D r. Chanda Prescod-Weinstein is a 32-year-old theoretical astrophysicist. Her academic home is arguably the nation's most elite physics department, at the Massachusetts Institute of Technology.
In one sense, she is among a dying breed. Prescod-Weinstein is a pen-and-paper theorist. "Basically I do calculus all day, on paper," she told HuffPost. "I'm a little bit of a hold-out. There are things I could be doing by computer that I just like to do by hand."
But she is also part of a vanguard, a small but growing number of African-American women with doctorates in physics.
Just 83 Black women have received a Ph.D. in physics-related fields in American history, according to a database maintained by physicists Dr. Jami Valentine and Jessica Tucker that was updated last week.
By comparison, the physics programs at MIT and UC Berkeley alone grant nearly as many Ph.D.'s each year. In total, U.S. universities awarded over 1,700 physics Ph.D.'s in 2013. The number of African-American faculty at U.S. physics departments remains similarly low; only two percent are Black, according to a report issued last year by the American Institute of Physics, and half of those faculty members are employed by historically Black colleges and universities (HBCUs).
Yet more than a third of all African-American women with physics doctorates earned them in the last 10 years, according to the database. In February, Prescod-Weinstein (citing subsequently-revised figures) posted a celebratory message on Twitter:
In 2010, I became the 69th Black American woman to get a PhD in physics. As of next Weds there will be 78 of us. #BlackWomenAppreciationDay
â�� Chanda (ç��å¬�å¨�) (@IBJIYONGI) February 20, 2015
"How did I feel when I posted that?" she said during a recent interview. "You know, whenever I think about these numbers—and I guess this makes me some white supremacist stereotype or whatever—I feel angry. I feel really, really angry. When I started as a physics major, I understood that I would be some kind of barrier-breaker, but I didn't really understand what that was going to feel like, or how hard it would be and how upsetting it would be, and how difficult it would be to watch other people go through the same process. So I think I felt angry; I felt like people need to hear this. People need to know this."
Prescod-Weinstein recounts teaching herself calculus and physics when her high school ran out of classes at her level; she grew up reading the New York Times each morning on the school bus, and spent a year carrying around the complete works of William Shakespeare. She identifies as queer/agender, and has written about the collapse of her first marriage "under the pressure of many things, including my wife's family's homophobia."
Prescod-Weinstein's parents were both political activists, and she has followed their path. Most of her public social media posts focus on social justice, in the world of science and beyond. She has highlighted the professional challenges of investing her time in activism:
For my part, as a Black woman, I would ask my white (and male) peers to remember that many of us (though not all) experience our differences as a negative in this environment. Where I see it as a Black cultural tradition to lend a helping hand even as I continue to achieve my own dreams, others see my commitment to [the National Society of Black Physicists] as a signal that I am wasting my time not doing science. Do my friends who play music in their spare time get this same signal? Moreover, many of us who are women or people of color or both are often involved in efforts to change the face of science. When we are challenged about that by our peers, not only are they standing in our way, but they are also failing to recognize that for many of us, this investment in the community is necessary to our survival, much like someone else might say playing music is for theirs.
We spoke to Dr. Chanda Prescod-Weinstein for Sophia, a HuffPost project to collect life lessons from fascinating people. She shared insights about her early life and influences, the challenges faced by marginalized communities in science, how she finds personal fulfillment and what she'd do differently if she had the chance.
How did your early life experiences lead you to this point?
The first thing that comes to mind: I was raised by a single mom. That had a really big impact on how I see myself in relation to the community. I do a lot of activism in terms of creating equal opportunities in the scientific community and more broadly. My mom was singlehandedly the strongest influence in terms of understanding the sacrifices people make for those that they love and for the communities that they cherish.
My mom—to be honest, she couldn't really help me with my homework after maybe the fourth grade. A lot of that had to do with her own experience of getting an education as a new immigrant to the United States. As a Black Caribbean immigrant, she was treated pretty badly at her school when she first came to the U.S., and I think came out of it educated to believe that she couldn't really do math.
She likes to joke about it now—and she's clearly one of the smartest people that I've ever met. But she did not let that stop her from recognizing that I had a strong interest in math at a very young age. When that translated into an interest in science, when I was about ten years old, she didn't feel threatened by it, and instead encouraged it.
That's played a huge role in how I think about mentoring now, even as a post-doctoral fellow, because I'm the only Black woman in the physics department at MIT. Black students come and talk to me because there just aren't faculty for them to talk to.
