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Before the year 1000, the word "she" did not exist in the English language. The singular female reference was the word "heo" which also was the plural of all genders. The word "she" appeared only in the 12th century, about 400 years after English began to take form. "She" probably derived from the Old English feminine "seo", the Viking word for feminine reference. |
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Mankind 'shortening the universe's life'
Posted on Tuesday, November 27, 2007 (CST) by Thoth
 Forget about the threat that mankind poses to the Earth: our very ability to study the heavens may have shortened the inferred lifetime of the cosmos. That does not mean the field of astronomy does direct harm. A universe with a truncated lifespan may come hand in hand with the ability of astronomers to make cosmological measurements, according to two American scientists who have studied the strange, subtle and cosmic implications of quantum mechanics, 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.
But there is an odd feature of the theory that philosophers and scientists still argue about. In a nutshell, the theory suggests that quantum systems can exist in many different physical configurations at the same time. By observing the system, however, we may pick out one single 'quantum state', and therefore force the system to change its configuration.
They often
illustrate their concerns about what the theory means in this respect
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.)
If we are part of the
system, however, things get a bit trickier. Our observations do not
change the system so much as help determine what state we find
ourselves a part of. This latter facet, related to treating the
universe as a quantum state, has puzzled theorists for some time.
New Scientist reports a
worrying new variant as the cosmologists claim that astronomers may
have provided evidence that the universe may ultimately decay 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
determined that the cosmos is in a state when it was more likely to
end. "Incredible as it seems, our detection of the dark energy may
provide evidence that the universe will ultimately decay," says Prof
Krauss.
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.
But the bad is that quantum
theory says that whenever we observe or measure something, we can
select out a specific quantum state from what otherwise would have been
a multitude of states, each of which could have been selected out with
varying probabilities.
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.
Thus, as a result of making
cosmological observations of dark energy, we may have confirmed that we
are in a state where the probability of its survival may 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 effectively determined that the
clock is not running at late times? If so, as incredible as it may
seem, our detection of dark energy may imply both an unstable universe
and a short life expectancy."
Prof Krauss says that the
measurement of the light from supernovae in 1998, which provided
evidence of dark energy, may imply that the likelihood of its surviving
is falling rapidly. "In short, cosmological observations may suggest
that the quantum state of our universe is such that the probability of
long-term survival is limited," says Prof Krauss.
And Prof Krauss stresses
that resetting the cosmic clock was not something we have done to the
universe but rather what our cosmologically observations may imply
about our knowledge of the cosmic clock: "I did not mean to imply
causality - namely that our measurement itself reduces the lifetime of
the universe - but rather that by being able to make our measurement we
may thus conclude that we may not be in the late decay stage."
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.
Copyright: Telegraph
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Re: Mankind 'shortening the universe's life'
by Rareheart on Tuesday, November 27, 2007 (CST)
(User Info | Send a Message) | The folly of this train of thought is based on leaving out one very important element in this equasion. Science has established a group of "forces" that is incomplete...we have overlooked one very important 'force'. The source of our Sun's energy...plasma...or the flow of "Quons".
We have not properly named this energy because greed will continue to block its 'understanding' until greed can be dispelled. ( I know that sounds 'out there'.)
Probably not gonna happen...right?
That kind of thinking will insure that it doesn't. |
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