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.
Graduate Questions: Gott-Li Can a Universe Create Itself?
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High School What is the oldest of each class of star?
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High School Experimental evidence on cosmological redshift
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Graduate Which galaxies have the best studied evidence for dark matter?
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Graduate Graceful exit of a cosmological inflation model
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Undergrad What does the equation dΩ32 = dr2 + r2dΩ22 mean in terms of flat space?
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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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