earthquake energy

…plate tectonics

body waves

Travel through the earth (travel through rock).

p waves

compressional waves, “primary”. first to arrive. can travel through anything.

s waves

move the ground up and down/side to side.

surface waves

Travel through only through the surface, when body waves hit the surface this happens.

L Waves

left and right; circular path left and right. moves faster

R waves

up and down; particles underground follows a circular path up and down. “ocean waves” back and fourth.

OG Theory by Wegener

evidence for continual drift

• fossil distribution
• geologic units (edges of stuff fit together)

criticism

• OG theory couldn’t explain why stuff moved

Seafloor Spreading

• mid-ocean ridges: submarine mountain ranges
• deep-sea trenches: trenches in the depth
• fracture zones: vertical cracks

Paleomagnitism

Because earth magnetic field changes, measuring sediment polarization helps us figure out where stuff moved.

The magnetic poles, unlike other planets, don’t go anywhere. But every so often they reverse.

Background

1. originally, multi-agent team pre-assigns roles
2. LLMs are heterogeneous, but they are treated homogeneously
3. problem decomposition is hard

Eval

synergy

• weak synergy: team >= average member
• strong synergy: team >= best member

Human teams reliably achieve strong synergy IFF when expert identity is given (e.g., the teams easily know who is the expert).

Dataset

NASA moon survival / lost at seay

Rank 15 items by importance

Student body president

Different people are given different information + shared info. Hidden-profile (shared info + unique info must be paired to reveal the right one.)

convex-concave problems

Heuristic method for solving a specific type of non-convex problem. Solves a small sequence of convex problems.

difference-of-convex function

For:

\begin{equation} h\qty(x) = f\qty(x) - g\qty(x) \end{equation}

for convex \(f\qty(x)\) and \(g\qty(x)\).

some examples

• a convex quadratic, except the \(P\) in \(\qty(\frac{1}{2}) x^{T}Px\) is not PSD; we express this in terms of \(P = P_{\text{psd}} - P_{\text{nsd}}\). And thus we can get: \(\qty(\frac{1}{2})x^{T}P_{\text{psd}} x - \qty(\frac{1}{2})x^{T}P_{\text{nsd}}x\)

majorization

Taylor approximation: