Category Archives: Quantum Physics

New research explores the imaginative possibility that our reality is only one half of a pair of interacting worlds.

Physicists sometimes come up with bizarre stories that sound like science fiction. Yet some turn out to be true, like how the curvature of space and time described by Einstein was eventually confirmed by astronomical measurements. Others linger on as mere possibilities or mathematical curiosities.

In a new paper in Physical Review Research, Joint Quantum Institute (JQI) Fellow Victor Galitski and JQI graduate student Alireza Parhizkar investigated the imaginative possibility that our reality is only one half of a pair of interacting worlds. Their mathematical model may offer a fresh perspective for looking at fundamental aspects of realityincluding why our universe expands the way it does and how that relates to the most minuscule lengths allowed in quantum mechanics. These topics are critical to understanding our universe and are part of one of the great mysteries of modern physics.

The pair of scientists stumbled upon this new perspective when they were looking into something quite different, research on sheets of graphenesingle atomic layers of carbon in a repeating hexagonal pattern. They realized that experiments on the electrical properties of stacked sheets of graphene produced results that resembled little universes and that the underlying phenomenon might generalize to other areas of physics. In stacks of graphene, new electrical behaviors arise from interactions between the individual sheets, so maybe unique physics could similarly emerge from interacting layers elsewhereperhaps in cosmological theories about the entire universe.

A curved and stretched sheet of graphene laying over another curved sheet creates a new pattern that impacts how electricity moves through the sheets. A new model suggests that similar physics might emerge if two adjacent universes are able to interact. Credit: Alireza Parhizkar, JQI

We think this is an exciting and ambitious idea, says Galitski, who is also a Chesapeake Chair Professor of Theoretical Physics in the Department of Physics. In a sense, its almost suspicious that it works so well by naturally predicting fundamental features of our universe such as inflation and the Higgs particle as we described in a follow up preprint.

Stacked graphenes exceptional electrical properties and possible connection to our reality having a twin comes from the special physics produced by patterns called moir patterns. Moir patterns form when two repeating patternsanything from the hexagons of atoms in graphene sheets to the grids of window screensoverlap and one of the layers is twisted, offset, or stretched.

The patterns that emerge can repeat over lengths that are vast compared to the underlying patterns. In graphene stacks, the new patterns change the physics that plays out in the sheets, notably the electrons behaviors. In the special case called magic angle graphene, the moir pattern repeats over a length that is about 52 times longer than the pattern length of the individual sheets, and the energy level that governs the behaviors of the electrons drops precipitously, allowing new behaviors, including superconductivity.

Galitski and Parhizkar realized that the physics in two sheets of graphene could be reinterpreted as the physics of two two-dimensional universes where electrons occasionally hop between universes. This inspired the pair to generalize the math to apply to universes made of any number of dimensions, including our own four-dimensional one, and to explore if similar phenomenon resulting from moir patterns might pop up in other areas of physics. This started a line of inquiry that brought them face to face with one of the major problems in cosmology.

We discussed if we can observe moir physics when two real universes coalesce into one, Parhizkar says. What do you want to look for when youre asking this question? First you have to know the length scale of each universe.

A length scaleor a scale of a physical value generallydescribes what level of accuracy is relevant to whatever you are looking at. If youre approximating the size of an atom, then a ten-billionth of a meter matters, but that scale is useless if youre measuring a football field because it is on a different scale. Physics theories put fundamental limits on some of the smallest and largest scales that make sense in our equations.

The scale of the universe that concerned Galitski and Parhizkar is called the Planck length, and it defines the smallest length that is consistent with quantum physics. The Planck length is directly related to a constantcalled the cosmological constantthat is included in Einsteins field equations of general relativity. In the equations, the constant influences whether the universeoutside of gravitational influencestends to expand or contract.

This constant is fundamental to our universe. So to determine its value, scientists, in theory, just need to look at the universe, measure several details, like how fast galaxies are moving away from each other, plug everything into the equations and calculate what the constant must be.

This straightforward plan hits a problem because our universe contains both relativistic and quantum effects. The effect of quantum fluctuations across the vast vacuum of space should influence behaviors even at cosmological scales. But when scientists try to combine the relativistic understanding of the universe given to us by Einstein with theories about the quantum vacuum, they run into problems.

One of those problems is that whenever researchers attempt to use observations to approximate the cosmological constant, the value they calculate is much smaller than they would expect based on other parts of the theory. More importantly, the value jumps around dramatically depending on how much detail they include in the approximation instead of homing in on a consistent value. This lingering challenge is known as the cosmological constant problem, or sometimes the vacuum catastrophe.

This is the largestby far the largestinconsistency between measurement and what we can predict by theory, Parhizkar says. It means that something is wrong.

Since moir patterns can produce dramatic differences in scales, moir effects seemed like a natural lens to view the problem through. Galitski and Parhizkar created a mathematical model (which they call moir gravity) by taking two copies of Einsteins theory of how the universe changes over time and introducing extra terms in the math that let the two copies interact. Instead of looking at the scales of energy and length in graphene, they were looking at the cosmological constants and lengths in universes.

Galitski says that this idea arose spontaneously when they were working on a seemingly unrelated project that is funded by the John Templeton Foundation and is focused on studying hydrodynamic flows in graphene and other materials to simulate astrophysical phenomena.

