtual particles. I’m not some clumsy electron, speeding around just as fast as you please.
What I am is creative — not to mention multitalented. Higgs bosons aren’t the only particles I can make. Need some neutrons? Some neutrinos? How about anti-protons or rare isotopes? Protons can make any of those: Just point us toward the right target.
You might think I’d get tired of being so amazing. You might think that, like some neutron, I’d eventually wear out, give up and come apart. But I am rock solid. As far as scientists know, I will never decay. And if I do, I’ll still probably last longer than every planet, star and galaxy around.
In sum, protons are collections of quarks and gluons, held together by the strong force, possibly for eternity. You can find them in everything built of atoms, and they’re key players in both medicine and basic research. In sum, protons are the best.
Lighter than a butterfly, faster than a bee (by far) — no other particle can compete with me!
Year discovered: 1923
I go 186,000 miles
a second,1 faster than you can go,
I’m massless,2 in fact:
your weight holds you back.
Got my attosecond attitude,3
while gravity’s got you subdued.
I’m everywhere, nowhere;4
there’s no place
you can go where
I can’t be —
I’m the original
of particle-wave duality.5
I am all colors,
You can’t hide from me.
From big to ultrasmall,
don’t you know I reveal it all?
I’ll show you what the deal is:
photosynthesis6 and double helix.
With X-rays you can see inside,
deflect off atoms while I glide.
I’m the heir apparent.
Fast-moving fire atom,8
transmitting your datum,9
bouncing through the
13 billion miles10
from Voyager’s eye,
See me in the sci-fi —
I destroyed Alderaan11
then in the real world
I grew the grass on your12
I come from the sun at
half a hellawatt;13
forget about it, your words
Your matter is trash,
time to scatter fast.
Written with the assistance of Karl Gumerlock, Amanda Solliday and Alan Fry
The speed of light is 299,792,458 meters (about 186,000 miles) per second. Nothing moves faster.
Theory and experiments agree that photons have energy and momentum, but no mass.
The fastest controlled laser pulses occur in just attoseconds, or billionths of a billionth of a second.
Cosmic microwave background radiation, a form of light from the Big Bang, permeates our universe.
Light seems to behave like a wave sometimes and a particle other times.
X-ray imaging experiments have provided important clues to how life works, from DNA to photosynthesis.
Light is coherent when its waves travel in fixed relationships. This is a property of lasers.
In ancient Hindu physics, light rays were made of fire atoms called tejas.
Examples of telecommunication that rely on photons: radiofrequency wireless signals, microwaves and fiber optics.
NASA uses light to communicate with space missions billion of miles away through huge radio antennas on Earth and in space.
In Star Wars, a laser from the Death Star destroys the peaceful planet.
Photons drive photosynthesis and the atmospheric warming that influences Earth’s weather and climate.
The solar energy output is about 0.4 x 1027 watts, an order of magnitude referred to unofficially as “hella.”
Round 3: The Electron
It might look like wizardry, but racking up a shelf of Nobel Prizes is all skill, ingenuity and inherent greatness.
It goes without saying that the electron is the greatest subatomic particle, but I’ll take the time to explain why to those confused individuals who would suggest otherwise. Although our greatness is 100 percent established by science, we do see how some might become so awestruck as to suspect that hocus-pocus is somehow involved.
Weight: 0.51099906 MeV
Symbol: e-, β-
Year discovered: 1897
First out of our bag of tricks: If you are reading this on a computer or cell phone screen, you are welcome. If you want to forward this to a friend or loved one — and I hope you do — feel free to use email. And what do you think the “e” stands for, anyway? Without me, you’d be swiping on a touchscreen or banging on a keyboard to do what? Generate neutrons, protons or photons? I don’t think so.
Oh sure, the internet uses photons to transmit information, but it gets the information from electrons and it converts the information back to electrons before it arrives at its destination.
And if you are sitting down, you are also welcome. Because without the electronic bond, you’d fall right through your chair to the floor … and then through the floor … and so on. All the way down — now there’s a disappearing act!
In fact, I’m so important to everyday life that I was the first elementary particle to be discovered by scientists, a feat performed by J.J. Thomson in 1897 for which he received the Nobel Prize. In 1911, we electrons paired up at low temperatures to perform our superconductivity dance for Heike Kamerlingh Onnes. We zipped so fast through that mercury: Now you see us, now you don’t! Another Nobel Prize. It took scientists 46 years to explain that dance, thanks to our deep understanding and clever use of quantum mechanics.
Then in 1986, in a very thin layer of copper and oxygen atoms, we performed our superconductivity dance at temperatures far exceeding anything previously known. We bagged more Nobel Prizes for that discovery (Hmmmm … that name seems to keep popping up like a rabbit out of a hat!). And even though engineers are already using high-temperature superconductivity in new magnets and other technologies, physicists still haven't discovered how we do it!
