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 Flatness Problem: Critical and Actual Density
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Undergrad Gravitational field inside a void
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Undergrad Default 'now' when discussing astronomical things
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High School Question pertaining to dark energy
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Undergrad Where galaxies are now or is there a universal 'now'?
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Undergrad Some questions regarding the initial singularity
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High School Could Dark Matter Be the Fifth Fundamental Force of Nature?
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Undergrad Inflationary Energy: Origins & Conversion
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Graduate Do cosmologists take spontaneous symmetry breaking seriously?
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High School Does LIGO detect back ground noise
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Undergrad Perhaps an unknown property of gravity....
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High School Before the big bang video series
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High School How Did Light Originate After the Quark Epoch?
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Undergrad What Triggered the Big Bang Singularity's Expansion?
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Undergrad Hubble parameter in terms of the scale factor
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High School Could a New Field Explain Dark Matter's Role in the Universe?
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High School Some more basic questions on Dark Energy
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Undergrad How is motion in space different than motion in spacetime?
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High School How does the Universe's expansion relate to Newton's 1st law
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High School Explanation of the asymmetry of the Universe
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Undergrad What Does Absolute Magnitude in the B Filter of a Distant Galaxy Refer To?
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Undergrad Why is the density infinite at the singularity?
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High School What caused the uneven distribution of mass/energy?
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Undergrad Is Superdeterminism the Key to Understanding Our Universe?
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Graduate Can Dark Energy be eventually infinite?
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Undergrad How do I convert the number of efolds to conformal time during inflation?
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Undergrad How can the integral be rewritten using a change of variables?
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High School Hubble flow and velocity addition
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Graduate Whats the genesis of quantum foam,planck constant, & string
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Undergrad Difference between hubble sphere,particle horizon and event
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Undergrad What is the significance of the cosmological jerk in the expanding universe?
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Undergrad Is Infinity Inevitable in Our Understanding of the Universe's Beginning?
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Undergrad Where do high energy background photons go?
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Undergrad Can Unification of Forces Coexist with an Eternally Inflating Universe?
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High School Is the Speed of Light Dependent on the Size of the Universe?
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Undergrad Relations resolves singularity -- new paper on arxiv
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Undergrad How Similar Are the Images from BOSS and CMB Planck Spacecraft?
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Undergrad Is Dark Energy an Established Force in the Universe?
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High School Is the Universe Finite or Infinite?
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Undergrad Gravitational waves affected by gravity?
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Undergrad Night skies in a contracting universe, would they look blue?
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High School The big bang singularity and black hole singularity
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High School Is the Galileon theory an alternative to GR
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Undergrad Are Quantum Fluctuations Valid Causes for Universe Creation?
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Undergrad Center of the Universe: What Again
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High School Are universe and big bang considered to be the same thing?
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Undergrad Redshifts of galaxies and the expansion of the universe
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High School The speed of light and Hubble Flow
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High School Gravitational Waves & Dark Matter: Is There a Connection?
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Undergrad Physics & Objects Beyond Space & Time: Big Bang Singularity & Black Holes
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Undergrad Causally separated regions in CMB?
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High School If there is explosion with absence of oxygen?
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High School Acoustic Waves & Their Impact on Inflation: What You Need to Know
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Undergrad Why is an improbable early universe unacceptable?
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High School Calculating Time to Reach 100,000 Trillion Meters in Hubble Flow | PF Forum
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Undergrad Unraveling the Mystery: The Composition of Quasars
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Undergrad Universe is a sphere that is centered on any observer? How?
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Graduate How to convert between different mass measurements for CDM H
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Undergrad What Insights on Time in Physics and Cosmology Emerged from the Pi Conference?
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Undergrad Infinite Universe from Dimensionless SIngularity
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High School Is the Age of the Universe a Coincidence?
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Undergrad Could Dark Energy Be an Illusion of Spacetime Geometry?
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High School Who was the observer for the first 10 billion years?
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High School From a 4D perspective would 3D infinity exist?
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High School What is a quantum fluctuation....
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High School Understanding the Lagrange Points: What's Going Wrong with L2 and L3?
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High School How are neutrinos distributed in the universe?
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High School Are massive gravitons what ripple when galaxies collide?
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Undergrad Age of the Universe as Measured by a Non-Co-Moving Observer
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High School How can dark matter exist in a vacuum?
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High School How is the Age of the Universe Determined?
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High School Why is the age of the Universe finite?
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Undergrad Are Galaxies Moving Faster Than Light Due to Space Expansion?
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Undergrad What does "expansion of the universe" mean?
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Undergrad Time translation symmetry and the Big Bang
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Graduate Transition from opaque universe to release of CMB
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Undergrad Are Exotic Leptons Crucial for Life's Existence?
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High School What Causes the 2.7 Kelvin Temperature in the Vacuum of Space?
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High School Is dark matter a sea of massive photons?
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High School Is the Variable Speed of Light Theory a Viable Alternative to Inflation?
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Undergrad Detecting Entanglement in the Inflationary Potential: Is it Possible?
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High School The universe is crowded with black holes
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Insights Where Did the Big Bang Happen? - Comments
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High School Could the universe's Big Bang be 1D?
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High School Could LIGO Have Detected Dark Matter?
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Undergrad The Infinity of Days in the Eternity Universe
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Undergrad Is the total amount of gravity in the Universe conserved?
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Undergrad What are the Different Types of Multiverse Theories in Cosmology?
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High School Sgr A Relativistic Jets Visible?
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Undergrad Dark Energy - something from nothing?
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Undergrad Quantum Kinetic Energy of Neutrons, Protons and Electrons
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High School Hubble's Law: Explaining Why Distant Bodies Recede Faster
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High School Density of Black Holes: Unveiling the Universe's Secrets
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Undergrad Remote observer sees black hole evaporate
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Graduate Systematic study comparing cosmological models?
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Undergrad How can the universe expand faster than light?
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High School Is the universe expanding faster than expected
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Undergrad Different densities of the universe on different angles?
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High School Is Space Truly Expanding or Just a Pedagogical Tool?
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High School Infinite multiverse would contain the ridiculous?
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