RE: [asa] The cat strikes again!

This cat truly has nine lives. The cat is either 100% alive or 100%
deceased, whether we are aware or not makes no difference to the cat
(unless we stop feeding him).

Let me pose another thought experiment.

You have just learned your house was built over a buried pirate
treasure. The cost in terms of damage to your property to try and dig
it up is roughly equal to the value of the treasure. Is your property
worth more because it is sitting on buried treasure or is it worth the
same?

Dick Fischer

Dick Fischer, Genesis Proclaimed Association

Finding Harmony in Bible, Science, and History

 <http://www.genesisproclaimed.org/> www.genesisproclaimed.org

-----Original Message-----
From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of George Murphy
Sent: Wednesday, November 28, 2007 8:34 AM
To: j burg; asa@calvin.edu
Subject: Re: [asa] The cat strikes again!

The editor says at the start, "this report apparently assumes that
humans are alone in the universe" but doesn't comment further on that.
It does deserve further reflection. The validity of Krauss & Dent's
argument does at least require that no other intelligent species in the
universe has developed to the point of being able to make the
astronomical observations we've made in the past 20 years.

& there's another point: Speaking of "observing dark energy" is a bit
problematic. We've observed accelerating expansion of galaxies & have
explained that in terms of the gravitational effect of dark energy. But
is dark energy in fact the explanation for cosmic acceleration? In the
double slit experiment, we could in principle determine which slit a
photon has gone through by looking for its gravitational influence
because we know that there is EM energy somewhere in the system & that
(at least if general relativity is right) that such energy has a
gravitational effect, so we could reasonably infer the position of a
photon from observations of the motion of a test particle. But we don't
know enough about what causes cosmic acceleration to be able to make
such inferences with complete confidence in that case.

Shalom
George
http://web.raex.com/~gmurphy/

----- Original Message -----

From: j burg <mailto:hossradbourne@gmail.com>

To: asa@calvin.edu

Sent: Tuesday, November 27, 2007 5:05 PM

Subject: [asa] The cat strikes again!

Some things about physics are too crazy not to be true. This one tops
them all.

Burgy

ROGER HIGHFIELD, Science Editor - Telegraph (U.K.)

A kind of cosmic variant of the Observer Effect. The odd thing, to me at
least, is that this report apparently assumes that humans are alone in
the universe.

Forget about the threat that mankind poses to the Earth: our activities
may be shortening the life of the universe too.

The startling claim is made by a pair of American cosmologists
investigating the consequences for the cosmos of quantum theory, the
most successful theory we have. Over the past few years, cosmologists
have taken this powerful theory of what happens at the level of
subatomic particles and tried to extend it to understand the universe,
since it began in the subatomic realm during the Big Bang.

The Boomerang Nebula, mankind 'shortening the universe's life'
Cosmologists claim by observing dark energy the universe has been nudged
closer to its death

But there is an odd feature of the theory that philosophers and
scientists still argue about. In a nutshell, the theory suggests that we
change things simply by looking at them and theorists have puzzled over
the implications for years.

They often illustrate their concerns about what the theory means with
mind-boggling experiments, notably Schrodinger's cat in which, thanks to
a fancy experimental set up, the moggy is both alive and dead until
someone decides to look, when it either carries on living, or dies. That
is, by one interpretation (by another, the universe splits into two, one
with a live cat and one with a dead one.)

New Scientist reports a worrying new variant as the cosmologists claim
that astronomers may have accidentally nudged the universe closer to its
death by observing dark energy, a mysterious anti gravity force which is
thought to be speeding up the expansion of the cosmos.

The damaging allegations are made by Profs Lawrence Krauss of Case
Western Reserve University in Cleveland, Ohio, and James Dent of
Vanderbilt University, Nashville, who suggest that by making this
observation in 1998 we may have caused the cosmos to revert to an
earlier state when it was more likely to end. "Incredible as it seems,
our detection of the dark energy may have reduced the life-expectancy of
the universe," Prof Krauss tells New Scientist.

The team came to this depressing conclusion by calculating how the
energy state of our universe - a kind of summation of all its particles
and all their energies - has evolved since the big bang of creation 13.7
billion years ago.

