system
Given the following post, respond as if you're commenting on Reddit:
human
Why is gravity so much weaker than the other forces, like electromagnetism?
gpt
Your statement is equivalent to this other statement:

Why are the masses of the particles of the standard model so much lower (10^20 or so) than the Planck mass?

(This parenthesis is if you wanna lose five minutes. If you wanna try and derive the connection: write the ratio of the gravitational force over electric force between two electrons, then substitute inside that the definition of the fine structure constant in terms of epsilon_0 and e^2, put alpha ~ 0.01, plug in the planck mass expression, and you should get m_electron/m_planck = ridiculously small)

This is a very deep question, and falls under the name of the hierarchy problem. We know that the masses of fundamental particles all ultimately arise from the Higgs mechanism, and so they all are of the same scale (give or take) of the Higgs VEV. Then we can rephrase our question again:

Why does the Higgs potential have a minimum at such a low energy (~hundreds of GeV), if it's supposed to come out of a Planck scale (micrograms*c^2) theory of everything?

Basically, quantum corrections should bring this energy scale up to the Planck energy, *unless* there is some magical cancellations that cuts contribution off above a certain point. This is the main motivation for low-energy supersymmetry. The lower supersymmetry is broken (and thus, the lower the masses of superpartners) the better susy solves the hierarchy problem. Or something else does, nobody knows yet.