Learn about Mauna Kea and how the pursuit of knowledge can be harmful. Plus: the smallest measurement of gravity ever. Additional resources from Dr. Chanda Prescod-Weinstein: Pick up "The Disordered Cosmos: A Journey into Dark Matter, Spacetime, & Dreams Deferred" on Amazon: https://amzn.to/32JjzDu Website: http://www.cprescodweinstein.com/ Twitter: https://twitter.com/IBJIYONGI Learn more about Mauna Kea: Pu’uhuluhulu, P. o. (2020). Pu’uhonua o Pu’uhuluhulu. https://www.puuhuluhulu.com/ TMT International Observatory. (2020). TIO. https://www.tmt.org/ United States Public Law 103-150, informally known as the Apology Resolution: https://www.govinfo.gov/content/pkg/STATUTE-107/pdf/STATUTE-107-Pg1510.pdf Maunakea and TMT misinformation fact check | University of Hawaii System. (2021). Hawaii.edu. https://www.hawaii.edu/maunakea-stewardship/maunakea-tmt-fact-check/ Scientists captured the smallest measurement of gravity on record by Briana Brownell Rothleitner, C. (2021). Ultra-weak gravitational field detected. Nature, 591(7849), 209–210. https://doi.org/10.1038/d41586-021-00591-1 Westphal, T., Hepach, H., Pfaff, J., & Aspelmeyer, M. (2021). Measurement of gravitational coupling between millimetre-sized masses. Nature, 591(7849), 225–228. https://doi.org/10.1038/s41586-021-03250-7 Lewis, G. (2016, February 12). Timeline: the history of gravity. The Conversation. https://theconversation.com/timeline-the-history-of-gravity-54528 Subscribe to Curiosity Daily to learn something new every day with Cody Gough and Ashley Hamer. You can also listen to our podcast as part of your Alexa Flash Briefing; Amazon smart speakers users, click/tap “enable” here: https://www.amazon.com/Curiosity-com-Curiosity-Daily-from/dp/B07CP17DJY
Learn about Mauna Kea and how the pursuit of knowledge can be harmful. Plus: the smallest measurement of gravity ever.
Additional resources from Dr. Chanda Prescod-Weinstein:
Learn more about Mauna Kea:
Scientists captured the smallest measurement of gravity on record by Briana Brownell
Subscribe to Curiosity Daily to learn something new every day with Cody Gough and Ashley Hamer. You can also listen to our podcast as part of your Alexa Flash Briefing; Amazon smart speakers users, click/tap “enable” here: https://www.amazon.com/Curiosity-com-Curiosity-Daily-from/dp/B07CP17DJY
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/when-the-pursuit-of-knowledge-goes-wrong-w-physicist-dr-chanda-prescod-weinstein
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about how the pursuit of knowledge can sometimes get in the way of other human endeavors, with help from Dr. Chanda Prescod-Weinstein [(hard ch) CHOHN-duh PRESS-cod WINE-stine]). Then, you’ll learn about how scientists captured the smallest amount of gravity ever recorded.
CODY: Let’s satisfy some curiosity.
Science is an important thing. But it's not always the most important thing. Sometimes, science gets in the way. Take the fight going on right now on Mauna Kea [KAY-ah], Hawaii's highest peak. Astronomers want to build a thirty-meter telescope on the land. Indigenous Hawaiians regard that land as sacred. Our guest today is going to explain why conflicts like these aren't a simple matter of science vs. anti-science — they ask deep questions about our most vital priorities. Dr. Chanda Prescod-Weinstein [(hard ch) CHOHN-duh PRESS-cod WINE-stine]) is an assistant professor of physics and astronomy and core faculty in women's and gender studies at the University of New Hampshire. She's also the author of the new book, "The Disordered Cosmos: A Journey into Dark Matter, Spacetime, & Dreams Deferred." And Ashley asked her whether the pursuit of knowledge ever gets in the way of people's pursuit of everything else.
[CLIP 4:38]
We’ll talk more about Mauna Kea at the end of today’s episode. But hopefully the idea of “whose stories matter?” can help you think about lots of different issues in a whole new way. Again, that was Dr. Chanda Prescod-Weinstein, an assistant professor of physics and astronomy and core faculty in women's and gender studies at the University of New Hampshire, and the author of the new book, "The Disordered Cosmos: A Journey into Dark Matter, Spacetime, & Dreams Deferred." You can find a link to pick it up in the show notes.
A team of Austrian scientists measured the gravitational field of the tiniest object yet: a gold ball just one millimeter across. And this is a really big deal.
Scientists have been studying gravity for a long time. Like, remember Newton? His theory of gravity in 1687 did an almost-perfect job of predicting the motion of the planets. But that theory didn’t really hold up for very big things. That’s where Einstein stepped in with the theory of general relativity. The predictions of general relativity are only different from Newton’s at that extreme end of the scale.
But as scientists make more observations of distant galaxies, they find the measurements don’t match up with either of these theories. Something else is going on. As a result, gravity is still an area of active research.
We know the least about how gravity works on a really small scale. One reason for this is theoretical and the other is practical.
We typically think of gravity as a pretty strong force. After all, it’s what keeps our feet on the ground -- literally.
But compared to the other three fundamental forces of nature, gravity is relatively wimpy. It’s 29 orders of magnitude weaker than the next-in-line. That’s 1 with 29 zeros. That contrast makes it especially hard to measure.
The practical reason is that the Earth is so massive that it affects our experiments.
This new experiment used an ingenious way to solve that problem. How did they do it? Using a torsion balance.
Imagine a bar with a ball at each end hanging horizontally from a vertical wire, precisely balanced on each side. The Earth’s enormous gravity pulls the wire so it’s exactly perpendicular to its gravitational field. That’s what cancels out Earth’s effect on the experiment.
Then, they put a test mass — usually another ball — near one of the ends. Gravity attracts the ball and the test mass. We can measure how the bar moves to figure out the gravitational field. These researchers used balls of only 92 milligrams in mass, equal to about five grains of rice. That’s the smallest mass ever used in this kind of experiment.
The observations were important building blocks in our knowledge about gravity. So far, gravity hasn’t been reconciled with the three other fundamental forces that govern the behavior of very small particles.
So the tiny gold balls the experimenters used? That’s a big deal. It meant scientists could study gravity on a really small scale - a scale close to the quantum scale, where the other three forces dominate.
So what happened? The results matched up with Newton’s predictions. Thanks to this trio of tiny gold balls, we now know that Newton’s theory of gravity holds, even at this small scale.
Let’s do a quick recap of what we learned today
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ASHLEY: Today’s last story was written by Briana Brownell.
CODY: Our managing editor is Ashley Hamer, who was also an audio editor on today’s episode.
ASHLEY: Our producer and audio editor is Cody Gough.
CODY: Join us again tomorrow and we’ll help you understand the GRAVITY of the situation… so you can learn something new in just a few minutes.
ASHLEY: And until then, stay curious!