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 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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The Big Bang: Exploding the Myth of a Center in Space and Time
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Undergrad Understanding the Early Chronology of the Universe
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Undergrad Equilibrium chaotic environment
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Graduate Help With Constraining Parameters in Massive Gravity Action
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Graduate Fisher Forecasting For EUCLID Survey Help
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Undergrad New possible explanation for Hubble redshift
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Undergrad Radial BAO size method and Hubble parameter
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Undergrad Don Page - cosmological doomsday argument
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High School ? about oscillating models of the Universe and Entropy
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Undergrad Information for black hole region in surface surrounding it
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Undergrad Black hole - between horizon and singularity
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Undergrad Black hole - event horizon and Hawking radiation
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Undergrad What is the Cosmic Microwave Background and how can we observe it today?
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Undergrad Question on the particles that formed the Earth.
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Undergrad Infinite Regress: Cosmologists' Answer to the Dilemma
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High School Measurements on the entire universe
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High School Is Inertia Tied to the Stars According to Mach's Principle?
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Undergrad Why Does Physical Space Have 3 Dimensions?
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Undergrad What is the significance of systematic redshift and Mg II in astrophysics?
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High School Is the concept of a multiverse just science fiction or a scientific possibility?
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Undergrad Time Scale -- Does Time have uniform Scale?
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Insights What Is the Cosmic Background Radiation?
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High School Nothing, something and the Universe
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Undergrad Problem interpreting a Distance-Redshift Plot
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Undergrad Neutrino flavour eigenstates and expansion of the universe
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Undergrad Comoving distance and redshift relationship derivation
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Undergrad Experimental bound on the scalar spectral index
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High School Could Our Location in a Supervoid Alter the Hubble and Acceleration Parameters?
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Undergrad Why Aren't Galaxies Formed After the Big Bang Referred to as Being Further Away?
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High School Why is the low entropic state of the early universe a puzzle
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High School Did we just discover the Milky Way is in middle of nowhere?
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Undergrad Possible retrocausal events and time paradoxes
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High School Hubble's constant and Minkowski spacetime
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Undergrad Red shift and the maths for gravity
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Graduate How To Do Fisher Forecasting For Constraining Parameters
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High School Relationship Between Density and the Hubble parameter
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High School Our solar system and its fellows
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High School Understanding Re-entry Perturbations After Inflation
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High School What Drives the Accelerating Expansion of Space?
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High School Singularities forming universes?
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Undergrad Why does physical space have to be three-dimensional?
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Undergrad Does the Planck length expand in a FRW universe?
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