Breaking the laws of physics is a big no-no 鈥� unless you happen to be a sperm. Earlier this year, a at Kyoto University in Japan found that microorganisms such as sperm and some algae propel themselves in a way that apparently breaks Isaac Newton鈥檚 third law of motion.
These micro-sized swimmers are equipped with long, slender filaments called flagella that jut out of their bodies like hair. These possess a property called 鈥渙dd elasticity鈥� that allows them to act without creating a reciprocal reaction, as Newton decreed all motion should.
When 快猫短视频 reported the work, it became our most popular story this year and was picked up by outlets around the world.
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鈥淭o be honest we were slightly surprised at the global impact of the article,鈥� say authors Kenta Ishimoto, Cl茅ment Moreau and Kento Yasuda.
But they think their research could help answer deep questions. 鈥淭his non-reciprocity is one of the most important features of living matter,鈥� say the researchers, and so it could be an important ingredient for answering the question of what makes life alive.
They are now working on quantifying the non-reciprocity of various living cells by calculating a number called the 鈥渙dd elastic modulus鈥� for different microscopic swimmers, both natural ones and artificial versions, such as tiny robots. The higher this number, the more the micro swimmer can wave its flagella and move, despite the fluid around it working to dissipate all its energy.
Through discussing with colleagues and reviewing the scientific literature, the researchers are looking to 鈥渇ind the odd elastic modulus wherever it is hiding鈥�, they say. One of their ultimate goals is to expand what they have learned so far to understand how whole collectives of odd-elastic microrobots could work together to complete tasks in contexts like biomedicine.