I got exposed to science in a serious way for the first time when I was 10 at school in fifth grade. It became obvious really quickly that I was really excited about it. My mom read in the newspaper that a documentary about Stephen Hawking was going to be showing. She thought it was interesting, and she really thought I should see it. I complained the whole way because it was a Saturday morning and independent movies seem really ridiculous to 10-year-olds. I thought it was super uncool. What was this "A Brief History of Time"? I didn't want to see some ridiculous thing about time.
My mom, being the strong-willed person that she is, dragged me into the theater, and halfway through the documentary they were talking about singularities and black holes, and how the singularity probably wasn't a physical thing but was in fact a breakdown of Einstein's General Relativity, just a point at which we did not have a theory for this science.
I was like, "Whoa. There's something that Einstein didn't understand? There's something Einstein didn't figure out?" I couldn't believe it. I said, "I want to work on that problem. I want to understand where that came from." So I came out of the movie theater begging my mom to buy me a copy of the book.
I was like, "Buy me 'A Brief History of Time'; I want to read it." My mom was really anxious that I wouldn't understand it, and would get discouraged because of that, so she wouldn't buy it for me. We didn't have a lot of money, so for her actually buying a book like that would have been a major expense. So my uncle—my mom's older brother—bought it for me behind her back for my eleventh birthday.
I walked out of that movie theater and I was like, "I'm going to be whatever that guy is." I looked up Stephen Hawking and sent an email to his address. Presumably one of his graduate students responded to me and explained to me how you become a theoretical physicist. So I began planning. I'm going to go to Harvard for college. I'm going to go to Cal Tech—those were my top two choices—and I'm going to get a Ph.D., and I'm going to become a theoretical physicist. And that's basically how it played out.
Every time I stumbled academically from then on, my mom kind of gave me a little shove and said, "This is what you want to do, so keep going."
It's fairly rare for people to identify their passion so early in life. Why do you think that happened in your case?
I think there's almost certainly an element of genetics involved. I tend to be someone who runs on passion. I think people who run on passion often find things they're passionate about early on. So for example, I was not the valedictorian of my high school class because I couldn't be bothered to take AP courses that I didn't care about. I either care, or I don't care.
I was also lucky. I was born to a parent who speaks English, who has a college degree. She was able to fight for me at my school at various points. She understood the school system well enough to navigate getting me into magnet schools, so I was entirely educated in the LA Unified School District Magnet System.
All of those things add up to me getting the opportunity to be exposed in the first place at an early age, which is something that I think about a lot. And since my parent spoke English, she had access to a lot of the media resources that people can get locked out of in a society that focuses on English as a primary language of discourse. So I think that some of it is personality, and some of it is just sheer luck of being born to the right mom.
On my mom's side of the family, for generations people have been teachers. My uncle was a teacher, and thought about things in terms of encouraging me and pedagogy. I think that's why he bought me the book. I do also think that that's part of it. If a kid never has the opportunity to get exposed to science, how are they going to get excited about it, right?
It's also the case that I was a good test-taker. I scored high on my standardized tests from first grade onward, and that meant I eventually got marked as highly gifted. It means that I got treated better at school. I had a couple instances of where I got thrown out of class by teachers. I never saw it happen to any white students, but it did happen to me a few times. But I didn't get sent to the principal's office, I got sent to the library. I think that's because I was a good test-taker, and overall was considered well-behaved.
I was also plugged into school. I liked going to school. That meant that my mind was open to the things I was being exposed to at school. I went to school briefly in London and got treated terribly by the teacher. I think part of that was because my reputation as a high performing student didn't follow me there. So the teacher just took me for whatever ideas she had about Americans or about kids who look like me or whatever. She treated me terribly, and I've never been so unplugged from school in my life as I was during that period in England. I do think that being treated well at school also helped create that opportunity for me to find what I was passionate about.
It may seem like I just keep posting stuff that says the same thing over and over because I'm looking for stuff that...
I want to ask about your experience in higher education. You've studied and researched at a variety of schools. Looking back, would you have handled your own education differently in any way?
My husband likes to ask me this question periodically. [Laughter] I think because I have a tendency to be very critical of how higher education is delivered, particularly in STEM, and particularly to people from marginalized communities. This is something that I think about a lot. I think if I had to go back in time, I would maybe have younger Chanda apply to some HBCUs (historically Black colleges and universities).
