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 Space Time fabric graphic is misleading
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Undergrad Expansion of 3-D positively curved space
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Undergrad Is there a mechanism for creation of negative energy density
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Undergrad What is the energy density of spacetime?
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High School Question regarding if curvature is not constant
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Undergrad Legendre polynomials in boosted temperature approximation
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High School Positive curvature of a 2D surface
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High School Dark matter research paper question
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Undergrad Are there issues with Conformal Gravity as a DM solution?
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Undergrad Total number density of galaxies and problematic expression
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Undergrad Infer the distance of a closest neighbor galaxy from correlation
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High School Was the initial condition extremely cold?
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Undergrad Matter density in Weinberg's Cosmology book
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Undergrad Is the inflationary universe a scientific theory?
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High School Dark matter is "normal" matter in black holes?
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Undergrad Is the increment of the expanding universe part of cosmology
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Undergrad What happens to a star's heat when it gets torn apart by a black hole?
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Graduate Model of the Universe/Multiverse
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High School Discuss Dark Matter & Light: Photons Affecting Space-Time?
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Undergrad Definition of 'dynamical equilibrium'?
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Undergrad What was there before everything came to existence?
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Undergrad How many galaxies do we have red shift data for?
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Undergrad Interpreting the Behavior of Galaxies in an Expanding Universe
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High School HSC dark matter survey...where is it?
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High School Is the energy of empty space concentrated differently in curved spacetime?
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High School The Red Light Shift and Space Debris
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Undergrad What is the acceleration of the universe?
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High School How Does Time Dilation Vary Across the Galaxy?
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High School Expansion or Attraction: What's Driving Our Universe?
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Undergrad How do we know age of the universe?
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Graduate How are parameters in inflation models tuned to align with CMB constraints?
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Graduate How much does peculiar velocity affect distance measurement?
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High School What is the reasoning behind MOND's modification of gravity?
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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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Graduate 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 Why limited discussion of only looking at history
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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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