Can someone tell me if these statements are right/wrong, and if wrong, why they are wrong?(adsbygoogle = window.adsbygoogle || []).push({});

Lets say you have a light (or more generally, EM) source a distance r from a black hole's core, with r > event horizon radius.

As you move closer towards the black hole, since the energy of a photon = hf, with h = constant, and the gravitational PE varies as 1/r...therefore the frequency fall due to red shifting falls as 1/r as well.

I get this equation relating the frequencies at 2 points and the radius from the black hole: (f1 - f2)/(f1 + f2) = GM(1/r1 - 1/r2)

If the above are true, then the event horizon for different frequencies of light varies. High frequency EM radiation will have a larger event horizon than low frequency EM radiation.

AFAIK, the event horizon is a fixed distance for light...

Am I looking at the problem too "classically"?

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Red shift frequency from a black hole

Loading...

Similar Threads for shift frequency black |
---|

B Why Light Experienced a Doppler Shift? |

I Redshift and atomic oscillations |

B Why do photons allow Doppler shift |

I Could emission theory produce Doppler-shift formula for moving mirrors? |

**Physics Forums | Science Articles, Homework Help, Discussion**