In particular, Spelman does a phenomenal job producing Black women who go on to Ph.D.'s in STEM. They're not given a lot of credit for that. They don't get awards for it. You don't hear President Obama coming and giving commencement speeches and thanking them for their service to the country—which it really is a service they provide—but they're one of the top three producers of Blacks who go on to Ph.D.'s in STEM.
Going to an HBCU can be a different experience for Black students. What I've read is that Black students come out of HBCUs with higher levels of self-confidence than ones who go to predominately white institutions. So when I'm talking to Black high school students who are interested in going on to do STEM, that is something that I tell them about, that there are some significant advantages to going to HBCUs. I believe one third of the physics majors in the United States who are Black are produced by HBCUs. That's actually fairly recent, it used to be over half of them were. That's actually a change that's just happened in the last 10 years.
So they really are providing a service to the country that I think goes unrecognized. I needed a full ride to college, so when I was applying to college, I applied to twelve schools. I got into all of them. Five of them were University of California campuses. I couldn't afford any of the public universities that I got into. I could only afford Harvard College, the California Institute of Technology, and Carlton College. Of the three, Harvard seemed like the best choice for a Black student in terms of access, being part of Black student community and being in an urban area. So that ended up being the major determining factor for me.
Harvard is among the most prestigious schools in the country. How did you find your experience there?
When I got into Harvard and was making my commitment, my college counselor Elaine Berman—who I'm still good friends with—she said to me, "I don't think that you have the ego for it." I was really mad at her when she said it. I was like, "What do you mean I don't have the ego?" I was confident I was going to get into Harvard, so that seems pretty egotistical. [Laughter]
It took me until years after I graduated to really realize what she meant, which is that I'm not a very competitive person. I'm competitive with myself, but I don't mind other people doing well. I actually really want everybody to do well. I want everybody to have the chance to do well.
For me, I experienced Harvard as a very competitive environment. I was shocked by the number of legacies that were in my class, the number of people who had been recruited primarily as athletes and didn't have the same kind of academic credentials that I felt I had to have in order to get in. So in that sense, for me, it was a major disappointment because I thought it was going to be this community of people who were just really nerdy and really passionate about intellectual stuff. It was a lot more complicated than that.
There were people there like that, but there were also a lot of people there who were far less interesting than people I went to high school with who didn't get in, but who had parents who were both doctors and had been able to buy them the best possible education in the best possible school, and also send them to repeated SAT tutorials. I trained myself for the SAT, right? So I think there was some element of disappointment when I realized how much of intelligence can be bought.
In particular, the physics department was not a fun place. I think it was especially not a fun place to be a Black woman. It was not a fun place to be someone who had gone to a public school that was good, but didn't have preparation for the level that Harvard expected physics majors to come in with. If you hadn't had a really good AP physics class, the physics program wasn't really for you—that was kind of the ethos. I had taken AP physics independent study. I'd only gotten through about half the material because I was teaching myself. I think it was a challenge for me, and I noticed that a lot of people who were like me ended up dropping out of the physics major even though they had been excited to major in physics when they arrived.
That said, I had an office mate my first year of graduate school who was completely the opposite of me in a lot of demographic ways. She came from an upper middle class household, had gone to a very nice public school in a rich neighborhood in the Bay Area, had had all of the preparation, and she still found the physics department to be an unhappy place.
I didn't know if the thing that we had in common there, the running current, was that we were both women. I did know that the physics department has made changes, and I think is working on becoming a more welcoming place. But now that I'm at MIT where 50 percent of our undergraduate majors are female. I think that at Harvard it's still about 25 percent in the physics department.
For me that raises a red flag; what's going on over there? That said, some of my best friends are Harvard physics professors. I have one coming to my house on Friday. He was also not on the faculty when I was an undergraduate, and I think someone like him could have been a game changer for me. So some of it is the point in time when you land there.
When I got to Harvard, there were only two women faculty in the physics department. I think there are something like eight now. They're going through some culture change, but I think for me, it was a pretty unpleasant culture. And I should say that the astronomy department at Harvard was the complete opposite. I had a very, very different experience in astronomy. I was a double major, and it was just like night and day.
And you should be allowed to attend pool parties, peacefully. <3
What was running through your head when you tweeted about the number of Black American women with physics Ph.D.'s? What do you feel about that statistic?
