Hopkins scientist wins [Gruber award, the] top cosmology prize

Posted on July 17, 2007 by admin

Hopkins scientist wins top cosmology prize

Adam Riess, colleagues win Gruber award for discovery of 'dark energy'

By Frank D. Roylance

Sun Reporter

Originally published July 17, 2007, 9:00 AM EDT

Adam Riess, the Johns Hopkins University
astrophysicist who discovered that the universe is flying apart at an
accelerating rate in response to a still-mysterious force dubbed “dark
energy,” has won yet another top prize for his discovery.

The Peter Gruber Foundation announced today that Riess and his
co-discoverers will share the $500,000 Peter Gruber Cosmology Prize for
2007 with a competing team of scientists.

The unrestricted cash award and gold medal are given annually to
scientists for “theoretical, analytical, or conceptual discoveries
leading to fundamental advances in the field,” according to the
foundation's Web site.

The prize is described by Hopkins as “one of the most prestigious
prizes in cosmology,” and by PhysicsWeb as “the world's only award for
cosmology.”

Whichever way you look at it, “It's quite a nice honor,” said Riess, 37. “I'm very happy about it.”

Cosmology is the study of the origins and evolution of the universe as
a whole, compared to astronomy, which concentrates on celestial objects
such as planets, stars and galaxies.

Riess might have been even happier last year, when he and two
co-discoverers shared the $1 million Shaw Prize, an international award
for groundbreaking discoveries in astronomy, mathematics, life sciences
and medicine.

“The Shaw prize was far more lucrative,” said Riess, who was lead author of the first dark energy paper at the age of 28.

He split the Shaw Prize three ways, with Brian P. Schmidt, of the
Australian National University, and Saul Perlmutter, of the University
of California Berkeley.

Schmidt led the High-z Supernova Search team. Riess was a member and
first author of the High-z group's seminal 1998 paper in the journal
Science. Perlmutter led the competing Supernova Cosmology Project,
which shared in the discovery, but published second, in 1999. The two
papers are now among the most cited of the last decade.

This time, the two groups have agreed to split the award in half, with all 51 team members on the two teams receiving shares.

But then, Riess stressed, “It's not about the money. … It gets people focused on the wrong thing.”

At the time of the original discovery, Riess was a young astronomer at
Berkeley, analyzing the light from a collection of exploding stars
called Type 1a supernovae. He was trying to calculate their distance
from Earth and the speed at which they were receding with the expansion
of the universe.

To his puzzlement, it looked as though the more distant supernovae were
moving away more slowly than those that were nearer to Earth in both
space and time.

The implication was that the expansion of the universe has been
accelerating for billions of years. And that flew in the face of
cosmologists' assumptions at the time — that gravity ought to be
gradually slowing the expansion.

Something — it came to be called “dark energy,” but scientists still
don't know precisely what it is — is repelling all the matter in the
universe. It was an idea first articulated by Albert Einstein, who
later rejected it as his “biggest blunder.”

Riess thought at first that there must be a glitch in his own math. But
the more his team members checked and rechecked, the more they became
convinced the acceleration was real.

“When I was writing that paper 10 years ago, I had no idea this would
remain true. Most things in science that are really surprising are
wrong,” he said.

Once he'd published, he thought someone else would find an error in his
work. No one did. “If anything, the evidence has gotten a lot
stronger,” he said.

“I think of this as the end of the beginning for cosmology,” Riess
said. “Now, for the first time, we have plumbed the depths of the
universe and identified all the first constituents.” Now, scientists
believe dark energy constitutes 70 percent of all the matter and energy
in the universe. But they still have no idea what it is or how it works.

“Everybody has been working on follow-up studies. What is this stuff
and what is its nature?” Riess said. “It's a huge industry now. Many
people think of it as one of the two hottest things” in physics and
astronomy.

The second would be the search for planets — and ultimately habitable, or inhabited planets — around distant stars.

Riess has said he once worried aloud to his mother that he'd peaked too
early in his career. But “that was the concern of a 29-year-old,” he
said, laughing. “I've come to realize over time how rare these
discoveries are, and I've learned to appreciate it more. … You're
lucky to get such a mystery in your time to work on.”

In 1999, Riess moved to the Space Telescope Science Institute in
Baltimore to continue his work, using the Hubble Space Telescope. He
and his colleagues began publishing more results, adding evidence to
support their discovery.

In 2006 he joined the faculty at Hopkins, where he is now a professor
in the Henry A. Rowland Department of Physics and Astronomy.

