On Sat, 09 Feb 2002 01:56:15 +0100 Scott MARTENS <sm at kiera.com> writes:
> Which universal constant did Einstein give up on, and at the behest
> of
> which Vatican physicist?
I believe that Hakki was referring to the cosmological constant. When Einstein first attempted to apply his general theory of relativity to the universe as a whole, he found that the most obvious solutions to his field equations implied that the universe must either be expanding or shrinking, but Einstein assumed, like most scientists at that time that the universe was unchanging from a macro point of view. Therefore, to get around having to accept solutions to his equations, which implied an expanding or contracting) universe, which seemed to be unphysical, Einstein added on to his field equation in additional term, involving what he characterized as the cosmological constant, which counteract any deviations from a static universe. A few years later, the astronomer Edward Hubble, determined on the basis of observed red-shifting of light from distant nebulae, that we lived in an expanding universe. Einstein became convinced on this basis that he had been in error, so he dropped the term with the cosmological constant from his equations. And that is where the matter stood for about sixty years or so, until the 1980s, when Guth proposed his inflation hypothesis to resolve some unsolved problems in cosmology. In Guth's theory, it was proposed that during the universe's first nanosecond of existence, following the Big Bang, that the collapsing cosmological Higgs field, would for a fraction of a nanosecond or so, lead to a large cosmological constant, during which the inflation of the universe would have occured. After, that the magnitude of the cosmological constant would drop down to zero (or close thereabouts).
By the late 1980s, early 1990s, cosmologists began to be troubled, by contradictions between calculations of the ages of the oldest stars, which indicated that the very oldest stars were older that the universe itself, as estimated, using the equations of the Big Bang theory. Some cosmologists, suggested that this contradiction could be resolved if it was posited that instead of the cosmological constant dropping off to zero, following cosmic inflation, but rather dropped down to a relatively small but finite, non-zero value. Such a modification of the existing cosmological theory, would result in the universe's computed age being greater, than had previously been estimated, thereby resolving the contradiction with the calculations concerning the ages of the oldest observed stars.
Jim F.
>The Big Bang wasn't current until after
> Einstein's death, and wasn't universally accepted until the late
> 70's at
> least.
>
> Scott Martens
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