courtesy http://starchild.gsfc.nasa.gov/docs/StarChild/whos_who_level2/hawking.html
courtesy http://starchild.gsfc.nasa.gov/docs/StarChild/whos_who_level2/hawking.html
Steven Hawking 1942 - 2018
Another physicist who has pushed the envelope was Dr. Steven Hawking who once held Isaac Newton's chair as the Lucasian Professor of Mathematics at Cambridge University in England. Just as Einstein "tweaked" Newtonian mechanics to cover situations where objects move extremely fast, Hawking "tweaked" the laws to cover situations where the universe is extremely dense. Having been diagnosed with ALS (Lou Gehrig’s Disease) as a student, Hawking was forced into a profession which emphasizes the mind and not the body - theoretical physics. There he excelled to the point where he is now considered an intellectual equal to Newton and Einstein.
Hawking's graduate work was in the field of black holes. A black hole occurs when a huge quantity of ordinary matter is compressed into an incredibly small volume ... actually no volume (if that makes any sense). Under these conditions, the gravitational field is so strong (space is so curved) that light directed out of this object would be bent right back into it. This would make it invisible to us, hence the name "black hole". Hawking has shown that there are conditions (far enough away from the actual black hole) where the universe would produce radiation which is detectable. This radiation has since been called "Hawking Radiation".
Hawking's understanding of the universe under these extreme conditions led him into a different direction - cosmology, which deals with the evolution of the universe. The concept that the universe started with a "Big Bang" will be covered in a different section of this project. However, the behavior of the universe near the very beginning of time was not much different from the conditions you find at a black hole. Understanding the way the laws of physics behave under these conditions is imperative if you wish to answer questions like:
What was the universe like in the very beginning?
How did the universe begin?
Do you need a God to make a universe? (Wow ... isn't that a question that
blows your mind?)
Is it even possible for physics to answer these questions?
What ideas will come out of this great mind is still not finished. In fact, the end result may not come from one individual, because the scope of the problem has baffled all who attempted to tackle the problem. Even Einstein failed after over 40 years of effort.
The problem here lies with the known laws of physics and the behavior of matter under these extreme conditions. On one hand, you have a fairly good understanding of gravity. This is important because both black holes and universes have a lot of mass. On the other hand, we have conditions which deal with the nature of matter on very small scales (which involve some of the other forces of nature which are discussed below). The known laws of physics do not agree with each other under these conditions. That is, gravity tells us one thing, and quantum mechanics (physics of the very small) say something else. The solution? We need a better understanding of the laws of physics.
Cosmologists who are currently pushing our level of understanding about the universe are like master carpenters. They both develop ideas and craft models which require incredible skill and patience as well as an acute eye to detail. The master carpenter relies on precision tools to carry out the project, and so does the cosmologist. The difference is, the carpenter's tools are quality drills, lathes, chisels, etc. ... and the cosmologists use the known laws of physics. It, therefore, becomes incredibly important to develop a good understanding of these natural laws and how they apply under all conditions.
We have spent a lot of time describing just one law of the universe- gravity. However, it is not the only known force found in nature. Everyone is familiar with two other forces, magnetism as well as electric forces (plus electric charge given to protons and negative electric charge given to electrons). In 1864, James Clerk Maxwell demonstrated that these two separate forces could be described and understood with one set of equations and bonded them together as electro-magnetic interactions. This was the first time two forces in nature which were once thought as separate, could be merged into one model.
Other forces in nature were later found after studying the nature of the atomic nucleus. These forces were known as the strong nuclear force (which holds the nucleus of an atom together) and weak nuclear force (which helps explain radioactive decay). In the past few years, astronomers have discovered a new force in nature known as Dark Energy (more on this one later).
Einstein realized the importance of finding a model which could be used to incorporate all the known laws of physics into a Grand Unified Theory (GUTS) or the "Theory of Everything". Remember the KISS model - Keep It Simple, Stupid! The quest for a unified model has become the "holy grail" in physics. It became clear that any attempt to merge the laws (known at that time) had to incorporate a branch of mathematics known as quantum mechanics, which dealt with interactions at the atomic level. Einstein struggled with this (personally) because part of quantum mechanics deals with probability, and he was often quoted saying, "God does not throw dice". Einstein was unsuccessful, but others have made considerable progress in that direction.
In the period from 1961-1967, three physicists - Glashow, Weinberg, and Salam were awarded the Nobel Prize for finding a model which merged the electromagnetic force with the weak nuclear force. This was known as the electroweak model.
Perhaps the quest for a unifying theory is at hand. The biggest problem is merging the world of the very small (quantum mechanics) with the world of the very big (gravity). In that attempt, a new model has emerged - String Theory or M Theory. Basically it says that all matter in this universe can be described as tiny "wiggles" in energy strings. The nature of the wiggle determines the type of matter you get. The good news is that this model does a nice job of merging the concepts of gravity (big scale interactions) with quantum mechanics (small scale interactions). No other model has been able to do this successfully. There are hundreds of physicists currently working on the model and the book is not yet finished. This model makes some pretty bizarre predictions about the way this universe is put together. Can you imagine that reality actually may consist of 11 separate dimensions? I can't ... 3 dimensions are all my brain can handle (maybe 4 if you include time). However, this model makes some incredible predictions how a universe can "pop" into existence. Stay tuned ...
Finally, we need to point out a few individuals who are at the "cutting edge" of research in string theory:
Juan Maldacena Brian Greene Sheldon Cooper (Ok, maybe not)
Personal note: I have a hard time with string theory. The reason is there has not been one test (to date) that would suggest the model fits the universe (that I'm aware of). Just because a model works well in explaining things does not mean the universe follows the model (a lesson learned from Ptolemy). Furthermore, string theory has predicted several "solutions" .... like 10500 solutions, suggesting that just about anything can happen. If that is the case, the best one can say is .... "Well, my theory describes our current observations" when, in fact, they could make that claim no matter what we observe. That is, the model can describe anything we observe. That doesn't sound like a good way to do science. However, I have no alternative suggestions and I certainly am NOT qualified academically to truly understand the mathematics involved. For now, I will be happy to let this idea play itself out and wait to see what this small group of Sheldon Coopers come up with. We certainly need something (in the way of a working theory) before we can tackle the even more fundamental questions.
©Jim Mihal 2004, 2014, 2019 - all rights reserved