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A GROUP of astronomers and cosmologists has warned that the laws thought to govern the universe, including Albert Einstein's theory of relativity, must be rewritten. The group, which includes Professor Stephen Hawking and Sir Martin Rees, the astronomer royal, say such laws may only work for our universe but not in others that are now also thought to exist. "It is becoming increasingly likely that the rules we had thought were fundamental through time and space are actually just bylaws for our bit of it," said Rees, whose new book, Our Cosmic Habitat, is published next month. "Creation is emerging as even stranger than we thought." Among the ideas facing revision is Einstein's belief that the speed of light must always be the same - 186,000 miles a second in a vacuum. There is growing evidence that light moved much faster during the early stages of our universe. Rees, Hawking and others are so concerned at the impact of such ideas that they recently organised a private conference in Cambridge for more than 30 leading cosmologists. Cosmology - the study of the origins and future of our universe - became popular in the early 20th century for physicists who wanted to think the unthinkable about creation. Einstein's theory of relativity, which describes how gravity controls the behaviour of our universe, was one of cosmology's greatest triumphs. But Einstein said there was an even deeper issue, which he described as whether God had any choice. In other words, could the laws that governed the way our universe formed after the big bang have worked any differently? He concluded that they could not. In the past 40 years, however, the increasing power of astronomical instruments has turned cosmology from a theoretical science into a practical one and forced scientists to re-examine Einstein's conclusions. Among the most striking claims is that our universe only exists because of a fine balance between several crucial factors. One is the rate at which nuclear fusion releases energy in stars such as the sun by squashing hydrogen atoms into helium and then other elements. Astronomers have found that exactly 0.7% of the mass of the hydrogen is converted into starlight and that if this figure had been just a fraction different then carbon and other elements essential to life could never have formed. Another puzzle is the so-called "smoothness" of our universe, by which astronomers mean the distribution of matter and radiation. In theory, the big bang could have produced a universe where all the matter clumped together into a few black holes, or another in which it was spread out evenly, forming nothing but a thin vapour. "It could be that the laws that govern our universe are unchangeable but it is a remarkable coincidence that these laws are also exactly what is needed to produce life," said Rees. "It seems too good to be true." What he, Hawking and others such as Neil Turok, professor of maths and physics at Cambridge, are now looking at is the idea that our universe is just one of an infinite number of universes, with different laws of nature operating in each. Some universes would have all their matter clumped together into a few huge black holes while others would be nothing more than a thin uniform freezing gas. However, Hawking and his colleagues increasingly disagree over how this "multiverse" could work. At the conference Hawking dismissed the idea of a series of big bangs on the grounds that it extended into the infinite past and so could never have a beginning. |
Now, it all depends on the meaning of: 'light', 'mile', 'second' and 'vacuum'. Doesn't it?
PH, I know that this isn't what you wanted to hear.
From Hawking's POV, it seems he feels both an temporally infinite Universe (or infinite repeating Universe) and a temporally infinite Deity suffer the same deficiency. Essentially, "it/he was always there" is just a philosophical sleight of hand to avoid the messy problem of origins.
This doesn't bode well for the turtles, either.
I now hear that it is 10 billion years old.
Wow, to think I have lived 8 billion years.
I wonder how old it will be by the time I kick the bucket.
That's a laughable notion. One would presume that Hawking has no problem with infinities in space, so why should his cosmology stumble over an infinity in time?
Or, to put it another way, our current cosmology (for this universe, at least...in itself a curious notion...) traces back to a singularity of infinitely dense, infinitely hot matter at time T=0. What makes this idea any less metaphysical than the idea of the existence of a time T=-1 femtoseconds?
For example, let's say that a guy named John Doe decides to sleep in and miss work at his job in San Francisco. An earthquake than hits and kills John in his sleep. John was later supposed to be responsible for finding the cure for cancer, which he cannot do because of his decision. According to TQR there is another universe in which he made the opposite decision, saving millions of lives. It is another possibility that the physical constants of the universe may vary in other universes, so I can see how this can be.