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 The speed of light and Hubble Flow
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High School Gravitational Waves & Dark Matter: Is There a Connection?
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Undergrad Physics & Objects Beyond Space & Time: Big Bang Singularity & Black Holes
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Undergrad Causally separated regions in CMB?
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High School Acoustic Waves & Their Impact on Inflation: What You Need to Know
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Undergrad Why is an improbable early universe unacceptable?
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High School Calculating Time to Reach 100,000 Trillion Meters in Hubble Flow | PF Forum
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Undergrad Unraveling the Mystery: The Composition of Quasars
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Undergrad Universe is a sphere that is centered on any observer? How?
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Graduate How to convert between different mass measurements for CDM H
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Undergrad What Insights on Time in Physics and Cosmology Emerged from the Pi Conference?
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Undergrad Infinite Universe from Dimensionless SIngularity
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High School Is the Age of the Universe a Coincidence?
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Undergrad Could Dark Energy Be an Illusion of Spacetime Geometry?
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High School Who was the observer for the first 10 billion years?
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High School From a 4D perspective would 3D infinity exist?
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High School What is a quantum fluctuation....
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High School Understanding the Lagrange Points: What's Going Wrong with L2 and L3?
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High School How are neutrinos distributed in the universe?
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High School Are massive gravitons what ripple when galaxies collide?
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Undergrad Age of the Universe as Measured by a Non-Co-Moving Observer
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High School How can dark matter exist in a vacuum?
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High School How is the Age of the Universe Determined?
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High School Why is the age of the Universe finite?
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Undergrad Are Galaxies Moving Faster Than Light Due to Space Expansion?
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Undergrad What does "expansion of the universe" mean?
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Undergrad Time translation symmetry and the Big Bang
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Graduate Transition from opaque universe to release of CMB
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Undergrad Are Exotic Leptons Crucial for Life's Existence?
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High School What Causes the 2.7 Kelvin Temperature in the Vacuum of Space?
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High School Is dark matter a sea of massive photons?
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High School Is the Variable Speed of Light Theory a Viable Alternative to Inflation?
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Undergrad Detecting Entanglement in the Inflationary Potential: Is it Possible?
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High School The universe is crowded with black holes
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Insights Where Did the Big Bang Happen? - Comments
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High School Could the universe's Big Bang be 1D?
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High School Could LIGO Have Detected Dark Matter?
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Undergrad The Infinity of Days in the Eternity Universe
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Undergrad Is the total amount of gravity in the Universe conserved?
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Undergrad What are the Different Types of Multiverse Theories in Cosmology?
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High School Sgr A Relativistic Jets Visible?
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Undergrad Dark Energy - something from nothing?
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Undergrad Quantum Kinetic Energy of Neutrons, Protons and Electrons
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High School Hubble's Law: Explaining Why Distant Bodies Recede Faster
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High School Density of Black Holes: Unveiling the Universe's Secrets
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Undergrad Remote observer sees black hole evaporate
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Graduate Systematic study comparing cosmological models?
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Undergrad How can the universe expand faster than light?
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High School Is the universe expanding faster than expected
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Undergrad Different densities of the universe on different angles?
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High School Is Space Truly Expanding or Just a Pedagogical Tool?
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High School Infinite multiverse would contain the ridiculous?
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Undergrad Rate of Supernovae in the Milky Way Galaxy: Scientists' Best Estimate
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High School Is the concept of true distance compatible with relativity?
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High School What is the reason for galaxies fading in the distant future?
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High School What Is the Nature of Space and Its Infinite Possibilities?
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High School Universe is accelerating expanding
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High School Could Dark Matter be Time itself?
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High School How do we know we are not inside a blackhole?
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High School Data on time for fading of galaxy?
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Graduate The equation of state of non-relativistic energy
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High School Dipole pattern for Fine Structure Constant?
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Life forms that live in decreasing entropy phase of universe
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High School Predicting the future of a deterministic universe
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Graduate What is the significance of peculiar motion in galactic rotation data analysis?
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High School Expansion of space and momentums of galaxies
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Theories and questions on the expansion of the universe
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Undergrad Vacuum energy density after inflation
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Undergrad Is the BB Paradox Compatible with an Infinite Expanding Universe?
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High School Will the Universe Eventually Go Dark?
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High School Question about the nature of Gravitation
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Undergrad What is the History of Dark Matter?
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High School Why is the redshift not the result of something else
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Undergrad Is Information Conserved in the Universe?
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Undergrad Is Probability Meaningless in an Infinite Universe?
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High School Super-luminous Sphere Fading: Will Smaller or Larger Spheres Fade Away First?
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Undergrad Physics in a universe with instant communication
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Undergrad Expansion of the universe, a poor choice of words?
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High School Does Time Reverse Inside a Black Hole's Event Horizon?
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Undergrad How Does Dark Matter Density Affect Galactic Rotation?
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Undergrad Horizon Riddle (Infinite Horizon Problem)
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The Big Rip - new evidence for it?
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High School At what point would we stop seeing a star?
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Undergrad Does positive curvature disprove eternal inflation?
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Graduate How do we say that the universe we live is 3 dimensional?
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High School How to apply Einstein's STOR to expansion
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Undergrad Size of Universe: Exploring 13.7bn Years of Space
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Rotational universe without dark energy and dark matter?
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High School Is the Universe a Type of Fluid?
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High School Expanding from and eventually to a singularity?
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Undergrad Plotting number of halos per logarithmic bin
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High School Hubble equation function of time
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Undergrad Spacetime expansion and conservation of energy
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Undergrad Experiment to Determine if Spacetime is Granular
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Undergrad Inflation assumes ##\ddot{a}<0## after inflation?
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Tyson Says It's 'Very Likely' The Universe Is a Simulation
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Undergrad Spatial homogeneity and the functional form of two-point functions
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Undergrad Understanding Wiki's Milky Way Galaxy rotation chart
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Undergrad What differentiates inflationary models from each other?
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High School Is expansion caused by unknown tension in space/time?
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