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 if the universe's expansion is actually slowing down?
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Undergrad Cosmological constant and rate of expansion of the universe
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High School Is Scale Invariance the Key to Understanding the Expansion of the Universe?
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High School Implications of gravitational waves from the Big Bang?
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High School Could time move inside a black hole?
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Undergrad Could the Big Bang's Location Be Defined by Gravitational Forces?
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Undergrad Could dark matter be just too reflective?
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Undergrad How does the speed of light affect expansion acceleration?
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Undergrad Is There an Extra Time Dimension in Paul Steinhardt's Cyclic Model?
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Undergrad What is the universe expanding into ? Eternal inflation
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Undergrad Does Entropy Change on Horizons?
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Undergrad How to derive number of nucleons in Universe?
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High School Can somebody help me understand singularities better please?
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High School Decoding Dark Photons: Gauge Symmetry in the Dark Matter Sector
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Graduate Is the Higgs Field Vacuum Energy Density Negative?
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High School How Large Is the Entire Universe?
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Undergrad Difference between oscillatory/cyclic model and big bounce?
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Undergrad Equilibrium of Universe: Earth vs. Black Hole
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High School Calculating Average Time for Travel Using Acceleration and Velocity
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High School Where Did All the Matter in the Universe Come From?
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Undergrad Angular momentum of the Universe
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Undergrad Cosmological constant problem, interesting solution?
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High School Does a gravitational wave change the speed of light?
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Undergrad Is the Three-Dimensional Universe Explained by Knot Theory?
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Undergrad Number of galaxies in the Universe
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Undergrad Is Inflation unlikely or likely?
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Undergrad The Expanding Universe: A Scientist's Perspective on Infinite vs Finite Space
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Undergrad Why does Hubble sphere expand with time?
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Undergrad Understanding the 2nd Term of the Friedmann Equation: Replacing U with -kc^2
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Undergrad Why is the Matter+Lambda Universe Equation Equal to 1-Ω?
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Graduate Quantum fluctuations of the metastable false vacuum
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Graduate Is gravitational constant unchanging over age of universe?
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Undergrad Dark Energy and the Cyclic Universe?
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High School Explain Dark Matter: Verlinde's Theory Tested
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High School What is dark energy in the fabric of space-time?
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High School They found some missing mass, Hideki Tanimura Institute of S
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Undergrad Galaxy Rotation Curves and Mass Discrepancy
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Undergrad Where Does the Cosmic Microwave Background Come From and How is it Measured?
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Undergrad Dark Energy Not Constant: New Claims
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High School Quantised Inertia: A Solution to Dark Matter and Galaxy Rotations
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High School Black holes in the centres of galaxies
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Undergrad Expanding universe and quantum wavefunctions
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Undergrad Did Phase Transitions Drive Inflation in the Early Universe?
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Undergrad T-symmetry and WDWE with regards to a Universe from Nothing
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Graduate Press Schechter function -- the variance on mass scale
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Undergrad Dark matter/energy, why must it be there?
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Undergrad Is the speed of gravitational waves non- dispersive?
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High School Does gravity self interact with itself
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High School Does this paper disprove the possibility of a new universe creation?
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High School Does the Expansion of the Universe Affect Gravity?
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High School Expansion Propagation: Finite Seed vs Everywhere?
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High School How can the Big Bang model apply to the entire universe?
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Undergrad Understanding the Role of a(t)*dr in Calculating Actual Distance
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High School Big Bang theory and the known universe
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High School What is the age of the universe relative to?
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High School Did the big bang create something from nothing?
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High School Is Our Observable Universe the Actual Size of Our Universe?
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Graduate Definition of [itex]\sigma_8[/itex]
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Undergrad Why not detect dark matter in our own galaxy?
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High School Are Gravitational Waves accepted?
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Undergrad Observable Universe Size in Different Perspectives
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High School Age of the universe: observable or entire universe?
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Undergrad Hawking radiation from de Sitter horizon
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High School What if we weren't the only Big Bang
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Graduate GADGET2 Simulations: Fixing N-GenIC Error
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Undergrad Influence of Dark Energy and curvature in photon-baryon fluid?
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Undergrad How fast is the Universe expanding?
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Undergrad Why isn't the Planck-scale limit taken as a postulate?
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Undergrad Is the Planck length a proper length?
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Undergrad Finding Remnants of the Big Bang
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Undergrad Dark energy and conservation of energy
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High School Is there a unity across scale in the universe?
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Undergrad Perlmutter presentation : pb on the age of the Universe
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High School How to debunk the idea we are the center of the universe
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Undergrad IOAA 2nd problems: universe expansion
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High School How to do the calculations showing the Universe is flat?
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Undergrad Galaxies moving away at the speed of light?
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High School Angular momentum, degeneracy pressure, and cosmic inflation
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High School Big Crunch, Big Bang and information loss
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High School Does observation *Determine* the past?
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High School Pulsar Beams: Spin, Wobble, & Projection
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High School Why are only hydrogen and helium created
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High School Do we exist within a singularity
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High School Why didn't the Universe end up in a huge black hole?
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Undergrad A copy of me in an infinite universe
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Undergrad No detection of gravitational radiation
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Undergrad Planck length and space expansion/contraction
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Undergrad Why is inflation initial patch length ~ 1 Hubble length ?
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Undergrad Why the GUT epoch ended at ~10^-36 s ?
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Undergrad Inflation: meaning of χ (chi) for time scales?
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Undergrad Inflation lecture from Guth : why does d(ρ)/dt = 0 ?
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Undergrad Are photons from the CMB being emitted from beyond our cosmological horizon?
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Undergrad Why hasn't the light from the CMB already passed us?
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Undergrad The particle horizon value is ignoring inflation?
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Undergrad What is the C_l in the Fisher Matrix For An CMB Survey?
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High School Did Mass Exist in the Early Universe Before the Higgs Boson?
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Graduate The Big Bang model only deals with the known universe - True or False?
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High School Could dark matter and dark energy be the same thing?
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Undergrad Propagation of a light ray : Multiply or not by factor
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Undergrad The Big Bang: Exploding the Myth of a Center in Space and Time
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