From Sam Edge, Ringwood, Hampshire, UK
Last time I checked, our theories of the universe would be down the tubes if anything could truly break Newton’s third law of motion, aka the conservation of momentum (28 October, p 14).
The idea that sperm can do so reminds me of . Upon detailed analysis, the flight mechanism is clear. And, in my view, so is the fluid dynamics involved in sperm propulsion. I don’t believe either involve violations of physical principles as we understand them.
