Re: so, is it really true that observing dark energy hastens the end of the Universe?

In article
<38f2eccb-f0c0-468f-9e36-4c698a2494d7@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
robert bristow-johnson <rbj@xxxxxxxxxxxxxxxxxxxx> writes:

first there was that weird Swiss ballot encryption thing:
http://www.smh.com.au/news/World/Swiss-to-use-encryption-voting-method/2007/10/13/1191696216022.html

No mystery here.

this really seems like crap. in the former, i cannot understand how a
robust communications system cannot tolerate the loss of a photon, and
if it can, how it can differentiate a loss of a photon because of a
kink in the fiber-optics vs. someone observing the data.

It can't. To quote from the article "Those that are lost - or
intercepted - become useless, Gisin said." It doesn't matter. The
point is that no-one can intercept the data, because the coherence is
then destroyed. That doesn't mean that there are no other ways to
destroy the coherence.

now there is this weirder astronomers are hastening the end of the
universe thing:
http://www.theage.com.au/news/world/bscienceb-did-astronomers-hasten-end-of-the-universe/2007/11/22/1195321929950.html

"Incredible as it seems, our detection of the dark energy may
have reduced the life-expectancy of the Universe," says
Lawrence Krauss of Case Western Reserve University.

in the
latter, the light from the distant galaxies has been emitted, some of
it absorbed by dark matter, eventually an obscenely small portion
arrives on this planet where an obscenely large portion is just
absorbed. what difference to the Universe should it make as to what
state the neurons in the brains of some astronomers and physicists
are? this is silly.

I'll have to read the original article. On the one hand, Krauss is
certainly not a crackpot and has been investigating the cosmological
constant for a long time, usually contributing something interesting.
On the other hand, the account might be garbled somewhat, although that
seems unlikely if the quote is correct.

Things like this are what inspired Einstein to ask whether the moon is
really only there when he looks at it.

It's all down to the interpretation of quantum mechanics. Many people
actually do believe that consciousness plays a real role in quantum
mechanics. (Interestingly, Penrose a) believes that quantum mechanics
plays a real role in consciousness and b) his "interpretation" is not
really an interpretation since it is in principle possible to
differentiate it from other interpretations by experiments.) My own
view is that the universe existed before we (or any other consciousness
did) and that its evolution is more or less independent of whether we
came into existence or not.

Let's look at the article in more detail:

Until recently, a common idea was that the energy unleashed in the Big
Bang happened when a "false vacuum" - a bubble of high energy with
repulsive gravity - broke down into a safe, zero-energy "ordinary"
vacuum.

I'm not sure what is meant by "common". Although many people hold this
view, it is important to realise that it is not essential for the
general picture of the big bang, the expansion of the universe, the
acceleration of the universe etc.

For one thing, cosmologists have discovered that the Universe is still
expanding.

No surprise here. What is probably meant is "still accelerating".

Dark energy, goes the thinking, is a result of the Big Bang and is
accelerating the Universe's expansion.

Well, what is NOT a result of the big bang?

If so, the Universe is not in a nice, stable zero-vacuum state but
simply another "false vacuum" state that may abruptly decay again -
and with cataclysmic consequences.

Non-sequitur. If the "dark energy" is a classical cosmological
constant (and there is NO evidence to indicate that it is not, despite
the fact that some folks have checked whether observations are more
compatible with something else), then there is no danger of "decay".

The bad news is: the quantum effect, a truly weird aspect of physics
that says whenever we observe or measure something, we reset its
clock.

I'll have to read the original article to see what is really meant by
this statement.

Krauss and colleague James Dent point to measurements of light from
supernovae in 1998 that provided the first evidence of dark energy.

These measurements may have reset the decay clock of the "false
vacuum" back to zero, back before the switching point and to a time
when the risk of catastrophic decay was greater than now, say Dent and
Krauss.

"Incredible as it seems, our detection of the dark energy may have
reduced the life-expectancy of the Universe," says Krauss.

"We may have snatched away the possibility of long-term survival for
our Universe and made it more likely it will decay."

I agree with you that this is simply absurd. Even assuming the effect
does exist, perhaps some other intelligence has already observed the
expansion. In that case, our observation will make no difference, since
if "The energy shift from the decay would destroy everything in the
Universe, `wiping the slate clean'", then it will wipe it clean for them
AND us.

.

Relevant Pages

  • Re: Dont like the truth? Lie.
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  • Re: http://sciencenow.sciencemag.org/cgi/content/full/2008/801/3
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    (sci.physics)
  • String theorist explores dark energy and our unique pocket of the universe (Forwarded)
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  • The puzzle of dark energy
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  • Finding a Way to Test for Dark Energy (Forwarded)
    ... In a paper to be published in Physical Review Letters, physicists Eric Linder of Berkeley Lab and Robert Caldwell of Dartmouth show that physics models of dark energy can be separated into distinct scenarios, which could be used to rule out Einstein's cosmological constant and explain the nature of dark energy. ... In their paper in Physical Review Letters Linder and Caldwell describe two scenarios, one they call "thawing" and one they call "freezing," which point toward distinctly different fates for our permanently expanding universe. ... Under the thawing scenario, the acceleration of the expansion will gradually decrease and eventually come to a stop, like a car when the driver eases up on the gas pedal. ...
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