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 What Function Does Dark Matter or Energy Serve?
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High School For object 3.26 million light-years away, light redshifted by 70 km/s
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Graduate Numerically solving Scalar field coupled to Friedman equation
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High School How could something that is infinite (the Universe) expand?
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High School What does the Universe exapand into?
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Undergrad Calculating the probability that the Universe is finite
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Undergrad What if the Universe expands faster than the speed of light?
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High School Basic confusion about the Big Bang and light cones
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Undergrad Question about the Hubble Constant
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High School Question regarding light from distant objects
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Undergrad An idea for calculating the probability that the Universe is flat
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Undergrad Edwin Hubble and the Evidence for Universe Expansion
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Graduate What assumptions underlie the proof that singularities are inevitable?
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Graduate Relativistic Redshift and understanding it's approximation
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Graduate Peculiar Acceleration - Understanding an Equation
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Undergrad Does Dark Matter Have a Temperature?
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High School Does dark energy's effect or strength vary over time?
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Graduate Deriving EDE Equation: Need Opinions
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Undergrad Please check my calculation of the radius of a finite universe
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Undergrad A relationship between flat vs. finite and (2) Hubble constant tension
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High School What are the potential causes of the universe's eventual demise?
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High School Big Bang: Size of the Universe at Different Epochs
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High School Does dark energy or cosmic inflation explain flatness?
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High School How do the candidates for Dark Energy 'work'?
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Undergrad Could the Universe's Early State Be a Superposition of High and Low Entropy?
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High School Does the CMB itself tell us that it started at 3000K?
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Graduate How Do Recent Studies Impact Our Understanding of CMB Anomalies?
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Undergrad Can the big rip ever be ruled out?
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High School What Space Does the Universe Occupy?
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High School Why doesn't cosmic inflation violate conservation of energy?
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Undergrad Are two-body orbits with a cosmological constant unstable?
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Undergrad Equivalence of Universe Accelerating Expansion?
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High School Accelerating expansion of the Universe
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High School Earth's orbit and the expansion of the Universe
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Undergrad Question about the expanding Universe and the Andromeda Galaxy
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High School What is the relationship between expansion and curvature?
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Undergrad Do all geodesics begin and end at the big bang?
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High School Is the Universe's Matter/Antimatter Asymmetry a Key to Understanding Its Origin?
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Undergrad How long did inflation last in an eternal inflating universe?
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Graduate Calculating the variance of integrated Poisson noise on a defined quantity
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Undergrad Bullet Cluster explained without 'dark substances'
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High School What is the relationship between inflation and the expansion of our universe?
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Undergrad What is the origin of spatial inhomogeneities in the Universe?
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Undergrad EDE - Solving the Klein - Gordon Equation for a scalar field
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Undergrad Is the Anthropic Principle a Logical Explanation or Just Confusion?
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High School Is There a Theoretical Center in a Finite Universe?
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High School Observers sending signals to measure expansion
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Undergrad Is the Hubble constant a constant or is it a parameter?
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Undergrad Cosmology: Compton Drag Explained
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Graduate Hubble Tension and Cosmic Acceleration: A measurement artifact?
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Graduate Is this MOND advance a big deal?
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Undergrad Why aren't Gravitational waves factored in to inflation formulas?
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Undergrad What are the Cosmological monopole and dipole?
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High School No way to catch up with galaxies currently receding at >c?
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Undergrad How well do cosmological models explain the observed µ vs. z data?
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Undergrad What's left to see of the early Universe?
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Undergrad Inflation and size of the Universe
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Undergrad What Are the Origins of the Universe?
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Undergrad Cosmological principle about space and time
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High School Is an infinite universe compatible with cyclic models?
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High School Confused About the Source of CMB Photons: Two Possibilities
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High School According to current physics, is vacuum still something or nothing?
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Undergrad Curvature Index in Flat Universe with Cosmological Constant?
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Undergrad So I wrote a book on cosmology....
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Undergrad On the assumption of an infinite universe
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Undergrad Can someone explain Quasi-steady-state cosmology to me?
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Undergrad What is the acceleration of the expansion of the Universe?
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Graduate Add factor Δℓ or Δℓ^2 in the variance for integrated Shot noise
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High School Are there more theories about the start of our Universe?
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Undergrad The CMB drag on an object moving through space
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Undergrad Is acceleration a more absolute/fundamental quantity in the universe?
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Undergrad What does Causality really mean?
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Undergrad Energy conservation in an expanding universe
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Graduate Introduction of a factor Δℓ when summing equal distants 𝐶ℓ
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Undergrad Is There Evidence to Suggest Our Universe is Anisotropic?
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High School Can we measure acceleration of galaxies and stars?
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Graduate Cl's : sum into a chi^2 when we have a sum of chi^2
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High School Why does MOND fit rotation curves so exactly?
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Undergrad Can magnetic fields explain anomalous galaxy rotation curves?
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High School Traveling to alternate universes
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Graduate Analytical expression of Cosmic Variance - Poisson distribution?
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Undergrad Does a photon travel freely through the CMB photon gas?
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Undergrad Is it time to take the 'bang' out of the Big Bang?
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Undergrad What atoms are we made of, how much is from the big bang?
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Undergrad Shouldn't the Big bang be physically impossible?
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Undergrad Could dark matter consist of primordial black holes?
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High School Please help in explaining 'we are not the center of the Universe'
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Undergrad Did cosmic inflation happen everywhere in the Universe?
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High School Question on paper: Inflationary spacetimes are not past-complete
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Undergrad Acceleration of Universe Expansion: 1/r2
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Undergrad What happened to the range of frequencies after recombination?
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Undergrad Does the CMB reference frame violate the Cosmological Principle?
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High School Can particles interact without a mass?
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High School Do Atoms Expand with the Universe?
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Undergrad Why does particle physics predict cosmo constant is 10^120 too big?
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Undergrad Dark matter and structure formation
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Undergrad An apparently obscure question re dark matter
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Undergrad Is the supply of the observable CMB radiation limited?
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High School What is the Universe expanding into?
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Undergrad What would be the geological consequences of a "big crunch"?
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