Cosmology Forum

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Join in expert discussion on topics revolving around cosmology. Cosmology is the origin, evolution, structure and eventual fate of the universe.
High School Questions about dark matter, matter and elements
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Undergrad The Acceleration and the density of galaxies
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High School Accelerating Universe Expansion: Age & Hubble Constant
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Undergrad Slow-roll Inflation and Horizon Problem
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Undergrad Dimensions of Cosmic Scale Factor ##a(t)##
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Graduate Relation between Matter Power spectrum and Angular power spectrum
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Graduate Expression of the mean and variance of spectroscopic Shot Noise
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High School What happens to time as space is expanding?
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Undergrad Temperature of the Universe based on the ΛCDM Model
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Undergrad Can a Homogeneous Universe Avoid a Big Crunch?
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Undergrad Implications if New Dark Matter Maps are Correct?
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High School Cosmological constant for the Universe's expansion
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Graduate New Dark Energy Map Challenges Einstein's Theory
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Graduate Cosmological gravitational waves
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Undergrad New H0LiCOW result: Hubble constant is 73.3 +1.7-1.8 km/(s*Mpc)
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Graduate Fourier transform and Cosmic variance - a few precisions
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High School Feasibility of multiple "big bangs"
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Undergrad Dark energy is intrinsic to the space itself
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Polling for estimates of probability our universe is infinite
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Undergrad Black Hole Diameter: Is It Finite or Infinite?
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High School The Fate of the Universe -- Expansion or Collapse?
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Undergrad What Is the Difference Between Spacetime Curvature and Spatial Curvature?
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Undergrad Proton decay at the end of the Universe
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Undergrad The Hubble constant − constant in what way?
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Undergrad How long would it take the Universe to generate an Earth-like chemistry?
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Undergrad Spatial flatness and cosmological constant
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Graduate What Do Planck 2015 Results Reveal About Power Law Potential Models?
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Undergrad Changing curvature as a universe evolves
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Undergrad Some questions about baryogenesis
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Graduate Angular power spectrum dependence in redshift z and k
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Undergrad Is the Isotropic Universe Truly Centerless?
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Do relativistic effects make the age of the universe moot?
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High School Question about "our observed universe"
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Graduate Looking for sources of information on Black Holes
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Undergrad How Does a CMB Photon Travel Through Expanding Universe?
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High School 2D Model of the Universe as an expanding ball
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Graduate Quintessence field equation of state
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High School Gravitational fields affecting each other?
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Undergrad New Paper Claims Primordial Black Holes Don't Explain Dark Matter
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Undergrad Penrose's Latest Paper on CCC: Evidence or Wishful Thinking?
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Graduate Distances between observers using the Lightone7 calculator
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Graduate Discrepancy in Jorrie’s LightCone7-2017-02-08 Cosmo-Calculator
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High School Request for an up to date list of cosmological theories
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High School A question about which Cosmology theories are mainstream and how?
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High School Early Universe Radiation: Gamma to Microwave?
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Undergrad How Do Inhomogeneities in Matter Affect Cosmic Evolution and Backreaction?
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Undergrad Questions about Isotropy in Our Universe and Implications
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Undergrad How to compute the expansion of this congruence?
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Undergrad What is the current status of the Hubble-tension?
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Undergrad When was the matter density equal to the vacuum energy density?
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Graduate What are the parameters that are the same in CMB data for multiple models?
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Undergrad What are the key characteristics of rivals to inflation in cosmology?
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High School How can the Observable Universe be a closed system?
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Graduate Combining 2 probes in order to increase Figure of Merit
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High School The Universe is now closed and curved?
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High School Does Dark Matter Have a Periodic Table?
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Undergrad Are masers orbiting black holes a reliable standard ruler in cosmology?
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Undergrad Is dark energy pushing or is it a mirror concept of gravity?
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Undergrad Accelerating Universe and spherical distribution of matter
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High School Did the Big Bang expand faster than light?
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High School Can We See Beyond the Voids in Our Universe?
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Graduate What is the jerk parameter in terms of the Density parameters?
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High School The infinite and the infinitesimal
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High School An interesting consequence of the closedness of the Cosmos
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Graduate Black Holes Formalism: Overview of Misner Sharp Mass
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High School How can dark energy comprise 74% of the Universe?
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Undergrad Is Scale Factor Continuity and Differentiability Necessary?
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Undergrad Laws of physics from initial conditions?
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Undergrad Is there any inflationary model without a fundamental theory?
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Undergrad Is there a Friedmann equation form with inflation?
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High School Did the Big Bang follow multiple bangs? How did matter come to collide?
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Undergrad Change law of gravitation to remove dark energy and dark matter
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Undergrad Contradictory Cosmological Values: Crisis for Cosmology?
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Undergrad What is the best current value for Omega_r?
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Graduate An article on Big Bang theory contradictions
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Undergrad Question about spacetime singularities
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High School How does the cosmological constant affect gravitational collapse?
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High School Dark matter interactions other than gravity
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Undergrad Cosmology Comoving coordinates and observers
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Undergrad Demonstration of comoving volume between 2 redshifts
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Undergrad Big Crunch and the Universe's shape
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Undergrad How does the Singularity produce all the diverse matter in the universe?
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Undergrad Does Hawking Radiation Cause Black Holes to Evaporate?
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High School New theory of the early Universe
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High School Question about calculating the density of the Universe
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High School Difference between an Einstein frame and a String frame?
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Graduate BGV-theorem and Penrose's Conformal Cyclic Cosmology
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Undergrad Schwartzchild radius and the Big Bang
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Undergrad Reason for matter rather than antimatter?
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Undergrad What "space" is used in defining cosmological distributions?
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Undergrad Qs re the behavior of atoms after decoupling completed
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Graduate Confusion in Angular diameter distance
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Graduate Are topological defects such as domain walls really discontinuous?
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Undergrad What is the density of hydrogen atoms in the Universe?
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Graduate Experimental test of shrinking matter theory?
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Undergrad Multiple Universes Coming into Contact
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High School Is the Big Bang only about the observable Universe?
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Undergrad New Hubble Paper On Lensing In Galactic Clusters
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High School Questions about the Curvaton particle
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High School Finding the present day distance to a galaxy
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