Stephen W. Hawking

"We should seek the greatest value of our action"

external image 600full-stephen-w.-hawking.jpg

external image The+Universe+in+a+Nutshell+-+Stephen+Hawking.jpgexternal image the_grand_design_cover.jpgexternal image a_brief_history_of_time.jpg

Background Information: Exploring Our Universe
Some questions in life we will never be able to answer, yet they continue to eat away at us everyday until we can fathom up a sizeable answer. For Stephen Hawking, his fascination began in the world around him and expanded into the wonders of our universe. Troubling himself with the questions,"Where do we come from? How did the universe begin? Why is the universe the way it is? How will it end?", he still tries to formulate a solution and change how we look at the world.

"All my life, I have been fascinated by the big questions that face us, and have tried to find scientific answers to them. If, like me, you have looked at the stars, and tried to make sense of what you see, you too have started to wonder what makes the universe exist. The questions are clear, and deceptively simple. But the answers have always seemed well beyond our reach. Until now.

"The ideas which had grown over two thousand years of observation have had to be radically revised. In less than a hundred years, we have found a new way to think of ourselves. From sitting at the center of the universe, we now find ourselves orbiting an average-sized sun, which is just one of millions of stars in our own Milky Way galaxy. And our galaxy itself is just one of billions of galaxies, in a universe that is infinite and expanding. But this is far from the end of a long history of inquiry. Huge questions remain to be answered, before we can hope to have a complete picture of the universe we live in.

"I want you to share my excitement at the discoveries, past and present, which have revolutionized the way we think. From the Big Bang to black holes, from dark matter to a possible Big Crunch, our image of the universe today is full of strange sounding ideas, and remarkable truths. The story of how we arrived at this picture is the story of learning to understand what we see."(1)

external image the-universe-1-ray.jpg

Stephen Hawking was born on January, 8 1942 in Oxford, England. Naturally, he had shown a passion for science even as a child, especially when it came to astronomy. It seemed that Hawking could never get his head out of the sky. In his early years, Hawking enrolled into the University of Cambridge where he began to study cosmology. However, in sight of his dreams, Hawking at age 21 was diagnosed with Amoyotrophic Lateral Sclerosis (ALS or Lou Gehrig's Disease). Despite this debilitating illness, throughout life, he has continually produced ground-breaking work in physics and cosmology along with writing several books, most notably A Brief History In Time (1988), followed by The Universe In a Nutshell (2001) and including a collection of essays entitled Black Holes and Baby Universes (2001). Fighting his illness, Hawking has realized that there were still things he could accomplish in his life and it was this level of passion for life itself that pushed him on to achieve a degree of genius in science comparable to that of Albert Einstein. Hawking, with the help of modern technology, has brought science to a new level especially in regards to his findings about black holes which have helped reshape many scientific theories behind the underlying questions of the universe. With this said, it is clearly evident that throughout his career he has come a long way in his goal to make science more accessible to society.

Research on Black Holes: Hawking Radiation
Image of the black hole found in the center of the milky way galaxy.
Image of the black hole found in the center of the milky way galaxy.

For Hawking, recognition would come in 1974 at the age of 32, when he finally struck gold in his research.Black holes, initially discovered by Einstein in his theory of general relativity, were found to be "a region of space that is so incredibly dense that not even light can escape the surface." (2) This region is known as a vacuum, following the theory of general relativity, where the energy inside acts as a repulsive force which works in driving objects further apart as gravity attempts to pull them together. It is believed that if energy within the vacuum is high enough, the black hole will produce a level of repulsion that would in turn speed up time thus explaining the expansion of our universe. These findings, most notably from cosmologist Roger Penrose, intrigued Hawking in his quest to uncover how the universe began. To start his research Hawking studied stellar-mass black holes, which are the most common and are formed when a cluster of stars (usually 10-15 times the mass of the Sun) run out of nuclear fuel in their core causing them to collapse into a supernova. This supernova expels energy through nuclear fusion, during this process creating a hole in the observable universe. These "invisible" holes left scientists with little to study causing them to believe that black holes were nothing more than information vacuums that consume all matter around them. That was until Hawking "was able to demonstrate, that matter, in the form of radiation, can escape the gravitational force of a collapsed star." (3)
Binary system with an accretion disk around a stellar-mass black hole being fed by material from the companion star.
Binary system with an accretion disk around a stellar-mass black hole being fed by material from the companion star.

