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 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 Fine Tuning Constants: Understanding Variables and Ratios | Physics NIST
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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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Undergrad 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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Undergrad Big Freeze and Law of convervation of energy
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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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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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