WHITE HOLES AND WORMHOLES
According to a list of frequently asked questions answered by Ted Bunn at a website of the University of Berkeley, white holes and wormholes can be concieved of and are mathematically possible, so it is possible that they could exist. I learned the following from the previously mentioned site. The equations of general relativity are symmetric in time. If one assumes that time moves backwards instead of forwards, on can get an equally valid solution that is exactly opposite of a black hole, called a white hole. This means that if time is reversed, a white hole will only spit things out, whereas a black hole will only take things in. Although this can be conceived of as possible, it is almost certain that these things do not exist, since it is impossible to produce. Producing a white hole is as impossible as destroying a black hole, because of time.
A wormhole exists when a black hole is connected to a corresponding white hole. It is theorized that the white hole may be in a different universe, which is defined as being a space-time that is completely disconnected from our region except by a wormhole. In theory, a wormhole could lead to anywhere- perhaps to another universe or perhaps in the past. However, it is almost certain that wormholes do not exist. Black holes that form from the collapse of ordinary matter do not form wormholes, and scientists do not think it is possible for any other type of black hole to exist. Also, if a wormhole formed, it would probably not be stable, and would collapse if anything tried to move through it. Even if it were stable, if one tried to pass through it one would be “fried” by the concentrated light waves of the stars and the cosmic microwave background.

FALLING INTO A BLACK HOLE
I found a very interesting series of frequently asked questions answered by Ted Bunn at The University of Berkeley’s website. An interesting question is “What if I fall into a black hole?” I learned the following answer from the FAQs at the previously mentioned website. If one aims a spaceship at the million-solar-mass black hole in the middle of the Milky Way Galaxy, being on the spaceship as it coasts in wouldn’t feel anything at first. As one gets closer one feels tidal gravitational forces. Eventually they will tear one apart. If one looks out as they are falling into the black hole, one would see everything distorted, because the gravity of the black hole bends light. Noone on the outside would be able to see you, because the light can’t escape the horizon of the black hole. Now this part is extremely fascinating: if your friend saw you fall into a black hole, she would see you move more and more slowly. She would never actually see you hit the black hole’s horizon, even if she waited forever. This is because the light one emits takes longer and longer to escape the black hole and reach your friend as you fall in. The light you emit as you cross the horizon of the black hole will remain frozen in space forever.

WHAT IF WE CONTACT ALIENS?
I read an article by Seth Shostak at the website of SPACE, and learned the following information. On July 18, 2006 the Alien Telescope Array was put to work. It is a group of telescopes searching for a signal from alien societies. Over the next twenty years the telescopes will pan 1,000 light years away from us in all directions. If there is life out there, we are now more likely to find it. But what if we do get a signal? Will the general public ever know it? Or would the government keep it a secret? There are many assumptions of what would happen if we got a signal. Among them are that the government would keep it a secret, or that scientists would keep it a secret. But there is actually a protocol for action in case a signal is found. The protocol is that scientists must first determine with certainty that the signal is extraterrestrial. Then they must tell all other astronomers and national officials, and then tell the world.It is not quite as simple as it sounds. Scientists actually get signals all the time, and they spend much of their time sorting through these signals to be sure that they aren’t caused by aliens. And if there is a possibility of alien signals, the media will be reporting about it weeks before the scientists can be certain that it is a signal from aliens.

WHY WE MUST LEAVE EARTH
Perhaps you are familiar with Stephen Hawking, a scientist who has made astounding leaps in the study of time, space and black holes. He is considered to be an extremely reliable source for scientific speculation. Well, he recently made an argument in favor of space colonization. I recently read an article called “Why We Must Flee the Planet: The Geometry of Earth is All Wrong” at the website of SPACE. I learned the following information from that article.
Stephen Hawking is an advocate of space colonization. According to the previously mentioned article, Stephen Hawking stated that “Life on Earth is at the ever-increasing risk of being wiped out by a disaster, such as sudden global warming, nuclear war, a genetically engineered virus or other dangers.”
Seth Shostak, the author of the article, asserts that another reason that life on Earth is impractical is because the shape of Earth is inefficient. A sphere has minimal surface area, while a square has maximum surface space. He claims that the population of humans doubles every fifty years, and that in 4810 CE the mass of humans would reach the moon. A physicist named Freeman Dyson suggests that humans move to asteroids in the Kuiper Belt, a band of asteroids and space junk surrounding the solar system.
Seth Stostak argues that moving to solar system bodies is not practical, for a planet like Mars “is not a cheap fixer-upper.
Another possibility seems much more practical: that humans construct huge aluminum cylinders in space and live in them. In the 1970’s some scientists predicted that by the year 2000 millions of humans would be living in space. Of course, that may yet come to pass.

