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 Clarification about the size of the Universe
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Undergrad Deviations of conservation laws in cosmological evolution?
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High School Clarification on how old the Universe is
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Undergrad How many apparent horizons could the Universe have?
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Undergrad Sachs-Wolfe effect in a Dark Energy universe?
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High School Light element abundances for He3/H?
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Undergrad Can there be some kind of photon emission caused by space expansion?
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High School Can physical constants be different in other galaxies?
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High School Gravitomagnetic explanation of Dark Matter
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Undergrad Data Showing Dark Matter Is Not Cold Neutrinos?
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Undergrad Cosmic Event Horizon – Does it have any real effects?
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Undergrad Particle production in an expanding universe?
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Undergrad Is energy conserved during the formation of local systems?
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High School Gas planets with solid satellites
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High School Expansion of Space Itself, rather than due to an Explosion like the Big Bang?
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High School What is the recession speed today of the matter which created the CMBR?
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Undergrad Cosmic Flatness Deduced from CMB
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Undergrad Relationship between geometry and expansion rate
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High School Bound Systems in an Expanding Universe: How Can Galaxies Merge?
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Undergrad LightCone Calculator Improvements
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Graduate Cosmic Tidal Force: Measuring CTF With Strain Gauge
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Graduate Multiverse and observational evidence?
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Undergrad Mining the Universe's expansion?
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On the origin and the evolution of information in the Universe
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Undergrad Receding movement of a stopped object in an accelerating universe?
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Undergrad Lectures on the Varying fine structure constant
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Undergrad Cosmic strings increasing internal energy?
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Graduate Is the FLRW Metric a Valid Approximation for Our Universe on Large Scales?
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Graduate Non-minimally coupled inflation — expansion
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High School Understanding the Expansion of Space: Galaxies Moving Away and Proving Expansion
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Undergrad How Does Space Expansion Affect the Velocity of Galaxies?
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Undergrad Distant Galaxy study, dark matter and the CMBR
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Undergrad What Equation Determines the Cosmic Event Horizon Distance?
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High School Could the source of dark energy be our parent black hole feeding?
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Undergrad What is the significance of slow-roll inflation in cosmology?
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Undergrad JWST breaks another Redshift record
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High School Could a Galaxy Older than 13.8 Billion Years Redefine Cosmology?
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Is the Universe Finite, or Is It Infinite?
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Undergrad Is the Bullet Cluster Evidence for or Against Dark Matter?
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Undergrad A glitch in Jorrie’s Cosmo-Calculator?
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Undergrad Paradox: How can we look back at the Big Bang?
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Undergrad Question re flat infinite universe with a preferred direction
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Undergrad Why is the observed local region of space flat?
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Undergrad A new solution to Olbers' Paradox?
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High School Temporal differences across a galaxy?
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Undergrad Reheating and the horizon problem - chicken and egg?
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Can the Universe's Expansion Allow Us to Escape Its Event Horizon?
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High School Big Bang Question -- How was the first matter formed?
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How are time and distance measured in cosmology?
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What is the total mass-energy of the universe?
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Undergrad The curvature of space and curvature of spacetime
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Undergrad Bubble universes and physical constants
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Undergrad Some questions about Cosmic Microwave Background radiation
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Undergrad I have an error in integrating to calculate the age of the Universe
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Undergrad How does the symbol Λ cosmological constant relate to Ω_Λ or ρ_Λ?
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Undergrad Some questions about Cosmic Inflation
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Undergrad Are there types of spacetime where no symmetries are valid?
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Undergrad Seeking understanding regarding Ω_b, Ω_c, and Ω_m
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High School How much energy does our Universe have?
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Undergrad Postulating a minimum gravitational field strength
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Undergrad Questions about Negative Pressure and Vacuum Energy
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Undergrad If the Universe had a different size, would physics change?
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Undergrad Is the CPT-Symmetric Universe Theory the Key to Solving the Antimatter Mystery?
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Undergrad Alexander Vilenkin and energy of a closed universe
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Undergrad Seeking reference for math related to the age of Recombination
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High School Explaining Cosmic Inflation using analogies
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Graduate Understanding distances in Cosmology
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Undergrad Will the upcoming experiment PICO measure kSZ temperature anisotropy?
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Undergrad Looking for a chart showing various growths of the Universe
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Graduate Peebles Equation for fractional electron density
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Undergrad What's the source of energy for the universe's expasion?
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High School How good are our ears? (Detectable Interstellar signals)
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Graduate Can Representing Ideas be Possible?
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Undergrad Observations fit poorly with the Standard Model of Cosmology
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Undergrad How is the sound horizon at recombination and BAO measured in the CMB?
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Undergrad How far into the Universe can we theoretically reach?
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Undergrad Is Entropy in the Universe Lower Now Than After the Big Bang Due to Heat?
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Undergrad Varying laws of high energy physics in inflation?
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Undergrad An odd result from integrating to calculate the age of the Universe
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Undergrad Information lost at the Big Crunch?
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Undergrad Questions about bayronic acoustic oscillations
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Graduate Questions: Gott-Li Can a Universe Create Itself?
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High School What is the oldest of each class of star?
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High School Experimental evidence on cosmological redshift
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Graduate Which galaxies have the best studied evidence for dark matter?
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Graduate Graceful exit of a cosmological inflation model
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Undergrad What does the equation dΩ32 = dr2 + r2dΩ22 mean in terms of flat space?
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High School What Function Does Dark Matter or Energy Serve?
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High School For object 3.26 million light-years away, light redshifted by 70 km/s
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Graduate Numerically solving Scalar field coupled to Friedman equation
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High School How could something that is infinite (the Universe) expand?
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High School What does the Universe exapand into?
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Undergrad Calculating the probability that the Universe is finite
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Undergrad What if the Universe expands faster than the speed of light?
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High School Basic confusion about the Big Bang and light cones
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Undergrad Question about the Hubble Constant
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High School Question regarding light from distant objects
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Undergrad An idea for calculating the probability that the Universe is flat
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Undergrad Edwin Hubble and the Evidence for Universe Expansion
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Graduate What assumptions underlie the proof that singularities are inevitable?
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