Some mathematical theories suggest that, in the very beginning, there
was a void that possessed energy but was devoid of substance. Then the
void changed, converting energy into the hot matter of the big bang. But
the team suggests that the void did not convert as much energy to matter
as it could, retaining some, in the form of what we now call dark
energy, which now accelerates the expansion of the cosmos.

Like the decay of a radioactive atom, such shifts in energy state happen
at random and it is possible that this could trigger a new big bang. The
good news is that theory suggests that the universe should remain in its
current state.
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But the bad is that quantum theory says that whenever we observe or
measure something, we could stop it decaying due what is what is called
the "quantum Zeno effect," which suggests that if an "observer" makes
repeated, quick observations of a microscopic object undergoing change,
the object can stop changing - just as a watched kettle never boils.

In this case however, it turns out that quantum mechanics implies that
if an unstable system has survived for far longer than the average such
system should, then the probability that it will continue to survive
decreases more slowly than it otherwise would. By resetting the clock,
the survival probability would now once again fall exponentially.

"The intriguing question is this," Prof Krauss told the Telegraph. "If
we attempt to apply quantum mechanics to the universe as a whole, and if
our present state is unstable, then what sets the clock that governs
decay? Once we determine our current state by observations, have we
reset the clock? If so, as incredible as it may seem, our detection of
dark energy may have reduced the life expectancy of our universe."

Prof Krauss says that the measurement of the light from supernovae in
1998, which provided evidence of dark energy, may have reset the decay
of the void to zero - back to a point when the likelihood of its
surviving was falling rapidly. "In short, we may have snatched away the
possibility of long-term survival for our universe and made it more
likely it will decay," says Prof Krauss. Not all agree, since his
interpretation hinges on one of the issues at the heart of quantum
theory - do you need people to do the observing?

This is not the only damage to the heavens that astronomers may have
caused. Our cosmos is now significantly lighter than scientists had
thought after an analysis of the amount of light given out by galaxies
concluded that some shone from lightweight electrons, not heavyweight
atoms. In all, the new analysis suggests that the universe has lost
about one fifth of its overall mass.

The discovery was made while trying to analyze clusters of galaxies -
the largest cosmological structures in the universe - and is not the
result of a cosmological diet but a major rethink of how to interpret
x-rays produced by the clusters.

Five years ago, a team at the University of Alabama in Huntsville lead
by Prof Richard Lieu reported finding large amounts of extra "soft"
(relatively low-energy) x-rays coming from the vast space in the middle
of galaxy clusters. Although the atoms that emitted them were thought to
be spread thinly through space (less than one atom per cubit metre),
they would have filled billions of billions of cubic light years.

Their cumulative mass was thought to account for as much as ten percent
of the mass and gravity needed to hold together galaxies, galaxy
clusters and perhaps the universe itself.

But now the team has taken a closer look at data gathered by several
satellite instruments, including the Chandra X-ray Observatory and have
had a major rethink about these soft X-rays, the bottom line being that
this chunk of the universe should now be discounted.

The reason is that the soft x-rays thought to come from intergalactic
clouds of atomic gas probably emanated from lightweight electrons
instead.

If the source of so much x-ray energy is tiny electrons instead of hefty
atoms, it is says the team as if billions of lights thought to come from
billions of aircraft carriers were found instead to come from billions
of extremely bright fireflies.

"This means the mass of these x-ray emitting clouds is much less than we
initially thought it was," said Dr. Max Bonamente. Instead, they are
produced by electrons travelling almost the speed of light (and
therefore "relativistic").

The discovery may also change what we think is the mix of elements in
the universe because these soft x rays mask the tell tale x ray
emissions of iron and other metals. "This is also telling us there is
fractionally more iron and other metals than we previously thought,"
said Bonamente. "Less mass but more metals."

Results of this research by Bonamente, Jukka Nevalainen of Finland's
Helsinki Observatory and Prof Lieu have been published in the
Astrophysical Journal.

The calculated mass of the universe ranges anywhere from 10 to the power
of 53 kg to 10 to the power of 60 kg and is complicated by the fact that
there is invisible matter we cannot see, called dark matter.

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Received on Wed Nov 28 13:58:02 2007