


On
1dimensional formal group laws in
characteristic zero 
On 1dimensional formal group laws in
characteristic zero
Jointly written with JENS
SCHWAIGER Aequationes
Mathematicae pages 16, 2014.
Abstract: Let 𝕂 be a field
of characteristic zero or, more general, a Qalgebra. A
formal power series F(x,y)=x+y+∑_{i,j≥ 1}
a_{i,j}x^{i}y^{j}∈ 𝕂[[x,y]] is called a 1dimensional formal group
law if F(F(x,y),z)=F(x,F(y,z)). Using some elementary methods, we
prove that for every 1dimensional formal group law F(x,y) there
exists a formal power series f(x)=x+∑_{n≥ 2}f_{n}x
^{n}∈ 𝕂[[x]] so that
F(x,y)=f^{1}(f(x)+f(y)).
harald.fripertinger "at" unigraz.at, February 15,
2018






On
1dimensional formal group laws in
characteristic zero 

