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 Cosmological expansion and uncertainty
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Graduate WIMPs or MACHOs: Which Dark Matter Candidate Holds More Promise?
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Graduate Does rest mass increase in conformal co-ordinates?
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Undergrad Einstein equivalence principle
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Graduate How Does General Relativity Predict an Expanding Universe
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Graduate Did the universe really have zero extent at the beginning?
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Graduate Time dependence of the Ratio Hubble length to scale factor
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High School A circle in the Hubble Ultra Deep Field picture?
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Graduate Definition of Energy in Friedmann equations?
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Graduate Multiple big bangs in one continuum - Question
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Graduate Visibility of Matter in the Universe
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Graduate Moon Landing Q&A: Solar Winds & Astronauts
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Graduate Total mass and/or future of dark energy = cyclic universe?
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Graduate Could Zipf's Law and Dark Matter be linked in the cosmos?
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Graduate Gravity, Dark Matter and Dark Energy are all one
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Graduate Cosmology's sole "rate of expansion" is declining
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Graduate How can quantum tunneling create Big Bang after heat death?
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Graduate Why is the non-zero value of spatial curvature +/- 1?
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Graduate Is the metric basis for space expanding as the universe expands?
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Undergrad Creating something from 'nothing' in our Universe
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Undergrad Zero energy universe means nothing exists at all times
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Undergrad The Universe's Sum: Is Zero Theory Plausible?
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Graduate Trying to understand Dark Energy
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Graduate Alternative hypotheses regarding dark energy?
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Graduate Cold Spot in CMB: Real or Systemic Error?
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Graduate How have N Body simulations solved the missing satellite problem in ΛCDM?
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High School Where is Tau Ceti Located in the Night Sky?
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Graduate Could an Electron-Proton Pair Form an Atom in an Alternative Universe?
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Graduate Does a finite universe require 4 spatial dimensions?
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Graduate Are modified gravity models viable
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Graduate What does the big bang theory really tells us?
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Graduate Is the Universe's Expansion Truly Slowing Down?
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Graduate What proportion of stars have proper motion
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Graduate Are the Friedmann Equations Applicable to the Pre-Inflationary Epoch?
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Graduate Superfluid Dark Matter: A Review of Theory & Evidence
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Graduate Is the True Vacuum in de Sitter Space Characterized by Minimum Mass?
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Graduate Has neutrino redshift been observed?
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Undergrad Can Quantum Time and Space Have Countable States After the Big Bang?
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Graduate Does a rigid box of gas cool over cosmological timescales?
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Graduate When Did We Last Get a Glimpse of the Big Bang?
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High School Can Black Holes Really Die and What Are Their Secrets?
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Graduate Origins of the Fundamental Interactions/Forces
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Undergrad Infinite Universe: Can It Ever End?
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Graduate How can light have momentum if it has zero mass?
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Graduate Is Multiverse proven by Plank data?
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Graduate Metric expansion misunderstanding
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Graduate MOND and the missing baryons problem
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Graduate No Dark Matter or gravity modification for flat rot
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Graduate Gravitational lensing as a way of observing Milky Way?
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Graduate The Inflaton Field And Repulsive Gravity
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Graduate Expansion then Contraction....an infinite Elastic Collision?
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Graduate Time, Mass & Space: Does Time Stay Consistent?
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Graduate Is the universe fine tuned for life
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High School Suggest a Quantum Physics Book for a 16 Year Old
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Undergrad Cosmology looks beyond the standard model
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Undergrad Calculating Universe Density: Cosmology Equations
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Graduate The Universe Never Expands Faster than the Speed of Light
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Undergrad At what speed is our universe expanding?
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Undergrad Does an Expanding Universe Alter How Quickly Light Travels Through Space?
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Graduate Will a bouncing cosmology lose information
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Graduate Why Does Increased Baryon Loading Shift Power Spectrum to Higher Multipoles?
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Graduate Alternative Theories: Ghirardi-Rimini-Weber and the Many Worlds Interpretation
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Graduate Why should the Bullet Cluster focus light?
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Graduate First detection of direct collapse black holes?
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Graduate Solving Freidmann Equation: Understand Calculations & Cosmology
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Graduate What can the Anthropic Principal predict?
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Graduate Event Horizons = Cosmological Horizons?
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Undergrad Why are photons affected by gravity?
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Undergrad About doubling the mass of the planets and the sun of our solar system
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Graduate Gas Mass Calcuation in Galaxy Cluster
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Graduate Are Interstellar Extinction Variations Misleading Cosmological Measurements?
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Graduate Time at the big bang and in very early time after that
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Graduate Is the X-Ray Mass of the Coma Cluster Accurately Measured?
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Graduate Random Walk Question re Inflation
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Graduate Does the Bullet Cluster Disprove MOND and Challenge ΛCDM?
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Graduate Origin of Quantum Perturbations?
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Graduate Good 1st year grad level texts in galaxies and cosmology
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Graduate How Does the CMB Frame Differ from Other Frames in Relativity?
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Graduate How many hypothetical particles do we need
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Graduate Fine tuning, muitverse and a double standard
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Graduate What is the evidence for dark matter in the solar neighborhood?
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Graduate Do Galaxy Clusters follow De Vaucouleurs' Law?
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Graduate Distinction between special and general relativity
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Graduate Re Dark Matter and the Horizon Problem
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Graduate What Causes the Higher Peaks and Damping Tail in the CMB Power Spectrum?
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Graduate Is the location of galaxy X in the universe constant?
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Graduate Negative energy is repulsive, but PE is negative, so?
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Graduate How to measure CMB anisotropies *In Practice*
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Graduate Pre-Big Bang Environment & Rules: Insights on the Known Laws of the Universe
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Graduate Does Gravity Gravitating Alter Cosmology?
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Graduate Frame of reference: grade 2n vs. grade 2n-1
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Graduate Does space have a velocity in spacetime?
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Graduate How do you project a Sersic Profile into 3D?
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Graduate Accurate measurement of z = 8.68 galaxy
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Graduate Can We Measure the Probability of Order in the Universe?
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Graduate How/Why does GR break down in Planck Epoch?
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Undergrad Size of the Universe: Imperial & Metric Measurements
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Graduate Size of Universe: Planck Time to Inflation
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Graduate Questions re electroweak de-unification during inflation
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Graduate Understanding Big Bang Singularity: Physics Forums Q&A
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