The class project is a joint effort to compile observational constraints on the values of the fundamental cosmological parameters.

Each of you will choose a cosmological parameter on which to report. Which one is up to you, but you must discuss your choice with the instructor in advance (by Tuesday 19 November at the latest). Some examples of possible topics are given below. There should be a bottom line, like H₀ = 70 or Ω_m = 0.25 (along with error bars, of course). Joint analyses are forbidden: letting Planck tell us all the answers at once defeats the purpose of this exercise, which is to check if all the available data point to the same set of cosmological parameters.

You will make a 5 minute oral presentation to the class. Write a title and abstract (1 paragraph) on the result as if you were the author of the paper who is going to present it at a meeting. The written abstract is intended for the other conference attendees - in this case, your classmates - and are due Tuesday 26 November so that they can be posted in advance of your talks on December 3 and 5. They will be posted as part of a schedule of talks so that your audience can read them in advance like abstracts at a conference.

A complete draft of your presentation file is also due on Tuesday 26 November. Last-minute updates are allowed, but a complete draft needs to be submitted before Thanksgiving. Submitted files will be organized on a single computer to minimize switch-over time between speakers.

Topics to Investigate: Observational Constraints

• H₀ from direct measurements (e.g., Riess et al. 2022 or Freedman et al. 2024).
• Age constraints [f(q₀,1/H₀)] from globular clusters (e.g., Valcin et al. 2020 or Ying et al. 2023).
• Ω_b from the light element abundances (e.g., deuterium, helium, lithium)
• Ω_m from
  • kinematics
  • large scale structure (e.g., 2dF; 6dF);
  • cluster baryon fractions (e.g., Evrard)
  • cluster mass-to-light ratios (e.g., CNOC)
• See the more general list of topics below for more ideas.

More Topic Ideas

Parameter Estimation

• Hubble Constant, Specific Distance Indicators and their Calibration
• Age (globular clusters, high-z galaxies, nucleochronology, etc.)
• Omega
• Deceleration (see also classic tests)
• Lambda
• "Concordance"

Classic Tests

• Standard Candle (e.g., SN Ia)
• Standarad Rod (e.g., radio lobes)
• Count-magnitude
• Count-redshift
• Tolman test

Large Scale Structure

• Voids, Walls & Filaments
• Bulk Flows
• Clusters (abundance, bias, baryon fraction, gravitational lensing, etc.)
• Power Spectrum; Shape Parameter
• Structure at High Redshift
• The Hubble Deep Field(s)

Microwave Background

• Power Spectrum
• Temperature measurements; dipole and quadrupole
• Space missions, past & present: COBE, MAP, & PLANCK
• Structure Formation
• Joint cosmic parameter estimation, "cosmic complimentarity"

Primordial, or Big Bang Nucleosynthesis (BBN)

• Deuterium from QSO absorbers
• Helium from HII Regions
• Lithium from metal poor stars

Dark Matter

• Hot Dark Matter (e.g., massive neutrinos)
• Cold Dark Matter (WIMPs, Axions; structure formation)
• Baryonic Dark Matter (missing baryons; brown dwarfs, MACHOs)
• Alternatives to Dark Matter (conformal Weyl gravity, MOND)

Alternative Cosmologies

• Steady State
• Chronometric
• Plasma
• MOND
• Weyl
• Brans-Dicke
• Quintessence, X-matter