Basic question about speed of light situation

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Discussion Overview

The discussion centers around the behavior of light, particularly the speed of photons and how they interact with each other and with objects moving at relativistic speeds. Participants explore concepts related to the speed of light, the implications of light traveling at speed c, and the effects of relative motion on the perception of light.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether a photon created after another photon traveling in the same direction would ever catch up, suggesting that this may only apply to objects moving slower than the speed of light.
  • Another participant agrees with the initial assertion regarding the behavior of photons.
  • A later post introduces a scenario involving two starships traveling at relativistic speeds, proposing that the speed of one starship relative to another can appear greater than expected, which may challenge intuitive understandings of speed.
  • Another participant presents a variation of the original question, stating that even if a photon is emitted from a fast-moving starship, it will not catch up to an earlier photon, as both travel at the speed of light.
  • This participant also discusses the effects of relative motion on the perception of light's wavelength, drawing an analogy to the experience of a boat moving through waves.

Areas of Agreement / Disagreement

There is some agreement on the behavior of photons and their speeds, but the discussion includes multiple competing views regarding the implications of relativistic speeds and how they affect the perception of light and motion.

Contextual Notes

Participants express uncertainty regarding the implications of their claims, particularly in relation to relativistic effects and the nature of light. The discussion does not resolve these uncertainties or assumptions.

Who May Find This Useful

This discussion may be of interest to those exploring concepts in relativity, the nature of light, and the implications of high-speed motion in physics.

fluidistic
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Hi,
I've read for any object, no matter how fast its motion is, it will always be "hit" by light at the speed of light. Does this also apply for light?
In other words : Say there's a photon going in a way and another photon is created to go in the same way, but about 5 seconds later. I guess the last photon won't reach the other one that is already 5 seconds ahead. It would only apply for objects going less fast than the speed of light, right?
 
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Right.
 
Thanks for clearing my doubt.
EDIT: By the way I'm sorry I posted this question in a wrong section. I didn't know exactly where it'd fit better and I made a bad choice.
 
fluidistic said:
Thanks for clearing my doubt.
EDIT: By the way I'm sorry I posted this question in a wrong section. I didn't know exactly where it'd fit better and I made a bad choice.
You could be interested in this simple question: you are in a starship (let's call it ST1) traveling at 0.99c with respect to Earth (for example); another starship (ST2), faster than your, passes by you at 0.99995c. At which speed will you see ST2 traveling with respect to you?
It could, maybe, amaze you that the answer is: greater than 0.99c.
 
Another variation on the original question:

Even if the second photon is released from a starship moving at, say 0.9c, the second photon will still never catch the first...both move at c.

And if your speed varies as you mopve toward some distant light signal, you will still measure it's speed as c but as your speed changes your will detect the light as different colors...that is, different wavelengths (or equivatenly, different frequencies)...This is like running into head seas in boat...as you go faster the apparent wavelength shortens (in time) and you start to hit peaks and troughs faster...
 

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