Playing with their model, they showed that two interacting worlds with large cosmological constants could override the expected behavior from the individual cosmological constants. The interactions produce behaviors governed by a shared effective cosmological constant that is much smaller than the individual constants. The calculation for the effective cosmological constant circumvents the problem researchers have with the value of their approximations jumping around because over time the influences from the two universes in the model cancel each other out.

We dont claimeverthat this solves cosmological constant problem, Parhizkar says. Thats a very arrogant claim, to be honest. This is just a nice insight that if you have two universes with huge cosmological constantslike 120 orders of magnitude larger than what we observeand if you combine them, there is still a chance that you can get a very small effective cosmological constant out of them.

In preliminary follow up work, Galitski and Parhizkar have started to build upon this new perspective by diving into a more detailed model of a pair of interacting worldsthat they dub bi-worlds. Each of these worlds is a complete world on its own by our normal standards, and each is filled with matching sets of all matter and fields. Since the math allowed it, they also included fields that simultaneously lived in both worlds, which they dubbed amphibian fields.

The new model produced additional results the researchers find intriguing. As they put together the math, they found that part of the model looked like important fields that are part of reality. The more detailed model still suggests that two worlds could explain a small cosmological constant and provides details about how such a bi-world might imprint a distinct signature on the cosmic background radiationthe light that lingers from the earliest times in the universe.

This signature could possibly be seenor definitively not be seenin real world measurements. So future experiments could determine if this unique perspective inspired by graphene deserves more attention or is merely an interesting novelty in the physicists toy bin.

We havent explored all the effectsthats a hard thing to do, but the theory is falsifiable experimentally, which is a good thing, Parhizkar says. If its not falsified, then its very interesting because it solves the cosmological constant problem while describing many other important parts of physics. I personally dont have my hopes up for that I think it is actually too big to be true.

Reference: Strained bilayer graphene, emergent energy scales, and moir gravity by Alireza Parhizkar and Victor Galitski, 2 May 2022, Physical Review Research.DOI: 10.1103/PhysRevResearch.4.L022027

The research was supported by the Templeton Foundation and the Simons Foundation.

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Our Reality May Only Be Half of a Pair of Interacting Worlds - SciTechDaily

WATERLOO Cendikiawan Suryaatmadja of Indonesia is taking a break this summer before starting his PhD.

The 17-year-old is the third-youngest person in University of Waterloos history to graduate with a masters degree in physics, and he dreams about using the fundamental building blocks of the physical world to make it better.

I still have a long way to go, said Suryaatmadja during an interview at the Dana Porter Library on campus.

His research will focus on quantum information theory using quantum physics to manage the flow of information.

I think it is a very important field of physics, said Suryaatmadja. Its new, its emerging.

UW is a leading centre of research on quantum information theory, and the next generation of supercomputers that will use that research quantum computers.

You are essentially looking at things from the most fundamental and simplest level, and you just start to build a whole structure out of it, said Suryaatmadja.

After almost six years in Canada, Suryaatmadja is still not used to the changing weather and the need for so many clothes. He misses the warm, consistent weather of his home and the flavourful food of Indonesia.

Even a simple meal can have 12 to 14 spices, oh man, said Suryaatmadja. Im not saying the food in Canada is bad, but you guys use a lot of butter.

He also misses his family, and tries to speak with them every week. But he likes the diversity of Canada, especially around the UW campus.

You meet people with different ideas, different cultures, different perspectives, said Suryaatmadja. It really helps you think more critically, it really helps you get exposed to thoughts that are different from your own. I think Canada excels at that.

He grew up in Bogor, a city south of Jakarta on the Indonesian Island of Java. His first language is Indonesian, and Suryaatmadja taught himself English.

When Suryaatmadja started elementary school he was placed in Grade 3. After Grade 4 he studied on his own, and was recruited by UW when he was 12. Four years later he had completed a bachelors degree in mathematical physics with a minor in pure mathematics. It took more than a year to complete the masters and his PhD will also be done at UW.

Jeff Casello, UWs associate vice-president of graduate studies and post-doctoral affairs, calls Suryaatmadjas academic accomplishments remarkable.

Having the academic skills and personal drive to earn a masters degree at age 17 reflects a level of accomplishment that is incredibly rare, said Casello.

Suryaatmadja laughs at how it came about. He pressed the wrong button in the elevator at the institute in Bogor where he studied and prepared for math competitions. He walked off the elevator and into the arms of two UW recruiters Jean Lowry and Ken Seng Tan.

I just talked to them actually, said Suryaatmadja. This was before I graduated from high school.

At this point, he looks forward to a life of research that breaks new ground in physics and quantum information theory.

I just want to be a researcher. I dont know where. Lets see where things go. I still have a lot of time to make plans.

During the past six years hes joined many clubs on campus, and enjoys doing improv. He likes watching TV shows and movies that are comedies, or Sci-Fi blockbusters such as Dune and Blade Runner 2049. He enjoys Manga, DC Comics and books by Neil Gaiman, Terry Pratchett and graphic novels by Grant Morrison.

And I like walking a lot, especially in this weather, said Suryaatmadja.

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Whiz kid from Indonesia earns master's at University of Waterloo in physics at 17 - Waterloo Region Record

To our earliest human ancestors, the world was a bewildering place. From devastating natural disasters to the countless stars in the night sky, their universe was filled with phenomena that defied explanation.

