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.
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Insights Intro to Big Bang and Infinity Concepts - Comments
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Insights Equations of State for Photon Gas and Relativistic Electron Gas
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Insights A Journey Into the Cosmos - FLRW Metric and The Friedmann Equation - Comments
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High School Infinite universe, infinite volume from the beginning?
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Undergrad Hubble Constant, Dark Energy and the Expanding Universe
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20
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High School Independent Inflationary Regions in an Infinite Universe?
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Undergrad Age of the Universe and the Cosmological Constant
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Undergrad A paper regarding the Hubble tension using Gaia data
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3
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High School A Mind-Boggling Number Comparison
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High School What is space?
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Undergrad Is Vacuum Decay from a False to True State Impossible or Just Unlikely?
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Undergrad Milne vs. Minkowski metric
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Undergrad Comparing different scale factor functions in the same graph
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Undergrad Does the scale factor need to be normalized?
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Undergrad Blueshift in case of the Big Crunch scenario
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Undergrad Are Boltzmann brains predicted by our current cosmological theories?
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High School Expansion and raisin bread
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High School Questions about the structure of dark matter
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Undergrad Merely a thought of where the universe expands into
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High School Estimates — True Size of the Universe?
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Undergrad Before the Big Bang
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Undergrad Galactic collision and dark matter
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Undergrad Do existing EFE solutions support Closed Timelike Curves?
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Undergrad The quintessence as variable dark energy
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Graduate Couldn't the cosmological constant also have some sort of "dynamics"?
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High School Red shifted tired light doubts
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Graduate Strong Progenitor Age Bias in Supernova Cosmology
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High School If the Universe has a cause, what caused that cause?
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High School Looking to get a better understanding of bubble universe formation
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High School Is space stretching or is new space being created?
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High School Rutgers finds a transparent Einstein Cross - apparently a dark matter "halo"
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Undergrad Questions about quantum cosmology
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Undergrad Where did the early photons go?
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High School Can big bang be a part of a loop?
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Undergrad Are primordial fluctuations the source of all structure?
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High School What happens to information inside a black hole?
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Undergrad Illuminating Black Hole Shadows with Dark Matter Annihilation
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High School Matter density right after the decoupling
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High School Inflation after Atacama Cosmology Telescope Results
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High School Realism about singularity
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Undergrad Cosmological perturbations and CMBR anisotropies
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High School What is conformal time?
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High School Cosmic Microwave Background Stage 4 Cancelled for now
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Undergrad Is Introducing a New Cosmological Model Based on Aether Theory Permissible Here?
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Undergrad No symmetries in the Universe at the Big Bang...?
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High School Flatlander analogy of spherical surface as observable universe
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High School Conflict between the conservation of matter and the rapid expansion of our universe
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Undergrad The impact of early galaxy formation on the CMBR
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High School Big Bang and Infinite Universe
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Undergrad How to calculate the mass within the Hubble Sphere?
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Graduate Hubble tension -- any resolution?
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High School Can You Ace Harvard's Galactic Quiz?
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Undergrad Dark Matter , Dark energy and the Dirac equation
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Undergrad Cosmological Redshift and Expansion
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High School Could Black Hole Collisions Trigger a Cyclical Big Bang and Universe Rebirth?
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High School Thought experiment to compare the present with the future flow of time
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High School Proper time of the observer resting in CMB reference frame
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Undergrad How do you get to the conclusion that there is accelerating expansion?
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Undergrad Inflation Models that don't produce Multiverse?
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High School What Would You See at the Edge of the Expanding Universe?
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High School Does an infinite universe contradict a Big Bang origin?
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Undergrad Is the amount of dark matter constant in the Universe?
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Undergrad If white holes were to exist in our Universe
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Graduate Black Hole TON618 - Wavelength Spectrum
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Graduate Late time and early time approximation for EOS
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Undergrad Will DESI confirm that the Universe isn't described by the ΛCDM model?
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Undergrad Questions on the consequence of an evolving dark energy parameter
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High School Dark Matter Theory Endorsed By NASA
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Undergrad Resolution of Peeble's ODE equation
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High School An old spin to our Universe
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Undergrad Early large galaxy studies
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Undergrad Question about Tong's cosmology lecture notes eqn. 1.19
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High School Could you build a container to isolate cosmic radiation?
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Graduate What does it mean to model the distribution of galaxies as cosmic dust?
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High School How do we know if a distant galaxy is matter or anti-matter?
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High School Questions about the Eddington Limit and Super - Eddington black holes
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Graduate Models without dark energy
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Graduate Is there a stretching of the light curves of supernovae 1a?
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Undergrad 3 questions about a paper on density fluctuations in the Universe
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High School Evolution of the Universe in reverse
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Graduate Interpretation of an anticorrelation between 𝐻0 and log10(𝜔𝐵𝐷)
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Undergrad The Boundary of the Observable Universe
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Undergrad Do particles leave behind an image when crossing cosmo event horizon?
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Undergrad How would the laws of thermodynamics change in a contracting universe?
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High School Cosmological Redshift in Simulated Universe
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Graduate Form of energy at time of big bang
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Undergrad Why do we still see the CMB today?
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Graduate Black hole thermodynamics and accelerated expansion
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Undergrad Two-dimensional negative curvature space
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High School Redshifts of nearby galaxies
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Undergrad The Universe is expanding with acceleration
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Undergrad Distance at redshift z=0.666
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Graduate Dark matter is running out of places to hide!
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High School Galactic Sheets and Voids
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Undergrad Bose-Einstein and Fermionic condensates in space?
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High School How can an infinite universe expand?
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Undergrad What if the early expansion of the Universe was not so rapid?
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Undergrad Does the amount of hidden mass remain constant?
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High School Do Fictional Worlds Exist in the Multiverse?
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High School Questions about a paper on reconciling JWST and HST data
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Undergrad How we are in a matter dominated universe (without antimatter annihilation)
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Undergrad Toward the spectral index in slow roll
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Undergrad Density fluctuations in a homogeneous linearly expanding universe?
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