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 Accelerated Hubble expansion -- Is the second derivative positive?
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Undergrad Effect of Dark Matter on fast moving bodies
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High School Question about the size of atoms as time progressed
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High School Why does our Universe have more electrons than positrons?
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High School Dark matter does not interact with ordinary matter....
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Binnig's fractal evolution applied to multiple universes?
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Undergrad Laws Before Big Bang or After Big Bang
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High School The accelerated expansion of the universe; redshift and time/distance
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Undergrad What Key Issues Should Cosmologists Address in the ΛCDM Model?
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Undergrad Why can you not describe massive neutrinos with a temperature?
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Undergrad How do we observe the CMB at all?
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High School A Meritable Veritable Time Paradox?
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Undergrad What proof do we have that the universe is homogenous?
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High School Low entropy early Universe and the heat death musings
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Graduate Can Cosmic Strings Trigger Vacuum Decay?
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Undergrad How Does The Cosmic Microwave Background Show That The Universe is Expanding?
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Undergrad Is Negative Dark Energy Density a Valid Concept in Universe Models?
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Graduate Exploring Minkowski: A Multi-Dimensional Grid for Studying Other Spaces?
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Undergrad Meaning of the inertial energy density
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Graduate The Cosmological Principle means infinite Observable Universes
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Undergrad CMB creation, distance measurement question
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High School How was the amount of matter in the Universe determined?
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High School Did energy begin to exist? Can energy exist without space and time?
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Undergrad Is the backward extrapolation of the expansion of the Universe valid?
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Undergrad How to measure a 21 cm EM wave if it is Doppler shifted?
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Undergrad Wheeler's Mutability principle and multiple universes?
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Undergrad If a 4th dimension existed would universe expand anisotropically?
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Undergrad Discover the Rare Black Neutron Star
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High School Does the Universe really have to be at least as old as the oldest thing in it?
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Graduate Lovelock Theorem & FRW Domain Wall Cosmological Model in f(G) Theory
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Undergrad Hypothetical Eclipse Calculation
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High School Quantum total eclipse of the sun?
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Undergrad Big bounce theory in light of the closed Universe finding
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Undergrad How Do You Derive Transverse Comoving Distance?
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Undergrad BICEP2's Mis-Estimation: Was Not CIB Subtraction the Cause?
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High School What is Consciousness? How does it affect our Physical Universe?
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Undergrad Mass & Radiation 3D Distribution in the Universe
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Undergrad If the Universe is closed, is it thereby self-contained as well?
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Undergrad Is the Universe bigger than we think?
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Graduate N-body simulation with varying neutrino mass
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High School Half of the Universe’s ordinary matter may have been found
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High School Lensing Gravitational Waves Like Light?
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Undergrad Conservation of energy in cosmology
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Graduate How to see if a cosmological model is flat?
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High School Is the Universe Truly Finite According to the Big Bang Theory?
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High School How does emergent spacetime work?
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Undergrad The picture of the Comoving coordinate
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Undergrad Curvature of Space in the Context of Cosmology
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Undergrad What happens when a Neutron Star forms a Black Hole?
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Undergrad Constant Curvature and about its meaning
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Undergrad The Cosmological Principle and the Universe
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Undergrad Possible illogicalness of a 3-sphere shape of the Universe's space?
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What percent of the universe is outside of galaxies?
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Undergrad Can the multiverse hypothesis be an explanation for life on Earth?
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High School If the Multiverse is correct why don't they appear inside our own?
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High School What Happens When You Fall Into a Black Hole According to Stephen Hawking?
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Undergrad Gauge transformation in cosmological perturbation
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Insights Dark Energy Part 3: Fitting the SCP Union 2.1 Supernova Data
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Insights Dark Energy Part 1: Einstein-deSitter Cosmology
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Insights Dark Energy Part 2: LCDM Cosmology
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Undergrad Big Bang singularity: can we say anything about its size?
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High School If the Universe keeps expanding this way, it gets torn apart
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Undergrad Has the evidence for anisotropy of cosmic acceleration been discussed?
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High School Meaning of Time / Space axes swapping (for Time)
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High School Black hole movement with no time......?
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Undergrad Who was the first to find an initial singularity in GR models of the universe?
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Insights The Evolution of the Universe, Cosmic Web and Connections
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Undergrad Can Dark Matter Exist in Higher Dimensions?
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Undergrad What Does a Negative Value for the Deceleration Parameter Imply in Cosmology?
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High School Is it possible to see the history of space if it expands faster than light?
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Undergrad Understanding inflationary cosmology
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Undergrad Is My Basic Understanding of Universe Expansion Correct?
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Undergrad Understanding the property of the Comoving Coordinate
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Undergrad Comoving Reference Frame in Cosmology
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Graduate New MOND Simulation: First Galaxy Formation Model in Milgromian Gravity
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Undergrad Is the Brans-Dicke Vacuum Cosmology Theory Still Relevant?
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High School What Does it Mean When We Say the Universe is 'Flat'?
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Undergrad Coordinate dependence of recession velocities
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High School Possibility of Another Big Bang?
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Undergrad How Can the Newtonian Spherical Ball Be in Stable Equilibrium?
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Undergrad Is Big G and Dark Energy Constant Over Time?
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Undergrad How do physicists know that an external world exists?
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Inflation and measurement of cosmic bodies
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Undergrad In the beginning there was.... a black hole?
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High School Why are there 4 dots in Einstein rings?
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High School Dark matter that doesn't gravitate?
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High School How Does Modern Particle Accelerator Energy Density Compare to the Big Bang?
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High School I don't understand the evidence or possibility of the Big Bang
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Undergrad Is There really a Hubble Tension?
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Undergrad Understanding the Age of the Universe
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Undergrad Finite density at the BB preinflation epoch implies a finite universe?
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Undergrad Is the Pressure Inside a Black Hole So Intense That Atoms Cannot Hold Form?
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High School Other lines of evidence for Dark Energy? (Besides supernova data)
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Graduate Can there be a lawless universe (according to Hawking)?
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Undergrad Cosmology in Crisis Podcast by LSST Scientists
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Undergrad DDO 68: A Young Galaxy Supporting the Steady State Theory
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Undergrad Does the expanding Universe follow Lorentz contraction?
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Undergrad Dark Energy as repulsive gravity
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High School Could Earth's Atmosphere Survive a Close Gamma Ray Burst?
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High School Why The Big Bang banged and didn’t collapsed into a black hole?
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