Dr. Lindley Winslow is an Assistant Professor of Physics and nuclear cosmologist at MIT. She received her BA in Astrophysics & Physics, Masters in Physics & Ph.D. in Physics from UC Berkely. After graduating, she worked at UCLA before moving to MIT.
1. In layperson’s terms, explain what you do.
I build detectors to try to measure the basic properties of particles. In other words, I try to measure the impossible. The main focus of my whole group at the moment is the search for the process called neutrinoless double beta decay. One of the open questions about the neutrino is whether it is its own antiparticle. The neutrino is one of the fundamental particles, we think it’s not made up of anything else, and it only interacts via weak interactions so it is very hard to detect them! They hold no electric charge so nothing stops them from being their own antiparticle. The question is- Is it really its own antiparticle? The only way we can find out is by observing a process called neutrinoless double beta decay. What this process is – is when some nuclei decay it is energetically forbidden for them to eject one electron, so they eject two electrons. To preserve lepton number, they also have to eject 2 neutrinos to balance everything out. This process, also known as double beta decay, is one of the slowest process observed and has a half-life on the order of 10e20 years. We have seen this and we know it happens; but, we want to observe double beta decay happen without the neutrinos. If no new neutrinos come out what effectively happens is they turned into their own antiparticle and got sucked back into the reaction. Theoretically, this can occur in a particular isotope of Tellurium Dioxide. This decay is also very slow (current best limits on this reaction are about 10e26 years) and we would like to do better than that which requires instrumenting a ton of this. One way of detecting neutrino-less double beta decay is getting a tank of liquid and dissolving the isotope in the liquid. The way that type of detector works is if a charged particle, like the electrons ejected, moves through, like the electrons ejected in the decay, it gives off light and you detect that light. This method is simple but works very well and is easy to build. Another method of detection we are investigating uses crystals made of this isotope. We take the crystal and we attach a very sensitive thermometer to it and then cool them both down to ten millikelvin. For reference, the universe is about 2.7 Kelvin! At that temperature range, you can see the increase in temperature of the crystal when a charged particle goes through it. We aren’t sure which one will work better but they are complementary in their approach. The reason this is important is according to the laws of physics there should be equal amounts of matter and antimatter. The issue is we don’t see any antimatter, in fact, it is one part in 1,000,000,000. This is where neutrinos come in. Neutrinoless double beta decay creates more leptons than anti leptons. It is a way to generate more matter, and that is what we are desperately looking for. The fact that the neutrino is its own antiparticle will stop breaking the lepton number symmetry and the matter – antimatter symmetry. Once we know this, we can open up room for more theories about the early universe, and how what we see today came about.
2. Why did you become a scientist?
It is one of those things that came together. I had always had an interest in the science I learned in high school. I actually didn’t take physics until my senior year but had always been interested in the stars. I went to Berkley with the intention to be an astrophysics major but I ended up becoming a physics & astrophysics, double major. You take lots of physics to become an astronomer. In fact, the curricula overlap until junior year. At that point, I had started doing research with a lab that did particle astrophysics and I really liked it. I liked building things. I liked getting to do kind of everything. I got to build things, I get to analyze the data, and I got to think about the consequences.
3. What is your favorite aspect of your work?
I like the fact that it is never the same thing. From day to day I can do something different. As much as I love physics I think I would actually be bored as more of a theoretical physicist just thinking about physics every single day! What I get to do from day to day is I get to learn new things. I get to work on different parts of my experiment from coding to writing up news blurbs on my experiment to working with engineers on how to better construct and execute my experiments.
4. What does being a scientist mean to you?
To me, it means never stopping learning. The quest is always for more knowledge and that means you are never secure in the knowledge you already have.
5. What has been your greatest failure, and what have you learned from it?
That’s the interesting thing, you always learn from failures. My biggest failure was when I was a grad student. We were trying to refurbish some old detectors and I hadn’t asked in advance how old they were. It turned out they were older than I was at the time. I tried to get them to work, and all the wires kept breaking and I spent a lot of time trying to fix them. I should have just given up. They weren’t in a position to be refurbished. It also taught me an important lesson that equipment that is free is worth every penny. In fact, it will probably cost more than that in new parts and time.
6. What has been your greatest achievement in your career?
I’m an assistant professor so I’m on that hill of trying to get an experiment of my own creation working. To see it incrementally - As a post doc, I worked with working on nanocrystals and using them to observe double beta decay. With one undergraduate we wrote the paper on how these crystals work, how well they work, and in the future, how observing neutrino-less double beta decay could work. I then began to run simulations at UCLA looking at how fast the photodetectors would work, how we could improve the nanocrystals. Then I wrote a paper on that, and a proposal. I got funding which was very exciting. Now we are at the point where we are writing the schematics for the detector. In detail, we are explaining how each component must work from electronics to how the photodetectors are being held up. I think we are 75% of the way there. My greatest achievement hasn’t arrived yet but it has been 5 years in the making. Hopefully, in a year and a half, I’ll be able to say I observed neutrino-less double beta decay.
