Gender bias and gender inequality in academia have a long history. As a gathering place for the most cutting-edge ideas and technologies of mankind, women in academia often face various unnecessary dilemmas. To this end, the academic community has actively promoted equal rights in recent years and tried to eliminate various negative influences, but the road to gender equality is still a long way to go.
However, we see that even under many obstacles, many outstanding female scientists have been seen, making indelible contributions to the advancement of human science and technology, and have become a "she" force that must be faced. To that end, we've launched the "See Her" series to tell their stories.
This past April 12 is World Space Day. Sixty-one years ago, 27-year-old former Soviet cosmonaut Gagarin took the Vostok 1 spacecraft and launched into space orbit at 9:07 a.m. Moscow time on April 12, 1961, returning to the ground after flying around the earth for 108 minutes, completing the feat of humanity's first conquest of space and opening a new era of human exploration of space.
Gagarin Graph Source Network
The hymn of humanity is the hymn of courage
Although this series of feats before and after may be an indirect product of the Cold War arms race, self-manned spaceflight has become a reality, and the yearning for space for all mankind as a community of destiny has reached an unprecedented frenzy. As the ultimate mecca for exploration, space carries the courage and adventurous spirit of human beings, and has been given a strong romantic color in that era. Even if you are not familiar with the "ultimate answer to life, the universe and everything" in The Odyssey through the Galaxy, you must be impressed by "Space, the final frontier..." in Star Trek, or familiar with the exciting theme song of Star Wars.
Life, the Universe and Everything by Daugarland Adams
In 1968, Stanley Kubrick's film 2001: a Space Odyssey was released and is still considered the pinnacle of imagination, foresight and depth in science fiction films today. A young man from London saw it and then created "Space Oddity" the following year based on the title of the film, in which the fictional character "Major Tom" aroused the hearts of countless people, he is David Bowie. Nine days after the song's release, on July 16, 1969, Apollo 11 was launched, leading to Armstrong's famous quote on the moon: "This is a small step for me personally, but a big step for all mankind." ”
David Bowie knows
"Major Tom" sang when floating aimlessly in space: "Planet Earth is blue, and there's nothing I can do..." And since the Apollo moon landing, the progress of science and technology has changed from the early exploration and experimental nature of artificial satellites to later multi-purpose, long-life, low-cost, high-reliability practical satellites; from the international space station in low Earth orbit to the emergence of the space shuttle and even commercial. The development of human aerospace has made a qualitative leap to today, and its application has entered all aspects of everyone's life. Perhaps the most obvious of these is the positioning and navigation that we use every day. Whether you use AutoNavi or Baidu, the voice package you choose is Lin Chiling or Shen Teng, behind which are the GPS global positioning system of the United States, the Galileo satellite navigation system of Europe, the GLONAS global satellite navigation system of Russia, and most importantly, our country's own Beidou satellite navigation system.
Car navigation Pixabay
"The Big Dipper handle refers to,
It's the direction home."
When it comes to Beidou, we have to mention Xu Ying. As a researcher of the Institute of Optoelectronics of the Chinese Academy of Sciences and the deputy director of the Navigation Technology Research Office, Xu Ying has long been engaged in the construction of the Beidou satellite navigation system, with the completion of engineering tasks as the main line, and carried out systematic algorithm theory and engineering application research in satellite navigation and its enhancement technology. With all this, Xu Ying, as a "visionary", was successfully selected into the 2017 MIT Technology Review "35 People Under the Age of 35" China list.
Xu Ying Xu Ying
After experiencing the application of the second generation of Beidou and the first launch of the third generation of Beidou networking satellites, Xu Ying always seems to have endless words when talking about Beidou. She once said that as a "rising star", Beidou has one of the biggest advantages over gps and other systems is its short message service, the development to today, Beidou has been the world's only global short message can provide global short messages and China's surrounding large capacity high concurrent short message communication global satellite navigation system, can provide emergency communication in areas where mobile communication signals can not be covered or in the case of serious damage to communication base stations. Starting from the short message system of Beidou-1 supporting the emergency communication during the Wenchuan earthquake in 2008, Beidou-2 and No. 3 retained this feature and greatly optimized it, and the communication capability was greatly improved. For example, when fishermen using the Beidou system go to sea, they can use the short message function to chat, and when they encounter danger, they can send a short message to the nearby coast guard for the first time. Positioning is not the end, and being able to send distress messages after positioning is the key. This is also the problem that Xu Ying focused on when building a national PNT (positioning, navigation, timing) system with Beidou as the core. She said that the future application of technologies that are optimistic about the Internet of Things and artificial intelligence is inseparable from the support of the basic information network, and the characteristic services provided by Beidou for the deep integration of navigation and communication are an indispensable part of it.