As humans whose minds worked in just the same way as ours, they must have spent endless hours pondering their place within this mystifying world. They would have asked many of the same questions we continue to struggle with today: Who am I? What is my place in the universe? What is the nature of my sense of self?

To answer these questions, our ancestors filled their world with magic, monsters, and supernatural beings. They told stories about mythical creations that sparked a sense of wonder and mystery about the nature of the universe. Yet not so long ago on the timescale of human history, that all began to change.

Starting with the philosophers of the ancient world, humans began to question whether the natural forces that once seemed so far beyond our comprehension could be explained after all. Over the centuries, this movement grew into countless fields of scientific research.

As we began to uncover the fundamental building blocks of our universe, the need for magical forces to explain what we couldnt comprehend began to subside. Today, for example, the fields of quantum mechanics and general relativity tell us much about the nature of the matter that surrounds us, from subatomic to cosmological scales.

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Yet at the same time, ideas about the magical forces which instilled such wonder in our ancient ancestors still run deep in human culture. This natural sense of awe seems to have led to some unfortunate misconceptions about the brilliant minds who have contributed so much to our understanding of the universe.

Theres a notion that scientists have this sterile, clinical view of the world, that leaves no room for mystery, awe, or magic, Jim Al-Khalili, a theoretical physicist and author of The World According to Physics, told Big Think.

From stereotypes in fiction that frame scientists as brashly dismissive of any idea that seems slightly illogical, to groups who view science as an attack on their faith, these ideas remain popular today. But to Al-Khalili, they couldnt be further from the truth.

On the contrary, everything I learn about how the world is tells me its full of wonder, he told Big Think. The idea that Newton discovered that the invisible force pulling the apple down to the ground is exactly the same force keeping the Moon in orbit around the Earth is utterly profound and awe-inspiring.

To illustrate the wonder that pervades scientific research, Al-Khalili imagines the sum of human knowledge as an island.

The interior of the island is the well-established science we know very well; its shoreline is the limits of our understanding; and beyond it is the ocean of the unknown.

The shorelines of our island are constantly expanding outward. But just like the earliest seafarers, there is no way for us to know just how far the ocean surrounding extends, or if it even ends. For physicists like Al-Khalili, the ocean of the unknown is particularly vast.

So far, our knowledge of quantum mechanics has culminated in the Standard Model, which aims to describe the nature of the fundamental particles and forces that comprise our universe. The Standard Model can reliably explain the results of almost all experiments that physicists have thrown at it. But we know that these explanations are far from complete.

Among the Standard Models most glaring gaps is that it cant explain the nature of dark matter: the mysterious substance which astronomers claim must account for roughly 85% of all mass in the universe, but whose true nature continues to elude us, despite decades of efforts to detect it.

The Standard Model also cant explain dark energy, which is the cosmic-scale force thats thought to be driving the universes continuing expansion. Even further, physicists have yet to develop a single unifying theory that can simultaneously encompass the founding principles of quantum mechanics and general relativity.

As physicists delve deeper into these questions, theyre steadily realizing the extent of the discoveries theyve yet to make; the ocean surrounding our island of knowledge only appears to grow ever more vast.

As we expand the shorelines of our island, Al-Khalili thinks that the knowledge we have gained so far could turn out to be completely wrong, leading to completely new conceptions about the most basic building blocks of our universe.

One-hundred years from now, I may look back at the Jim of the early 21st century and think I was just as nave as the medieval scholars who thought the Sun orbited the Earth.

Yet physicists arent the only ones who perceive this expanding ocean. Ultimately, the fundamental phenomena they aim to explain can only go so far toward answering the questions first pondered by our distant ancestors about who we really are, and where we fit within the universe.

Despite millennia of scrutiny by billions of minds, our ocean of the unknown is only growing: a picture that is being repeated time and again across many fields of scientific research. In solving these mysteries, researchers from across the broad scope of modern science are increasingly realizing just how intertwined their fields really are.

Just as Newton first discovered the astonishing link between a falling apple and the orbiting Moon, extending our island further may involve finding links between phenomena we have previously thought of as unconnected. All the same, there is no guarantee that we will ever know how far the ocean surrounding us extends.

For Al-Khalili, if we look back at how far our scientific knowledge has come, and just how far we have yet to go, its impossible to claim that science is purely a cold, rational exercise.

We dont know if we will ever one day know everything about the nature of reality, and in a way, thats nice. Its frustrating but beautiful that we may never have all the answers.

Far from eliminating the sense of awe and wonder first felt by our distant ancestors, expanding our knowledge of science can only help it to grow. As Douglas Adams once put it, Id take the awe of understanding over the awe of ignorance any day.

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Jim Al-Khalili: How our ancient sense of wonder drives physics deeper into the unknown - Big Think

WEST LAFAYETTE, Ind. Black holes are everywhere right now at the middle of every galaxy, of course, as well as all over the news thanks to the recent picture taken of the black hole at the center of Earths own galaxy.

Matthew Lister, professor of physics and astronomy in the College of Science at Purdue University, explains the significance of the image, only the second one ever taken of a black hole. He was not part of the team that took the image, but as an expert on black hole phenomena, he is very excited about the development. The image is notable in that the addition of another radio telescope at the South Pole resulted in an improvement in resolution over the first picture of a black hole. The observations were challenging, due to the nature of the black hole itself.