DARK MATTER AND DARK ENERGY MAY BE THE SAME THING
I am fascinated by dark matter as well as dark energy, and this is the first time I have come across a suggestion that they may be the same thing. An article at the website of SPACE by Robert Roy Britt explores the possibility. I learned the following from the article.
The article asserts that dark matter and dark energy comprise 96% of all mass and energy in the universe. Imagine how this limit our ability to study the whole universe. We are not able to study very much of the universe at all. Scientists don't know what either dark energy or dark matter is. The astronomer Robert Scherrer suggests that they are caused by the same phenomenon.
Dark matter was imagined decades ago to solve the question of why galaxies stay together, given that being made of normal matter alone they would fly apart. Scientists theorized that there must be some unknown matter that forms invisible objects that hold galaxies together with their gravity. Dark energy, on the other hand, was concieved of in the last decade. It was imagined to be a force like the opposite of gravity, that must be pushing all objects apart. This theory was accepted because it had become known that the universe expanding at an ever-faster rate.
Robert Sherrer has a theory to explain both dark matter and dark energy. He suggests that there is a form of energy called a scalar field. It has energy and pressure and a magnitude, much like a magnetic field. As the previously mentioned article from SPACE states, "A scalar field has no direction. A scalar field is thought to have been behind inflation, the less-than-a-second period after the Big Bang when the universe expanded many billions of times before settling into a more reasonable rate of growth."
He suggests the presence of what other astrophysicists have theorized as being a kind of kinetic energy, called K-essence. K-essence in Scherrer's theory clumps early on to help form galaxies, and now forces the universe apart. According to the article at SPACE, "'Dark matter has a density that decreases as the universe expands', Sherrer explained, 'while dark energy has a density that stays constant as the universe expands. That means that at very early times, the dark matter 'piece' of the k-essence is the dominant one,' Scherrer said. 'As the universe expands and the density of the dark matter 'piece' of the k-essence decreases, it eventually falls below the density of the dark energy 'piece,' and the k- essence behaves more like dark energy.'"
Now this part is really fascinating. Imagine a fifth dimension of other universes alongside ours.
Sherrer suggests confining our universe to a four-dimensional plane known as a membrane, that is in between other membranes of other universes. And imagine that gravity belongs to a fifth dimension that's perpendicular to our universe's plane/membrane. Dark matter would be the gravitational influence of other membranes on ours. It has also been suggested that membranes give a new explanation of the Big Bang. According to this theory another membrane collided with ours, releasing energy and heat and leading to the expansion of our universe. The popular String Theory suggests that dark matter is not related to dark energy but is rather an exotic form of matter known as supersymmetric perticles. And this is very exciting: In 2007, a particle accelerator called the Large Hadron Collider will produce supersymmetric particles, if they exist. I can't wait to report on that.

DEEP THOUGHTS
Blair Rothstein states, "It is odd that we will never truly know how it began. We can only speculate and give our best guess. Through our own devices we have been able to produce evidence that these guesses are close to the truth. But centuries from now, will the human race compare us to those who once thought of the Earth as the center of the universe?"
This thought makes me wonder what we will discover if we can only break free of the confines of our five senses. We have overcome the limits of our eyes; we have created telescopes and ways of detecting light waves beyond the visible spectrum, and we have created microscopes. We have learned to detect the world around us through deductive reasoning given evidence. We have not come to understand our brains and it seems to me that coming to understand our brains will be the first step in overcoming the limits of our brains. The brain is like a riddle or a puzzle meant for us to solve and understand so that we may grow. It makes me wonder what gave us such a puzzle and what must await us when we know it. It is human nature that what we learn we will use as a tool. Perhaps the secrets of the universe are a matter of understanding our own brains and bodies so that we can have new ways of perception beyond the five senses.

THE UNIVERSE IS EXPANDING
I learned in a class called Descriptive Astronomy that the universe is expanding. Before I begin I would like to say that to me the information I am about to relate is contradictory. Bear this in mind while reading: How can anyone claim that the universe is expanding forever and also claim that our galaxy will be alone in the universe in just 100 billion years? Nonetheless, here is what I learned from an article at the site of NASA.Scientists surveyed the cosmos and measured temperature differences. They detected light created only 379,000 years after the Big Bang, which is an astonishingly short period of time considering the age of the universe. This evidence fits theoretical models of the universe, and so scientists can claim that the universe is indeed expanding, and that it will continue to grow forever.
According to NASA, "The universe is 'flat' in cosmological parlance. In fact, not only won't there be a "Big Crunch", the evidence points to the possibility of a "Big Rip" when the expansion of the universe accelerates. Dark energy, which accounts for roughly 70% of the mass of the universe, has weird gravity that is the opposite of what we know. The gravity that we know attracts; dark energy's gravity repels."
If scientists are right and the universe is continuing to expand and accelerate, our galaxy will be alone in the universe in 100 billion years. That is to say that all other galaxies will be pushed beyond the point of visibility and we won't be able to see them anymore.