A) As a purely random quantum fluctuation without a starting condition B) As an optical illusion caused by the movement of the Milky Way C) As resulting from an initial condition in which contents are flying apart D) As a contraction phase that has reversed into expansion
A) It accelerates the expansion indefinitely B) It has no effect on the scale factor C) It causes the universe to immediately begin contracting D) It gradually slows the expansion over time
A) They disappear over time B) Their density is too low C) Their gravitational constant is negative D) They are countered by the speed of light
A) Ultrarelativistic particles B) The cosmological constant alone without dark energy C) Dark energy D) Nonrelativistic matter
A) The pressure of dark energy B) The average separation between objects like galaxies C) The speed of light in a vacuum D) The total mass of the universe
A) It is exactly the same B) It is smaller C) It was infinite D) It is larger
A) It is larger B) It is always zero C) It is smaller D) It remains constant at 1
A) 20.000 ± 0.050 billion years ago B) 5.250 ± 0.010 billion years ago C) 10.500 ± 0.100 billion years ago D) 13.787 ± 0.020 billion years ago
A) One B) Negative one C) Infinity D) Zero
A) The universe reaching zero temperature B) The universe expanding at an infinite speed C) The universe stopping expansion and beginning to contract D) The universe maintaining a static size
A) FLRW metric B) Minkowski metric C) Kerr metric D) Schwarzschild metric
A) Schrödinger equations B) Friedmann equations C) Navier-Stokes equations D) Maxwell equations
A) How quantum particles decay into dark matter B) The geometric curvature of a static universe C) The exact temperature of the cosmic microwave background D) How the contents of the universe influence its expansion rate
A) Energy density B) Gravitational constant C) Speed of light D) Cosmological constant
A) Energy density within the universe B) Gravitational potential C) Scale factor derivative D) Pressure of the cosmic fluid
A) Density B) Parallax C) Period D) Pressure
A) Compression factor B) Cosmic constant C) Curvature parameter D) Speed of light
A) Deceleration limit B) Lambda baryon mass C) Cosmological constant D) Wavelength of radiation
A) Immediate contraction of the universe B) No effect on acceleration C) Deceleration of the expansion D) Infinite acceleration
A) It neutralizes gravity completely B) It accelerates expansion C) It stabilizes the scale factor D) It further decelerates expansion
A) Sufficiently negative pressure with p < -ρc²/3 B) Zero pressure like nonrelativistic matter C) Infinite positive pressure D) Positive pressure equal to ρc²/3
A) Nonrelativistic matter B) Photon gas density C) The cosmological constant D) Ultrarelativistic particle gas
A) It equals the speed of light squared B) It has extreme negative pressure C) It is essentially pressureless D) It has extreme positive pressure
A) Pressure is greater than ρc² B) Pressure is exactly equal to ρc² C) Pressure is negative and exceeds ρc² D) Absolute pressure is much less than ρc²
A) Hydrogen gas B) Neutron gas C) Dark matter gas D) Photon gas
A) p = -ρc²/3 B) p = -ρc² C) p = 0 D) p = ρc²/3
A) No B) Only in laboratory settings C) Yes, through direct particle accelerators D) Yes
A) From the laws of thermodynamics in a closed box B) From quantum mechanical calculations alone C) From astronomical observations D) From direct laboratory synthesis
A) ä = 1 B) ä = 0 C) ä < 0 D) ä > 0
A) Einstein's theory B) Hubble's law C) Kepler's law D) Newton's law
A) The same everywhere B) Constantly changing C) Composed of a single element D) The same in all directions
A) Logarithmically B) Uniformly C) Asymmetrically D) Chaotically
A) Inverse relationship B) Exponential relationship C) Linear relationship D) Quadratic relationship
A) Positions B) Accelerations C) Temperatures D) Time intervals
A) t0 B) x0 C) v0 D) H0
A) The Friedmann-Lemaître model B) The Lambda-CDM model C) The inflation model D) The Big Bang metric
A) Dark energy acceleration B) Inflation C) Redshifting D) Late-time acceleration
A) Vesto Slipher B) Alexander Friedmann C) Knut Lundmark D) Edwin Hubble
A) Walter Baade B) Knut Lundmark C) David Spergel D) Adam Riess
A) Knut Lundmark B) Georges Lemaître C) Edwin Hubble D) Vesto Slipher
