When the huge subatomic-particle smasher under the
Swiss-French border starts running, it's supposed to reveal what
happened the instant after the big bang, the theoretical beginning of
our universe 13.7 billion years ago.
The Large Hadron Collider, which suffered a
temporary setback last week, might find some answers. But it will leave
other questions on many people's minds, such as what happened BEFORE
the big bang, and even whether there was a "before."
A scientific mini-industry has
popped up as deep-thinking physicists and cosmologists bat around
various guesses as to what may have happened in a "pre-big bang."
Some of the top minds in this field gathered at Columbia University earlier this month to debate these questions.
"What banged? Where did it come from?" was the question raised by
Laura Mersini-Houghton, a cosmologist at the University of North
Carolina at Chapel Hill.
"Is ours the only universe? If so, how did it come to exist?" asked
Paul Davies, a cosmologist and authority on science and religion at
Arizona State University in Tempe.
Respected scientists have proposed a flock of theories to describe
what might have happened before the birth of our familiar universe of
space and time.
The concepts have fanciful names such as "the big bounce," "the
multiverse," "the cyclic theory," "parallel worlds," even "soap
bubbles." Some propose the existence of multiple universes. Others hold
that there's one universe that recycles itself endlessly, rather as
Buddhists believe. Judeo-Christian theologians may have difficulty
accepting any of these notions.
Most of the hypotheses are variations on an older idea that the
universe has no beginning and no end, contrary to the big-bang theory,
which says that our universe originated at a specific point and will
end sometime in the distant future.
"Neither time nor the universe has a beginning or an end," two
leading cosmologists, Paul Steinhardt of Princeton University and Neil
Turok of Oxford University, wrote in their 2007 book, "Endless
Universe: Beyond the Big Bang."
"The evolution of the universe is cyclic, with big bangs occurring
once every trillion years or so, each one accompanied by the creation
of new matter and radiation that forms new galaxies, stars, planets and
presumably life," they wrote. "Ours is only the most recent cycle."
Some scientists contend that observational evidence may be found to
back up the speculation. They say that no scientific theory can be
considered valid until it's been tested.
"It is becoming increasingly clear that multiverse models grounded
in modern physics can be empirically testable," Max Tegmark, a
theoretical physicist at the University of Pennsylvania, Philadelphia,
wrote in "Parallel Universes," a chapter in the 2003 book "Science and
Ultimate Reality."
Some researchers hope that the Large Hadron Collider will provide
evidence to support or refute these conjectures. They say the particle
smasher might discover extra dimensions, beyond our familiar three
spatial dimensions plus time. More dimensions are the basis of several
pre-big-bang theories.
Michio Kaku, a professor of theoretical physics at the Graduate
Center of the City University of New York, proposes that gravity,
unlike light and matter, could travel between parallel universes and
cast a "shadow" that scientists might be able to detect.
The shadow might take the form of "gravitational waves," faint
ripples in the fabric of space and time caused by violent explosions
such as the big bang. Detectors in the United States and Europe are
seeking such waves, and in the future satellites will watch for
evidence of them in space.
Turok says his cyclic theory predicts a "distinctive pattern of
gravitational waves that is very different from the one expected in the
big-bang theory ... and may prove or disprove our theory within the
next few years."
Last August, ground and satellite observations revealed what
appeared to be an enormous "hole in the universe," a mostly empty
region of the sky, 900 million light-years wide - about 5 billion
trillion miles - in the constellation Eridanus. Mersini-Houghton, a
believer in multiple universes, interpreted the empty spot as the
"footprint" of the gravitational tug of another, smaller universe
parked at the edge of our own.
"It's like someone took a giant scoop and scooped all the matter
away," she told the Columbia cosmology conference. "All these universes
are interacting with each other."
Mersini-Houghton's interpretation of the "hole" is controversial and so far lacks independent confirmation.
The oldest and most popular of the pre-big-bang theories is the
multiverse. As outlined by Martin Rees, the British astronomer royal,
in his 1997 book, "Before the Beginning: Our Universe and Others," the
theory declares that our universe is only one of many - perhaps an
infinite number - of other worlds, each differing slightly from the
others. These universes are continually forming new offspring,
sprouting off from each other rather like soap bubbles.
The big bounce hypothesis - sometimes known as the big splat -
contends that our universe was preceded by a twin that expanded to a
certain limit, then contracted, collapsed and gave birth to our world.
A leading proponent of this theory is Martin Bojowald, a theoretical
physicist at Pennsylvania State University in University Park, who
published it last year in the journal Nature.