7. What has been the biggest change you have witnessed in your field of science?
It happened right as I was starting Grad school. By that I mean on the day I started grad school an experiment trying to determine how many neutrinos came from the sun released their first results. To give some context, sometime before, another group tried to figure out the same thing and they only detected approximately 50% of the predicted number of neutrinos. Scientists decided that they just didn’t understand how the sun works or that the detectors were faulty. So from the 60’s to the 2000’s scientists revised the solar model, and the detectors and got similar results. The questions changed to “is the neutrino doing what we think it is? Does it if have mass?” If the neutrino had mass, it could perform the phenomenon called oscillation that would allow it to decay into different ‘flavors’ of neutrino. So back to the experimental results released on my first day of grad school. What they saw was if you measure one ‘flavor’ of neutrinos you got this 50% number. If you measure all ‘flavors’ of neutrinos you got the right answer. This was awesome as it said that the electron ‘flavor’ of neutrino morphed into other ‘flavors’ as they came to earth proving that they have mass. This fundamental fact has opened a lot of new questions in physics and helped steer me towards my thesis project, and work in general.
8. How do you think your field will change in 10 years?
What I do is big science. The next step up from me are international collaborations of thousands of physicists working together on one problem. The big result that we hoped would come out of the LHC didn’t really happen so we as a field are moving back to the drawing board. We are moving back down from everyone working on one thing to everyone trying new ideas out. We are very aware of the fact that it is a gift to study what we study, and that we do not waste our money, and we have the motivation to get together large groups of people. I think there will be a regrouping to try and figure out what the next steps are. I think that many of those next steps will be space based.
9. What motivates you?
It depends on the day. My big motivation is curiosity. These are basic questions I’m asking. They are the ones you ask as a small child and your parents can't give you good answers too, but they are also the ones we have been asking since the moment we could. I would love to make a contribution to our understanding of how the universe came about. On a day to day basis, I love teaching students. I spend some time teaching into to E & M but I spend more time teaching the students who work in my lab how to be scientists. That’s very rewarding too.
10. How do you define success?
Getting a number with an error – that is success in my field!
11. What one discovery in science do you most admire and why?
I’m going to be completely selfish and go with the discovery of neutrino oscillations, especially the KamLAND result This was the experiment I did my thesis on. My graduate advisor took a big risk. He built a large detector worth millions of dollars. At the time people thought you could only detect neutrinos at one particular angle, and he chose to build his detector at a different angle - the large mixing angle. He took this risk, and he was right! It taught me to make sure to not get caught up in group think, and how to manage and organize large, international teams.
12. What are the greatest challenges facing humans today?
The biggest challenge is harnessing the technology we have invented in the last 50 years. We have all the tools we need to solve most of our problems. Now it is the question of using them correctly.
13. What one book do you recommend everyone read?
Pride and Prejudice by Jane Austen. There is a reason we keep reading the classics. There is just so much truth in them.
13. What is your favorite movie?
The original Star Wars Trilogy
14. What is the best piece of advice you have received?
My thesis advisor told me to come work for him & he turned out to be right!
15. If you could have dinner with anyone alive or dead, who would you choose?
Maria Goeppert Mayer. She discovered the nuclear shell model and wrote down the underlying theory of my work in the 30’s. She also won the Nobel Prize in Physics in 1963. I think she is the first of the modern female physicists. She has an interesting story as well having grown up escaping Europe. She wasn’t able to get a job at the University of Chicago due to nepotism rules even though she was about to win a Nobel prize! While I was at UCLA, I met a woman who was working in physics around the same time as Mayer and she told me a great story about her. She asked Mayer if she had ever gotten bitter. Mayer said “Almost”. She just sounds like such an awesome lady
16. What question did I not ask you that you want to answer and share with the readers?
The message I really want to get across is that you don’t need to be a genius to be a scientist. You need to want to do it. There is the image of the lone genius but that isn’t true! You need some level of competency but hard work matters a lot more. I would say to be a successful scientist you need 20% natural talent and 80% hard work. All too often people think that balance is flipped.
17. If you could go back in time what advice would you give your high school self?
I love being a scientist but I don’t think I understood all the awesome things I could do. I don’t think I understood all the wonderful things I could do an engineer. On a more subtle note, when I was in high school, I thought the only way to make the world tangibly better would be by being a doctor. There is so much in science and technology that can help people. I don’t think I had a big enough picture of the possible impact of science and engineering.
18. What would you say are the top three skills needed to be a successful scientist?
- Perseverance or grit
- The ability to learn new skills
- An enjoyment of maths and science
19. How would you say your gender has impacted your experience as a physicist?
I’m lucky that I’m in the generation that isn’t as blatant. I was never confronted with very overt sexual assault. There are times that I can definitely tell that I’m a woman, and our gender norms dictate how assertive I can be and whether I’m listened to. It can be frustrating when I know my gender is getting in the way. I have also had opportunities that come my way because of my gender. It is more along the lines that if you are the only woman, people know who you are. That’s a bit of a double-edged sword. If I’m an idiot, everyone knows I’m an idiot, if I did something good, everyone knows I did something good.
If you have any more questions, or would like to reach out to Dr. Winslow, her email is email@example.com