Author 193954

Stephen
Hawking
1942

English Theoretical Physicist, Cosmologist, Author, Honorary Fellow of the Royal Society of Arts, Awarded the Presidential Medal of Freedom, the highest civilian award in the United States, Lucasian Professor of Mathematics at the University of Cambridge, Research Chair at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario

Author Quotes

Because gravity shapes space and time, it allows space time to be locally stable but globally unstable. On the scale of the entire universe, the positive energy of the matter can be balanced by the negative gravitational energy, and so there is no restriction on the creation of whole universes. Because there is a law like gravity, the universe can and will create itself from nothing.

In fact, if general relativity were not taken into account in GPS satellite navigation systems, errors in global positions would accumulate at a rate of about ten kilometers each day!

So look carefully at the map of the microwave sky. It is the blueprint for all the structure in the universe. We are the product of quantum fluctuations in the very early universe. If one were religious, one could say that God really does play dice.

We create models in science, but also in everyday life. Model-dependent realism applies not only to scientific models, and mental models that we create all know, conscious or subconscious level, to interpret and understand the world every day. We cannot eliminate observer - ourselves - from our perception of the world, obtained by processing sensory perception and the way we think and rational. Our perception - and hence the observations which underpins our theories - not directly, but is adjusted by a kind of lens, interpretive structure of the human brain.

Bodies such as stars or black holes cannot just appear out of nothing. But a whole universe can.

In modern science laws of nature are usually phrased in mathematics. They can be either exact or approximate, but they must have been observed to hold without exception?if not universally, then at least under a stipulated set of conditions. For

Some people make a great mystery of this idea, sometimes called the multiverse concept, but these are just different expressions of the Feynman sum over histories.

Why is there something rather than nothing? Why do we exist? Why this particular set of laws and not some other? This is the Ultimate Question of Life, the Universe and Everything. We shall attempt to answer it in this book. Unlike the answer given in The Hitchhiker?s Guide to the Galaxy, ours won?t be simply ?42?.

Both observer and observed are parts of the world that has an objective existence, and any distinction between them has no meaningful significance. In other words, if you see a herd of zebras fighting for a spot in the parking garage, it is because there really is a herd of zebras fighting for a spot in the parking garage.

In physics a system is said to have a symmetry if its properties are unaffected by a certain transformation such as rotating it in space or taking its mirror image. For example, if you flip a donut over, it looks exactly the same (unless it has a chocolate topping, in which case it is better just to eat it).

That multiverse idea is not a notion invented to account for the miracle of fine-tuning. It is a consequence of the no-boundary condition as well as many other theories of modern cosmology. But if it is true, then the strong anthropic principle can be considered effectively equivalent to the weak one, putting the fine-tunings of physical law on the same footing as the environmental factors, for it means that our cosmic habitat?now the entire observable universe?is only one of many, just as our solar system is one of many. That means that in the same way that the environmental coincidences of our solar system were rendered unremarkable by the realization that billions of such systems exist, the fine-tunings in the laws of nature can be explained by the existence of multiple universes.

But humans are a curious species. We wonder, we seek answers. Living in this vast world that is by turns kind and cruel, and gazing at the immense heavens above, people have always asked a multitude of questions: How can we understand the world in which we find ourselves? How does the universe behave? What is the nature of reality? Where did all this come from? Did the universe need a creator?

In the early universe?when the universe was small enough to be governed by both general relativity and quantum theory?there were effectively four dimensions of space and none of time. That means that when we speak of the beginning of the universe, we are skirting the subtle issue that as we look backward toward the very early universe, time as we know it does not exist! We must accept that our usual ideas of space and time do not apply to the very early universe. That is beyond our experience, but not beyond our imagination, or our mathematics.

The Greeks? Christian successors rejected the idea that the universe is governed by indifferent natural law. They also rejected the idea that humans do not hold a privileged place within that universe. And though the medieval period had no single coherent philosophical system, a common theme was that the universe is God?s dollhouse, and religion a far worthier study than the phenomena of nature. Indeed, in 1277 Bishop Tempier of Paris, acting on the instructions of Pope John XXI, published a list of 219 errors or heresies that were to be condemned. Among the heresies was the idea that nature follows laws, because this conflicts with God?s omnipotence. Interestingly, Pope John was killed by the effects of the law of gravity a few months later when the roof of his palace fell in on him.

calculations show that a change of as little as 0.5 percent in the strength of the strong nuclear force, or 4 percent in the electric force, would destroy either nearly all carbon or all oxygen in every star, and hence the possibility of life as we know it. Change those rules of our universe just a bit, and the conditions for our existence disappear!

In the Game of Life, as in our world, self-reproducing patterns are complex objects. One estimate, based on the earlier work of mathematician John von Neumann, places the minimum size of a self-replicating pattern in the Game of Life at ten trillion squares?roughly the number of molecules in a single human cell.

The Ionian idea that the universe is not human-centered was a milestone

Consider the apparent dimension of the universe. According to M-theory, space-time has ten space dimensions and one time dimension. The idea is that seven of the space dimensions are curled up so small that we don?t notice them, leaving us with the illusion that all that exist are the three remaining large dimensions we are familiar with.

It is hard to imagine how free will can operate if our behavior is determined by physical law, so it seems that we are no more than biological machines and that free will is just an illusion.

The laws of M-theory therefore allow for different universes with different apparent laws, depending on how the internal space is curled. M-theory has solutions that allow for many different internal spaces, perhaps as many as 10500, which means it allows for 10500 different universes, each with its own laws. To get an idea how many that is, think about this: If some being could analyze the laws predicted for each of those universes in just one millisecond and had started working on it at the big bang, at present that being would have studied just 1020 of them. And that?s without coffee breaks.

Descartes, for instance, in order to preserve the idea of free will, asserted that the human mind was something different from the physical world and did not follow its laws. In his view a person consists of two ingredients, a body and a soul. Bodies are nothing but ordinary machines, but the soul is not subject to scientific law.

La capacidad humana para sentirse culpable es tal que siempre podemos hallar maneras de acusarnos a nosotros mismos.

The most incomprehensible thing about the universe is that it is comprehensible. ?ALBERT EINSTEIN

Do we really have reason to believe that an objective reality exists?

Many people throughout the centuries has attributed to God the beauty and complexity of nature that, in his time, seemed to have no scientific explanation. But as Darwin and Wallace explained how the apparently miraculous design of living forms could appear without the intervention of a Supreme Being, the concept of the multiverse may explain the fine tuning of the physical laws without a benevolent Creator who made the universe our advantage.

Author Picture
First Name
Stephen
Last Name
Hawking
Birth Date
1942
Bio

English Theoretical Physicist, Cosmologist, Author, Honorary Fellow of the Royal Society of Arts, Awarded the Presidential Medal of Freedom, the highest civilian award in the United States, Lucasian Professor of Mathematics at the University of Cambridge, Research Chair at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario