A mind experiment about speed and time

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Discussion Overview

The discussion revolves around a thought experiment involving a sphere moving at infinite speed relative to an observer, exploring concepts of motion, perception, and the implications of such a scenario on our understanding of physics. Participants engage with theoretical implications, the nature of speed, and the relationship between perception and reality.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant describes a scenario where a sphere moves infinitely fast, suggesting that it would appear still to an observer, raising questions about how fast the observer must walk to recognize its true motion.
  • Another participant proposes that negative mass could allow for superluminal speeds, although they express uncertainty about the existence of negative mass and relate it to the early universe.
  • A different viewpoint argues that if the sphere is infinitely fast, it would be impossible to perceive it as a sphere, as the observer cannot match its speed.
  • One participant draws a parallel to the concept of the Heisenberg Uncertainty Principle (HUP), suggesting that defining motion becomes problematic under certain conditions.
  • Another participant challenges the need for superluminal speeds, citing that a slower speed could still create the illusion of continuity, using the example of film frame rates.
  • A participant questions the physical laws in the hypothetical scenario, asking what alternatives exist for matter and forces in such an imaginary universe.
  • One participant speculates on the physical consequences of interacting with an infinitely fast object, suggesting it would generate disturbances and possibly lead to catastrophic outcomes.
  • Another participant posits that one would need to move infinitely fast around the sphere to notice its infinite velocity, implying that any slower speed would remain undetected.
  • A later reply corrects a previous claim about film frame rates, asserting that the standard is actually 24 frames per second and questions the logic behind the suggested speed of 16 m/s.

Areas of Agreement / Disagreement

Participants express a range of views, with no clear consensus on the implications of the thought experiment. Disagreements arise regarding the necessity of superluminal speeds, the nature of perception, and the physical laws that would govern such a scenario.

Contextual Notes

Participants highlight limitations in defining motion and perception under the conditions of the thought experiment, as well as the dependence on hypothetical scenarios that challenge established physical laws.

dr.eams
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According to Einstein's theory, the fastest speed in this world is the speed of light. let's break this role for a sec.

so here is the experiment:
imagine a sphere moves infinitely quick relative to us. as quick as if its omnipresent, it seems appearing at every position at each time.
now, this sphere is doing a rotation. its rotating around and its follows an orbit. when we touch it, no mater where we touch we can touch the sphere, which means to us, it is actually still! It becomes a donut-shaped still object to us, the observer.
now let us walk around this still object . the question is, how fast we walk relative to the donut to recognize it is actually a moving sphere?

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I can see what you're saying here. But, think of it this way. You can go at superluminal speeds if you have a negative net force of gravity acting on you, which'd mean that the space-time continuum is curved upward instead of downward. But this would almost certainly mean that the object should have a negative mass. Though, this could be argued. But how could an object have a negative mass? I have no clue, unless it does. It's like the beginning of the universe, it just happened. Well, at least that's how I understand it. We know for a fact that we don't know everything about the universe yet. M-Theory is like a puzzle. The edges are easy to find, but it's hard to work from the inside out. There's just a gap between the inside and the edges that makes it so we can't, as of yet, finish the puzzle. So, let's see what happens when we put negative masses, energy, and gravity into that gap...
 
If the sphere is traveling infinitely fast relative to us then we will never be able to see the sphere as a sphere because we will never be able to travel as fast as the sphere. Atleast this is my thought on it, good thought expirement though! :)
 
We already have something similar. We call it HUP, now you might point out that as we can choose a observable, neither of those properties are 'really' impossible to define, but in a measurement one of them will be. And although it doesn't speak about a 'speed' it still becomes impossible to define, which I like even better than the idea of 'motion' :)

It's quite foggy down there.
 
dr.eams said:
According to Einstein's theory, the fastest speed in this world is the speed of light. let's break this role for a sec.

so here is the experiment:
imagine a sphere moves infinitely quick relative to us. as quick as if its omnipresent, it seems appearing at every position at each time.
now, this sphere is doing a rotation. its rotating around and its follows an orbit. when we touch it, no mater where we touch we can touch the sphere, which means to us, it is actually still! It becomes a donut-shaped still object to us, the observer.
now let us walk around this still object . the question is, how fast we walk relative to the donut to recognize it is actually a moving sphere?

This has nothing to do with Einstein's theory. You don't need to go faster than light in order to give an impression of a continuum. For example, a standard rate for movies is 16 frames per second, which is very, very slow in comparison with the speed of light, and yet it's good enough to fool us into seeing a continuum instead of a series of 16 still frames. Based on this, I'd guess that you can make your sphere move at this speed (or about) and it should give you an impression that it is a donut.

So, to answer your question, how fast we have to walk to recognize that it is a sphere, take the speed of your sphere (it can be anything = S > F) and compare it to the speed necessary to fool us (that's the key = F), which, based on movie speed I'd guess at 16m/s, and get the difference: x = S - F = S - 16m/s
 
You'd have to change pretty much all the laws of physics to answer this question... we cannot be made of atoms with particles and have strong, weak, electromagnetic and gravitational force. So in this imaginary universe, what are your alternatives? Is matter basically continuous with no empty space? What are the forces in this imaginary universe?
 
It’s hard to imagine since it’s impossible. But OK. Wouldn’t it generate a huge electromagnetic field disturbance that would heat up everything around it to the point of exploding? Besides, I don’t think you’d be able to touch it. Instead, I think your finger would disappear. It would also generate an infinite amount of centrifugal force. So those are 3 clues that it’s not a donut. I don’t think you can ever tell it’s a sphere.
 
I would think that you would have to move infinitely fast around it before you could notice it's infinite velocity, to answer the question. Any other speed would just be infinitely slower than the sphere, leaving it unoticed.
 
Spacie said:
This has nothing to do with Einstein's theory. You don't need to go faster than light in order to give an impression of a continuum. For example, a standard rate for movies is 16 frames per second, which is very, very slow in comparison with the speed of light, and yet it's good enough to fool us into seeing a continuum instead of a series of 16 still frames. Based on this, I'd guess that you can make your sphere move at this speed (or about) and it should give you an impression that it is a donut.

So, to answer your question, how fast we have to walk to recognize that it is a sphere, take the speed of your sphere (it can be anything = S > F) and compare it to the speed necessary to fool us (that's the key = F), which, based on movie speed I'd guess at 16m/s, and get the difference: x = S - F = S - 16m/s

Just to set things straight, standard frame rate for movies is 24 fps, not 16. And how did you come up with 16 m/s? It is even more nonsensical than OP's question.
 

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