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 What Are the Key Statistics in the Evolution of Stars Over Billions of Years?
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Graduate Universe Expansion: Is Merging Possible?
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Graduate Misalignment of angular momentum of stars (simulation)
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Graduate What happens when matter pops into and out of existence at Planck length scales?
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Graduate What happens to the gravitational energy of a cooling brown dwarf galaxy?
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Graduate Quantum Gravity: Photons, Electromagnetic Radiation & the Universe
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Graduate Zero-Energy Universe Hypothesis: Questions & Answers
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Undergrad Expanding universe, big bang question
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Graduate Are the Parameters for Calculating the Age and Size of the Universe Different?
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Graduate Expansion by doppler (red) shift
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Graduate Does Gravitational Time Dilation Impact Cosmological Age Estimates?
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Graduate The big crunch effect on entropy and time
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Graduate Unraveling the Mystery of Dark Energy in the Expanding Universe
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Graduate Can Dark Matter Radiate Heat or Form Black Holes?
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Graduate Dark Matter. Space-Time curvature. Galaxy formation
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Undergrad Is a black hole black from all directions?
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Graduate Can the universe be both infinite AND expanding
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Graduate True map of universe from computer simulation with CMB initial state
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Graduate Is there radiation colder than the CMBR?
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Graduate Why is the CMB Visible if Younger Light Sources Are Not Yet Visible?
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Graduate Our universe may have emerged from a black hole in a higher-dimensiona
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Graduate Energy of an Expanding Universe Decreases?
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Graduate Dark matter = ligh energy, Dark Energy = also light energy?
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Graduate Is the big bang actually a white hole?
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Graduate Origin of Dimensions: Evidence of Order or Big Bang Simultaneity?
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Graduate Question regarding the universes origin
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Graduate Infinite universe but finite beginning?
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Graduate Gravitational effect of virtual particles
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Graduate Can black hole entropy be observer-dependent?
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Graduate How many gravitons are there in the observable universe?
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Graduate Variational Principle for Spatially Homogeneous Cosmologies/KK-theory
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Graduate What happens to the energy when the universe dies out?
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Graduate Does Inflation Theory Exclude the Impact on Temporal Dimension?
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Undergrad Any dates/venues of lectures in the UK?
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Graduate Black Holes in the center of galaxies
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Undergrad Questions about the structure of the universe
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Graduate Initial conditions for tensor perturbations
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Graduate Holographic principle in reverse
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Undergrad Galactic Habitable Zone Theory: A Physiologist's Inquiry
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Graduate Can the Boltzmann equation accurately predict the relic density of dark matter?
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Graduate Dark Energy/Matter: Why Does It Make Sense?
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Graduate Lay-ish approach to *both* Friedman equations (2nd try)
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Graduate A speculative explanation why universe accelerates
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Graduate Is There a Maximum Distance Limit in Our Universe?
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Graduate Questioning 3D Model views of effect of large bodies on curving space.
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Graduate Passing of time in Bolzmann's entropy curve. Is it all wrong?
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Graduate Expansion, redshift, and conservation of energy
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Graduate Does the Existence of the Axis of Evil Mean a Special Frame of Reference?
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Graduate Light Cone - Hubble Radius & Time T and R Relationship
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Graduate What is "empty space" composed of?
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Graduate Problem in Dodelson Modern Cosmology
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Graduate Big Dipper Cosmic Ray Hotspot Homogeneity question
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Graduate Were the first stars much larger and shorter-lived than our sun?
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Graduate Expansion of Space vs Velocity in Space
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Graduate FRW cosmology [itex]Ω_{Λ}[/itex] domination
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Undergrad Are We Also Expanding with the Universe?
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Graduate Why the Universe is accelerating as it is expanding
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Graduate How many infinite universes can fit within a multiverse?
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Undergrad What is the basis of Rotation Curve?
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Graduate Cosmology, Quantum fluctuations,and entanglement
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Undergrad Is There a Simple Equation for Hubble's Constant and Time in Astronomy?
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Undergrad Why didn't the big bang just become a black hole?
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Graduate Decoupling condition for dark matter WIMP
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Graduate Chronology of recessional velocity
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Undergrad Can the Sun's size affect the orbits of planets around it?
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Graduate Why should the universe succumb to our measurments
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Graduate Infinite Universe: What does it mean?
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Graduate Dark Energy: A Total Nuisance to Physicists?
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Graduate Reason the early Universe was opaque?
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Graduate The Probability of an Infinite Universe
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Graduate Size of Universe at CMB last Scattering
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Graduate Acceleration of Universe: Friedmann Equations
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Graduate Proof of/Reason for SVT Decomposition
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Graduate Boundaries of Time in The Evolution of The Universe
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Graduate Does the Block Universe Theory Suggest Time and Motion Are Illusions?
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Graduate What is the relationship between the Hubble radius and the age of the universe?
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Graduate How Can the Big Bang Occur Without Time?
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Graduate Boltzmann equation for photons
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Graduate Discover the Relationship Between CMB's Temperature and Redshift z in Cosmology
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Graduate Was the expansion of the universe always greater than c?
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Graduate Scalar field in Expanding Universe EOM
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Graduate Couldn't the universe be finite if Omega =1?
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Undergrad Will the Universe Shrink and Reignite Life?
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Graduate Is dimensionless singularity truly dimensionless?
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Graduate Did Matter Exist Before Time? - Hartle-Hawking State
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Graduate Gerald Shroeder and the age of the universe
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Graduate Matter vs Anti-Matter: What Survived the Big Bang?
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Graduate The black Hole Wars - Losing Information in the Hawking Radiation
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Graduate 2-point correlation functions for curvature perturbations
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Graduate Mass required for a closed universe.
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Undergrad Astronomers Measure Hubble's Constant at 68 km/s/Mpc | Space.com Study
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Graduate Must (Ve) expansion of the universe be C?
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Graduate Implications of the divisibility of time for the study of the big bang
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Graduate Final State of the universe 10^ googal plex^ googal?
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Simulated Universe: Who or What is the Creator?
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Graduate Closed Universe? Local H0 Measurements & Relativistic Corrections
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Undergrad DECIGO: Launch Date & Funding Status
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Graduate Gravitational attraction on the cosmic scale?
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Graduate Is the Universe's Shape Spherical or Hyperbolic?
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Undergrad Is the CMB a Distorted Image of the Early Universe?
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