That’s the thing. We electrons are genius magicians, always coming up with new tricks to amaze. But we’re also genius entrepreneurs … always providing new technologies to benefit humanity. Your other subatomic particles neither amaze nor innovate, playing the vaudeville circuit while our name is in lights on Broadway.
These days, my greatest tricks occur when I get together with quadrillions of my fellow electrons and — presto chango! — invent new collective behaviors, or electronic correlations, as scientists call them. Think of birds flocking, fish swimming in schools or other beautiful and powerful group behaviors that you’d never see or appreciate if you only studied animals as individuals. Those abilities, combined with the fact that we electrons are completely indistinguishable from each other, means that we do amazing things that still baffle scientists.
In one recent acclaimed performance, we were traveling in a material so thin we were constrained to two dimensions. Then, when scientists put us in a high magnetic field, we electrons danced around in circles and got together with the magnetic flux quanta to create new particles that — abracadabra — had only one-third of the electric charge of an electron! To put that in terms you in the classical world might understand, that’s like using a giant pile of bricks to build a wee house the size of a third of a brick.
This fractional quantum Hall effect is one of our favorite tricks. It netted us electrons more Nobel prizes and rewrote the physics textbooks to focus on topology, which should sound familiar because it landed a Nobel in 2016 — are you sensing a trend here?
Alone as individuals, together in superconducting pairs or working in countless correlated confabulations, we electrons are the best magicians and the brightest inventors of all the subatomic particles. And that is no illusion. Electron out. Mic drop.
We’re neutral, not unbiased: Revealing science secrets as we scatter, neutrons are worth our weight in the gold we create.
There really can be no disputing the superior, indeed noble stature of the neutron. I make the ultimate sacrifice in the name of science (more on that in a bit) and am the undisputed heavyweight of the subatomic world. Massless, a photon clearly lacks gravitas, while the electron, I am sorry to say, is a complete lightweight. And despite the proton’s boasts of heft, I have outweighed it for 13.8 billion years.
Weight: 939.56563 MeV
Year discovered: 1932
You should thank your lucky neutron stars, dear reader, for our excess mass. If neutrons were lighter than protons, then we would be the stable particles, and protons could decay into us! Hydrogen would be unstable and unable to fuel the stars, which created the carbon within you. So if we didn’t outweigh protons, you would not even be here!
I overcame a rough start. Because neutrons can only survive about 15 minutes alone (after that, regrettably, we turn into an electron, a proton and a neutrino through radioactive beta decay), just one in seven of us survived the Big Bang, by sticking to protons and forming helium-4. Indeed, without neutrons, everything would be hydrogen, the only atom that can live without us.
We neutrons coexist even at the astronomical scale. Neutron stars are made up almost exclusively of us. Why should you care? Look no farther than your golden ring: We made it, and all heavy elements, in violent neutron star collisions.
Free of electric charge, we eluded scientists longer than photons, electrons and protons. The neutrons produced by bombarding beryllium with helium-4 were initially mistaken for photons. So sad! Refined experiments by James Chadwick in 1932, however, led him to recognize that he had discovered either the neutron or the violation of energy and momentum conservation. Needless to say, it was I!
Since then, our brilliance has grown by leaps and bounds. Thanks to fancy inventions like high flux fission reactors and the spallation neutron source at Oak Ridge National Laboratory, scientists can free us from our nuclear dwellings to form neutron beams, which help them see atoms dance and electrons spin. True: X-rays are handy for figuring out the atomic structure of materials. But neutrons find things that escape even them, including tiny hydrogen atoms, even those hiding among heavy atoms! Our penetrating power gives scientists “neutron vision” to see water in an operating fuel cell, oil in an operating engine, and problems in your smartphone battery that does not hold its charge.
When a beam of us hits our target, we scatter like bouncy balls to reveal in amazing detail the good vibrations (phonons) inside. And because we spin, we feel magnetism. So when a scientist puts a material inside a powerful magnetic field and aims a beam of us at it, we divulge its magnetic secrets. We can even create and annihilate those crazy emergent particles that electrons are always waxing poetic about.
So, there you have it: We are the secret nuclear ingredient to overcoming repulsive protons; we alone form heavenly bodies that create gold mines; and when we are liberated through fission or spallation, we offer scientists an unsurpassed view of mischievous electrons and of atoms large and small. But the view comes at a price: As we are detected, we suffer the indignity of turning into lowly protons and electrons! Consider the nobility of this final act as you lock in your vote for me, objectively the best subatomic particle (n0 contest).
We’re moving the final round out of the ring and into the social sphere. Which particles will go down for the count and which one will take the prize? You decide.
On March 30, follow the blow-by-blow on Twitter at #SubatomicSmackdown and join a corner to support your favorite particle. But remember: We want a good clean fight, so let’s keep those tweets above the belt, everyone.
Tally your points and submit your scorecard on Smackdown Day via our Twitter poll (@NationalMagLab). The champion will be selected by majority decision.