A non-technical explanation for FTL quasar motions

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    Explanation Ftl Quasar
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Discussion Overview

The discussion revolves around non-technical explanations for the apparent faster-than-light (FTL) motions observed in quasars. Participants explore analogies and challenge the interpretations of redshift and its implications for quasar behavior.

Discussion Character

  • Exploratory
  • Debate/contested

Main Points Raised

  • One participant presents an analogy involving book deliveries to illustrate how FTL quasar motions may be misinterpreted, suggesting that the perception of speed does not imply actual faster-than-light travel.
  • Another participant questions the analogy, asking for a comparison of a postal strike to absorption by intergalactic dust, indicating a desire for deeper exploration of the analogy's implications.
  • A different participant challenges the original poster's stance on redshift, asserting that there is substantial data regarding quasars and redshift, and that promoting the idea of no evidence for intrinsic redshift requires defending against established literature.
  • This same participant cites a paper to support their argument, while another participant counters that the evidence presented does not convincingly support the concept of intrinsic redshift, suggesting that the interpretations may be overstated.

Areas of Agreement / Disagreement

Participants express disagreement regarding the interpretation of redshift and its implications for quasar motions. There is no consensus on the validity of intrinsic redshift or the analogy presented.

Contextual Notes

Participants reference complex data and peer-reviewed publications, indicating that the discussion may depend on specific definitions and interpretations of redshift and quasar behavior.

twofish-quant
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A non-technical explanation for "FTL" quasar motions

I was trying to think of an accurate but non-technical explanation for quasar motions that seem to be faster than light, and I came up with one.

A have a friend in Atlanta and he sends me a book via UPS. That book takes three days to get to me in NYC. So he wants to visit me and after a day of traveling, he ends up in Philadelphia, and sends me a book from there. Because Philadelphia is closer it only takes two days for the book from Philadelphia to get to me.

Now I'm in NYC, and I wake up one morning and the UPS guy knocks at my door, and he hands me the book that my friend sent when he was in Atlanta. Ten seconds later, another UPS guy knocks at my door, and he hands me the book that my friend sent when he was in Philadelphia.

MY GOD! My friend has magically found a way of getting from Atlanta to Philadelphia in ten seconds! He must have superpowers!

No, that's not what is happening. There's no magic super fast traveling at all. Either when my friend sends a book, or when you see things that seem to be traveling faster than light in quasars.
 
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twofish-quant said:
I was trying to think of an accurate but non-technical explanation for quasar motions that seem to be faster than light, and I came up with one.

A have a friend in Atlanta and he sends me a book via UPS. That book takes three days to get to me in NYC. So he wants to visit me and after a day of traveling, he ends up in Philadelphia, and sends me a book from there. Because Philadelphia is closer it only takes two days for the book from Philadelphia to get to me.

Now I'm in NYC, and I wake up one morning and the UPS guy knocks at my door, and he hands me the book that my friend sent when he was in Atlanta. Ten seconds later, another UPS guy knocks at my door, and he hands me the book that my friend sent when he was in Philadelphia.

MY GOD! My friend has magically found a way of getting from Atlanta to Philadelphia in ten seconds! He must have superpowers!

No, that's not what is happening. There's no magic super fast traveling at all. Either when my friend sends a book, or when you see things that seem to be traveling faster than light in quasars.

Cool analogy. But what does a Postal strike equate to? Absorption by intergalactic dust?
 


Are you kidding? (OP) There is a massive amount of data about quasars, AGNs, redshift, etc. If you choose to believe that redshift=recessional velocity=distance, that's your look-out, but if you want to promote the idea that there is NO evidence for intrinsic redshift, you might want to prepare to defend that notion against peer-reviewed publications that show otherwise.

http://arxiv.org/abs/0805.1492
 


turbo-1 said:
Are you kidding? (OP) There is a massive amount of data about quasars, AGNs, redshift, etc. If you choose to believe that redshift=recessional velocity=distance, that's your look-out, but if you want to promote the idea that there is NO evidence for intrinsic redshift, you might want to prepare to defend that notion against peer-reviewed publications that show otherwise.

http://arxiv.org/abs/0805.1492

As I've pointed to before, there is no compelling evidence in that paper for "intrinsic redshift". Just small number statistics which are over-interpreted by you.
 

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