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.
Undergrad Is the Brans-Dicke Vacuum Cosmology Theory Still Relevant?
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High School What Does it Mean When We Say the Universe is 'Flat'?
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Undergrad Coordinate dependence of recession velocities
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High School Possibility of Another Big Bang?
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Undergrad How Can the Newtonian Spherical Ball Be in Stable Equilibrium?
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Undergrad Is Big G and Dark Energy Constant Over Time?
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Undergrad How do physicists know that an external world exists?
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Graduate Inflation and measurement of cosmic bodies
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Undergrad In the beginning there was.... a black hole?
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High School Why are there 4 dots in Einstein rings?
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High School Dark matter that doesn't gravitate?
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High School How Does Modern Particle Accelerator Energy Density Compare to the Big Bang?
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High School I don't understand the evidence or possibility of the Big Bang
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Undergrad Is There really a Hubble Tension?
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Undergrad Understanding the Age of the Universe
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Undergrad Finite density at the BB preinflation epoch implies a finite universe?
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Undergrad Is the Pressure Inside a Black Hole So Intense That Atoms Cannot Hold Form?
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High School Other lines of evidence for Dark Energy? (Besides supernova data)
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Graduate Can there be a lawless universe (according to Hawking)?
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Undergrad Cosmology in Crisis Podcast by LSST Scientists
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Undergrad DDO 68: A Young Galaxy Supporting the Steady State Theory
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Undergrad Does the expanding Universe follow Lorentz contraction?
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Undergrad Dark Energy as repulsive gravity
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High School Could Earth's Atmosphere Survive a Close Gamma Ray Burst?
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High School Why The Big Bang banged and didn’t collapsed into a black hole?
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High School Is Dark Energy a Continuous Creation Theory?
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Undergrad Transformation matrix for an expanding space
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Undergrad What is power suppression in CMB experiments?
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Undergrad How Are Heavy Elements Distributed?
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Undergrad How do you calculate the cool-down rate of the Universe?
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Undergrad Some new evidence that the Dark Energy Concept is wrong
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Graduate Why is there no distance-measure in the standard model?
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Undergrad Matter movement versus spacetime expansion
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High School Questions about the cosmic microwave background radition and its discovery
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Undergrad What is the ultimate fate of the Universe?
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High School The observable and non-observable parts of the Universe
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Graduate Does Teleportation to Andromeda Equal Time Travel?
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High School Is Gravity Emergent? Answers to Pre-Big Bang Questions
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High School Who is Ethan Siegel and What Insights Does He Offer About the Universe?
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Graduate Computing sig8 for correction in non-linear regime
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Undergrad Calculating the Maximum total neutrino mass by using cosmological boun
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Undergrad Is Minkowski spacetime a solution of the Friedmann Equations?
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High School How did the universe come into being?
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Undergrad Expansion of space & expansion of matter within space
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High School Infinite Universes: The Science & Limits of the Theory
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Graduate Alfred Nobel Symposium 2005: Energy in Cosmos, Molecules and Life
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Undergrad What is the role of voids in the Hubble tension?
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Undergrad Is everything Lawrence Krauss said about the universe true?
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Undergrad Uncovering the Mystery: What Existed Before the Big Bang?
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High School Universe Discovery: The Finite Theory of the Big Bang and the End of the Cosmos
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Graduate Equation of state of gravitational energy in open de Sitter?
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High School Is the Universe's Expansion Misinterpreted Due to Curvature?
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Undergrad Universe expansion discrepancy vs accelerated expansion
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High School Shouldn't the time dilation in cosmic voids be immense?
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Undergrad How do we determine the ##H_0## from standard rulers and standard candle?
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Undergrad Which redshift value is used in the velocity measurement of distance
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Undergrad Formation of dark matter structures
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Undergrad Loop Quantum Cosmology: Explained in Layman's Terms
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Undergrad How did the initial dust particles form?
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High School How Did the Early Plasma in the Universe Become Hot?
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Undergrad How do we know space is expanding?
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Undergrad What kind of information can we extract from this equation?
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Undergrad Fulvio Melia's new argument for a linear cosmology
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High School Lithium problem in Big Bang nucleosynthesis?
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Graduate Steps on the way to Lightcone cosmological calculator
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High School Why do we assume the big bang created matter/antimatter?
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Undergrad Clarifying the Meaning of Radius of Curvature in Cosmology
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Undergrad New measurement of the Hubble constant is consistent with the CMB value
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Graduate Calculating the Gravitational wave spectrum with Inflation as a source
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Graduate Missing step in the derivation of the Robertson-Walker metric
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Undergrad Why is there a difference between the composition of planets and stars?
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High School How constrained are the initial conditions of the universe?
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Undergrad Cuspy Halo Problem: Questions & Answers
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Undergrad Some questions related to the Cosmological Constant
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Undergrad CMBR and the expansion history of the Universe
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Undergrad What does the cosmic inflation theory actually say about flatness?
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High School Name for the distribution of matter?
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High School Universe expansion rate in m/s^2 ?
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High School We see a quasar 13 billion light years away. What does this mean?
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Undergrad Is Our Universe Finite or Infinite?
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Undergrad The Multiverse and 'No boundary' conditions approach in cosmology
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High School Hip Replacements and Weather Sensitivity
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Undergrad Was the Early Universe as Dense and Hot as a Neutron Star?
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Undergrad Does Euclidean geometry require initial fine-tuning?
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Undergrad Lambda CDM Model and Spatial Flatness
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Undergrad Maximum ##d_p(t_e)## value and its meaning
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Undergrad How can black holes with varying masses have the same extreme characteristics?
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Undergrad Hubble Law & SR: Does Velocity Increase Mass?
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Undergrad Is this explanation of "space itself expanding" correct?
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Undergrad Scale factor from Friedmann's equations
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Graduate Late Photons from the Early Universe?
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High School What parameters of physics are most important to the existence of life?
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Graduate Why isn't back-reaction receiving more study?
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Undergrad What is the current state of research on the nature of Time?
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Undergrad Hubble relation to Scale Factor
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High School A question about the Planck Epoch
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Undergrad Cosmological scale and the pressure of light....
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Undergrad How does BBT resolve away from "It should be a black hole"
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Undergrad Measuring Galactic Rotation: How & What We Know
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Undergrad Does a beginning to time imply absolute speed?
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