Uploaded November 2025 | Updated September 2026, 2 weeks ago
The 150-megaparsec “standard ruler” is said to link the early universe to the modern one.
But that ruler isn’t observed — it’s calculated using the same assumptions that define it.
This short unpacks the circular logic behind cosmology’s most trusted measuring stick.
The 150-megaparsec “standard ruler” is said to link the early universe to the modern one.
But that ruler isn’t observed — it’s calculated using the same assumptions that define it.
This short unpacks the circular logic behind cosmology’s most trusted measuring stick.










