i thought this was made by friends of jean-pierre petit and his Janus model... I love the idea of negative mass ( because i love symetries in the laws of natur

i thought this was made by friends of jean-pierre petit and his Janus model... I love the idea of negative mass ( because i love symetries in the laws of nature) but i've got a hard time believing the geniuses of the early 20th century haven't already explored the idea.