Beidou satellite navigation system Beidou
Beidou's other advantages, such as interstellar links and hybrid constellations, are many more, reducing dependence on ground facilities while also improving accuracy, reliability, and coverage. In addition, another core advantage of Beidou is its ultra-high-precision positioning technology, which was also selected as one of the "Top Ten Breakthrough Technologies in the World" in 2021 MIT Science and Technology Review. Authoritative release: MIT Science and Technology Review's 2021 "Top Ten Global Breakthrough Technologies" Among the methods currently widely used in the Beidou system, one is real-time dynamic (RTK) positioning, with an accuracy of up to 3cm or less; the other is precise point positioning (PPP), which can also achieve centimeter-level accuracy. Ultra-high-precision positioning for Beidou opened up a new application possibility, has been used in landslide prone areas of the surface of the monitoring, successful early warning of many landslide disasters, etc., so that residents can evacuate in advance; in addition, it can also serve the refined weather forecast, help environmental monitoring and environmental protection and other industries. What can Beidou do? The official reply is: Beidou application only has the limitation of imagination, there is no limitation of ability.
Xu Ying, National Science and Technology University Douyin
In addition to devoting herself to the scientific research and construction of the Beidou satellite navigation system, Xu Ying has played an indispensable role in the publicity and promotion of the Beidou system. Closely following the national call of "scientific and technological innovation and scientific popularization are the two wings of innovation and development", she participated in a number of popular science and technology TV programs, and conducted a series of popular science in the form of a talk show on the official Douyin number @ National University of Science and Technology of the University of Chinese Academy of Sciences, which has attracted more than 32 million people to watch and was praised by netizens as the "Beidou Goddess"; "People's Daily" even published an article saying: "Science popularization needs more Xu Ying." ”
She said
"The universe is full of heaven and earth, and the Big Dipper is a loyal guardian from 20,000 kilometers away."
At present, Xu Ying continues to work on the Beidou satellite navigation system, and the main research directions include pedestrian position estimation (PDR) and the response to problems such as "Urban Canyon" and "Multipath" in the city, and as always, expand the application mode and scenario of the Beidou system from the perspective of close to life, and improve the application efficiency. Perhaps it's time to change the phrase "Planet Earth is blue, andthere's so much we can do."
Big Dipper Pixabay
Chinese Sky Eye
We see farther than anyone
Navigation on Earth brings a lot of convenience to our lives, but what about in the vast universe without a given coordinate system? If we want to provide positional navigation and timing for deep space travel, we need something similar to the latitude and longitude of Earth as a reference, and pulsars are one of the most promising discoveries at present. Therefore, the discovery and observation of pulsars has become an extremely important part of the space industry. So, what are pulsars? How can we "see" them? A pulsar is essentially an ultra-high-density object with very fast spins, and its radiation comes from the polar crown region of its own strong magnetic field. Fortunately, when the pulsar radiation signal is turned in the direction of the Earth's line of sight at the polar crown, we can capture its pulse signal through radio telescopes.
Schematic diagram of pulsar radio radiation Yao Rui
She said
"A pulsar is like a very accurate clock, and if you can find a pulsar with a relatively stable signal, it will provide a good benchmark for deep space exploration."
If we need to look for stars in the universe at night, then the radio telescope undoubtedly gives us a pair of strengthened eyes, can achieve ultra-long-distance, all-weather astronomical observations, and the world's largest single-aperture radio telescope is not elsewhere, that is, our China FAST (Five-hundred-meter Aperture Spherical radio Telescope), is a 500-meter aperture spherical radio telescope. The person who gave this "Chinese heavenly eye" a "pupil" is one of the representative figures, Yao Rui, a young researcher of fast engineering at the National Astronomical Observatory of the Chinese Academy of Sciences and the current head of the mechanical team of the FAST Operation and Development Center.
Yao Rui's relationship with FAST is very wonderful, as early as the master's degree in fast feed support research, and in 2010 just graduated, Yao Rui officially joined Professor Nan Rendong's "China Sky Eye" research team, and in just two years was appointed as the head of fast feeder cabin, when she was only 28 years old. It should be known that the feed module is one of the most core components of the "Chinese Tianyan", the feeder refers to the telescope used to receive cosmic signals device system, and the feed chamber is used to place this system. Whenever she talks about this, Yao Rui admires Professor Nan Rendong, saying that she has not only gained the power of idols from Professor Nan, but also the power of trust, because it is Professor Nan who does not stick to age and seniority, and advocates that the young talent Yao Rui is alone.
