What Are the Time Frame Differences Between Us and Quasars?

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Discussion Overview

The discussion revolves around the concept of time frame differences between observers on Earth and quasars, particularly focusing on the implications of relativistic speeds and time dilation. Participants explore the relationship between the observed behavior of Cepheid variable stars and redshift, as well as the effects of space expansion on time perception.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants suggest that the term "relative time frames" likely refers to time dilation effects due to the high speeds of quasars.
  • There is a proposal that a Cepheid variable star moving away from us at a significant speed would appear to blink more slowly, raising questions about how this relates to redshift.
  • One participant states that time would be significantly dilated for quasars moving at nearly the speed of light, leading to observations of their activity appearing much slower compared to observers moving with the quasar.
  • Concerns are raised about the limitations of current technology in detecting Cepheid variables in distant galaxies, noting that most observed Cepheids have negligible redshifts.
  • Another participant introduces the concept of space dilation, suggesting that the expansion of space itself could affect the perception of time between distant points in the universe.
  • A reference is made to a paper discussing the classical Doppler effect and its implications for redshift and blueshift in quasars, highlighting that relativistic speeds lead to a predominance of redshifts.
  • One participant questions the feasibility of earlier explanations regarding quasar redshifts and discusses the historical context of the quasar controversy and its implications for cosmological theories.

Areas of Agreement / Disagreement

Participants express uncertainty regarding the interpretation of "relative time frames" and whether it pertains to time dilation or space expansion. There are competing views on the implications of redshift and the historical context of quasars, indicating that the discussion remains unresolved.

Contextual Notes

Limitations include the dependence on current technological capabilities for observing distant stars and unresolved questions about the nature of redshift in quasars.

mee
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If quasars are appearing to travel at almost the speed of light from us, what would the relative time frames between us be.
 
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I'm not entirely sure what you mean by "relative time frames", but I think you're asking about time dilation?
 
dicerandom said:
I'm not entirely sure what you mean by "relative time frames", but I think you're asking about time dilation?

Yes that is probably correct.
 
Cepheid

mee said:
Yes that is probably correct.

Would say a cepheid variable star in a galaxy moving at 150,000 mps away from us appear to blink slower and how would this slow blinking, if so, be related to the redshift at which it was detected?
 
Time would be severaly dilated in the case of a quasar moving away from us at nearly the speed of light. This means that we would observe the activity of the quasar as proceeding much more slowly than someone moving along with the quasar.

In theory, a Cepheid variable would appear to vary in brightness more slowly if it were moving away from us at a significant fraction of the speed of light. Unfortunately, the light from any single star is quite feeble, and technology only exists to detect Cepheids only in our own galaxy and, in some select examples, in nearby galaxies. Thus, all Cepheids observed to date have very small, neglibible, redshifts. The technology necessary to resolve individual stars in quasars (which are nothing more than juvenile galaxies) is very far beyond our current technology.

- Warren
 
have a look please at
Kurtiss J. Gordon
Consideration of quasar redshifts
am.j.phys. 48 514 (1980)
 
Or were you asking about space dilation, that is the expansion of space itself between us and very distant parts of the universe?? A rapidly moving distant point appears as chroot describes, but if the distance is so great as to involve expansion of space itself then time not only appears relative but really is.
 
bernhard.rothenstein said:
have a look please at
Kurtiss J. Gordon
Consideration of quasar redshifts
am.j.phys. 48 514 (1980)
For a collection of moving sources with velocities randomly distributed, the classical Doppler effect predicts that half of the sources appear redshifted and half appear blueshifted. When relativistic speeds are involved, the transverse Doppler effect introduces a preponderance of redshifts over blueshifts. In this article it is shown that the size of the effect (i.e., the ratio of redshifts to blueshifts) can be calculated in a straightforward manner. For quasars, redshifts as large as 3.5, corresponding to velocities of 0.91c, have been observed. At this speed, randomly directed motions will produce almost an order of magnitude more redshifts than blueshifts. This consideration should be mentioned in discussions of whether quasars are ''local'' rather than ''cosmological''
(emphasis mine)
So where are the 10% quasars with blue shifts?

This explanation just doesn't fit - it possibly did in 1980, but I certainly would not have considered it feasible back then.

The quasar controversy arose during the 1960's when their observed evolution seemed to put another nail in the coffin of the steady state theory, together with the CMB. Explain away quasar cosmological red shift ("well at that distance they would have to be so bright") and the CMB ("the diffuse light of many galaxies in the far far distance, possibly even in another universe beyond our horizons") and you could still, just about, cling onto a non-evolving universe. However that 'flat Earth theory' eventually lost credibility.


Garth
 

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