dorsal/arxiv
View SchemaA Newtonian pre-introduction to gravitational lenses
| Authors | T. Garel |
|---|---|
| Categories | |
| ArXiv ID | physics/0311038 |
| URL | https://arxiv.org/abs/physics/0311038 |
| DOI | 10.1088/0143-0807/25/6/009 |
| Journal | Eur. J. Phys. 25, 771 (2004) |
Abstract
Understanding the deflection of light by a massive deflector, as well as the associated gravitational lens phenomena, require the use of the theory of General Relativity. I consider here a classical approach, based on Newton's equation of motion for massive particles. These particles are emitted by a distant source and deflected by the gravitational field of a (opaque) star or of a (transparent) galaxy. The dependence of the deviation angle $D$ on the impact parameter $b$, and the geometry of the (source, deflector, earth) triplet, imply that different particle trajectories may reach an earth based observer. Since $D(b)$ does not depend on the mass of the particles, it is tempting to set the particles' velocity equal to the speed of light to get a (Newtonian) flavor of gravitational lenses phenomena. Orders of magnitude are obtained through a non technical approach and can be compared to the General Relativity results.
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"abstract": "Understanding the deflection of light by a massive deflector, as well as the\nassociated gravitational lens phenomena, require the use of the theory of\nGeneral Relativity. I consider here a classical approach, based on Newton\u0027s\nequation of motion for massive particles. These particles are emitted by a\ndistant source and deflected by the gravitational field of a (opaque) star or\nof a (transparent) galaxy. The dependence of the deviation angle $D$ on the\nimpact parameter $b$, and the geometry of the (source, deflector, earth)\ntriplet, imply that different particle trajectories may reach an earth based\nobserver. Since $D(b)$ does not depend on the mass of the particles, it is\ntempting to set the particles\u0027 velocity equal to the speed of light to get a\n(Newtonian) flavor of gravitational lenses phenomena. Orders of magnitude are\nobtained through a non technical approach and can be compared to the General\nRelativity results.",
"arxiv_id": "physics/0311038",
"authors": [
"T. Garel"
],
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"doi": "10.1088/0143-0807/25/6/009",
"journal_ref": "Eur. J. Phys. 25, 771 (2004)",
"title": "A Newtonian pre-introduction to gravitational lenses",
"url": "https://arxiv.org/abs/physics/0311038"
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