The radio emission of the black hole at the center of our galaxy is quite weak, and the black hole environment varies quite rapidly, Lister said. Its like trying to take an image of a moving target where youre not getting a lot of light from it, so this required a lot of processing and comparison to computer models to be confident that the image reflects whats really going on at the galactic center.

An international cadre of scientists collaborated to piece together the final picture of the black hole. The images come from the Event Horizon Telescope, an array of telescopes across the globe that work together to study black holes, something Lister has done for more than 20 years. Lister ispart of the team that is designing the next-generation Event Horizon Telescope, which promises to image many more black hole systems in even sharper detail.

Lister and his collaborators recently discovered a supermassive black hole binary system, one of only two known such systems. The two black holes, which orbit each other, likely weigh 100 million suns each. The two are only between 200 astronomical units and 2,000 AU apart (one AU is the distance from the Earth to the sun), at least 10 times closer than the only other known supermassive binary black hole system.

Studying black holes is important for another, not quite as esoteric reason, too: Their extreme properties may offer an insight into the much-vaunted Theory of Everything or a unified field theory that would unite all observed physical laws of the universe.

We dont have a theory that connects gravity and quantum mechanics, Lister said. In the case of black holes, you have very large amounts of mass confined to a very, very small volume. In order to better understand how things like gravity and quantum mechanics are unified, black holes are a key subject to study.

About Purdue University

Purdue University is a top public research institution developing practical solutions to todays toughest challenges. Ranked in each of the last four years as one of the 10 Most Innovative universities in the United States by U.S. News & World Report, Purdue delivers world-changing research and out-of-this-world discovery. Committed to hands-on and online, real-world learning, Purdue offers a transformative education to all. Committed to affordability and accessibility, Purdue has frozen tuition and most fees at 2012-13 levels, enabling more students than ever to graduate debt-free. See how Purdue never stops in the persistent pursuit of the next giant leap athttps://stories.purdue.edu.

Media contact: Brittany Steff, bsteff@purdue.edu

Source: Matthew Lister, mlister@purdue.edu

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Painting a clearer picture of black holes - Purdue University

Alexander Gardner mailed his application to North Carolina A&T from what was likely a military prison cell somewhere in the US South. It was the mid-1950s; Gardner would have been in his late 20s. He had run away from home at the age of 14 to join the US Merchant Marines.

Gardner had been incarcerated for punching a commanding officer who called him a racial slur. He had only an 8th grade education, but North Carolina A&Ta university located in Greensboro, NCsaw his potential. They accepted him, and he graduated in 1958 with a degree in engineering physics. Five years later, Gardner became the first Black person to earn a physics PhD from the University of North Carolina at Chapel Hill. He returned to North Carolina A&T the year after that, this time as a member of the physics faculty.

Thats an unbelievable story, says Arlene Maclin, a former physics professor who credits Gardner as one of her earliest and most important mentors.

However, its far from the only extraordinary tale of triumph over adversity to come out of the Black physics community. And it was possible, in part, due to the unique support Gardner found at North Carolina A&T, which is classified as an HBCU, a Historically Black College or University.

HBCUs have played an important role in bringing Black students into physics. Prior to 2003, HBCUs consistently graduated the majority of Black physics-degree holders. In the year 2000, HBCUs enrolled just 13% of all Black postsecondary students but awarded a staggering 60% of physics degrees earned by Black students that year. Those numbers have been on a steady decline in the years since, but HBCUs still produce a disproportionate share of Black physics graduates today.

In 2020, there were 101 active HBCUs in the United States. Thirty of them offer a bachelors degree in physics, and 11 of those offer amasters degree in physics. Just four of themAlabama A&M University, Florida A&M University, Hampton University and Howard Universityoffer general physics PhD programs. HBCUs granted only an estimated 11 of the 1,910 physics PhDs awarded to US graduate students in 2018 and 2019.

Advocates for recruiting and retaining more Black students into physics often discuss how to balance support for Black students at HBCUs like North Carolina A&T, and at Primarily White Institutions like UNC Chapel Hill. But the Black physicists whove emerged from both HBCUs and PWIs suggest that the physics community should be more concerned about structural challenges that minority physics students face everywhere, and the toxic environments that can be found in any academic department.

A new initiative called TEAM-UP Together, aimed at doubling the number of African Americans earning undergraduate degrees in physics and astronomy by 2030, will work toward those goals.

Black students, especially Black women, are vastly underrepresented in physics. Despite making up 15.64% of the college-age population, Black students earned an average of 3% of bachelors degrees in physics between 2014 and 2018, according to the American Physical Society. The majority74.5%of those degrees went to Black men. During the same timeframe, Black students earned just 1.8% of doctoral degrees in physics.

Experts and alumni of HBCU physics programs agree that HBCUs succeed in attracting and retaining Black students because they can create a supportive environment for students from all walks of life, even the most disadvantaged.

HBCUs get the broadest breadth of the African American community, says Hakeem Oluseyi, president of the National Society of Black Physicists. Everybody gets the top. Everybody gets the middle class. But for those of us who are the real deep strugglerswho are just as brilliant, who are just as capable, and likely very much more hard-workingthe HBCUs are, in many ways, our bridge into that world, because they understand us from where we're coming from. Most of these other places dont.

Thomas Searles, an associate professor of electrical & computer engineering at the University of Illinois Chicago, agrees with Oluseyi. Searles earned his undergraduate degree at Morehouse College and served as an assistant professor of physics at Howard University, both HBCUs. HBCUs are about mentoring all students, not just the best and the brightesteverybody, he says.

