dorsal/arxiv
View SchemaThe "optical" version of the barn-pole problem
| Authors | Eric Baird |
|---|---|
| Categories | |
| ArXiv ID | physics/0106049 |
| URL | https://arxiv.org/abs/physics/0106049 |
Abstract
We present diagrams and simple calculations for the apparent (i.e. photographable) length of a moving ruler skimming the observer's position, under three different classes of model. Special relativity's predictions in this particular situation are the root-product average of the two more basic first-order predictions generated by simple "propagation timelag" arguments. We find that special relativity can legally predict either a photographable Lorentz contraction or a photographable Lorentz expansion in the "centred" ruler, depending on whether our camera is at the ruler's "apparent" or "official" centre.
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"date_created": "2026-03-02T18:00:35.310000Z",
"date_modified": "2026-03-02T18:00:35.310000Z",
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"abstract": "We present diagrams and simple calculations for the apparent (i.e.\nphotographable) length of a moving ruler skimming the observer\u0027s position,\nunder three different classes of model. Special relativity\u0027s predictions in\nthis particular situation are the root-product average of the two more basic\nfirst-order predictions generated by simple \"propagation timelag\" arguments. We\nfind that special relativity can legally predict either a photographable\nLorentz contraction or a photographable Lorentz expansion in the \"centred\"\nruler, depending on whether our camera is at the ruler\u0027s \"apparent\" or\n\"official\" centre.",
"arxiv_id": "physics/0106049",
"authors": [
"Eric Baird"
],
"categories": [
"physics.gen-ph"
],
"title": "The \"optical\" version of the barn-pole problem",
"url": "https://arxiv.org/abs/physics/0106049"
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