Exam 22: The Birth of the Universe

Refer to this scenario for the following questions: Lost in Spacetime.Just when you thought it was safe to take final exams ...a vindictive multi-dimensional being reaches down (up? over? through?)to Earth and pulls you out of the universe.You are thrown back into the universe at a place of this being's choosing,and she permits you to leave only after you have identified your surroundings.You are subject to several tests. Through a scientifically unexplainable miracle,you are able to survive in every one of the places you are tested.(Lest you become too comfortable,however,you certainly are able to feel any associated pain due to high temperature,pressure,gravity,etc. )In each case described below,identify your surroundings.In some cases,the surroundings described may exist only during eras of the universe (past or future)other than our own time;in those cases,you should identify both the place and the time where you are located. -It sure is bright everywhere;you've been able to travel around a bit,and it's clear that you are not in a star.Yet it is as bright as looking directly at the Sun.In your extensive travels through your current surroundings,you cannot find a single neutral atom anywhere,nor can you find a nucleus besides hydrogen or helium.And,while it is hot (a few thousand degrees Kelvin),it is nowhere near the temperature needed for nuclear fusion.Where are you?

The fact that the sky is dark at night shows that the observable universe cannot extend forever.

In principle,if we could see all the way to the cosmological horizon we could see the Big Bang taking place.However,our view is blocked for times prior to about 380,000 years after the Big Bang.Why?

The Big Bang theory seems to explain how elements were formed during the first few minutes after the Big Bang.Which hypothetical observation below (these are not real observations)would call our current theory into question?

Refer to this scenario for the following questions: Lost in Spacetime.Just when you thought it was safe to take final exams ...a vindictive multi-dimensional being reaches down (up? over? through?)to Earth and pulls you out of the universe.You are thrown back into the universe at a place of this being's choosing,and she permits you to leave only after you have identified your surroundings.You are subject to several tests. Through a scientifically unexplainable miracle,you are able to survive in every one of the places you are tested.(Lest you become too comfortable,however,you certainly are able to feel any associated pain due to high temperature,pressure,gravity,etc. )In each case described below,identify your surroundings.In some cases,the surroundings described may exist only during eras of the universe (past or future)other than our own time;in those cases,you should identify both the place and the time where you are located. -You are once again in a hot,dense place.You are surrounded by protons and neutrons,some rapidly fusing into helium.You notice that your surroundings are cooling (good,because it's really hot!)and rapidly dropping in density.Within about 3 minutes,the fusion reactions stop.Where are you?

According to the Big Bang theory,how many forces-and which ones-operated in the universe during the GUT era?

Based on the results from Planck,the overall composition of the universe is

Which forces have physicists shown to be the same force under conditions of very high temperature or energy,as confirmed by experiments in particle accelerators?

Briefly explain how Hubble's discovery of a relationship between galactic distance and redshift led to the idea of the Big Bang.

Evidence that the cosmic background radiation really is the remnant of a Big Bang comes from predicting characteristics of remnant radiation from the Big Bang and comparing these predictions with observations.Four of the five statements below are real.Which one is fictitious?

The theory that inflation occurred in the early universe is incompatible with the theory of relativity.