Still, HBCUs are not exempt from issues related to bias and discrimination.

Ive experienced more sexism at HBCUs than I experienced in other places that I've worked, and I've worked at the NSF, the CIA, MIT Lincoln Lab, Oak Ridge, Maclin says. As a Black woman, I was prepared to deal with racism, but not sexism.

More women than men have enrolled at HBCUs in every year since 1976. But Maclin explains that even at HBCUs, Black women in faculty must work harder to gain tenure and secure administrative support for their initiatives. The most recent data reported by the National Center for Education Statistics for the fall of 2001 found that Black women represented 27% of all full-time instructional and research faculty and 17% of full professors at HBCUswith Black men making up 31% and 36% of those roles, respectively. Maclin suggests that HBCU physics students who are women likely face similar difficulties.

Black women still do not have a critical mass in physics, anywhere, Maclin says. We dont have five Black women physicists anywhere working together. Nowhere.

Maclin says she once offered to help the chair of an HBCU physics department recruit more Black women. He never took me up on that challenge, she says.

Tennille Presley, an associate professor of physics at Winston-Salem State University, an HBCU in North Carolina, says she has similarly noted a disconnect between the gender breakdown of students and professors at HBCUs.

I agree with Dr. Maclin, Presley says. "In general, there should be more diversity in physics departments, especially as it relates to the inclusion of Black women and other women of colorand that includes both students and faculty."

Of course, Black women in PWI physics departments also face challenges that their Black male peers do not. The same is true for Black physics students who may be LGBTQIA+, disabled, foreign-born, or who hold any other marginalized identity in addition to being Black.

Certain identities are seen as conflicting [with our ideas of] who a scientist is, and who a physicist is, says Farrah Simpson, a doctoral candidate in physics who earned her undergraduate degree at Columbia University, and who also serves as student representative on the National Society of Black Physicists executive board.

Being Black, queer and a womanall these intersectional identitiesa lot of the time I feel within scientific spaces that people expect you to behave a certain way, or to have a certain identity, and your identity is [seen] as contradicting that, she says.

Maintaining a doctoral degree program in physics requires resources that historically and chronically underfunded HBCUs may be unable or unwilling to provide.

Physics departments are not cheap to maintain for the university, says Claudia Rankins, former dean of the School of Science at Hampton University. "Many small physics departments only graduate a few students every year, yet the professors who teach the upper-level courses, as well as the labs, need to be there.[It's] the same struggle other small programs or majors encounter."

Recruiting and retaining faculty is also a challenge for cash-strapped HBCU programs, where faculty made an average of $24,000 less per year than their PWI counterparts in 2019-2020.

So, the majority of physics doctoral degreesmore than 99%, according to the AIPare awarded by PWIs.

Institutions have partnered via bridge programs, which are specifically designed to help students transition from undergraduate and/or masters degrees at an HBCU to a doctoral degree at a PWI. These programs aim to provide mentoring that students moving to an institution where they are in the minority may need and may not receive. However, HBCU faculty and bridge program alumni often criticize these programs for failing to deliver adequate support to the students who participate. In part, the issue comes down to a lack of emphasis on mentoring at PWIs, especially the most elite.

Ive heard from professors at MIT who have said, Well, HBCUs are smaller; they have fewer students. They can afford to really mentor students in a proper way. At a place like MIT, we dont have that luxury, says Dara Norman, deputy director for the Community Science and Data Center at NSF's National Optical-Infrared Astronomy Research Laboratory.

Norman says this attitude is common among faculty at R1 universities. But Norman, who took nearly all of MITs core physics classes as part of her undergraduate degree, also says that mentorship is crucial for students who may not know what to expect when arriving on university campuses.

My parents did not go to college in the regular way; both my parents were in the Navy, Norman says. When I got to college, I realized I didnt really know what college wasAnd I couldnt fall back on my parents experienceI wonderif I had hit the ground running, would I have been in better shape?

PWI physics departments can also create environments that are actively hostile toward Black students.

Charles Brown, a postdoctoral researcher in quantum simulation at the University of California, Berkeley, can detail numerous instances of racialized microaggressions and even open hostility during his time as a graduate student in the physics department at Yale University. In a 2020 Physics Today article, Brown recounted stories of strangers handing him trash as though he were a member of the cleaning staff; of being denied entry to buildings while streams of non-black people passed by without showing ID; of being constantly asked whether he was affiliated with Yale at all.

It puts cracks in the foundation of your identity in the field, of your sense of belonging to the field, Brown says. Being a student is hard. Youre learning lots of difficult stuff. Youre navigating some new environment. And when youre getting constant messages that you don't belong, and that you're not respected, it makes it that much harder to do the thing thats already hard for students of any background.

Different students deal with these encounters in different ways, but however Black students may process these incidents, they do add up, says Falcon Rankins, head of PRISSEM Academic Services, an organization that works to support Black HBCU STEM faculty.

[There is so much] labor that Black students, female students have to do in terms of that calculus around, you know: Is this racism? Rankins says. Is this person being sexist? Is this person assuming that I dont know how to do something because Im Black? All those questions that we have to ask ourselvesI think thats real labor that isnt always appreciated as labor.

Ultimately, providing students with a welcoming environment is crucial to retaining those students at any educational institution. We keep [pursuing] these pipeline-building efforts without asking, Where does this pipeline dump out at the end of the day? Rankins says, noting that this applies to the entirety of the physics ecosystem and STEM fields as a whole.

