CMB Anisotropy: Measuring Our Motion Through Space

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SUMMARY

Smoot et al. have measured a dipole and higher order anisotropies in the cosmic microwave background (CMB), which indicates our motion through the universe. The discussion highlights the challenge of distinguishing between motion through space and anisotropic expansion of space. To resolve this, measurements must be taken from two distinct locations: one within our galaxy and another from outside it. This will clarify whether we are moving in one direction or if space is expanding unevenly around us.

PREREQUISITES
  • Understanding of cosmic microwave background (CMB) radiation
  • Familiarity with dipole anisotropy in cosmology
  • Knowledge of observational techniques in astrophysics
  • Concept of frames of reference in physics
NEXT STEPS
  • Research methods for measuring CMB anisotropies from different locations
  • Explore the implications of anisotropic expansion in cosmology
  • Learn about the effects of motion through space on CMB observations
  • Investigate the concept of blueshift and redshift in astrophysical contexts
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Astronomers, cosmologists, and physics students interested in understanding the dynamics of the universe and the implications of CMB measurements on our motion through space.

bwana
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Smoot et. al. have measure a dipole (as well as higher order anisotropies) in the cosmic microwave background. This has been interpreted as our motion through the universe.

so how do we know that the dipole is due to our motion through space and not the anisotropic expansion of space? the only way to know this would be to make measurements from two places that are far apart (one measurement taken within our galaxy and another from outside).
 
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So either we're moving through space in 1 direction, or we're stationary and space is expanding faster on one side of us than the other... ?

It sounds to me like the same thing, just two different frames of reference.
 
right, either we are moving through a spherically expanding space or we are motionless in an expanding weiner. if we were moving through space, shouldn't there be a blueshift in the direction opposite to the redshift behind us?
 

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