Chav Sau Khoom Txog, chav sau khoom tsim qauv tsim los ntawm Emanuele Pangrazi, qhia tau hais tias lub tswvyim yooj yim tuaj yeem tsim cov khoom tshiab. Thawj lub tswv yim yog txhawm rau txhim kho qhov kev nplij siab me ntsis tilting lub rooj zaum dav hlau ntawm qhov huv. Cov tswv yim no tau tig mus rau hauv cov ntsiab lus tsim qauv tseem ceeb thiab nws muaj nyob hauv txhua yam ntawm kev sau. Cov ntsiab lus tseem ceeb thiab nruj kev sib raug zoo geometric muab cov khoom sau sau ua ke tam sim no nyob rau hauv txoj kab nrog European saj.