[Physics] departments need to take a really close, deep-dive, data-driven look at what's going on in their particular context, and fix that, says Arlene Modeste Knowles, who serves as project manager for the American Institute of Physics National Task Force to Elevate African American Representation in Undergraduate Physics & Astronomy (TEAM-UP). Because if you recruit students into a toxic environment, it's going to be a revolving door. Those students aren't going to make it through.

In 2020, the AIP published an example of exactly the kind of data-driven work Knowles is talking about with The Time is Now, a detailed report based on the organizations two-year study examining the underrepresentation of Black students in undergraduate physics departments.

In April, the TEAM-UP diversity task force was awarded a $12.5 million, five-year grant by the Simons Foundation and Simons Foundation International to launch TEAM-UP Together, a collective action aimed at helping the task force achieve its goal of doubling the number of African-Americans earning undergraduate degrees in physics and astronomy by 2030.

The grant will initially support scholarships for students studying physics and astronomy at HBCUs and other predominantly Black institutions, before eventually extending to students at all undergraduate institutions in the US. The funding will also support undergraduate departments that have committed to implementing recommendations set out by the 2020 TEAM-UP report.

I don't want to see any other African American students endure harm in a physics or astronomy department, Knowles says.I want to see them thrive in those environments. With TEAM-UP Together, which will support the physical science community and leverage the enormous influence of AAS, APS, AAPT, SPS and AIP to catalyze systemic change, we have a chance at making this a reality.

While there is no surefire solution to these problems, Presley suggests that the physics community would do well to fall back on the tool it knows best: Educate others, Presley says. I think the more that [these issues] are brought to the forefront, the better things can be.

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The other physics problem | symmetry magazine - Symmetry magazine

By Harvard John A. Paulson School of Engineering and Applied SciencesMay 3, 2022

An illustration of a near-zero index metamaterial shows that when light travels through, it moves in a constant phase. Credit: Second Bay Studios/Harvard SEAS

Zero-index metamaterials offer new insights into the foundations of quantum mechanics.

In physics, as in life, its always good to look at things from different perspectives.

Since the dawn of quantum physics, how light moves and interacts with matter around it has been primarily described and understood mathematically through the lens of its energy. Max Planck used energy to explain how light is emitted by heated objects in 1900, a seminal study in the foundation of quantum mechanics. Albert Einstein used energy when he introduced the concept of the photon in 1905.

But light has another, equally important quality known as momentum. And, as it turns out, when you take momentum away, light starts behaving in really interesting ways.

An international team of physicists is re-examining the foundations of quantum physics from the perspective of momentum and exploring what happens when the momentum of light is reduced to zero. The researchers are led by Michal Lobet, a research associate at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Eric Mazur, the Balkanski Professor of Physics and Applied Physics at SEAS,

The research was published in the journal Nature Light Science & Applications on April 25, 2022.

Any object with mass and velocity has momentum from atoms to bullets to asteroids and momentum can be transferred from one object to another. A gun recoils when a bullet is fired because the momentum of the bullet is transferred to the gun. At the microscopic scale, an atom recoils when it emits light because of the acquired momentum of the photon. Atomic recoil, first described by Einstein when he was writing the quantum theory of radiation, is a fundamental phenomenon that governs light emission.

But a century after Planck and Einstein, a new class of metamaterials is raising questions regarding these fundamental phenomena. These metamaterials have a refractive index close to zero, meaning that when light travels through them, it doesnt travel like a wave in phases of crests and troughs. Instead, the wave is stretched out to infinity, creating a constant phase. When that happens, many of the typical processes of quantum mechanics disappear, including atomic recoil.

Why? It all goes back to momentum. In these so-called near-zero index materials, the wave momentum of light becomes zero and when the wave momentum is zero, odd things happen.

As physicists, its a dream to follow in the footsteps of giants like Einstein and push their ideas further. We hope that we can provide a new tool that physicists can use and a new perspective, which might help us understand these fundamental processes and develop new applications.

Michal Lobet, Research Associate, SEAS

Fundamental radiative processes are inhibited in three dimensional near-zero index materials, says Lobet, who is currently a lecturer at the University of Namur in Belgium. We realized that the momentum recoil of an atom is forbidden in near-zero index materials and that no momentum transfer is allowed between the electromagnetic field and the atom.

If breaking one of Einsteins rules wasnt enough, the researchers also broke perhaps the most well-known experiment in quantum physics Youngs double-slit experiment. This experiment is used in classrooms across the globe to demonstrate the particle-wave duality in quantum physics showing that light can display characteristics of both waves and particles.

In a typical material, light passing through two slits produces two coherent sources of waves that interfere to form a bright spot in the center of the screen with a pattern of light and dark fringes on either side, known as diffraction fringes.

In the double slit experiment, light passing through two slits produces two coherent sources of waves that interfere to form a bright spot in the center of the screen with a pattern of light and dark fringes on either side, known as diffraction fringes. Credit: Harvard John A. Paulson School of Engineering and Applied Sciences

When we modeled and numerically computed Youngs double-slit experiment, it turned out that the diffraction fringes vanished when the refractive index was lowered, said co-author Larissa Vertchenko, of the Technical University of Denmark.

