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 What are the alternative theories for the end of the expanding universe?
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Undergrad Life permitting ranges for fine tuning constants
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High School Can Primordial Black Holes explain Galaxy formations
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Graduate What Is a 'Black Hole' & What Does It Mean for Particles?
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Undergrad What is the lower bound constraint for G in terms of anthropic principles?
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Undergrad What happens to the information entering a Black hole?
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High School Does the expansion of space influence the passage of time across the universe?
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Graduate Calculating the power spectra of scalar perturbation
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High School Does the geometry of space really change with gravity?
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Undergrad Interesting controversy about inflation models of the universe
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Undergrad Centre of mass of the observable universe
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Undergrad Comoving mass density leads to linear cosmology?
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Graduate Variation of Hubble constant in cosmological time
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High School Definition of unshifted spectral lines?
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Undergrad Is the Force on a Particle in a Homogeneous Static Universe Always Zero?
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Undergrad Alexander Vilenkin spontaneous creation
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High School Evidence for interacting dark energy from BOSS
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Undergrad How Does the Hubble Parameter Relate to Galaxy Movement?
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Graduate Hubble scale and energy density during inflation
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Undergrad Entropy and Expansion in a Simple Universe
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Undergrad What is the purpose of cosmological simulations in understanding dark matter?
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Undergrad How Can Data Constrain the Number of e-Folds During Inflation?
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Undergrad Does a black hole cut the fabric of spacetime as it changes
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High School Why Can't We Find the Centre of the Expanding Universe?
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High School Is Dark Matter physics low or high energy physics?
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High School Is Space an Object Capable of Bending?
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Undergrad How will the universe empty out?
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Undergrad Entropy Change in Time of Universe
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High School What is the origin of the Gibbons-Hawking temperature?
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Graduate Is Dark Energy an Illusion? A Closer Look at Concordance Cosmology
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Undergrad Does the number of causal patches increase bc of expansion
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Undergrad Consequence of curvature of spacetime
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Undergrad Do particles create space over time? Is that expansion?
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Undergrad Argument that a maximum density Universe expands linearly
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High School What is meant by the size of the early observable universe?
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Undergrad Where Would Ancient Intelligent Life Have Seen Cosmic Background Radiation?
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High School Lawrence Krauss and shortening the lifespan of the universe
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High School Could Boltzmann Brains Become a Reality in the Far Future?
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High School How Does Space Expand? Understanding Universe Expansion
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Undergrad Plateau models of inflation after Planck
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Undergrad Oldest galaxy to date: UDFy-38135539
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Will the Universe one day become smaller?
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Graduate A cosmological expansion problem too difficult for me
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High School Is the Expansion of the Universe Uniform?
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Undergrad CERN n_TOF experiment: 'Age of the Universe'
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Undergrad Observing Naked Singularities: Implications for Quantum Gravity
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High School Do we still live in a Big Bang Singularity?
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Undergrad Is it possible to travel between the multiverses?
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Undergrad Using big data to identify astronomocal data bias
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High School Why doesn't dark matter reside in gas clouds?
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Undergrad Why Can We Still Observe the Cosmic Microwave Background?
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Undergrad Curvature and the size of the Universe
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Undergrad Is there a relationship between dark matter and anti-matter?
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Undergrad Math doesn't add up: stars + planets < particles in universe?
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Understanding Expansion of Space
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High School Will eLISA have the potential to detect early universe GWs?
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Undergrad Energy-momentum tensor and Friedmann Equations
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High School Naive Calculation of the Age of the Universe
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Undergrad Big Bang timing: according to what frame of reference?
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High School How can we see Background radiation
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High School Is the Universe Truly Eternal or Just a Temporary Fluctuation?
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High School Does every elementary particle eventually decay into quarks?
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Undergrad New Wired article on "where's the antimatter"
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High School Finite Universe vs. Uncertainty Principle
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High School Just how Powerful is Computer Science + Astrophysics?
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High School Space expanding or Time speeding up? Part 2
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Graduate End of Inflation: Definition, Meaning & Models
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High School Conservation of Energy and Expansion Redshift
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Undergrad Inflation, horizon-problem and thermal equilibrium
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High School Is it possible to compress the space without gravity?
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Undergrad How to embed the universe in R^4
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High School Edge of the Universe: Is It Real?
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Undergrad Spacetime Relativity: Universe Expansion & Our Place in It
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Undergrad Carolo Rovelli on infinity in LQC
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Undergrad Dragging a wormhole into a black hole
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High School Information paradox in black holes
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Undergrad Probability of not entering de Sitter
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High School Is the Earth Really 4.5 Billion Years Old or Much Older?
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Undergrad Size and shape of a black hole singularity?
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High School Are Black Holes linked to our Universe & Dark Energy/Matter?
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High School Simplistic question about mass and gravity
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High School Is Dark Matter in the 100GeV range
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Graduate What Does Prof Krauss Mean About False Vacuum Decay and Cosmology?
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Graduate Angular power spectrum, bias from N weighted events
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Undergrad Determining H value from scalefactor
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Undergrad Expanding universe and the Boltzmann brain problem
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Why is it that Mercury rotates at a faster rate than say Pluto
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High School Units for Entropy of Simple Black Holes
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Undergrad Gravitational waves as means for communication
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High School Cause of Inflation: Link to Dark Energy & Quintessence?
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High School A question about an interesting article on dark matter
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Graduate Observational evidence for accelerating universe
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Undergrad Shape of the universe -- Does it change with time?
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Undergrad Do Event Horizons always contain a singularity?
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Undergrad How do we measure energy density of radiation?
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Undergrad What Evidence Exists for the Universe Before the Cosmic Microwave Background?
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High School A Long Time Ago in a Galaxy Far....
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High School Where Was Dark Energy Before the Accelerated Expansion Began?
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High School Exactly how quantum tunneling leads to a Big Bang?
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Undergrad Q re early universe matter-antimatter annihilation
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