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Name: Tony L.
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 1/13/2003


Question:
In Stephen Hawkins "A Brief History Of Time" he talks about black holes and infinite gravity distorting space-time, and also discusses the "big bang" and "big crunch". Is it not possible that if gravity has such an effect on space-time, that the "big bang" and "big crunch" occupy the exact same point in space-time?


Replies:
When discussing the "Big Bang", which is a quantum mechanical / relativistic model, you need to be prepared to encounter non-intuitive concepts. This is not easy, because scientists almost always reason by analogy. A very simple example is the hydrogen atom. We talk about electron being in various "orbitals". This is an analogy to planets moving around the sun, hence the name"ORBITal". There are numerous other examples. For systems that are quantum mechanical / relativistic you must always keep in mind that intuitive analogies are not only incomplete, they will lead one into paradoxes and contradictions. An example where this occurs in Young's famous "double slit" experiment (See: "Schrdinger's Kittens" by Gribbin for a detailed discussion without the mathematical scaffolding. The only alternative is to let the mathematics lead us from premises to conclusions and predictions and test and compare them against / to experimental results and measurements.

I'm not a cosmologist, but in all the readings I have done on the "Big Bang" the intuitive question like , "Where did it happen?" or what was there "before" the "Big Bang" are meaningless. The "Big Bang" created space-time. It is a mathematical singularity -- like dividing by zero. In a sense it occurred everywhere at "the same time". A quote attributed to Richard Feynman puts things in perspective, "If anyone says they 'understand' quantum mechanics, they do not understand the problem!!!"

Experiments and predictions of theory have forced theoretical cosmologist to reconsider previously unthinkable assumptions -- like: Can things travel faster than the speed of light (inflation)? Was the speed of light (in a vacuum) ever different than it now is? Why does the electron have the mass, charge, and spin it has rather than some other value? The same question can be asked of all other "fundamental things". Do parallel Universes exist? Are time and space the only "dimensions" that govern the Universe? Is the force of gravity always attractive? If so, why? A "perfect vacuum" is full of all sorts of particle pairs (virtual particles) that are created and destroyed on a very short time scale so that (at present) they cannot be detected? Does an electron (or other Q.M. particle) have to be observed to exist? If so, what does "observed" mean? What comprises "observation"? How does the "uncertainty principle" fit into all of this?

In short, the closest answer to your question is, "Yes and No!!" Not very intuitive.

Vince Calder



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