As it can be seen, this work interrogates fundamental laws of quantum mechanics and probes the limits of wave-corpuscle duality, said co-author Iigo Liberal, of the Public University of Navarre in Pamplona, Spain.

While some fundamental processes are inhibited in near-zero refractive index materials, others are enhanced. Take another famous quantum phenomenon Heisenbergs uncertainty principle, more accurately known in physics as the Heisenberg inequality. This principle states that you cannot know both the position and speed of a particle with perfect accuracy and the more you know about one, the less you know about the other. But, in near-zero index materials, you know with 100% certainty that the momentum of a particle is zero, which means you have absolutely no idea where in the material the particle is at any given moment.

This material would make a really poor microscope, but it does enable to cloak objects quite perfectly, Lobet said. In some way, objects become invisible.

These new theoretical results shed new light on near-zero refractive index photonics from a momentum perspective, said Mazur. It provides insights into the understanding of light-matter interactions in systems with a low- refraction index, which can be useful for lasing and quantum optics applications.

The research could also shed light on other applications, including quantum computing, light sources that emit a single photon at a time, the lossless propagation of light through a waveguide, and more.

The team next aims to revisit other foundational quantum experiments in these materials from a momentum perspective. After all, even though Einstein didnt predict near-zero refractive index materials, he did stress the importance of momentum. In his seminal 1916 paper on fundamental radiative processes, Einstein insisted that, from a theoretical point of view, energy and momentum should be considered on a completely equal footing since energy and momentum are linked in the closest possible way.

As physicists, its a dream to follow in the footsteps of giants like Einstein and push their ideas further, said Lobet. We hope that we can provide a new tool that physicists can use and a new perspective, which might help us understand these fundamental processes and develop new applications.

Reference: Momentum considerations inside near-zero index materials by Michal Lobet, Iigo Liberal, Larissa Vertchenko, Andrei V. Lavrinenko, Nader Engheta and Eric Mazur, 25 April 2022, Light: Science & Applications.DOI: 10.1038/s41377-022-00790-z

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In Einsteins Footsteps and Beyond: New Insights Into the Foundations of Quantum Mechanics - SciTechDaily

This spring, each department in the University of Arizona's College of Science nominated an outstanding senior who went above and beyond during their time as a Wildcat. We are pleased to share their stories as they reflect on their time at UArizona. Next up in the senior spotlight series is Justin Fink.

Hometown: Marana, AZ

Degrees: Physics and Astronomy

College of Science:Why did you choose your area of study?

Justin: At Marana High School, I started learning physics sophomore year. My teacher, Mark Calton, taught me Newtons kinematic equations. I thought it was fascinating to learn so much about the motion of objects from a few initial conditions. I had started an engineering club with Mark where we created trebuchets, a duct tape water bottle, a duct tape boat, and many other projects. I used my introductory physics knowledge to know how much force our trebuchet was applying and the distance the golf ball would travel. I wanted to learn more. I went through two years of AP physics classes learning thermodynamics, optics, electromagnetism, and quantum mechanics, of course, all in a simplistic manner. I was able to take an Astronomy course with Mark as well. My physics classes and teacher got me out of my bubble and convinced me to put in the effort necessary to take on and achieve this degree.

COS:Tell us about a class or research project you really enjoyed.

Justin: The most memorable research project I have worked on throughout these four years of college was with the Thomas Jefferson National Accelerator Facility (JLab). I have worked with them since the summer after my junior year. This was the first time I had to search through textbooks and teach myself a topic for research. This experience gave me an abundance of opportunities, from seminars to writing papers, all the way to a poster presentation at Rice University. This internship even led me to learn more about medical physics and change the direction of my career.

COS:What is one specific memory from your time at UA that you'll cherish forever?

Justin: I will always remember going up to Mt Lemmon with a group of astronomy friends. They had an 8 telescope so we could see the rings of Jupiter. It is a whole new experience to see the rings in person rather than a nice picture online. Surprisingly, it was my first time on Mt Lemon, even though I have lived here my whole life.

COS:What is next for you after graduation?

Justin: After graduation, I am working with the Thomas Jefferson National Accelerator Facility over the summer. Then, I am moving on to UCLA this coming Fall. I was accepted into their Department of Physics and Biology in Medicine to work towards a Medical Physics Ph.D.

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Outstanding Seniors in the College of Science: Justin Hink - University of Arizona News

In a parallel universe, you are writing this article. Youre probably doing a better job of it too. Thats what the multiverse theory suggests, anyway. You will no doubt have heard of it, if not from science then certainly from science fiction.

Star Trek, Stranger Things, Spider-Man: No Way Home TV and film is full of stories set around the idea that our world is but one of many alternative realities. However, with the release of the new Marvel film, Doctor Strange In The Multiverse Of Madness, the theory is set to achieve new heights of popularity.

But what exactly is the multiverse? And is there any truth to the idea that in a different reality Im actually a rich, handsome Premier League footballer?

The multiverse derives from the basic idea that beyond the grand sphere of our observable Universe are entirely different universes, distantly separated from ours. What characterises these universes is up for debate, but Richard Bower, professor of cosmology at Durham University, cites the work of fellow cosmologist Max Tegmark, who has theorised four levels of multiverse.

The first, explains Bower, posits an infinite universe in which every possibility that could happen would happen, including another copy of Earth. Level two, meanwhile, gives us multiverses where the basic laws of physics are the same, but fundamental constants differ. Newtons law of gravity would still weaken with distance, says Bower, but maybe there are four spatial dimensions instead of three.

