A non-technical explanation for FTL quasar motions

AI Thread Summary
The discussion presents a non-technical analogy to explain the perception of quasars moving faster than light, comparing it to receiving books sent from different locations. The analogy illustrates that the apparent speed is not due to actual faster-than-light travel but rather the timing of when the books arrive. Participants debate the validity of redshift interpretations, with one arguing against the idea of intrinsic redshift and emphasizing the need for robust evidence. The conversation highlights the complexity of quasar motions and the challenges in understanding astronomical data. Ultimately, the analogy serves to clarify misconceptions about quasar velocities.
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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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