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STEM Concepts

Follow an equation, work through an example, or check an assumption. Browse 69 concepts across mathematics, physics and computing.

All📐Mathematics(19)⚛️Physics(12)🔄Algorithms(7)🏗️Data Structures(8)🤖Machine Learning(10)🧠CS Theory(5)🖥️Systems(2)🌐Networking(3)⚙️Engineering(2)🧪Chemistry(1)
S=k_B\ln\Omega
Physics

Boltzmann Entropy

Connects microscopic states to thermodynamic entropy

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Wt−Ws∼N(0,t−s),0≤s<tW_t-W_s\sim N(0,t-s),\qquad 0\le s<tWt​−Ws​∼N(0,t−s),0≤s<t
Physics

Brownian motion

A continuous random path with independent Gaussian increments.

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\lambda = \frac{h}{p}
Physics

de Broglie Wavelength

Matter has wave-like properties at quantum scales

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u(t)=e^{-t/\tau}
Physics

Exponential Decay

How quantities decrease over time (radioactivity, capacitors)

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\nabla \cdot \mathbf{E} = \frac{\rho}{\varepsilon_0}
Physics

Gauss's Law (Electric)

How electric charges create electric fields

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∂u∂t=α∇2u\frac{\partial u}{\partial t}=\alpha\nabla^2u∂t∂u​=α∇2u
Physics

Heat equation

How differences in temperature spread and smooth out.

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\Delta x \Delta p \geq \frac{\hbar}{2}
Physics

Heisenberg Uncertainty Principle

You cannot precisely know both position and momentum

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E=mc^2
Physics

Mass-Energy Equivalence

Einstein's equation showing mass and energy are interchangeable

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F=G\frac{m_1m_2}{r^2}
Physics

Newton's Law of Gravitation

How masses attract each other across space

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F=ma
Physics

Newton's Second Law

Force equals mass times acceleration — the foundation of mechanics

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⚛️

theory

Physics

Noether's theorem

Continuous symmetries link physical laws to conserved quantities.

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i\hbar\frac{\partial}{\partial t}\Psi(\mathbf{r},t)=\hat{H}\Psi(\mathbf{r},t)
Physics

Schrödinger Equation

Describes how quantum states evolve over time

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