Nan Rendong People's Daily
Although the original design was the Arecibo telescope in the United States (the world's largest radio telescope at that time, with an aperture of 305 meters), FAST greatly surpassed the former after its completion, becoming the world's largest single-aperture, highest sensitivity and strongest comprehensive performance radio telescope in one fell swoop. Such achievements benefit from the three major technical independent innovations of "China Tianyan":
FAST Radio Telescope FAST Project
- The topography of the karst giant depression in Qiannan Prefecture, Guizhou Province, where FAST is located, has natural spherical characteristics, which reduces a lot of construction projects as a site, and a good electromagnetic environment is a "good home" for radio telescopes;
- Independently developed active deformation reflector technology, changing the spherical surface (the design adopted by Arecibo) from the original design to a parabolic surface for signal aggregation, which greatly reduced the overall frame and feeder chamber quality, and improved the signal reception efficiency;
- Using optical mechatronics technology, independent research and development of light cable drag feeder platform and parallel robot to achieve high-precision pointing tracking of receivers;
Stewart platform (six-bar parallel robot)
FAST project
The third point is also the direction of Yao Rui's main attack. After comparing a variety of options, she and her team determined the feeder module design scheme of the 6-cable parallel robot, and creatively adopted the double linear wheel instead of the spiral wheel in the hoist, the rotating wheel instead of the fixed wheel, etc., which not only fixed the cable position of the flexible parallel robot, simplified the mathematical model, but also improved the accuracy of the feeder cabin control. The final result is a self-developed two-stage parallel robot as a feeder high-precision pointing structure: the world's largest cable-parallel robot (span of 600 meters) pulls a feeder cabin weighing up to 30 tons, at an altitude of more than 140 meters, within a range of 207 meters to achieve feed source positioning, combined with the large Stewart platform (six-bar parallel robot) in the feeder cabin, to achieve a feeder positioning accuracy of 10 mm. The final solution not only satisfies the high-speed, flexible movement of the feeder in 5 directions, but also minimizes the impact on the efficiency of telescope observation.
FAST Feeder System Yao Rui
As the "keeper" of "China's Sky Eye", Yao Rui has been deeply cultivating this field for more than ten years, making outstanding contributions to the astronomical observation and aerospace industry in the mainland, and as a "pioneer", she was deservedly selected into the 2018 MIT Science and Technology Review "35 People Under 35 Years old" China list.
Yao Rui Yao Rui
Since the discovery of the first pulsar in 1967, more than 2,700 pulsars have been discovered by mankind, and FAST has found more than 300 pulsars, even millisecond pulsars, in just four years from the completion and commissioning of fast from September 2016 to january 2020, more than 300 pulsars, including millisecond pulsars, have contributed important forces to the development of astronomical science and technology in China and even the world, laying a solid foundation for future interstellar navigation. In addition, FAST's powerful performance can help researchers detect dark matter, measure the mass of black holes, explore the origin of the universe, and even discover planets that may be suitable for human habitation in the future.
In Yao Rui's view, the role of the FAST radio telescope is to help human beings more sensitively distinguish meaningful sounds from the white noise of the universe.
FAST Summer Yao Rui
She said
"It can receive electromagnetic signals that are 1351 light-years away, and cicadas can be heard from thunder."
At 00:00 Beijing time on March 31, 2021, the "China Sky Eye" was officially opened to the world and accepted observation applications from scientists around the world. This is fast's solemn commitment to "science without borders", a "great power weapon".
Gravitational waves: a different starry sky
If the radio telescope above is one of the most sophisticated cosmic observation methods for human beings, then the following sounds almost in the category of science fiction.
In fact, the first time most people have heard of gravitational waves, they probably came from the well-known writer Liu Cixin's science fiction work "The Three-Body Problem". "The epee has no edge, the big coincidence does not work", "Wallfacer" Luo Ji retreated under the cynical appearance, as the "most ordinary of the Wallfacers", but finally realized the chain of suspicion and the famous "Dark Forest Law", and used the gravitational wave broadcast system to establish a dark forest deterrent system, became a "sword bearer", and single-handedly resisted the three-body invasion for 54 years.
