Can the Speed of Light Be Exceeded by Manipulating Distance and Velocity?

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Discussion Overview

The discussion revolves around the concept of manipulating distance and velocity to exceed the speed of light, particularly through a thought experiment involving a strobe effect created by a fence with vertical slats. Participants explore the implications of this idea in relation to fundamental physics concepts, including Planck time and the limitations imposed by special relativity.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant describes an observation of sunlight flickering through a fence and proposes that increasing distance and velocity could result in a faster flicker rate, potentially below a Planck second.
  • Another participant questions the definition of "Planck second" and its significance, leading to a clarification that it is often confused with "Planck time."
  • A participant suggests that achieving a flicker rate below a Planck second would require either distances below the Planck length or velocities exceeding the speed of light, which would violate special relativity.
  • Further exploration includes a proposed method for achieving high-frequency pulses using a spinning disc with multiple openings and lasers, aiming for frequencies in the range of attoseconds.
  • One participant expresses skepticism about the thread's purpose, questioning whether it is merely rambling.
  • Another participant humorously notes the potential for interesting diffraction patterns resulting from the proposed setup.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of exceeding the speed of light through manipulation of distance and velocity, with some questioning the underlying assumptions and others exploring theoretical implications. No consensus is reached regarding the validity of the initial proposal or its implications.

Contextual Notes

Participants reference concepts such as Planck length and Planck time, but there is some confusion regarding their definitions and implications. The discussion includes speculative ideas that are not grounded in established physics, and assumptions about the feasibility of certain setups remain unresolved.

Edward Solomo
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Today I was driving down the road, on the side of the road, there was a fence made of many vertical slats.

I noticed that that sun was blinking on and off like a strobe light, as each individual slat would shield the sun, and each space in between the slats would expose it. I thought, if my car remained moving at the same speed, but my parallel distance between the fence was increased, the sun would flicker at an even faster speed.

In fact, if I were to increase my distance enough, and also increase my velocity, and decrease the distance between each slat, the time between each flicker would be less than a Planck second.

Am I missing something?
 
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What is a "Planck second"?
 
The time is takes light to travel one Planck Length.
 
Edward Solomo said:
The time is takes light to travel one Planck Length.

I think that's actually called the "Planck time".
 
Edward Solomo said:
Today I was driving down the road, on the side of the road, there was a fence made of many vertical slats.

I noticed that that sun was blinking on and off like a strobe light, as each individual slat would shield the sun, and each space in between the slats would expose it. I thought, if my car remained moving at the same speed, but my parallel distance between the fence was increased, the sun would flicker at an even faster speed.

In fact, if I were to increase my distance enough, and also increase my velocity, and decrease the distance between each slat, the time between each flicker would be less than a Planck second.

Am I missing something?

I would think the distance would either have to drop below the Planck length or your vehicle would have to travel faster than c (a ridiculous violation of SR) for that to occur, and most modern theories don't even posit lengths 'shorter' than the Planck length to have any meaning. Certainly not in the ever-popular string/M-theory, in which the intrinsic string length L[itex]_{s}[/itex], which is on the order of the Planck length, is considered to be the fundamental length.
 
Last edited:
What is a "Planck second", how does it differ from a regular second, and what makes you think it (or anything) is a minimum unit of time?
 
FalseVaccum89 said:
I would think the distance would either have to drop below the Planck length or your vehicle would have to travel faster than c (a ridiculous violation of SR) for that to occur, and most modern theories don't even posit lengths 'shorter' than the Planck length to have any meaning. Certainly not in the ever-popular string/M-theory, in which the intrinsic string length L[itex]_{s}[/itex], which is on the order of the Planck length, is considered to be the fundamental length.

Well, when I did the math, I realized it doesn't provide any practical way of getting a strobe frequency under the femtosecond.

It did get me to think about a way to time attoseconds though.

Imagine we had a thin cylindrical disc, centered about a laser. The sides of the disc is divided into 1 trillion parts, such that the laser can pass through each of the 1 trillion openings on the side of the disc.

We spin this disc 1,000 times per second, giving us 1 quadrillion hertz. Now, we take each individual pulse that exits the disc and we must find a way to divide it 1,000 times.

Perhaps you could let the laser pass through a very narrow fiber optic-like tunnel, with 1,000 appropriately spaced mini lasers that emit a laser perpendicular to the path of the laser, such that a capacitor would discharge for each of the 1,000 cells when the laser inference hit a critical value.
 
Is there a point to this thread other than a mindless rambling?

Zz.
 
it would give you some crazy diffraction patterns...like a disco ball.
 

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