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.
Graduate Equilibrium point of matter and radiation density
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High School Questions about cosmic background radiation
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High School What is the size of the observable Universe?
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High School Age of the Universe at the recombination?
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High School Age of the Universe vs Age of the Stars
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Undergrad Any direct measure of Universe expansion via galaxy subtended angles?
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Graduate Part of the Hubble discrepancy can be explained by local underdensity
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Graduate Friedmann-Robertson-Walker Models
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Undergrad CMBR & Flatness: Mapping Universe Flatness?
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Is the Hubble Constant Truly Constant?
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Undergrad How Can We Interact with Dark Matter for Sci-Fi Novel?
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Undergrad What do "marginalized" or "marginalized error" mean? (contours - posterior)
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Undergrad Does the Strong Anthropic Principle have any equivalent specific model?
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Undergrad Some redshift from prism effect of a gravitational lens?
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High School Questions regarding expansion, the vacuum in space, and black holes
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High School When could life theoretically exist in any star system after the Big Bang?
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High School Can Hypothetical FTL Technologies Enable Travel to Other Bubble Universes?
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High School What is the important scale of things in the Universe?
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High School Dark Matter & BAO: How Does it Suppress Baryonic Oscillations?
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High School Examples of theoretical proofs overturned by evidence?
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Undergrad Chameleon Theory: Detecting the Particle with Astronomical Surveys
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Undergrad Question about the Cosmological Constant
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Undergrad Formula for the large-scale bias of galaxies
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Undergrad Hubble's law and conservation of energy
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Graduate Forecast with Fisher formalism : loss or gain of information
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Undergrad Amount of energy inside a sphere of radius 1au around the Sun
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High School Particle Deceleration in Relativistic Jets?
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High School How do we know that the Universe is expanding?
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Undergrad What Justifies the Slight Preponderance of Matter Over Anti-Matter?
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Undergrad How is dark matter thought to have formed a network scaffolding?
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Undergrad Does the universe have a definite "size"?
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High School Expansion or contraction -- how do we know which?
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Undergrad Equation of state and density parameter
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Undergrad Cosmological constant and structure formation
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Undergrad Spacetime curvature and curvature index
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Undergrad Creation of our universe from zero energy?
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High School What is the probability that the Universe is absolutely flat?
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Undergrad Coherence length of velocity fields
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Undergrad Dark Matter not present in Galaxy when distance is Increased
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Cosmological models with variable EoS
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High School Is Dark Energy Born at the Big Bang or Continually Created?
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Undergrad Did Universal Physical Constants Exist at the Big Bang?
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Undergrad Can Merging Black Holes Have Infinite Kinetic Energy?
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Undergrad Qs re Cosmological Models Using Bayesian Probability Methods
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High School Is Dark Matter a Misunderstood Global Effect?
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High School Age of Universe: 13.8 Billion Years
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Undergrad Is the Universe a 3-sphere or a 4-sphere?
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Graduate Dark matter and energy explained by negative mass
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Undergrad What Innovative Coding Projects Can Enhance Your Understanding of Cosmology?
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Undergrad Why Does Wormhole Travel Take Longer Than a 'Regular' Path?
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Direct Detection of Cold Dark Matter
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High School Could Matter/Anti-Matter Annihilation Explain Dark Energy and Dark Matter?
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High School Is the Hawking-Hartle Euclidean approach confirmed by CMBR data?
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Undergrad What Future Experiments Could Confirm Extra Dimensions in Cosmology?
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High School Is 3D reality merely an illusion?
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Undergrad How Does Baryonic Matter Alone Affect the Universe’s Structure?
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High School Is the "Information Paradox" close to getting resolved?
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Undergrad What is the refractive index of the Universe?
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Undergrad How does the expansion of the Universe affect black holes?
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Analysis Paralysis: A Must-Read Paper on Cosmology Theory/Data
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Historical reprint/coverage papers requested
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Interesting video on infrared modifications to gravity
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Observational constraints on quarks in neutron stars
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What is the connection between dark matter and ordinary baryonic matter?
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How unitary cosmology solves the inflationary entropy problem
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Explore Holographic Dark Energy: Edmund J. Copeland et al.
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Undergrad Why is this Hubble plot linear for Omega=2 closed universe?
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Undergrad What will eventually happen to all EM waves / photons?
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Undergrad Are MOND Equations Consistent Across Sources?
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Graduate Dark Matter Real: Studies Confirm, Modifying Gravity Can't Work
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Undergrad Was Dark Energy Dominant Over Matter in Early Universe?
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High School The singularities of gravitational collapse and cosmology
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Undergrad Does the newly measured expansion rate change the odds for Big Rip?
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Undergrad Expansion of the Universe question
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High School If the universe were played in reverse, how would it differ?
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Undergrad Universe younger and faster than thought
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Undergrad Will the Big Rip basically be the Big Bang for the next universe?
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Undergrad Is the age of the Universe "boundless"?
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Graduate Different FRW Cosmological Models
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High School What A White Hole Will Look Like?
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Undergrad Provide me the paper by Peebles,P.J.E 1980 and 1993
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High School What does 4 D spacetime look like?
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Undergrad Helium Hydride data, Early universe chemistry evidence?
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Undergrad How can an expanding Universe look homogeneous?
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Graduate Abundance and mass spectrum of PBH
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High School [Curiosity] Are there any central databases of Red Shift?
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Graduate Why the fine-tuning argument for improbable existence is a fallacy
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High School Could accelerating expansion be caused by a "spinning" universe?
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Undergrad Can black hole studies shed any light on dark matter
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Undergrad Is the Divisor (2π)^3 Necessary in Photon Gas Equations?
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Undergrad Dark Plasma charged under unbroken U(1)' gauge interaction
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Insights How to Create a Universe - Instructions for an Apprentice God - Comments
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Undergrad What is the definition of the entropy of the Universe?
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Undergrad What would the universe look like without dark matter?
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Undergrad Does the Friedmann vacuum equation have a linear solution?
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Undergrad Expanding universe needs a big bang?
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Undergrad Why can't LIGO detect collisions of super massive black holes?
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Undergrad Is the Minkowksi/Einstein Block Universe theory science?
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High School 83 quasars right up against the Event Horizon
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Undergrad What would a big crunch look like observationally?
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