.. _fundamentals:

Fundamentals
============

This section provides the conceptual background needed to understand what
Homodyne does and why it works.

.. toctree::
   :maxdepth: 2

   what_is_xpcs
   analysis_modes
   homodyne_overview
   parameter_guide

----

**What you will learn:**

- What X-ray Photon Correlation Spectroscopy (XPCS) measures and how the
  two-time correlation function C2 encodes dynamics.
- The core homodyne equation relating C2 to the intermediate scattering
  function C1.
- The difference between ``static`` and ``laminar_flow`` analysis modes and
  when to use each.
- How Homodyne's physics model translates experimental parameters into a
  predicted C2 matrix.

**Prerequisites:** No prior XPCS or JAX experience required for this section.
