A Quasar Based Search for Hypertorus Cosmology Dylan Menzies, Grant Mathews University of Notre Dame

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A Quasar Based Search for Hypertorus
CosmologyDylan Menzies, Grant
MathewsUniversity of Notre Dame
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Cosmological 3D Topology

• General relativity says nothing about topology.
  Maybe 3D topology is not simply connected.
• Imposing a non-trivial topology can make a
  non-compact universe compact.
• In flat space 10 compact topologies are possible.
• Infinite non-zero compact constant-curvature
  topologies.
• Topological dimension scale?

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The Hypertorus

• 2-torus covering space
• globally homogenous

3-torus fundamental domain
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Hypertorus Evidence

• WMAP quadrupole and octopole
• Suppression and alignment Tegmark et al march 03
• Hypertorus?
• Use to guide search (l,b) (250,60)

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Multipole Suppression
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Previous Results

• 2D CMB methods
• Multipole suppression, dT3 ? 0.25 dSLS
• Cornish circles, de Oliveira-Costa July 03, rules
  out T3
• Search for discrete modes could find dT3gt1 dSLS
• eg Rocha 02 Weak bounds so far.

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Previous Results

• 3D quasar groups
• Bounds weaker dT3 ? 0.02 dSLS
• Reliant on redshift
• Dropout intolerant

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z-free test

• Locate axis without z
• Bidirectional
• search up to dSLS
• Find direction pixels with high number of
  alignments.

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More Filters

• Based on lambda .7 - .1, flat (WMAP)
• Exclude pair if t1-t2 gt .5 billion yrs
• (reduces peculiar velocity error as well)
• Exclude if z1, z2, theta1, theta2 not well
  related.

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z-distance relation

• d

z
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Pixel Track Illustration
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More Sensitivity

• Bin by calculated dT3, store max alignments and
  location of max in each bin.
• Repeat on several sets decorrelated by random
  z-redistribution. Use mean and deviation of the
  bins in these sets as null hypothesis.

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Results

• 0.01 deg resolution, 20x30 deg search
• dT3 bin spacing 0.002 dSLS
• 2nd peak suggests dT3 .38 dSLS,
• axis (273.7, 59.1)
• But decorrelated data not consistent.

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Results

• Sensitive to dropout of below 0.01 over much of
  dT3 range