Level four goes even further, presenting multiverses that have entirely different laws of physics. So maybe there would be some sort of mathematics that we have no idea about, says Bower. It could get weird. The trailers for the new Doctor Strange movie suggest an embrace of these weirder versions of the multiverse, with one shot showing him trapped in some sort of cuboid dimension.

Elizabeth Olson as Wanda Maximoff in Doctor Strange In The Multiverse Of Madness Disney

But of course, the most popular iteration of the multiverse is level three, the many worlds interpretation of quantum mechanics. It states that every choice causes a split in the Universe, leading to infinite parallel realities. In popular culture, its the theory behind the multiple Spider-Men in Spider-Man: No Way Home.

There are many versions of you but youre only aware of one of those versions, explains Bower, who cites the famous Schrdingers cat experiment. Youre seeing a cat thats either alive or dead, and youre incapable of realising that theres a version of you where the cat is alive. Youre just conscious of the version where the cat is dead.

None of this has been proven, however. There are theories that if a neighbouring universe happened to collide with ours some time ago, it may have left behind proof in the form of cold or hot spots on the cosmic microwave background (electromagnetic radiation left over from the Big Bang).

Bower himself is optimistic that advances in quantum computing which utilises properties of quantum mechanics like entanglement and superposition could demonstrate the strength of the many worlds interpretation. But at the moment, all of this is hypothetical. In fact, many scientists believe the mystery of whether the multiverse is real to be a philosophical question rather than a scientific one.

I dont totally agree with my colleagues on that, because a lot of them seem to think, Oh, its a philosophical question, and therefore we cant try to address it scientifically, says Bower. No, we just have to be more inventive about how we try to come up with ways to test it and new ways to interpret things.

Who knows, maybe in another universe someone has already figured it all out?

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Doctor Strange: Could we really be living in a multiverse? - BBC Science Focus Magazine

"The Big Bang Theory" goes pretty far into incredibly brainy information and advanced theories. As it turns out, all of that information is accurate, fact-checked, and presented in a true manner thanks to the likes of David Saltzberg, a real-life UCLA physics professor.

In an interview with NPR, Saltzberg said of his tenure on the hit series, "This has a lot more impact than anything I will ever do. It's hard to fathom, when you think about 20 million viewers on the first showing and that doesn't include other countries and reruns. I'm happy if a paper I write gets read by a dozen people." According to that same interview, Saltzberg's other function on the show, besides making sure all of the science is correct, was to fill in the appropriate information within the script and on the whiteboards. The whiteboards themselves have an incredible amount of detail when it comes to current scientific understanding, and Saltzberg would often reference real-life theoretical works, much to the delight of actual physicists familiar with the subjects.

When he's not working on shows like "The Big Bang Theory," Saltzberg works with proton colliders, researches neutrinos, and teaches physics classes that range from introductory courses to classes aimed at graduate students at the University of California's Los Angeles campus (via UCLA). Because of Saltzberg's work on "The Big Bang Theory," the show is as scientifically correct as it possibly can be.

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This Is The Real Scientist Behind The Big Bang Theory - Looper

Whether its solving the worlds biggest problems or investigating the potential of novel discoveries, researchers at UCF are on the edge scientific breakthroughs that aim to make an impact. Through the Research in 60 Seconds series, student and faculty researchers condense their complex studies into bite-sized summaries so you can know how and why Knights plan to improve our world.

Name: Enrique Del Barco

Position(s):Pegasus Professor of Physics and associate dean of Research, Facilities

Why are you interested in this research?Understanding how the microscopic world functions is almost bucolic, as the laws governing this world (quantum mechanics) are absolutely unimaginable from our classical world perspective but explain the most fundamental phenomena with unnumerable repercussions in our day-to-day lives.

Who inspires you to conduct your research?My students. I reflect myself in my students, from high school to the Ph.D. level. They remind me of my youngest self, when I looked at the world with amusement and was looking to understand how everything works. I see this in my students faces when they are in the lab trying to unveil the next secret of the microscopic world.

Are you a faculty member or student conducting research at UCF? We want to hear from you! Tell us about your research at bit.ly/ucf-research-60-form.

How does UCF empower you to do your research?UCF has offered me the opportunity to build an extremely competitive research laboratory and has continuously supported me during the years in basically every single need I have had while putting me in contact with an amazing population of brilliant students.

What major grants and honors have you earned to support your research?I have received numerous grants from multiple external sponsors, including the U.S. National Science Foundation and the U.S. Department of Defense, that amount to over $12 million. This funding has been essential to support the research activities conducted in my group. As the main recognition that I have received from my colleague scientists was becoming fellow of the American Physical Society in 2017 for my accomplishments in nanoscale magnetism research.

Why is this research important?Our research in nanoscale spintronics has strong potential to represent a breakthrough in technology. To provide an example, spintronics-based circuitry may end consuming one thousand times less energy than the most advanced electronic technology. Only this would represent a revolution, as currently energy consumption by electronic circuits (including computers) represents one of the most important expenses of energy in the world, contributing significantly to our climate change. Decreasing this by a thousand would be amazing!

Are you a faculty member or student conducting research at UCF? We want to hear from you! Tell us about your research at bit.ly/ucf-research-60-form.

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Research in 60 Seconds: Quantum Physics for the Future of Tech - UCF