Gravity is 10^32 times weaker than the other forces. Lisa Randall found a geometric reason why.
In 1999, with Raman Sundrum, she proposed the Randall-Sundrum model: we live on a 3-brane in warped five-dimensional anti-de Sitter space. Gravity leaks into the extra dimension and is exponentially diluted by the warp before it reaches us. The hierarchy problem becomes pure geometry.
First tenured woman theorist at Princeton and at Harvard. Author of Warped Passages. She wrote the libretto for an opera about the fifth dimension.
The weakness of gravity might simply be the shape of the unseen.
A 2×2 matrix A makes the plane flow by x′ = Ax, and each flow is one of nine kinds: points sink, escape, spiral, circle or settle on a line.
The kind is set by the eigenvalues of A, the roots of λ² − (tr A)λ + det A = 0. det A < 0 gives a saddle. Above det A = (tr A)²/4 they are complex: spirals, or a centre if tr A = 0. Below it, nodes; on it, star and degenerate node.
The stable spiral here has tr A = −1, det A ≈ 2.65, so λ = −0.5 ± 1.55i.
@lindabrasilse Pra quem anda de ônibus, é OBVIO que a linha 036 era necessária desde que o terminal do mercado foi reformado. Essas empresas de ***** parece q não entendem porra nenhuma de transporte público.
> Direita falando de matemática financeira
Expectativa: Teoria de Portfólios de Markowitz, Fronteira de Pareto, Otimização Bayesiana e Convexa, modelo Black-Litterman, Black-Scholes e Séries Temporais
Realidade: CIT, %, compra na alta e vende na baixa (kkkk)