Physics Path I · Developed alongside Between the Beats
The Signal and the Journey
Astronomy begins with a received signal. Follow it from source through the physical propagation channel to the receiver before using it to reconstruct cosmic history.
Topics
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What Do We Actually Observe?
What arrives is measured; distant source history is reconstructed.
CHANNELThe Universe as a Propagation Channel
Before decoding the source, ask what the physical journey may have done to the signal.
REDSHIFTRedshift and the Propagation Channel
Can a cumulative physical process rescale the frequency of the signal while preserving the structure that astronomy still receives?
SIGNALSupernova Duration and the Shape of the Signal
A complete frequency rescaling must carry the corresponding transformation of the information-bearing message in time.
BACKGROUNDThe CMB: Relic Signal or Propagation Response?
Could a long physical channel develop a near-universal background while preserving the angular and polarisation information observed on top of it?
HORIZONThe Soft Horizon: The Edge of Knowing
Near a reconstruction boundary, the surviving observed population may become increasingly biased toward exceptional signals such as quasars.