How did I feel when I posted that? You know, whenever I think about these numbers—and I guess this makes me some white supremacist stereotype or whatever—I feel angry. I feel really, really angry. When I started as a physics major, I understood that I would be some kind of barrier-breaker, but I didn't really understand what that was going to feel like, or how hard it would be and how upsetting it would be, and how difficult it would be to watch other people go through the same process. So I think I felt angry; I felt like people need to hear this. People need to know this.
In particular, in the astronomy community. I have two degrees in physics and two degrees in astronomy. There's a lot of discussion about women in astronomy. For decades, this discussion about women in astronomy has centered essentially on white women. They don't say white women, but when the statistics are trotted out, they don't disaggregate for race. The trends for underrepresented minority women, Asian-American women, and white women are different. Because white women are a much larger number, they dominate overall trends for the word "women".
I have struggled to get people within the astronomy community to understand that. It has involved some really ugly discussions sometimes. I remember when I was planning with a delegation of women in astronomy to go to the White House to talk to Tina Tchen, who at that point was the head of the White House Council on Women and Girls. I said, "We should really make a point of saying something about the experiences of women of color and people who live in the double binds. A white woman who is a well-known advocate for women in astronomy turn to me and said, "I know that that stuff is really important to you, but we need to focus on things that matter to everybody else."
Now, this is someone who's known for being supportive in the community. Another example was: I'm trying to get people who do collect the data—like the American Institute of Physics, they have a statistics team—and we wanted to talk about the importance on surveys of women about asking about their race. In one conversation, an advisor who was a scientist at one of the top five institutions in the country, she said, "Well, I don’t really see what my race has to do with anything."
It was like, "Of course you don’t, which is kind of the point." We need to ask about race because there are lots of women who do feel that way about it. So, it's very hard to have people regularly and repeatedly remind you that your experiences are invisible, that they don't matter, that nobody has noticed in any serious way until recently when diversity has become kind of en vogue, that there are no Black women—like anywhere. We're a rarity and that also means that we're incredibly precious, in my opinion.
The United States, the federal government, has spent an extraordinary sum of money educating me. The Pell Grant, I was an NSF research fellow, which is prestigious and expensive. They spent hundreds of thousands of dollars on me and I am a rarity. I'm the only Black woman in theoretical physics.
I say this about me because I can talk about it for myself. But it applies to every single Black woman who gets her foot into the door and gets that far—gets a master's degree, gets a Ph.D. Part of what I wanted to say to people with that tweet is: Each of us is special right now. We are barrier breakers, and I do think that the community has a responsibility to promote our success in a very particular way because it is hard to produce one of us.
Let's help this Black woman (a real one!) to Fisk-Vanderbilt to start graduate school in physics this fall!
You're deeply invested in both your science and your activism. How do you pull that off logistically? How does that come together?
I have to give my husband an enormous amount of credit. Without my husband, a lot of the stuff I get done would not get done in the way that it does. My husband does all of the cooking. He makes sure that I don't just eat a banana and yogurt and chocolate and milk for dinner. [Laughter]
I have to give him a lot of credit for being willing to take care of things like that. He travels with me as often as possible. When I went out for a job interview, he went with me and ironed my clothing, and he practiced my talk repeatedly, and gave me feedback, and held my hand when I stopped and cried because I was stressed out. That's a really key element of me being able to pull off everything that I do.
At the same time, I also want to say that I recognize that it's problematic that to be somewhat successful and be able to be an activist and advocate for myself and for people like me and for people not like me, it kind of requires this second person who's functioning in a supportive way. I honestly think that, when we talk about the great theoretical physicists and the 20th century as this great century for science, that not enough credit is given to the many, many, many stay-at-home wives and caretakers who ran the house, so that professors never had to think about it and could just think about physics.
People don't appreciate that that is an element of how physics has gotten done, particularly over the last century. Something that a lot of people don't know is that, until fairly recently, we actually didn't even type our own dissertations. There's an administrator in the Harvard physics department, Carol Davis, who's been an enormous support for me. She was the only Black adult I saw on a regular basis in college. For decades, she typed people's Ph.D dissertations.
Sometimes she received hand-written notes. Sometimes people would hand her a draft, and then she made them look nice. She would retype it. I think that not enough credit is given to people like Carol for being an integral part of the process of getting science done. When I got to my office, my garbage can is empty because there is a wonderful woman named Phillis who comes in and empties my garbage can everyday so that my office isn't overflowing with garbage.
