Expanding universe and light detection

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SUMMARY

The discussion centers on the implications of the universe's expansion exceeding the speed of light, specifically referencing Hubble's law. According to the law, the velocity of a distant object is calculated as v=H_0 d, where v represents velocity, d denotes distance, and H is the Hubble constant. The Hubble limit, which corresponds to the speed of light, indicates an event horizon beyond which light from distant objects cannot reach us. Therefore, light emitted from objects receding faster than the speed of light will never arrive at our location.

PREREQUISITES
  • Understanding of Hubble's law and its components (Hubble constant, velocity, distance)
  • Familiarity with the concept of event horizons in cosmology
  • Knowledge of the speed of light as a fundamental constant
  • Basic grasp of the implications of cosmic expansion on light propagation
NEXT STEPS
  • Research the implications of Hubble's law on cosmological models
  • Explore the concept of event horizons in relation to black holes and cosmic expansion
  • Study the effects of relativistic speeds on light propagation
  • Investigate recent findings in cosmology regarding the expansion rate of the universe
USEFUL FOR

Astronomers, cosmologists, physics students, and anyone interested in the fundamental principles of cosmic expansion and light behavior in the universe.

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Sorry if this question has been reproduced elsewhere.

If the universe expands greater than the speed of light, c, will a light ray from a distant object never reach us? Lawrence Krauss gave a nice presentation and commented about this, but this has thrown my nose out of sorts because I think light will reach us regardless of frame speed, even a frame traveling greater than c oppositely.

Thanks for reading.

-EA
 
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The velocity of a distant object is given by Hubble's law
[tex]v=H_0 d[/tex]
where v is velocity, d distance, and H is a constant. The distance at which v=c marks the Hubble limit--more or less the event horizon--beyond which we cannot be causally connected. No, light will not reach us.
 

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