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 How do we know that 74% of the universe is dark energy?
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Graduate Redshift Time and the Start of the Solar System
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High School Need Help Understanding Expanding Universe
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Undergrad The First Three Minutes - Steven Weinberg
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Graduate Mirror neutrons all over the science news
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Graduate Size of universe and quantity of mass
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Undergrad 10^80 particles in observable v unobservable universe
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Graduate Mission to Probe the Universe's Darkest Secrets
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Graduate Is the inverse-square law valid for all cosmological distances?
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Graduate Carried along by the Hubble flow.
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Graduate Tugs from Beyond the Observable Universe
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Graduate How does the graph of V(φ) support the concept of slow-roll inflation?
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Graduate Spacetime for an anti-black hole?
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Graduate Is the Universe Leaking Energy? Tamara M. Davis
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Graduate What causes angular momentum in rotating bodies
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Graduate Is it possible that antimatter would exert antigravity on matter?
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Graduate Does Dark Matter Gather Near Black Holes and Suns?
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Undergrad Question About Light From the Big Bang
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Graduate What Does t→0 Mean in Neutron Freeze-Out?
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Undergrad Was There Matter or Energy at the Start of the Big Bang?
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Graduate Neutron escaping to parallel universe
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Graduate The Shape of the Universe: What is a Flat Universe?
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High School Need Research Question Related to Multiverse (High School Level)
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High School What should we call other universes besides 'parallel universes'?
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Graduate Does the Total Energy of a Black Hole Change During Evaporation?
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Graduate Is our universe the unique possible outcome of the big bang
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Graduate Is the speed of light the limit of our universe?
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Graduate 'Density' of 2.73K Cosmic Microwave Background
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Graduate Can there be a place in space where no gravity exists?
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Undergrad Shape of Universe: Why Is It Not Spherical?
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Graduate Why isn't the universe a big black hole?
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Graduate From Boomerang to Planck: reading the ancient light
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Graduate Questions about Parallel Worlds by Michio Kaku: the big bang
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Graduate Could the Visible Universe Be a Fuzzball in String Theory?
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Graduate Multiple collections of energy, very far apart
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Graduate Can Different Vacuum States in Curved Spacetime Appear Thermal to Each Other?
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Graduate Understanding the Scale Factor in the Friedman Equation | Cosmology Explained
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Graduate Understanding the Density Parameter in Cosmology: Matts Roos' Text Explanation
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Graduate What Happens If We Travel in One Direction in the Universe?
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Graduate Higgs Field, Big Bang, and Spacetime
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Graduate How Does an Infinite Static Arrangement Collapse Under Gravity?
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Graduate Could a new type of compass be created using a rotating permanent magnet?
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Graduate The WMAP objective is to measure the temperature differences in the
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Graduate The big bang model, time, and general relativity
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Graduate Are objects disappearing as the universe expands?
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Graduate Cosmic Microwave Background Radiation, why from 380,000?
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Graduate Unraveling the Mystery: Superstring Theory and the Timeline Before the Big Bang
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Graduate Is Time an Irrational Concept in Space-Time Understanding?
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Graduate The flatness of the observable and unobservable univ
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Graduate Can alternate radiation model explain redshift?
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Graduate What are the jets from a feeding blackhole made of?
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High School Do objects within a galaxy rotate in the same direction as the galxy itself?
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Graduate How Does Chaplygin Gas Unify Dark Energy and Dark Matter?
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Graduate What the Hubble constant must be set to if Univ is flat
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High School Possible matter being Created/Destroyed?
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Graduate Real-Space vs Redshift-Space Correlation Functions
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Undergrad Does Time Flow Differently in Distant Galaxies Due to Speed?
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Graduate Do cyclic models of the universe
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Graduate Blackbody Radiation: Solving Introduction to Cosmology Eq. #25
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Graduate Article: Every black hole contains a new universe
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Graduate By what equation do physicists use to measure the time before the CMB
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Graduate How is Cosmological Proper Distance Defined and Interpreted in Physics?
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High School I would like to learn more about cosmology
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Graduate Is Dark Energy the Same as Vacuum Energy?
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Graduate How can they rule out a closed universe?
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Undergrad Did Olympus Mons Cause Mars' Lack of Electromagnetic Field?
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Graduate How new are carbon chem and rocky planets?
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Graduate We live at the beginning of the time when life is possible
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Graduate Black holes and an argument I'm in
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Graduate Why does inflation lead to a smaller universe at 380000 years?
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Graduate How big do we need for comsological principle?
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Graduate Is Dark Matter Really Missing in Our Galactic Neighborhood?
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Graduate Confused about the formation of Stuff in an Isotropic-ish Universe
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Undergrad Is the Universe Really Expanding Without a Center?
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High School Big Bang Skeptic: Constructing a Ring-like Universe
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High School Is there truly no center to the universe?
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Undergrad The Expanding Universe: Evidence for Raisin Bread Baking Effect
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Graduate What exactly is a quantum fluctuation
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Graduate Lawrence Krauss: Observing a Baby Universe's Expansion
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Graduate Science bits of Hawking's documentary
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Graduate Q and U parameters for polarization
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Graduate Stephen Hawking's did god Create the Universe discovery documentary
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Graduate Why is the CMB power spectrum often plotted as l(l+1) C_l and not only C_L ?
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Graduate Quantum Mechanics and Thermodynamics Explain Us
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Undergrad What Are the Key Flaws in the Big Bang Theory?
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The balloon analogy (please critique)
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Graduate Does the Universe Have a Circular Structure?
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Weird Face In the Pillars of Creation?
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Graduate Is the number of atoms the same as during the Big Bang
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High School Did the heaviest elements come from other galaxys
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High School Planets & Galaxies: Movement Patterns Explained
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Graduate Can Space-Time Events Be Quantized Before the Big Bang?
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Undergrad Far away galaxies moving faster than light?
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Graduate Viewing a far away galaxy through a wormhole
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Graduate Update to the BALLOON ANALOGY web page
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High School Need Big Bang Theory Evidence for a school debate.
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Graduate How Can We Measure Earth's Speed Relative to the Big Bang?
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Undergrad Is a Multiverse Considered a Universe or Multiple Universes?
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Graduate Gravity speed (I know it's been beat to death, apologies in advance)
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Graduate Density fluctuations that result after inflation
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