Some people wish that we lived in a recollapsing universe that would eventually stop expanding and start contracting. For this to be the case, which of the following would have to be true (based on current understanding)?
A) Dark energy is the dominant form of energy in the cosmos.
B) Dark energy does not exist and there is much more dark matter than we are aware of to date.
C) Neither dark energy nor dark matter really exist.
D) Dark energy exists but dark matter does not.
Question 2
Which of the following statements about scientific theories is false?
A) Theories are not taken seriously if they contradict older, more developed, theories.
B) A theory is a model designed to explain a number of observed facts.
C) If even a single new fact is discovered that contradicts what we expect according to a particular theory, then the theory must be revised or discarded.
D) A theory must make predictions that can be checked by observation or experiment.
E) A theory can never be proved beyond all doubt; we can only hope to collect more and more evidence that might support it.
The Scales of the Universe
Structure of the Early Universe
Big Picture of the Evolution of the Universe
Earth Affects People; People Change Earth
The first commercially successful typewriter, manufactured in quantity beginning in 1874, surely fue
Older people who experienced stressful events in their younger years may show personal growth and ...