All that we really need to plot out the future of our universe are a few good measurements. This does not mean that we can sit down today and outline the future course of the universe with anything like certainty. There are still too many things we do not know about the way the universe is put together. But we do know exactly what information we need to fill in our knowledge, and we have a pretty good idea of how to go about getting it.
Perhaps the best way to think of our present situation is to imagine a train coming into a switchyard. All of the switches are set before the train arrives, so that its path is completely determined. Some switches we can see, others we cannot. There is no ambiguity if we can see the setting of a switch: we can say with confidence that some possible futures will not materialize and others will. At the unseen switches, however, there is no such certainty. We know the train will take one of the tracks leading out, but we have no idea which one. The unseen switches are the true decision points in the future, and what happens when we arrive at them determines the entire subsequent course of events.
When we think about the future of the universe, we can see our "track" many billions of years into the future, but after that there are decision points to be dealt with and possible fates to consider. The goal of science is to reduce the ambiguity at the decision points and find the true road that will be followed.
What does the author see as the function of the universe’s unseen "switches"

A:They tell us which one of the tracks the universe will use. B:They enable us to alter the course of the universe. C:They give us information about the lunar surface. D:They determine which course the universe will take in the future.

According to the passage, it is difficult to be certain about the distant future of the universe because we ______.

A:have too many conflicting theories B:do not have enough funding to continue our research C:are not sure how the universe is put together D:have focused our investigations on the moon and planets

What does the author see as the function of the universe's unseen "switches"

A:They tell us which one of the tracks the universe will use. B:They enable us to alter the course of t he universe. C:They give us information about the lunar surface. D:They determine which course the universe will take in the futur

What does the author see as the function of the universe' s unseen "switches"

A:They tell us which one of the tracks the universe will use. B:They enable us to alter the course of universe. C:They give us information about the lunar surface. D:They determine which course the universe will take in the futur

What does the author see as the function of the universe's unseen "switches"

A:They tell us which one of the tracks the universe will use. B:They enable us to alter the course of t he universe. C:They give us information about the lunar surface. D:They determine which course the universe will take in the future.

According to the passage, it is difficult to be certain about the distant future of the universe because we ______.

A:have too many conflicting theories B:do not have enough funding to continue our research C:are not sure how the universe is put together D:have focused our investigations on the moon and planets

How the first stars formed from this dust and gas has been a burning question for years, but a state-of-the-art computer simulation now offers the most detailed picture yet of how these first stars in the universe came into existence, researchers say.
The composition of the early universe was quite different from that of today, and the physics that governed the early universe were also somewhat simpler. Dr. Naoki Yoshida and colleagues in Japan and the U.S. incorporated these conditions of the early universe, sometimes referred to as the "cosmic dark ages," to simulate the formation of an astronomical object that would eventually shine its light into this darkness.
The result is a detailed description of the formation of a protostar--the early stage of a massive primordial star of our universe, and the researchers’ computer simulation, which has been called a "cosmic Rosetta Stone" sets the bar for further investigation into the star formation process. The question of how the first stars evolved is so important because their formations and eventual explosions provided the seeds for subsequent stars to come into being.
According to their simulation, gravity acted on minute density variations in matter, gases, and the mysterious "dark matter" of the universe after the Big Bang in order to form this early stage of a star-a protostar with a mass of just one percent of our sun. The simulation reveals how pre-stellar gases would have actually evolved under the simpler physics of the early universe to form this protostar.
Dr. Yoshida’s simulation also shows that the protostar would likely evolve into a massive star capable of synthesizing heavy elements, not just in later generations of star, but soon after the Big Bang.
"This general picture of star formation, and the ability to compare how stellar objects form in different time periods and regions of the universe, will eventually allow investigation into the origins of life and planets," said Lars Hernquist, a Professor of Astronomy at Harvard University and a coauthor of this latest report. "The abundance of elements in the universe has increased as stars have accumulated," he says, "and the formation and destruction of stars continues to spread these elements further across the universe. So when you think about it all of the elements in our bodies originally formed from nuclear reactions in the centers of stars, long ago."
Their simulation of the birth of a protostar in the early universe signifies a key step toward the ambitious goal of piecing together the formation of an entire primordial star and of predicting the mass and properties of these first stars of the universe. More powerful computers, more physical data, and an even larger range will be needed for further calculations and simulations, but these researchers hope to eventually extend this simulation to the point of nuclear reaction initiation when a stellar object becomes a true star.
"Dr. Yoshida has taken the study of primordial star formation to a new level with this simulation, but it still gets us only to the halfway point towards our final goal. It is like laying the foundation of a skyscraper," said Volker Bromm, Assistant Professor of Astronomy at the University of Texas, Austin and the author of a companion article. "We must continue our studies in this area to understand how the initially tiny protostar grows, layer by layer, to eventually form a massive star. But here, the physics become much more complicated and even more computational resources are needed./
According to the last paragraph, all of the following are goals of the simulation project EXCEPT______.

A:to know more about the mass and properties of the first stars of the universe B:to simulate the process of how the early universe began C:to apply the simulation to the study of nuclear reaction initiation D:to discover the truth about the formation of a protostar