A) David Spergel B) Edwin Hubble C) Walter Baade D) Wendy Freedman
A) Wendy Freedman's B) Adam Riess's C) David Spergel's D) Knut Lundmark's
A) 73±7 km⋅s-1⋅Mpc-1 B) 80±17 km⋅s-1⋅Mpc-1 C) 67±7 km⋅s-1⋅Mpc-1 D) 72±5 km⋅s-1⋅Mpc-1
A) Galaxy diameter measurements B) Visual-band light-curve shapes C) Cepheid variable calibrations D) Cosmic microwave background analysis
A) 73±7 km⋅s-1⋅Mpc-1 B) 80±17 km⋅s-1⋅Mpc-1 C) 72±5 km⋅s-1⋅Mpc-1 D) 67±7 km⋅s-1⋅Mpc-1
A) 80±17 km⋅s-1⋅Mpc-1 B) 67±7 km⋅s-1⋅Mpc-1 C) 50 to 90 km⋅s-1⋅Mpc-1 D) 73±7 km⋅s-1⋅Mpc-1
A) Adam Riess's B) Alexander Friedmann's C) Wendy Freedman's D) David Spergel's
A) Lemaître Space Observatory B) Hubble Space Telescope C) Wilkinson Microwave Anisotropy Probe satellite (WMAP) D) Slipher Explorer
A) 80±17 km⋅s-1⋅Mpc-1 B) 73±7 km⋅s-1⋅Mpc-1 C) 67±7 km⋅s-1⋅Mpc-1 D) 72±5 km⋅s-1⋅Mpc-1
A) Spherical coordinates B) Cartesian coordinates C) Comoving coordinates D) Relativistic coordinates
A) Three-dimensional spacetime B) Infinite-dimensional spacetime C) Five-dimensional spacetime D) Four-dimensional spacetime
A) Three-dimensional spatial surfaces B) Four-dimensional temporal surfaces C) One-dimensional linear curves D) Two-dimensional flat planes
A) Cylinders B) Tori C) Hyperboloids D) Spheres
A) Gravity B) Dark matter density alone C) Thermal radiation D) Electromagnetism
A) Geometrically flat B) Open hyperboloids C) Closed spheres D) Irregularly curved
A) 180 degrees B) 90 degrees C) 360 degrees D) 270 degrees
A) Infinite age B) Zero age C) Cyclical age D) Finite age
A) Event horizon B) Cosmic horizon C) Hubble horizon D) Particle horizon
A) Because stars burn out too quickly B) A cosmic event horizon induced by repulsive gravity C) Due to excessive magnetic fields D) Because light travels infinitely slowly
A) Particle horizon B) Event horizon C) Planck scale D) Hubble horizon
A) The Doppler effect B) Thermal expansion C) Photon decay D) Gravitational lensing
A) They concentrate B) They multiply C) They dilute D) They annihilate
A) rho B) p C) w D) a
A) Zero B) One-third C) Negative one D) Negative three
A) Around 1026 seconds B) At the very end of the universe C) Around 10−32 seconds D) Around 1 second
A) Ultrarelativistic particles B) The inflaton C) Magnetic monopoles D) Neutrino decoupling
A) A negative-energy true vacuum state B) A fluctuating thermal vacuum state C) A positive-energy false vacuum state D) A zero-energy stable vacuum state
A) Magnetic monopoles B) Cosmic scale factors C) Standard Model particles D) Inflaton fields
A) Thermal radiation B) Magnetic monopoles C) Quantum fluctuations D) Neutrino decoupling
A) About 1026 B) About 1060 C) About 1 D) About 1032
A) Inflation B) The horizon C) Radiation D) Quantum fluctuations
A) About e60 seconds B) About 1026 seconds C) About 1 second D) About 10−32 seconds
A) Neutron stars B) Cosmic microwave background C) Nonrelativistic matter D) Dark energy
A) Radiation era B) Dark energy epoch C) Matter-dominated epoch D) Inflationary epoch
A) By measuring gravitational lensing angles B) Through time-delay cosmography C) Using its apparent brightness D) Through the redshift
A) Type Ia supernovae B) Cepheid variable stars C) Neutron stars D) Lensed quasars
A) Cepheid variable photometry B) Time-delay cosmography C) CMB fluctuation sizing D) Redshift drift analysis
A) TDCOSMO cluster B) Planck foreground cluster C) MACS J0138-2155 D) H0LiCOW cluster
A) GW170817 B) SN Refsdal C) SN Requiem D) MACS J0138-2155
A) CMB fluctuation sizes B) Gravitational lensing time delays C) Redshift drift D) Standard candle brightness
A) Square Kilometre Array or Extremely Large Telescope B) Cepheid variable telescopes from Hubble's era C) H0LiCOW and TDCOSMO space probes D) Planck collaboration satellites
A) An infinite Euclidean universe B) A preferred rest frame C) A universal center D) A static spacetime
A) Only on small scales B) Yes C) Only in flat spacetimes D) No
A) General relativity B) Quantum mechanics C) Electromagnetism D) Special relativity
A) Andrew R. Liddle B) Arthur Eddington C) Delo E. Mook D) Charles H. Lineweaver
A) Press Syndicate of the University of Cambridge B) Scientific American C) Princeton University Press D) Cambridge University Press
A) March 2000 B) March 1931 C) March 1991 D) March 2005
A) David H. Lyth B) Tamara M. Davis C) Thomas Vargish D) Andrew R. Liddle |