"Three-Body: Dark Forest" Liu Cixin
So, what exactly is this gravitational wave that has fascinated countless scientists around the world? Why can it broadcast a coordinate information to the entire universe? This starts at the beginning. Einstein proposed general relativity in 1915 and published it in 1916, in which he predicted the existence of gravitational waves. In general relativity, gravity is considered an effect of the curvature of space-time, while gravitational waves are ripples in the curvature of space-time that propagate outward from a radiation source at the speed of light in the form of waves that transmit (dissipate) energy in the form of gravitational radiation. In other words, gravitational waves are a type of material wave produced by the violent movement and change of matter and energy.
The spatiotemporal unity of general relativity NetEase
In fact, even human movement produces gravitational waves, and according to the law of conservation of energy, gravitational waves must take away mass or energy. At this point, some people may have some bold ideas, such as whether gravitational waves are feasible for weight loss. However, the gravitational waves generated by people walking around are too weak for precision instruments to measure, let alone "lose weight"... In fact, even the gravitational waves generated by the Earth's orbit around the Sun have a radiation energy of only 200 W, which is almost negligible compared to the vast Earth, and cannot be observed by the most advanced detector LIGO.
Since the publication of general relativity, countless scientists have tried to confirm and even detect the existence of gravitational waves. So, what is the purpose of such a painstaking search for gravitational waves? In fact, all of our explorations and studies of the universe so far have been based on the analysis of electromagnetic radiation, such as optical telescopes and radio telescopes. However, many substances in the universe have gone beyond the scope of electromagnetic radiation, and only through the analysis of electromagnetic radiation to understand the universe, we can only see the appearance of the universe, and can never touch the essence of the universe.
Gravitational waves have two very important and unique properties, one is that no matter is required to exist around the gravitational wave source, then there will be no electromagnetic radiation; the other is that gravitational waves can pass through the traveling objects almost unhindered. This property determines that it can carry more information about astronomical phenomena that cannot be observed by traditional methods such as electromagnetic radiation, which can bring us a new understanding of the operation of the universe; at the same time, gravitational waves can also provide a way to observe the extremely early universe, which is also impossible in traditional astronomy.
Schematic diagram of gravitational waves at Xinhua Net
In the 1970s, Rainer Weiss was inspired by the experimental science of gravitational waves to propose a gravitational wave laser interferometer detection scheme based on the principle of The Michelson interferometer, which is the prototype of the world's most advanced gravitational wave observatory high-tech LIGO (aLIGO) today; in 1983, the National Science Foundation (NSF) was founded by Reiner Weiss, Kip Thorne and Ronald Drever) a steering group of three scientists to conduct a feasibility study for LIGO. In 1994, LIGO finally received a $395 million long-term grant from the NSF to begin construction of LIGO stations; by 2002, LIGO began searching for gravitational waves. It wasn't until LIGO was significantly upgraded more than a decade later that gravitational waves were detected directly on September 14, 2015, and released in 2016. The discovery proved to be gravitational waves from a binary black hole collision and merger event 1.3 billion years ago, and its direct detection became the final and most important "missing puzzle" to verify general relativity.
Binary black hole collisions and gravitational wave detection LIGO
From Einstein's prediction to the actual detection of gravitational waves, exactly 100 years have passed in between, without the sweat and efforts of countless scientists, and for Yu Haocun, who just joined the LIGO project with the MIT Boyi in 2015, this is an extremely fortunate start. After that, she also experienced another blockbuster event in LIGO and even human history, that is, at 8:41 EST on August 17, 2017, a gravitational wave signal named GW170817 was detected by the LIGO cooperative, marking the first time that humans directly detected a magnificent ripple in space-time (gravitational waves and their accompanying electromagnetic signals) from the merger of two neutron stars, and humans finally not only "heard" but also "saw" the signal of gravitational waves. During this period, Yu Haocun also grew rapidly and soon became the leader in LIGO. She led the installation and commissioning of the compressed vacuum state in aLIGO between 2017 and 2019, achieving the first use of the compressed vacuum state in the high-tech LIGO detector, which greatly improved the sensitivity of the detector – up to 1.4 times (or 3 dB) above 50 Hz and enabled aLIGO to increase the expected detection rate by 50% in its third observation run, increasing the event capture frequency from monthly to weekly detection of gravitational waves.
