Cosmic microwave background radiation

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Discussion Overview

The discussion centers around the cosmic microwave background radiation (CMBR) and its directional properties in relation to Earth and the solar system. Participants explore concepts of asymmetry, homogeneity, and the implications of Earth's motion through the CMBR.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants suggest that there is no universal direction for the CMBR, proposing that various planes (Earth's rotation, Earth's orbit, solar system's orbit) can define different "up" directions.
  • Others argue that an asymmetry is detectable in the CMBR, implying that it may have directional characteristics.
  • One participant mentions the existence of frequency asymmetry and questions whether the CMBR should have a general direction.
  • Another participant asserts that the CMB is extremely homogeneous and questions the expectation of directionality, stating that reflections cancel out.
  • A participant expresses a lack of information and requests detailed resources regarding the CMBR's properties.
  • Links to external resources on CMBR are provided for further exploration.
  • A later reply indicates that measurements of dipole anisotropy can reveal the Earth's motion relative to the CMB, specifically noting a speed of 370 km/s towards the constellation Virgo.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the directional properties of the CMBR, with some asserting homogeneity and others suggesting detectable asymmetries. The discussion remains unresolved with multiple competing views presented.

Contextual Notes

Participants express varying levels of understanding and information regarding the CMBR, indicating potential limitations in knowledge and assumptions about its properties.

Mihael@@/&
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Question>
The fact (simplified) is that our planet is rotating arount the Sun, also our solar system is rotating... Is there available information on direction of CMBR in relation to our planet or to our solar system? THX

foun answer myself



Re: does the cosmos have direction?

--------------------------------------------------------------------------------

There is no sense of "universal direction" at all. You are welcome to use the plane of the Earth's rotation to define the perpendicular direction "up." You're also welcome to use the plane of the Earth's orbit, which is 23.5 degrees different. Or the plane of Sun's orbit around the Galaxy, which is again different. Or the plane of the Galaxy.

You get the idea. There's no preferred direction. There's also nothing different about radio waves, etc. that could be used to
specify one.




Let's start all over again. Is CMBR in one direction or many?
 
Last edited:
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Mihael@@/& said:
Question>
The fact (simplified) is that our planet is rotating arount the Sun, also our solar system is rotating... Is there available information on direction of CMBR in relation to our planet or to our solar system? THX

Let's start all over again. Is CMBR in one direction or many?
Yes. An asymetry is detectable in the CMBR.

This doesn't appear to have anything to do with your previous question, though. Perhaps you could elaborate on what you are asking and how you are trying to connect the two.
 
There is an asymmetry in frequency. Also there should be some reflections, but shouldn't CMBR have one general direction?
 
The CMB is extremely homogenous in every respect and in every direction. Reflections are irrelevant, they cancel out. Why would you expect it to have directionality?
 
I expect it to have directionality probably because I don't have enough information. Just asking is there some detailed information, links, numbers...

:)
 
Last edited:
Thanks mr. Chronos, the answer was there, and it is:
By measuring the amount of the dipole anisotropy (the bluest part of the sky is .0033 K hotter than average), we can determine the magnitude of the Earth's motion with respect to the CMB: the Earth is moving at a speed of 370 km/s in the direction of the constellation Virgo.
 

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