Confused About Traveling at the Speed of Light?

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Discussion Overview

The discussion revolves around the concept of traveling at relativistic speeds, specifically addressing the implications of speed relative to the speed of light. Participants explore the nuances of how speed is measured in different reference frames and the confusion surrounding the perception of light's speed in relation to moving observers.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses confusion about how speeds like .5c or .9999c can be discussed, questioning if this implies that one's speed is always zero compared to light.
  • Another participant asserts that speed is measured relative to stationary objects, not directly against the speed of light.
  • A different participant claims that one's speed is equivalent to 300,000 km/s when compared to light, but later acknowledges misunderstanding and agrees with another participant's clarification.
  • A repeated point emphasizes that when discussing speeds like 0.5c or 0.9999c, it is in relation to a specific frame of reference, such as Earth, while light remains at speed c in all frames.

Areas of Agreement / Disagreement

Participants exhibit some agreement on the idea that speed is relative to reference frames, but there is disagreement regarding the implications of this for understanding speeds in relation to light. The discussion remains unresolved with differing interpretations of how speed is perceived.

Contextual Notes

There are limitations in the discussion regarding the assumptions about reference frames and the definitions of speed in the context of relativity. Some mathematical steps and implications are not fully explored.

binbots
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I have always been confused about this. On here people constantly talk about traveling in a spaceship that goes .5c, or.9999c etc. But how can this be, no matter how fast one travels light will always travel at c compared to your reference frame. Does this not mean that no matter how fast you travel your speed will always equal 0 compared to light?
 
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You are correct. So the speed of a spaceship (or anything else, for that matter) is never measured with respect to the speed of light, it is always measured relative to stationary objects.
 
I don't think so. Your speed equals 300000 km/s compared to light.

Edit: Sorry binbots, I didn't understood your question. Russ is right.
 
Last edited:
binbots said:
I have always been confused about this. On here people constantly talk about traveling in a spaceship that goes .5c, or.9999c etc. But how can this be, no matter how fast one travels light will always travel at c compared to your reference frame. Does this not mean that no matter how fast you travel your speed will always equal 0 compared to light?
When people talk about a spaceship traveling at 0.5c or 0.9999c, they mean with respect to some other frame (say the earth). In that frame you are traveling at 0.5c or 0.9999c and light, of course, is traveling at c.

In your frame you are at rest and light travels at speed c with respect to you.
 

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