If light speed (not in a vacuum) was about human walking speed ....

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Discussion Overview

The discussion revolves around the concept of light speed being comparable to human walking speed, particularly in the context of science fiction literature. Participants explore various works of fiction that address altered light speeds and the implications of such changes on physics and storytelling.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Historical

Main Points Raised

  • Some participants reference specific science fiction works, such as Bob Shaw's "slow glass" and George Gamow's "Mr Tompkins in Wonderland," which play with the idea of altered light speeds.
  • Others mention Greg Egan's writings, where light has mass, leading to different physical consequences in his fictional universe.
  • One participant describes "Redshift Rendezvous" by John E. Stith, highlighting its unique take on time and gravity in a spherical ship with a singularity.
  • There is a discussion about the implications of slowing light speed, with one participant suggesting that if light had mass, it could enhance momentum, allowing for novel propulsion methods in science fiction.
  • Some participants express confusion about the exotic nature of the original question, referencing real-world experiments where light has been slowed down in specific media.
  • There is a clarification attempt regarding the distinction between slowing light in a medium versus altering the fundamental speed of spacetime.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the implications of changing light speed or the nature of the original question. Multiple competing views and interpretations remain present throughout the discussion.

Contextual Notes

Some participants note the complexity of changing light speed and its interconnectedness with other physical laws, suggesting that such changes would have far-reaching consequences that are not fully explored in the literature referenced.

rootone
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If light speed (not in a vacuum) was about human walking speed ...
Did any sci fi writer try that?
 
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I met this idea once in a kind of 'relativity for young adults' book.
 
Can’t think of any. Changing the speed of light would change so many other things that it is linked to. Greg Egan is a very good SF writer who goes heavily into the science of his books (and I mean heavy), he wrote a trilogy set in a universe where light has mass and explored the consequences of that:

https://www.goodreads.com/book/show/9756310-the-clockwork-rocket
 
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Redshift Rendezvous by John E. Stith.

There's a singularity at the centre of the spherical ship, so time, light and gravity run differently on each onion-layered deck. On one inner deck, space-time curves such you can see around the circumference. If you stand and wait a little while, you can see your own back...

The author's extensive notes do apologise for taking liberties with Relativity. These necessitate a 'life-belt' to maintain the wearer's physiology despite the deranged physics.

IMHO, Mild Suspension of Disbelief aside, it is a well-wrought tale, full of twists, turns, villains and derring-do.
 
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rootone said:
If light speed (not in a vacuum) was about human walking speed ...
Did any sci fi writer try that?
You might find this (sadly) abandoned game demo interesting . . .
 
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Thanks for the interesting replies.
 
Ryan_m_b said:
Can’t think of any. Changing the speed of light would change so many other things that it is linked to. Greg Egan is a very good SF writer who goes heavily into the science of his books (and I mean heavy), he wrote a trilogy set in a universe where light has mass and explored the consequences of that:

https://www.goodreads.com/book/show/9756310-the-clockwork-rocket
If light was very slow I think it would effectively have mass and thus greatly enhanced momentum. Then rockets could work just by shining lasers or microwaves out the back for propulsion. At least for SF.
 
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rootone said:
If light speed (not in a vacuum) was about human walking speed ...
Did any sci fi writer try that?
In the first chapter of "Mr Tompkins in Wonderland" George Gamow treats c as a a bit above bicycle speed.
 
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  • #10
Fewmet said:
In the first chapter of "Mr Tompkins in Wonderland" George Gamow treats c as a a bit above bicycle speed.
This is one of my favorite books from long ago. I highly recommend it if only for the entertainment of seeing how he presents a variety of concepts in an exagerated form.
 
  • #11
Nik_2213 said:
Redshift Rendezvous by John E. Stith.

There's a singularity at the centre of the spherical ship, so time, light and gravity run differently on each onion-layered deck.

Didnt Dr Who have something similar in a recent episode?

Aside: My father did some of the lighting for Dr Who back in the 1960s and 70s.
 
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  • #12
CWatters said:
Didnt Dr Who have something similar in a recent episode?

Season 10, Episode 11.
 
  • #13
rootone said:
If light speed (not in a vacuum) was about human walking speed ...
Did any sci fi writer try that?

I don't quite understand what is so exotic about this. After all, Lene Hau slowed down light to 17 mph in 1999, and our world didn't turn "sci-fi" (she and her group went all the way and slowed it down to a complete halt a few years later).

Zz.
 
  • #14
ZapperZ said:
I don't quite understand what is so exotic about this. After all, Lene Hau slowed down light to 17 mph in 1999, and our world didn't turn "sci-fi" (she and her group went all the way and slowed it down to a complete halt a few years later).

Zz.
As I interpret the OP, the question is about slowing the characteristic speed of spacetime, not the actual speed of light pulses. I do not believe the former has yet been achieved ;)
 
  • #15
m4r35n357 said:
As I interpret the OP, the question is about slowing the characteristic speed of spacetime, not the actual speed of light pulses. I do not believe the former has yet been achieved ;)

The OP said (emphasis mine):

If light speed (not in a vacuum) was about human walking speed ...

Isn't this simply the speed of light in a medium? It has nothing to do with "characteristic speed of spacetime" if it is simply the speed of light being slowed down ".. not in a vacuum..".

Zz.
 
  • #16
ZapperZ said:
The OP said (emphasis mine):
Agreed, but as you say such a question is not really worth asking. Hence I attempted to read the OPs mind ;)
 
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