In 2005, Kaku published a book titled "Parallel Worlds" in which he
hypothesized that there may be millions of different, parallel
universes, some that look like our own. They're invisible to us because
they lie outside our universe.
The big-bang theory found favor with the Roman Catholic Church
because it implied that the world has a single beginning at a definite
point in time, as portrayed in Genesis. At a Vatican conference in
1951, Pope Pius XII said the big bang was consistent with church
doctrine.
"Creation took place in time, therefore there is a creator, therefore God exists!" the pope declared.
The Rev. John Haught, an authority on science and religion at
Georgetown University in Washington, said the idea that there might be
many worlds and many beginnings, not just a single big bang, wouldn't
undermine Christian theology.
"Even if the universe, or multiverse, were around forever, this
would not challenge the theological explanation of the world's
existence," Haught said. "The biblical doctrine of creation ... lies at
a different level from scientific understanding. The world, theologians
say, still gets its finite being from an infinite being."
According to Francisca Cho, a professor of Buddhism and East Asian
religions at Georgetown, these pre-big-bang cosmologies are similar to
the Hindu belief in a universe that cycles endlessly through creation
and destruction.
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Dark chocolate: Half a bar per week to keep at bay the risk of heart attack
Maybe gourmands are not jumping for joy. Probably
they would have preferred bigger amounts to sup-port their passion.
Though the news is still good for them: 6.7 grams of chocolate per day
represent the ideal amount for a protective effect against inflammation
and subsequent cardiovascular disease.
A new effect, demonstrated for
the first time in a population study by the Research Laboratories of
the Catholic University in Campobasso, in collaboration with the
National Cancer Institute of Milan.
The findings, published in the last issue of the Journal of Nutrition,
official journal of the American So-ciety of Nutrition, come from one
of the largest epidemiological studies ever conducted in Europe, the
Moli-sani Project, which has enrolled 20,000 inhabitants of the Molise
region so far. By studying the participants recruited, researchers
focused on the complex mechanism of inflammation. It is known how a
chronic inflammatory state represents a risk factor for the development
of cardiovascular disease, from myocardial infarction to stroke, just
to mention the major diseases. Keeping the inflammation process un-der
control has become a major issue for prevention programs and C reactive
protein turned out to be one of the most promising markers, detectable
by a simple blood test.
The Italian team related the levels of this protein in the blood of
examined people with their usual choco-late intake. Out of 11,000,
researchers identified 4,849 subjects in good health
and free of risk factors (normal cholesterol, blood pressure and other
parameters). Among them, 1,317 did not use to eat any chocolate, while
824 used to have chocolate regularly, but just the dark one.
"We started from the hypothesis- says Romina di Giuseppe, 33, lead
author of the study- that high amounts of antioxidants contained in the
cocoa seeds, in particular flavonoids and other kinds of poly-phenols,
might have beneficial effects on the inflammatory state. Our results
have been absolutely en-couraging: people having moderate amounts of
dark chocolate regularly have significantly lower levels of C-reactive
protein in their blood. In other words, their inflammatory state is
considerably reduced." The 17% average reduction observed may appear
quite small, but it is enough to decrease the risk of cardio-vascular
disease for one third in women and one fourth in men. It is undoubtedly
a remarkable outcome".
Chocolate amounts are critical. "We are talking of a moderate
consumption. The best effect is obtained by consuming an average amount
of 6.7 grams of chocolate per day, corresponding to a small square of
chocolate twice or three times a week. Beyond these amounts the
beneficial effect tends to disappear".
From a practical point of view, as the common chocolate bar
is 100 grams, the study states that less than half a bar of dark
chocolate consumed during the week may become a healthy habit. What
about the milk chocolate? "Previous studies- the young investigator
continues- have demonstrated that milk interferes with the absorption
of polyphenols. That is why our study considered just the dark
chocolate".
Researchers wanted to sweep all the doubts away. They took into
account that chocolate lovers might consume other healthy food too, as
wine, fruits and vegetables. Or they might exercise more than others
people do. So the observed positive effect might be ascribed to other
factors but not to cocoa itself. "In order to avoid this- researcher
says- we "adjusted" for all possible "confounding" parameters. But the
beneficial effect of chocolate still remained and we do believe it is
real".