This demonstration led Hawking to discover that there are real particles outside the horizon of a black hole which were created from gravitational potential energy. Once created these real electrons and positrons are set into motion only to collide, this continual process inside the black hole produces real photons that are radiated into space. This effect predicted by Stephen Hawking is know as Hawking Radiation. The continual emission of radiation causes a black hole to slowly decrease in mass and evaporate into thin air. Many scientists believe that if this idea is true it can possibly move us closer to understanding the origin of our universe and what is to come. The fact that black holes do not exist forever reveals the idea that in the distant future, scientist predict that, all black holes will evaporate after the universe reaches an age of 10^100th year. This event will strip the universe of its matter by spreading individual photons and subatomic particles so far apart that nothing new can ever be created, and in essence the universe will reach the end of time. In 1975, one year after his initial findings, Hawking published his first book entitled Large Scale Structure of Space Time. The principles behind these black holes in relation to the speed at which gravitational energy travels inside this vacuum helped Hawking to better understand the relative structure of space and time. This knowledge helped him to realize the possibility of traveling through time (as explained in the videos: Hawkings: Black Hole Time Travel and Hawking: Train Ride to the Future) where Hawking shows that by traveling a near light speed, we can travel into the future.

Further Research and Beliefs
Diagram showing how the universe expands derived from one major event known as the big bang theory
Diagram showing how the universe expands derived from one major event known as the big bang theory

Hawking was genius in the fact that he didn't need to look at how other people solved problems, instead once he knew through his own rationality that something could be done he had an endless drive to uncover a solution. This led to his deepest research into the future of quantum cosmology, on the basis of the M-Theory which is an extension of the string theory that,"attempts to provide a complete, unified, and consistent description of the fundamental structure of our universe" (4) . In this manner these ideas provide a major component into the development of the Theory of Everything (TOE) which attempts to mend quantum mechanics with Einstein's theory of general relativity. Keeping these developing theories in mind, Hawking noted that, "recent observations tell us the present state of the universe, and we can run the equations backward to calculate what the universe was like at earlier times. But all that tells us is that the universe is as it is now because it was as it was then.To go further and be a real science, cosmology would have to predict how the universe should be" (5).

In order to make and test these predictions, Hawking realized that the universe must have a beginning under three conditions; only if Einstein's theory of general relativity was true, the energy density of the universe is positive, and the universe contains the amount of matter that we observe. Based on this, Hawking went on to say that, "if general relativity were correct the universe would have begun with a singularity" (6). This idea of gravitational singularity has helped Hawking to develop a model where the universe had no boundary in space-time thus making it infinite. This no-boundary proposal is consistent with how scientists form Big Bang models behind the development of the universe, under the idea that matter has always existed in space.

This underlying research has led Hawking to believe, that if scientists do arrive at a complete theory, "It would be the ultimate triumph of human reason – for then we should know the mind of God" (7). In his bestseller A Brief History of Time (1988), Hawking suggested that it was unnecessary to look to God the for the answers behind the origin of our universe, instead he feels these truths will be uncovered through future scientific research. As many take this as an atheist point of view, Hawking is not out to discredit the idea of a God as he believes that if such a God exists and furthermore governs the laws of the universe then he must not intervene with these natural laws and processes. In his work, The Grand Design(2010) Hawking writes, "The question is: is the way the universe began chosen by God for reasons we can't understand, or was it determined by a law of science? I believe the second." He adds, "Because there is a law such as gravity, the Universe can and will create itself from nothing" (8).

Life Accomplishments and Achievements

Works Cited Page