This is not the first Gruber Cosmology Prize for a Hopkins scientist, nor for a Marylander.

Last year's Gruber was presented to John Mather, an astrophysicist at
the Goddard Space Flight Center, in Greenbelt. He led NASA's Cosmic
Background Explorer (COBE) team, whose discoveries earned Mather and
Berkeley's George F. Smoot the 2006 Nobel Prize in physics.

Another member of NASA's COBE team who shared the 2006 Gruber award was Hopkins astrophysicist Charles L. Bennett.

The COBE orbiting observatory measured remnants of the microwave and
infrared radiation released with the Big Bang that cosmologists believe
marked the beginning of all space, matter and time.

Slight variations in that radiation across the sky, the COBE team
discovered, marked differences in density, called “anisotropies,” that
– with gravity — gave rise, over billions of years, to the galaxies,
stars, planets and everything on them.

frank.roylance@baltsun.com

Oxford prof documents India's math contribution

Posted on July 17, 2007 by admin

Naomi Canton, Hindustan Times

Email Author
Mumbai, July 05, 2007
First Published: 03:22 IST(5/7/2007)
Last Updated: 03:25 IST(5/7/2007)

Oxford prof documents India's math contribution
http://www.hindustantimes.com/StoryPage/Print.aspx?Id=3133ffd6-29cf-45b4-bc8b-0e55e362f7af

Indians'
contribution to the development of mathematics has largely been swept
under the carpet in global history books. But a BBC crew, led by an
Oxford professor, was in the country last week to film a documentary
revealing Indians created some of the most fundamental mathematical
theories.

The West has always believed that Sir Isaac Newton, famous for
developing the laws of gravity and motion, was the brainbox behind key
branches of maths such as calculus.

In The Story of Maths, Dr
Marcus Du Sautoy, a professor of mathematics at the University of
Oxford, claims Indians made many of these breakthroughs before Newton
was born.

The Story of Maths, a four-part series, will be screened on
BBC Four in 2008. The first part looks at the development of maths in
ancient Greece, ancient Egypt and Babylon; the second focuses on India,
China and Central Asia and the rest look at how maths developed in the
West. The India reel focuses on how several Indians developed theories
in maths that were later discovered by Westerners who took credit for
them.

“A lot of people think maths was a Western invention,” said Du
Sautoy. “This programme is about how a lot of things were done here in
India before they were discovered in the West. So the programme is in
fact quite political because it shows how much we have ignored
discoveries in the East,” he said. Du Sautoy's team of a director, a
cameraman and a researcher left Mumbai on Monday.

In
India, the team filmed on trains, inside sari stores, on the backwaters
of Kerala and in rickshaws. “It's been fantastic filming in India as
the visual backdrop is so rich,” Du Sautoy said.

Aryabhatta
(476–550 AD), who calculated pi, and Brahmagupta (598-670 AD) feature
in the film, which also showcases a Gwalior temple, which documents the
first inscription of 'zero'.

“One of the biggest inventions in India was the number zero.
Indians used it long before the West did,” said Du Sautoy. “When the
West had Roman numerals there was no zero and that is why they were so
clumsy. On the other hand, Brahmagupta was one of the key
mathematicians in the world because he invented the idea of zero.”

The documentary also features the history of Kerala-born
mathematician Madhava (1350-1425) who created calculus 300 years before
Newton and German mathematician Gottfried Leibniz did, said Du Sautoy.
“We learn that Newton invented the mathematical theory calculus in the
17th century but Madhava created it earlier,” Du Sautoy said.

Chennai-born Srinivasa Ramanujan (1887-1920) also features in
the film. “He developed a lot of his own maths. He contacted English
mathematician G.H. Hardy, who persuaded him to come to Cambridge. They
began a collaboration between the analytical maths of the West and the
intuitive maths of India, and together produced brilliant theories and
amazing results.”

It was difficult for Ramanujan to travel to Britain because
he was a Brahmin and not allowed to travel by sea. “He had to almost
give up his religion but maths was also like a religion to him. He had
no one to talk to in India because at that time no one was interested
in his ideas,” said Du Sautoy.

Modern humans reached India early (≥ 74,000 years ago)

Posted on July 16, 2007 by admin

Modern humans reached India early

N. Gopal Raj

Evidence found in excavations by international team of scientists at Jwalapuram in Kurnool district of Andhra Pradesh

— Photo: Ravi Korisettar

Ravi Korisettar and Michael Petraglia (in the foreground) at one of the excavation sites.