All of these people around us, who are making sure that our working environment and our home environment function so that we can get work done, are part of the scientific process—and part of the activist process, in my case. So, I have to give them credit for that.
Also, I don't have kids. I actively made a choice that my contribution to the world, at least at this point, is going to be through advocating for people who are not necessarily my biological children or my adopted children. If I did have kids, I would probably adopt.
But I am not willing to give up the activism that I do, to do the hard work of raising a child, which I think is maybe the most important job on the planet—raising children, having children, whether they're biological or not. That was an active choice that I made and not just something that it hasn't happened yet.
We ask people about living a fulfilling, satisfying life. Have you had any recent realizations about living a rewarding life?
I will say that I am a very hardcore Pilates practitioner. Over the last couple of years, I've really been forced to recognize that I can't sacrifice my Pilates practice on the altar of my academic career or my activism—that I can't not do it just because I feel like my time would be better spent doing something else. Part of that is that I was in a car accident when I was 19, and Pilates controls the chronic pain that I have from it. My body kind of demands it.
The thing that really dawned on me over the last two years is that it's not just my body that's demanding it, but really my mind. I was able to focus better on my physics when I was able to make sure that I had a regular Pilates practice. I go for one-on-one lessons, two times a week. I have equipment at home.
I think making sure that I remain engaged with my Jewish identity, and particularly the rituals of lighting the Shabbat candles and so forth. I think understanding that all things can't be sacrificed on the altar of academic career and physics has been really important, and understanding that that balance is not just for my own sake, but is in fact really in some sense in service of doing the physics. I can't just sit around feeling angry about the number of Black women, or worrying a lot about dark matter. I also have to allow myself to do these other things.
I do think that the attitude in the physics community can be, "Well, if you're doing something else with your time, it clearly shows that you're not committed, and that you're not a genius—like Einstein-level genius—because Einstein just worked really hard and thought about things." But in fact Einstein was a polymath. He was interested in a lot of things. So I've been working on allowing myself to be interested in the many things that I am interested in, and not feel guilty about it.
I do think the way the academic job market works—it discourages people from being whole, and that's a major problem. I think it disproportionally impacts people from marginalized backgrounds because we already have to work so hard to feel whole, to supplement the feedback we get from society that sometimes makes us feel diminished with self-love and community love. Physics is not necessarily the place to get that self-love and community love.
You were quoted a few months ago in the Chronicle of Higher Education. After Ferguson, you said you basically asked yourself, Who cares about theoretical astrophysics when black people are getting shot left and right? But the story didn't explain how you ended up answering that question for yourself. What was your answer?
I wasn't very happy with the framing of that article. I think that the angle the article took maybe gives what I said a different context than the one I intended for it.
I don't question the value of my Ph.D. at all. I question whether society values my life. My cousin told me that he and his wife are having a baby, and I question whether society values that baby. In some sense, it's not that I question the value of my Ph.D., but I question a society that maybe doesn't value my life, and therefore doesn't value my mind, and doesn't value my Ph.D.
I don't think that because I have a Ph.D., I'm in some upper echelon of society. I actually have a major problem with the elitism and the classism that goes on in academia. I think everyone has something to contribute. Everyone is precious in their own way. But I think it's obvious that, structurally, American society has a persistent problem with recognizing not just Black people, but Black people as human beings who are just as deserving of the opportunity to think about big picture questions.
There's been a lot of research recently, and in particular there was a study by Kenny Gibbs Jr. and some other people about why underrepresented minorities choose the area of science that they go into. One of things that they emphasize is that minorities like to choose fields where they think that they will be helping people.
I think it's great to want to help people, and it's certainly the case that when I was thinking about doing theoretical physics, I had this wild idea that if we could understand how the universe worked and what the fundamental principles of operation of the universe were, that this could somehow help humanity end up in a better place—that we could derive some ideas or principles of peace from that. I was a very idealistic teenager I guess.
Even when thinking about cosmology, I felt, I'm going into a field where I'm going to help people because cosmologists are dreamers, and cosmology is also something that humans have done since they were really able to look up at the sky and have thoughts about it.
