A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.
“How can something so tiny like a black hole influence the entire galaxy itself? The belief now is that they know how to talk to one another.” — Luis Ho.CreditGilles Sabrie for The New York Times
Black holes. I was one of the first people to show how common they are. This was one of the results of my doctoral thesis in 1995. Before, the thinking was that they should exist but that they were really very rare. I was able to demonstrate that every big galaxy has a nucleus containing supermassive black holes. This was suspected before, but I was able to prove it.
How did you accomplish that?
By searching for an indirect way to show their existence. I looked for signs of energy, and what I found was that basically every galaxy had a black hole. We just hadn’t seen it before.
After I finished my doctorate, the Hubble Space Telescope was repaired. It made it possible to measure the rotation speed of the stars and gas around those black holes. The Hubble confirmed many of the points of my thesis.
How central are black holes to understanding what the universe looks like?
We’re learning they are to be considered to be one of the key ingredients that make galaxies look the way they do. The big question is, how can something so tiny like a black hole influence the entire galaxy itself? The belief now is that they know how to talk to one another.
A. In Mozambique, which during that time was still a colony of Portugal. In the Africa of my childhood, there was a clash of backgrounds. The Portuguese were not very accepting. There were many outward expressions of racism. Then, in the late 1970s, after the country became independent and essentially deteriorated into a very ugly civil war, we were forced to leave. They confiscated all my father’s properties. We left with our suitcases.
Where did you go?
By a stroke of good fortune, we somehow got visas for the U.S., so to East Boston. I was 12, the only Asian in a very rough school. My father washed dishes. At school, people made fun of me. That made me determined to learn English quickly enough to get into a better school, which I did. I got into the best one in the city, the Boston Latin School. From there I went to Harvard, where it seemed as if I was the only person who wasn’t rich and worked. It felt like wherever I went I was the outsider.
When did that end for you?
One day at Harvard, I stumbled into a lecture about the black holes in the Milky Way. I was absolutely captivated. I sought out the lecturer, Paul Ho [no relation], and he immediately gave me a research project.
One of the things I loved about astronomy was that it was not tied to the mundane. It was not even tied to our planet. Maybe this was a reaction against all the day-to-day things my family had to struggle with.
What area of astronomy did you work in?An Earthling’s Guide to Black Holes
We are living in an era of tremendous breakthroughs in our knowledge of the universe. Why are we learning so much now?
A lot of it is technology-driven. Astronomers have a lot of very nice new toys. The rapid development of astronomy is completely tied to access to big telescopes. That’s one reason why I urged China’s leaders to partner on one of the big new international telescopes.
China has great scientific ambitions. It’s an unwritten rule that to be part of the astronomy club, you need to be part of a big telescope. It wasn’t an easy sell. The three new telescopes that were coming were all to be on foreign soil, and that was a difficult concept. They eventually choose to join with Caltech, the University of California, Canada and India on theThirty Meter Telescope.
When you were growing up, did you ever think you’d come to live and work in China?
Not ever. One of the things that influenced me was meeting so many talented young Chinese scientists. I helped some get into American universities. I could relate to their struggles here. When they returned to China, it wasn’t always possible for them to succeed. There was a mismatch between their talents and opportunities.
Over the past decade, things have begun to change. China has made large science investments, and these people now have something to go back to. In 2013, when the Kavli people approached me, I felt I might have something to contribute to an environment like that.
What appealed to you about the foundation’s offer?
It actually was very unappealing. It came at the worst possible moment. My wife and I had just had a baby. There were older kids in high school. They could not be uprooted. The job meant living in Beijing, with its pollution, traffic and cramped apartments. My wife, who stayed behind, said, “We’ll just have to make it happen.” My wife didn’t want me to lose this opportunity.
It involves a lot of juggling. To save commuting time, I sleep at my Peking University office. I get up at 5 a.m. to Skype my daughter. I tutor my son via the Internet.
I return to California every two months to see them.
Chinese education has a reputation for being mechanistic and rigid. Have you found it that way?
They had a very rigid system because, in a different time, that’s what worked.
I know what made Carnegie an effective center for astronomy research. It was an environment that allowed a lot of free discussion and brainstorming. I’m trying to bring some of that to our institute in China.
My dream is that 20 years from now, the best students from Harvard and Princeton will want to go to Peking University, not the reverse. What my institute can do is provide an oasis where I can expedite the process, because I have more control over this little patch.
I think the Chinese system can evolve, and Kavli is providing one model. We have nonhierarchical interactive discussions. We’ve attracted very high-level visitors to lecture and teach. Already, our Kavli Institute attracts many non-Chinese postdocs, and they want to come here because they see the ferment.
The other thing is that China now has the means to invest in science. And it is willing to do so! Even in the most advanced countries, basic astronomy is a hobby science. Yet in China they are willing to spend on it. With that and these great human resources, the trick is to combine them.
After a lifetime of travel and displacement, do you feel at home in Beijing?
That’s where I hope I can find a home. That’s why I work so hard to make the program successful. I am there for the long haul. I’ve been learning to speak and write the language. Funny thing: The last time I returned I actually missed the place. A year ago, it was the most alien place to me.
1. A theoreticalobject in space,themass of which is so greatanddensethatnothing,notevenlight,canescapeitsgravitationalpull.Blackholeshavealwaysfascinatedme. If evenlightcan'tescapethem,whoknowswhattheymightreallycontain?
2. Anyplace,region, or thing in whichsomething(items,people,etc.)areirretrievablylost.My desk is just a blackholeof papersandthings,and I canneverfindanything in it!Alzheimer's is a terribledisease,like a blackhole in one'smind.
3. A prisoncell or area of confinement,especiallythatwhich is in notoriouslypoor or hostilecondition.Refersspecifically to theso-called"BlackHole of Calcutta," a prison in WestBengalwhere, in 1756,146Europeansweresaid to havebeenimprisonedandallbut 23 suffocatedovernight.Sebastianwassentenced to 30 days of solitaryconfinement in a tinyblackhole,wheretheonlylightcamefromtheslotforhisfood.
1. A wretchedprisoncell or otherplace of confinement.Forexample,Thepunishment is solitaryconfinement,knownas theblackhole. Thistermacquireditsmeaning in 1756withtheeventknown as theBlackHole of Calcutta. On thenight of June20,theruler of Bengalconfined146Europeans in a prisonspace of only 14 by 18 feet. By morningallbut 23 of themhadsuffocated to death.Althoughhistorianssincehavequestionedthetruth of thestory, it survives inthisusage.
2. A greatvoid or abyss.Forexample,Running a singlesmallnewspaper ad to launch a majorcampaign is useless; itamounts to throwingourmoneyinto a blackhole. Thisusagealludes to a region, so named by astronomers,whosegravitationalfield is so intensethat no electromagneticradiationcanescapefromit.[Late1970s]
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