Posted on 09/09/2001 1:05:44 PM PDT by telos
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.
Okay. Big units for big thinkers....
Disclaimer: the above is not intended as Adult Humor
So far, I have: footnote: Schrodinger's Cat was a logical paradox postulated by Physicicist Irwin Schrodinger in which the question of whether a cat in a bax was dead or alive depended on whether anyone looked in the box.
Ah, I see the problem.
You forgot to read the warning in the Instructions for the Guth TURBO Space Inflator™, where it says:
"WARNING: the Guth TURBO Space Inflator™ cannot be used to selectively inflate on a limited volume of space. Use ONLY if you wish to inflate the ENTIRE fabric of the Universe. Warranty void if used for unintended purposes."
Thus, when you hit the "Inflate" button, not only are points A and B displaced, but so is C, (and every other point in the Universe, for that matter.) It cannot be used for specific directional travel "inside" the Universe, like some sort of FTL Star Trek transporter.
The useful analogy here is our old friend, the surface of a balloon. The surface is a 2-D analog of our 3-D space. Inflation is represented by a very rapid increase in pressure inside our imaginary balloon (imagine a Cosmic Linda Lovelace is pressed into service, if that aids the thought experiment), causing the surface to expand EVERYWHERE very rapidly, such that the change in distance between points not very close to each other appears to occur FTL. But within the 2-D surface of the balloon, the points are all fixed with respect to each other, they acquire no momentum from the Inflation. Once the Inflation stops, all the points on the balloon's surface are in the same relation to each other as they where before the inflation, except that they are all proportionately further apart than they were. The ballon's surface is just bigger; it's shape, and the relationship of the points on the surface, remain unchanged, except for distance. No points on the surface have been mapped into some other points, with angry wrinkling and tearing of the balloon's surface. Just uniform expansion, everywhere.....
Unless I'm missing something..... ;-)
Your original statement (reply # 69) was:
But since all things in a closed system tend toward entropy, that includes light.
Thus, you have argued that entropy, by which I presume you mean the Second Law of Thermodynamics, requires the speed of light to "deteriorate."
Light is an electromagnetic phenomonon, not a Thermodynamic one. The fact that the closed thermodynamic systems tend to undergo changes that result in an increase in the overall entropy of the system and its environment has nothing to do with electromagnetism, and hence light.
Thus, you have provided an erroneous justification for the putative deterioration in the speed of light.
Let me be clear: I am not restating what you stated; I am repudiating it.
Admittedly, the last really heavy physics I took at a graduate level was quantum mechanics. And that was mostly just out of curiousity, and, to a certain extant, I was mildly intersted at the time in its applications to solid state electronics. Actually, the ironic thing is that I ended up studying mostly digital communications and signal processing and you might not believe how often Heisenber-like relationships show up in things there, for instance, the Discrete Fourier Transform. My professional life as a software engineer has taken too much time to have much more than an arm-chair physicist's understanging of most of these subjects, although it is often much more interesting. The last intersting physics 'books' I read were Schrodinger's Kittens and Feynman's QED, neither of which are technically challenging. To really understand these kinds of things in depth requires a little more than after-dinner reading!!
It just struck me as odd at the time that these guys, serious physicists like yourself, I believe, readily admitted that they had no idea how or why the red shift actually occurred. I'm more than willing to accept it as a property of light travelling through space-time, and they could have been wrong, or my memory of it could be wrong, but I've always kept it in the back of my mind...
With that warning label, I certify that your product is safe for use by responsible adults within the universe. (But nowhere else!)
But we have a very accurate measurement of what the speed of light was 150,000 years ago. We can see the expanding "ring" of the blast from supernova 1987a, and measure the speed of light that way. If the speed of light were faster back then, the circle it makes would be bigger on the face of the sky. It is exactly the size we expect it to be. How do you account for that?
Not quite. The cat exists in a superposition of both dead and living states. It is not until the box is opened and someone(?something?) makes an observation of the cat that Shrodinger's wave equation collapses and one or the other state is realized. With all this FTL talk going on, it might be appropriate to introduce Shrodinger's Kittens or the EPR thought experiment ...
Ha, speaking of EPR, I don't know whether Lawyers care about non-locality, but I'd bet a dime to a dozen that they don't believe in reality.
In a sentence or two, what legal issue does this footnote pertain to?
Here's how I, a particle physicist, would check the relationship E=mc². I would first measure the mass of the electron very accurately. I would then create positronium, which is a bound state of an electron and a positron. I would then allow it to decay into two photons, and measure the energy of the photons with an electromagnetic shower counter.
Of course, there's no way I could measure the energy of any single photon to a sufficient accuracy, so I would measure a large number of them and do a statistical fit. There will be a radiative tail (caused by the emission of softer photons that escape detection) so I will have to correct for that, too. There will be detector effects that I will have to correct for. But at the end of the day, if I understand my apparatus, I can make the measurement to any desired statistical accuracy, given enough data.
A nuclear physicist might approach the problem differently, by making a careful measurement of isotopic abundances in a sample (for example, with x-ray fluorescence), allowing the sample to decay for awhile (making careful measurements of alpha or neutron emission counts and energies throughout) and then making another careful measurement of isotopic abundances. Very accurate measurements of nuclear masses are available, so that should be all that is needed for the experiment. Again, while it isn't possible to measure any given nuclear decay with any accuracy, statistics will win out in the end. You can achieve almost any accuracy (right down to the limit of your systematic errors) if you run the experiment long enough.
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.
Golly! Somewhere there's an improbable universe where Ronald Regan became president and the Soviet Union collapsed. That would be nice.
Ah, Everett's "many worlds" interpretation. Perhaps you can answer a question I have: how are relative weights accounted for in this interpretation? I mean, suppose I have two possible outcomes, but one is 100 times more likely than the other. In the Everett interpretation, each of the two worlds (representing the two outcomes) is just as "real" as the other, so how do we account for the fact that "our" world overwhelmingly picks what we compute to be the more likely outcomes? How do they make sense of reality in the (equally real) worlds where the low probability outcomes usually prevail?
It might be tempting to solve the problem by creating many more worlds still: 100 new worlds where the likely outcome prevails, and one new world where the unlikely outcome prevails. Why, not? In for a penny, in for a pound. Unfortunately, that can't save my bacon: I can easily create a quantum state where the eigenstates have a relative weight of the square root of two, which is irrational. Now what?
Another problem, which has always been a stumbling block for me, is the source of all these new universes. Every second, billions of universes are being created. (Do I stop for gas or don't I? Do I make that phone call or don't I?) Aside from the problem or the origin of all this stuff, where does it all get positioned? If it exists, it's part of our universe. If it's another universe entirely, where is it? And why does the activity of humans have this amazing creative power?
It doesn't. Human decisions are easy to visualize and convenient to state for the sake of argument, but they are chicken feed compared to the 20 or so orders of magnitude of quantum transitions that occur in every gram of matter every fraction of a second. Each one of those creates worlds, too, in this interpretation.
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