How do we determine the conditions that existed in the early universe?
A) We work backward from current conditions to calculate what temperatures and densities must have been when the observable universe was much smaller in size.
B) We look all the way to the cosmological horizon, where we can see the actual conditions that prevailed all the way back to the first instant of the Big Bang.
C) The conditions in the very early universe must have been much like those found in stars today, so we learn about them by studying stars.
D) We can only guess at the conditions, because we have no way to calculate or observe what they were.
A) We work backward from current conditions to calculate what temperatures and densities must have been when the observable universe was much smaller in size.
You might also like to view...
Two coherent waves reach the same point in phase. One wave has amplitude 8 units and the other has amplitude 6 units. The amplitude of the superposed wave is ______ units.
A. 6 B. 8 C. 10 D. 14 E. 2
If a cast iron has the designation 60-40-18, the yield strength is equal to _________psi.
Fill in the blank(s) with the appropriate word(s).
The structure of most galaxies is most apparent using near-infrared images that show the locations of ____
a. dense molecular clouds b. spiral tracers c. atomic hydrogen clouds d. cool, low-luminosity stars e. hot, high-luminosity stars
The intensity of radiation reaching the Earth from the Sun is 1350 W/m2. The Earth's radius is 6.4 × 106 m. How big a force does this radiation exert on the Earth? (Assume it is all absorbed.)
A. 5.8 × 108 N B. 1.2 × 109 N C. 2.3 × 109 N D. 4.6 × 109 N E. 1.7 × 1017 N