Two neutron stars combined with the imagination of NSF & LIGO
In 2020, by injecting a high-intensity compressed vacuum state into the aLIGO detector, Yu Haocun directly observed the quantum radiation pressure noise effect (QRPN) generated by a 200 kW laser on a 40 kg mirror for the first time. This proves that quantum reactions and Heisenberg's uncertainty principle still hold true on the macroscopic human scale. LiGO's design sensitivity is dominated by quantum noise, and Yu Haocun uses the quantum correlation generated by the coupling of the strong light system in aLIGO to achieve the quantum noise that breaks through the "standard quantum limit" (SQL) in the measurement of the displacement of the kilogram mirror at room temperature, which is the first practical application of the "quantum nondemolition technique" in the gravitational wave detector. The sensitivity of the detector is greatly improved.
Schematic diagram of LIGO detection principle LIGO
With all of the above, Yu Haocun, who is now a postdoctoral researcher in physics at MIT, was selected as a "visionary" in the 2021 MIT Science and Technology Review '35 Under the Age of 35' China list.
Yu Hao Cun Yu Hao Cun
While conducting such cutting-edge basic scientific research, Yu Haocun is often asked, what is the use of gravitational waves? Her answer to this is that basic scientific research itself has a lag, and the practical application of gravitational waves is now very limited, and it is of great significance only in the field of astronomy. But just like electromagnetic waves more than a hundred years ago, someone asked Maxwell what is the use of electromagnetic waves? Maxwell said, "I really can't tell you what it does right now, but we can wait and see." That is to say, she believes that gravitational waves will eventually become one of the forces that will change the world.
She said
"Humanity has always been looking for a unified theory of the world, and so have I."
Special relativity equates mass and energy into the same equation, while general relativity further pulls time and space into the same system, and human cognition of the world is constantly improving and deepening. When talking about his personal research direction and ultimate goal, Yu Hao, who first brought quantum mechanical phenomena to the macroscopic human scale, said that the large-scale macroscopic world and the small-scale quantum field of the gravitational field are each divided into one faction, and their respective theoretical research is completely separate. She hopes to combine these two fields into the same system, so she calls her research direction "Quantum Gravity", hoping to do more research on the overlapping parts of the quantum field and the gravitational field, and bring more quantum field phenomena to the macroscopic scale, and vice versa.
Einstein in "Ripples of Time" knows
"The most incomprehensible thing about the universe,
It lies in the fact that it can be understood. ”
—Albert Einstein
Looking up is a gesture
Nothing to do with the starry sky
Humans emerged from the cave, climbed over the hill, and saw fire for the first time. We cross the ocean, reclaim the wild continent, and dream of soaring into the sky. The history of mankind is an adventure-filled Odyssey. Why do we look up at the stars? Just because it's the next stop.
The famous British dish dark cuisine "Looking up at the stars" image source network
Salted fish are so spelled,
What reason do you have not to look up?
The development of the world needs science, and women are the indispensable backbone of its development.
Since 1999, MIT Technology Review Has selected "35 Under 35" (TR35) from around the world every year, which is one of the most authoritative evaluation systems for young talents in the field of science and technology. In 2017, the TR35 China Selection was officially launched, and has been held for five years, among which many outstanding young female scientists have been successfully selected every year.
【Registration in progress】
2022 "Under 35 Years Old Scientific and Technological Innovation 35 People" China's registration is in full swing! Young scholars, researchers, inventors, and technology entrepreneurs under the age of 35 in China (including Chinese currently overseas) are welcome to apply for the election, and also solicit nominations from all walks of life to jointly find the 35 people who are most likely to change the world.
【Inquiry E-mail】
Resources:
1.https://ieeexplore.ieee.org/document/9386073
2.https://ieeexplore.ieee.org/document/9340362/references#references
3.http://science.china.com.cn/2022-04/11/content_41931511.htm
4.https://www.ligo.caltech.edu/page/about-aligo
5.https://baike.baidu.com/item/%E9%BA%A6%E5%85%8B%E6%96%AF%E9%9F%A6%E5%A6%96/618888?fr=aladdin
6.http://webhome.auburn.edu/~smith01/notes/maxdem.htm
8.https://www.sohu.com/a/227998584_614840
9.https://www.zhihu.com/question/23724276
12.https://baijiahao.baidu.com/s?id=1712227258135656387&wfr=spider&for=pc
13.https://baijiahao.baidu.com/s?id=1629514353775267838&wfr=spider&for=pc
14.https://xuewen.cnki.net/CJFD-GWDT200502009.html
16.https://zhuanlan.zhihu.com/p/30216737
18.https://pansci.asia/archives/43586
22.https://people.ucas.ac.cn/~0023545
24.https://www.bilibili.com/video/BV17t411n7dF
27.https://www.sohu.com/a/63002277_224832
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