Is It Possible for Anything to Truly Move at the Speed of Light?

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Discussion Overview

The discussion revolves around the concept of whether anything can truly move at the speed of light (c), exploring mathematical implications and physical limitations. Participants examine the relationship between approaching the speed of light and the infinite energy required to reach it, as well as the mathematical representation of numbers like 0.9999... and their equivalence to 1.

Discussion Character

  • Debate/contested
  • Mathematical reasoning
  • Conceptual clarification

Main Points Raised

  • Some participants propose that if 0.9999... equals 1, then moving at 99.999...% of the speed of light could be considered the same as moving at c, raising questions about the validity of this mathematical perspective.
  • Others argue that the issue is fundamentally physical, asserting that infinite acceleration is required to reach the speed of light, which is not feasible.
  • One participant questions where the limit of speed is imposed when approaching c, suggesting a hypothetical scenario involving "infinity -1" and the implications of energy requirements.
  • Another participant clarifies that one never truly stops accelerating, but rather approaches c more slowly as energy consumption increases.
  • It is noted that "infinity minus one" is not a valid number, emphasizing the distinction between mathematical concepts and physical realities.

Areas of Agreement / Disagreement

Participants express differing views on the implications of mathematical representations versus physical limitations. There is no consensus on the feasibility of reaching the speed of light or the interpretation of mathematical proofs in this context.

Contextual Notes

Limitations include unresolved assumptions about energy requirements and the nature of infinity in relation to speed. The discussion does not resolve the mathematical versus physical perspectives on the topic.

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I know it is impossible(for now:wink:), but if we use the mathematical proofs that any non-zero number with a finite decimal notation has a counterpart with trailing 9's. So, unless that is not always true, then wouldn't anything moving at 99.999...% (supposing we reach that somehow)the speed of light be actually moving at c? Remember the proofs, 0.9999...=1

Correct me please, something is definitely not right.

regards,
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The problem is physical not mathematical. In order to get to the speed of light you need infinite acceleration.
 
Fragment said:
I know it is impossible(for now:wink:), but if we use the mathematical proofs that any non-zero number with a finite decimal notation has a counterpart with trailing 9's. So, unless that is not always true, then wouldn't anything moving at 99.999...% (supposing we reach that somehow)the speed of light be actually moving at c? Remember the proofs, 0.9999...=1

Correct me please, something is definitely not right.

regards,
Fragment
Yes, 0.9999...= 1. Therefore you cannot travel at either c or 99.999...% c. They are just different ways of saying the same thing.

Your question is precisely the same as "I know it is impossible to go at c, but suppose we used the letter a and let a= c. Wouldn't anything going at a be actually moving at c?"
Yes, and that is why you cannot travel at c or a?
 
Thank you for your explanation HallsOfIvy, learning is the greatest experience:biggrin:

Fragment
 
On second thought, where do we impose the limit of speed when getting close to c? It is common knowledge that 99.999... extends to infinity, but what is infinity -1? Where do we put the limit? In other words what is the fastest one could go? Going at 99.999...%c implies infinite energy required, so where must we stop, supposing we had an energy source equal to infinity -1?:rolleyes: Hopefully I was clear.

Fragment
 
You never stop accelerating. You just keep on getting closer and closer to c, approaching it more and more slowly.
 
A few points. One is that 0.9999... and 1.0000... are two different ways of writing the exact same number. (Like Halls of Ivy said). In this way they are no different than 1/2 and 0.5 are.

The other is that (infinity minus one) is not a number.
 
Of course not, it was just an example to try to explain what I meant, sorry about the sloppiness. I guess that's a good way to think about it, you keep accelerating more and more slowly, never reach c, but use up more, and more energy. Thanks for all the clarifications!
 

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