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 Predicted sizes of (observable) universe
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High School What are the most likely ways of finding Dark Matter?
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Graduate Space time expnasion, age of universe.
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High School Is 200my enough for galaxies to form
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Undergrad Does Dark Energy drive up Entropy?
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High School The Center of the Milky Way Galaxy?
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High School How Did the Universe Create Itself from Nothing?
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High School Was there ever a state of nothingness?
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High School What Happens When a Black Hole Interacts with Antimatter?
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High School Is Time's Flow Affected by Cosmic and Quantum Scales?
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Undergrad Do we need Dark Matter or are we just time blind
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Undergrad Understanding Hubble's Graph: Velocity and Time Relationship Explained
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High School Why is vacuum energy assumed to be uniform?
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Undergrad Object moving out of the Observable Universe due to Expansion
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Undergrad Exact expression for the tensor-to-scalar ratio
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High School What can we see from the farthest reaches of the universe?
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Graduate Does the Hadronic Era Alter the Equation of State?
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High School Black holes are creating galaxies with their gravitational force
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High School What would a timeline for the Big Rip look like?
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High School What is the appropriate time/matter model for the universe?
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Undergrad Can a finite universe end in heat death?
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Undergrad Problems with the theory of inflation
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Undergrad How Does Gravity and Density Influence the Flow of Time?
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High School The known universe is expanding?
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Undergrad Are Galaxies Moving or is Space-Time Expanding?
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Undergrad Big Bang nucleosynthesis Wiki Equation for t x T^2
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Undergrad Question about expansion and photon fatigue
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High School Is Time Expanding Along with Space in the Expanding Universe?
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High School Why does expansion redshift light if....
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High School Is the center of the universe empty?
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Undergrad How Would Future Species Understand a Dynamic Universe?
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Graduate Question about the age of the universe
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High School The distribution of normal matter precisely determines gravity
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High School Does the Frequency of Gravitational Radiation Alter the Cosmological Constant?
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High School Book recommendations for Big Bang Model?
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High School Why do we assume the existence of time (flow)?
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Undergrad What Is the Cosmic Horizon and Its Relation to Black Holes?
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Undergrad Are we living in a Boltzmann box ?
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Undergrad A possible solution to the cosmic lithium problem
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High School Is Everything outside the local group moving away from us?
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Graduate Detection of 6th Force of Nature: Zhang & Feng Claims
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Undergrad Variations in the local value of Hubble constant
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Undergrad How is the value of tT^2 calculated for neucleosynthesis
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Undergrad What is the link between dark matter and antimatter in the universe?
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High School Animation to explain the balance of celestial bodies of the universe
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High School Perhaps a silly analogy - hologram light source retreating?
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Undergrad At which time did the CMB become dark?
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High School How can we see 45B ly away if the universe is only 13B years
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High School White Hole as an explanation for the big bang and inflation
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Undergrad Is there a drag on Earth caused by its motion relative to the CMB rest frame?
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Undergrad Great attractor and the CMB dipole
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Undergrad Matter term in Friedmann’s equation
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Undergrad Is the Universe's Contraction Model Too Fine-Tuned to Be Plausible?
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Undergrad When Does the Radiation Epoch Begin with a Scale Factor of ~t1/2?
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Undergrad Time & Cosmology: Observing Past Quantities & Effects on Equations
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High School Background Radiation: Is It From Beyond Our Galaxy?
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Question About Moving Observers and Observable Universes
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Undergrad Friedmann Equation Analysis, expansion of the universe?
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Undergrad How is entropy defined for cosmological phenomena?
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High School Is expansion the same Throughout the Universe
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Undergrad Evolution of the Energy Density Parameters
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Undergrad Discover the Latest Cosmological Parameters for the CDM Lambda Concordance Model
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Undergrad Chaotic Inflation: Does it Involve Phase Transition?
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Undergrad Integrating the Friedmann Equations
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High School Is The Holographic Universe Theory Gaining Popularity And Why?
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Undergrad Is momentum conserved in the entire observable universe?
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Undergrad Einstein & Lambda: 1917 Static Model Review
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Energy scale of Hubble constant for dark energy scalar field
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High School Calculating Distance: What Am I Doing Wrong?
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Undergrad Electroweak symmetry breaking and quantum tunneling.
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High School Does the 2LOT rule out an eternal universe?
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High School Mass and free fall speed under gravity
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Undergrad Inflation and Gaussian CBR pertubations
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Graduate Q: Black hole event horizon vs distortion effects
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Undergrad Different forms of energy density in inflation
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Undergrad Rescaling the equation of motion of inflation
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High School Redshift of distant galaxies....
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Undergrad Are Finite Universe Models Plausible Despite Flat Curvature?
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Undergrad How Does the Lyman Break Drop-Out Technique Identify High Redshift Galaxies?
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Undergrad Estimate the number of CMB photons in 0.25-litre
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Undergrad How Can Gravitational Lensing Help Detect Dark Energy?
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Undergrad Where did the Dark Energy (or similar mechanism) come from?
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Undergrad Question about "the big bang happened everywhere at once"
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High School Evolving Dark Energy: A Missed Revolution?
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Undergrad Qs re dark matter when all baryonic matter is in black holes
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Undergrad Unraveling the Mystery of Dark Matter: The Missing 96% of the Universe
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Undergrad How Can I Graph Hubble Term vs. Inflaton Using Mathematica?
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High School Dark matter can be cold warm or hot
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Undergrad Qs: What is known and known to be unknown about DM
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Graduate Starobinsky Inflation and Supergravity
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Effort to get us all on the same page (balloon analogy)
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High School Is dark matter self-interacting?
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Undergrad What is the Role of Space in this Apparatus?
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Undergrad Boltzmann Brains: Existence, Models & Opinion
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Undergrad Cosmological electroweak phase transition
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Undergrad Dumb Question: How do we know galaxies are in SSCM?
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Has anything in the universe ever reached 0 Kelvin?
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Undergrad Is the fabric of space a "medium" for light?
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Undergrad How to solve for the volume of the universe / redshift
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High School Emergent Gravity and the Dark Universe
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