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 How do we calculate galactic gravitation?
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Undergrad Liouville Theorem and the Expanding Universe
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Undergrad Would complexity re-emerge if cosmic expansion reversed?
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Artistic sense-ualisation of elementary origins of the Universe
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High School Is Dark Energy Causing the Universe's Expansion?
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Undergrad Positive energy density of the universe
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Undergrad List of modified gravity theories
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Undergrad How much does the Universe accelerate?
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Undergrad What would happen if dark energy density decreased?
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Undergrad Gaia parallaxes might reduce tension for Hubble constant
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Graduate Numerical solution of the Mukhanov-Sasaki equation
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Undergrad Ratio of Normal to Dark Matter: Unchanged Since Beginning?
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High School Why Does Cosmic Growth End and Why Is Our Era Unique?
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High School Is the cosmic expansion uniform everywhere?
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Undergrad What formulas would apply during a Big Crunch
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High School A Valid Position on Time Theory?
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High School What is containing the Universe?
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Undergrad Question on the Derivation of Temperature/Scale Factor Relation
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High School Measuring the Universe's expansion rate
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Undergrad Possibility of a quasar jet laser impacting Earth directly
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High School What would the universe be like with less mass and energy?
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Undergrad Universe Expansion: Growing or Stretching?
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Undergrad Time dilation vs. the Doppler effect
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High School Conundrum thinking about crossing an Event Horizon
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High School Do we directly observe redshifted galaxies receding >c?
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Undergrad Communicating about the LHC and Cosmology in a creative way?
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High School Relationship between the age of the Universe and the Hubble horizon
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Undergrad How can there be fluctuations in the inflaton field value?
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High School How Does Age and Distance Affect Light from Distant Galaxies?
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High School Extrapolation back to T zero, before 1980
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Undergrad Does the Planck Length Experience Length Contraction at High Speeds?
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Undergrad CMB results cause the contradiction of big bang theory
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High School Where Does the Energy for the Expanding Universe Come From?
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High School What is the cause of Cosmological redshift?
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Undergrad Conservation of energy in an expanding universe
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High School Dark Energy Fluids: Read the Latest Research
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High School What are these diagrams showing about GR?
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Graduate Current Status of Eternal Inflation
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Undergrad Understanding Penrose's large number
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High School Is the Universe Actually Infinite? A Philosophical Discussion
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Undergrad ....Alternatives to Inflation in Primordial Power Spectrum
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Undergrad Is any attention being given to Conformal Cyclic Cosmology?
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High School Standard Big Bang model vs Inflationary model
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Undergrad GW170817: Limits on D>4 Spacetime Dimensions
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Undergrad Testing Inflation: A Definitive Test & Laymen Explanation
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High School Density of the early Universe contributing to the red-shift?
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Undergrad What is it that forces an object down curved space time?
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Undergrad Zero Active Mass in FRW cosmologies
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Undergrad What is the Janus Universe and its implications for the arrow of time?
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High School What is Olbers' Paradox and how does it relate to the universe's structure?
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Undergrad Is the expansion actually accelerating? Or does it just appear so?
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High School Is the Universe a 3D Cut of a 4D object?
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Undergrad Positions of distant supernova explosions false?
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Undergrad Is the universe actually just mass and length?
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High School Questions About the Growth of the Universe
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Undergrad What is the purpose of Cosmology and where can I find information about it?
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Graduate What volume of interstellar space is needed to form a star?
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Undergrad Is Dark Matter Really a Cold, Collisionless Fluid?
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Undergrad BAO : Relation between redshift, Hubble constant and radial
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Graduate Solving WIMP & Dark Matter Equation
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High School How Long After the Big Bang Did Life First Emerge?
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Graduate Decoding Hubble Data: Acceleration and Age of the Universe
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Undergrad Time Since Big Bang: One Moment Everywhere?
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Undergrad Trying to reproduce curves with angle of CMB anisotropies
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Undergrad Hawking points discovered in CMB
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High School Demystifying the Hubble Constant
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High School Is Our Universe a Causal Patch Stretched by Inflation?
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Undergrad Hawking Radiation and the Negative Energy Particle
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High School Is Earths' potential of 0 volts valid throught the Universe?
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Graduate CMBR anisotropy and cosmic abundances
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Undergrad Troubles understanding slow-roll conditions in Inflation
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Undergrad Dark matter "halo" is a "flattened disk" ?
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High School Our universe's entropy/size vs Bekenstein's theory
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High School Is There a Model That Includes Infinite Space and Finite Matter in Our Universe?
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High School Was the Big Bang simply "Distant Traffic"?
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High School Is our 3D universe a shadow of a 4D Universe?
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High School A Singularity in Semi-Classical physics too?
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High School How do we know that the universe is still expanding
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Graduate What is primordial non gaussianity?
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Undergrad Is Dark Matter Really Necessary in Our Understanding of the Universe?
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High School Are Antiparticles the Key to Understanding the Universe?
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Undergrad Big Bang Singularity vs Black Hole Singularities
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Graduate Energy conservation on Cosmological scales
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Undergrad Could the original size of the Universe be the Planck length
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Graduate How Does a Decreasing Higgs Field Influence the Evolution of the Universe?
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High School Gravitational waves and refraction patterns....
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High School What Causes the Phenomenon of Cosmic Inflation?
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Graduate Zero-Energy Universe: Stephen Hawking Explains
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Undergrad False vacuum and matter density
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Undergrad Understanding the Ly-α Forest for EnSlavingBlair
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Is there a reason the Big Bang would be secret?
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Graduate Is the Universe a Self-Similar Tesselation?
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Graduate What are the frontiers of cosmology research?
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Undergrad Inflation and density perturbations
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High School Hubble’s Constant Changes Over Time
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Black hole vs mathematical singularity
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High School How large was the Universe at its moment of creation?
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Undergrad Entropy and contracting universe
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Undergrad Can Boltzmann Brains Form in an Infinite Universe?
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Undergrad If the Universe’s Mass was 100 At the Moment of the Big Bang....
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