"This study- says Licia Iacoviello, Head of the Laboratory of
Genetic and Environmental Epidemiology at the Catholic University of
Campobasso and responsible for the Moli-sani Project- is the first
scientific outcome published from the Moli-sani Project. We consider
this outcome as the beginning of a large se-ries of data which will
give us an innovative view on how making prevention in everyday life,
both against cardiovascular disease and tumors".
"Maybe- Giovanni de Gaetano, director of the Research Laboratories
of the Catholic University of Cam-pobasso, adds - time has come to
reconsider the Mediterranean diet pyramid and take the dark chocolate
off the basket of sweets considered to be bad for our health".
Source: Catholic University
/////////////////////////////////////////Mysterious New 'Dark Flow' Discovered in Space By Clara Moskowitz Staff Writer posted: 23 September 2008 12:46 pm ET
As if the mysteries of dark matter and dark energy weren't vexing
enough, another baffling cosmic puzzle has been discovered.
Patches of matter in the universe seem to be moving at very
high speeds and in a uniform direction that can't be explained by any of the
known gravitational forces in the observable universe. Astronomers are calling
the phenomenon "dark flow."
The stuff that's pulling this matter must be outside
the observable universe, researchers conclude.
When scientists talk about the observable
universe, they don't just mean as far out as the eye, or even the most
powerful telescope, can see. In fact there's a fundamental limit to how much of
the universe we could ever observe, no matter how advanced our visual
instruments. The universe is thought to have formed about 13.7 billion years
ago. So even if light started travelling toward us immediately after the Big Bang,
the farthest it could ever get is 13.7 billion light-years in distance. There
may be parts of the universe that are farther away (we can't know how big the
whole universe is), but we can't see farther than light could travel over the
entire age of the universe.
Mysterious motions
Scientists discovered the flow by studying some of the
largest structures in the cosmos: giant
clusters of galaxies. These clusters are conglomerations of about a
thousand galaxies, as well as very hot gas which emits X-rays. By observing the
interaction of the X-rays with the cosmic microwave background (CMB), which is
leftover radiation from the Big Bang, scientists can study the movement of
clusters.
The X-rays scatter photons in the CMB, shifting
its
temperature in an effect known as the kinematic Sunyaev-Zel'dovich (SZ)
effect.
This effect had not been observed as a result of galaxy clusters
before, but a
team of researchers led by Alexander Kashlinsky, an astrophysicist at
NASA's Goddard Space Flight Center in Greenbelt, Md., found it when
they studied a huge catalogue of
700 clusters, reaching out up to 6 billion light-years, or half the
universe
away. They compared this catalogue to the map
of the CMB taken by NASA's Wilkinson Microwave Anisotropy Probe (WMAP)
satellite.
They discovered that the clusters were moving nearly 2
million mph (3.2 million kph)toward a region in the sky between the
constellations of Centaurus and Vela. This motion is different from the outward
expansion of the universe (which is accelerated by the force called dark
energy).
"We found a very significant velocity, and furthermore,
this velocity does not decrease with distance, as far as we can measure,"
Kashlinsky told SPACE.com. "The matter in the observable universe
just cannot produce the flow we measure."
Inflationary bubble
The scientists deduced that whatever is driving the
movements of the clusters must lie beyond the known universe.
A theory called inflation posits that the universe we see is
just a small bubble of space-time that got rapidly expanded after the Big Bang.
There could be other parts of the cosmos beyond this bubble that we cannot see.
In these regions, space-time might be very different, and
likely doesn't contain stars and galaxies (which only formed because of the
particular density pattern of mass in our bubble). It could include giant,
massive structures much larger than anything in our own observable universe.
These structures are what researchers suspect are tugging on the galaxy
clusters, causing the dark flow.
"The structures responsible for this motion have been
pushed so far away by inflation, I would guesstimate they may be hundreds of
billions of light years away, that we cannot see even with the deepest
telescopes because the light emitted there could not have reached us in the age
of the universe," Kashlinsky said in a telephone interview. "Most
likely to create such a coherent flow they would have to be some very strange
structures, maybe some warped space time. But this is just pure
speculation."
Surprising find
Though inflation theory forecasts many odd facets of the
distant universe, not many scientists predicted the dark flow.
"It was greatly surprising to us and I suspect to
everyone else," Kashlinsky said. "For some particular models of
inflation you would expect these kinds of structures, and there were some
suggestions in the literature that were not taken seriously I think until
now."
The discovery could help scientists probe what happened to
the universe before
inflation, and what's going on in those inaccessible realms we cannot see.
The researchers detail their findings in the Oct. 20 issue
of the journal Astrophysical Journal Letters.
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