But I do think that there is a pressure when psychosocial resources and physical and fiscal resources are scarce. That when we have a success, that that success has to be fed back into the community. So it's easy to understand why people think, "I'm going to be a doctor," or "I'm going to be a researcher that thinks about Sickle-cell"—"I'm going to think about Black women's mental health"—because these are all things that have not been thought about enough, or problems that haven't been solved. But my dream is for Black children, and Native American children, and Latino children, and Asian children to be able to make the choices that White children seem to sometimes be able to make, which is that, "I'm going to think about this because it interests me." Not because, "I owe it to the community." Not because, "I see this problem in my community that doesn't get solved because of the color of our skin, so I'm going to try and solve it." But for them to say, "Hey, dark matter's a weird thing. Why don't I think about that?" I want everybody to have that equal opportunity to dream, and dream big, and not dream in the context of the duress of racism, and transphobia, and a host of other things.
I understand that I don't live in that society, and I understand that to make sure that some generation lives in that society will require more than just doing theoretical physics. But I hope one day that that's not the case for people like me anymore.
In addition to, or other than, Stephen Hawking's book, is there a book or handful of books that have had a profound impact either on the course of your life or your intellectual development?
I would say Carl Sagan's "Cosmos" is probably number two, and in some sense competitive for number one with "A Brief History of Time." I had such a hard freshmen year at Harvard that I was ready to drop out of the physics major because I was feeling pretty discouraged. Over the summer, I had a couple of really helpful experiences. One, I had a research supervisor at the University of Chicago, Henry Frisch, who was really encouraging. But also, I read "Cosmos" the summer after my freshmen year, and Carl Sagan had a beautiful perspective on what humanity's relationship to science was.
He really saw science as a humanitarian enterprise in some sense, and a shared human enterprise—not something that just people with Ph.D.'s in some rarified environment—but really something that we collectively, as a human community, have been doing together for millennia. That had a profound effect on the way that I thought about science. It said to me that people like me did do science.
I think that that was a major point in "Cosmos"—that it was human enterprise. It wasn't a White European post-Enlightenment enterprise. It was a human enterprise. It really changed the way that I think about things. I would say Carl Sagan is probably my biggest influence in terms of how I think about science and society.
Can you share some research you've worked on recently that you're particularly passionate about?
My area of expertise is theoretical cosmology. I think about the evolution of the universe, the beginning of the universe (if it had a beginning). Right now, I'm thinking a lot about dark matter, and about what happened in the universe during the first second after whatever came before.
Something that I'm pretty excited about right now is a dark matter candidate, which is a hypothesized particle—so it's never been detected—called the axion. We're still trying to understand, if the axion is the dark matter—how would it behave both in the early universe and now in the time period that we are living in? What kind of structures would it form, et cetera?
I'm pretty excited about the axion; it was actually originally conceived of to solve a problem in particle physics that had nothing to do with cosmology. So if we do detect the axion—and there are active searches; there's an experiment called ADMX at the University of Washington, for example, that is looking for axions—if we were to find it, it would be a really big deal for multiple fields in physics. It's a very exciting thing to think about.
Is there a significant recent discovery or new understanding in physics that is not yet widely known outside of academia, but might be common knowledge in the years to come?
I guess for me, "A Brief History of Time" is really the marker. What's in "A Brief History of Time" that needs to be updated?
Looking forward, the Large Hadron Collider is turning back on this year. I think that if we find evidence for a symmetry called "super symmetry," that would be an extraordinary thing. I think in 10 years, super symmetry will be something—we will have to update "A Brief History of Time" for the first time in a very serious way.
Then I'm always hopeful that we're going to figure something out relating to the dark energy and dark matter problem. Really, in a lot of ways, cosmology has made extraordinary strides in understanding what we already understood, in greater detail. But there's a lot that we haven't made much progress on, in the last 30 or 40 years.
I'm hoping that some fresh young minds will make some contributions to it, and that maybe I'll have the opportunity to make some contributions to those questions. But again, I think our culture of homogeneity in physics is maybe starting to harm the mission.
"This list focuses on people who self-identify as Black in the way it is usually used by North Americans of Black African descent. There is a fairly complicated discourse about how this Blackness connects with how people in the African diaspora outside of North America, the Caribbean and UK use the term "Black." Here we mean "people of African diaspora descent" but in my experience, many people from the continent of Africa mean something different when they say "Black." (For example, I often don't count, and Trevor Noah talks in a documentary about how complicated things are for him in terms of identity in South Africa.) I might later expand to include people of African descent more globally but gathering names for that will include a lot more legwork and will probably fall under a different moniker for the reasons discussed above. And of course, in Australia, Aboriginal people use "Black" to self-identify and are not of African descent."