Unraveling the Mysteries of Speed: From Particles to Galaxies

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Discussion Overview

The discussion revolves around the concept of speed and how it is measured in different contexts, particularly in relation to particles and celestial bodies. Participants explore the implications of combining velocities according to the rules of relativity and the challenges of understanding motion in a relativistic framework.

Discussion Character

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

Main Points Raised

  • One participant questions how to reconcile the high speeds of particles with the velocities of Earth, the solar system, and the galaxy, suggesting a potential misunderstanding of speed limits set by relativity.
  • Another participant emphasizes the need to combine velocities according to relativity to avoid nonsensical results.
  • There is a discussion about whether the relative speeds of particles from CERN are affected by the motion of Earth and the solar system, with some suggesting that these factors are irrelevant in certain contexts.
  • A participant reflects on the organic nature of science and the complexity of measuring speeds when accounting for multiple reference frames.
  • It is noted that there is no absolute speed, and the importance of stating speeds relative to a specific reference frame is highlighted.
  • One participant suggests that the total velocity measured by an observer will not simply be the sum of individual velocities due to the principles of relativity.

Areas of Agreement / Disagreement

Participants express varying levels of understanding regarding the implications of relative motion, with some agreeing on the necessity of relativity in measuring speeds while others remain uncertain about the complexities involved. The discussion does not reach a consensus on all points raised.

Contextual Notes

Participants acknowledge the challenges of measuring velocities in different reference frames and the potential fluctuations in measurements based on relative motion. There are unresolved questions about how to fully account for all variables in speed measurements.

Who May Find This Useful

This discussion may be of interest to those exploring concepts in relativity, physics students grappling with the implications of speed and motion, and individuals curious about the complexities of measuring velocities in different contexts.

YbNvS
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Ive been thinking about the movement of things recently. How we measure things here on Earth but for some reason we don't add up all the variables... its kinda weird. So here is a general question that has been giving me a big ache. So, for instance, If particles can be accelerated to 0.99999999 the speed of light, and the Earth traveling around the sun at 108,000 km/h and the solar system moves at around 675,000 km/h and our galaxy moves throughout space at around 900,000 km/h, than what is really going on here... maybe I am missing something but would that mean we have already blown past the speed of light? I'm sure I can be proven wrong very easily haha.

This is not homework or anything like that, just something that has been on my mind and i would love to hear what professionals and academics have to say about my silly observation!
 
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You need to combine those velocities according the rules of relativity. You otherwise get nonsensical results.
 
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Ok, so things kinda only work in little bubbles? Thats really fascinating, its like science is organic. So when the cern guys do their relative speed test or whatever, they probably account for all of those variables or bassically they don't need to?
 
For instance, if a particle from CERN got released and continued traveling at its speed in a straight line the base speed of it from Earth the solar system and the galaxy dosent matter at all? It just stays relative regardless? Anyway, measuring those variables would be hard and they probably fluctuate depending on if Earth is moving with or against the solar system in its rotation. Would science work differently if we could account for everything :P? No one has to answer me, these questions are very silly and I am not trying to trivialize the wonders of science here, its just amazing for me thinking about it all and not knowing how to think about it quite yet...
 
YbNvS said:
... its just amazing for me thinking about it all and not knowing how to think about it quite yet...

A good place to begin is, whenever you say, "moving at NN speed", always add, "relative to X". This is easy and important to get into the habit of because there is no such thing as absolute speed. Swallowing that pill isn't easy.

In the case of multiple velocities as you've mentioned, the total velocity as measured by an observer will not be the sum of the pieces measured by other observers. There is an additive velocity formula that always keeps relative velocities less than 'c' (except for light, which is always measured locally at 'c').
 
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YbNvS said:
Ok, so things kinda only work in little bubbles? Thats really fascinating, its like science is organic. So when the cern guys do their relative speed test or whatever, they probably account for all of those variables or bassically they don't need to?

They don't need to. They are irrelevant. All that matters to them is the speed of the particles relative to their starting point which is the same reference frame as their ending point --- the accelerator. Any motion that the accelerator has is irrelevant.
 
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I need some time to take this all in, this really has me thinking about some strange and interesting things. I am going to sleep on this. Thank you guys!
 
YbNvS said:
I need some time to take this all in, this really has me thinking about some strange and interesting things. I am going to sleep on this. Thank you guys!

Definitely strange while learning relativistic concepts, and always interesting. You'll find a lot of "thought experiments" posted in the GR section. They're a good way to drill down to the nuts and bolts of any details you're trying to reconcile. It's best to keep thought experiments as simple as possible to focus on the area in question. Here's a link to a recent, somewhat light-hearted thread that's kinda' related to your post today - this might get you of to a good start.

> > SR Question
 

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