THIRUVANANTHAPURAM: In the course of archaeological excavations
at Jwalapuram in Kurnool district of Andhra Pradesh, an international
team of scientists has found evidence that anatomically modern humans
are likely to have reached India before a massive volcanic eruption in
what is today Indonesia occurred tens of thousands of years ago.

“Super-eruption”

The “super-eruption” of the Toba volcano in Sumatra some 74,000
years ago was the largest volcanic event to have occurred in the last
two million years and the ash thrown up high into the atmosphere by
that cataclysmic explosion reached India too, said Ravi Korisettar of
the Department of History and Archaeology at Karnatak University in
Dharwad, Karnataka.

During five years of excavations at Jwalapuram, Indian, British, and
Australians scientists unearthed fine stone flakes that had been turned
into tools for various purposes.

The stone tools were to be found in layers of earth above as well as
below the fine ash from the Toba super-eruption, the scientists noted
in a paper published in the latest issue of the journal Science.

“Volcanic winter”

It had been thought that the vast amounts of volcanic ash flung
into the atmosphere by the eruption could have blocked sunlight and
produced a “volcanic winter” that decimated the humans living then. But
the evidence from the Jwalapuram excavations, however, suggests that
the volcanic eruption did not have such a catastrophic impact on the
early human population there.

Stone tools

The stone tools also pointed to a more exciting possibility. The
stone tool assemblages found in Jwalapuram were “very similar to ones
that we see produced in Africa at the same time,” said Michael
Petraglia of the Leverhulme Centre for Human Evolutionary Studies at
the University of Cambridge in the U.K, the first author of the paper.

Those stone tools in Africa had been produced by modern humans.

“Closer affinities”

In the Science paper, the researchers noted that the
techniques used for making the stone tools at Jwalapuram suggested
“closer affinities” to African Middle Stone Ages traditions than to
contemporaneous Eurasian ones. T his finding is significant because
genetic studies of tell-tale patterns in the DNA of people living in
various parts of the world have supported the view that all modern
humans arose in Africa.

It is believed that these modern humans then migrated out of Africa and settled all across the globe.

“So what we are saying is that modern humans probably dispersed from
Africa into India at a very early date, earlier than anyone has
suggested before,” Dr. Petraglia told this correspomndent.

There is a hypothesis that modern humans could have taken the
“southern route of dispersal,” utilising the coastlines to travel from
Africa, through Arabia, across the Indian subcontinent and then into
South-East Asia and finally into Australia, he said. The presence of
modern humans in India at the time of the Toba super-eruption would be
consistent with humans having used the southern route, but would remain
speculative till further excavations were carried out in the Indian
subcontinent and Arabian peninsula, remarked the scientists in their
journal paper.

Key role

India has a played a key role in the migration of modern humans
out of Africa, says K. Thangaraj of the Centre for Cellular and
Molecular Biology at Hyderabad. In a paper published in Science
two years ago, Dr. Thangaraj and others held that genetic lineages to
be found among Andaman islanders supported an out-of-Africa migration
by modern humans some 50,0000 to 70,000 years ago.

Archaeological data

Dr. Korisettar is, however, sceptical about modern humans opting for a coastal route for their migration.

There was currently no archaeological evidence of such ancient human
migrations along India's west coast and into southern Tamil Nadu.
Rather, the available archaeological data favoured a continental route
whereby early humans came through the Bolan and Khyber passes to the
north-western parts of the Indian subcontinent and then into Rajasthan
before dispersing to other parts of the country, he added.

Clues to Rising Seas Are Hidden in Polar Ice

Posted on July 15, 2007 by admin

Clues to Rising Seas Are Hidden in Polar Ice

By Juliet Eilperin

Washington Post Staff Writer
Monday, July 16, 2007; Page A06

Few consequences of global warming pose
as severe a threat to human society as sea-level rise. But scientists
have yet to figure out how to predict it.

And not knowing what to expect, policymakers and others are hamstrung in considering how to try to prevent it or prepare for it.

To calculate sea-level rise, the key thing researchers need to understand is the behavior of the major ice sheets that cover Greenland and Antarctica.
The disintegration of one would dramatically raise the ocean. But while
computer models now yield an increasingly sophisticated understanding
of how a warming atmosphere would behave, such models have yet to fully
encapsulate the complex processes that regulate ice sheet behavior.

“The
question is: Can we predict sea level? And the answer is no,” said
David Holland, who directs New York University's Center for Atmosphere
Ocean Science. Holland,
an oceanographer, added that this may mean researchers will just have
to watch the oceans to see what happens: “We may observe the change
much more than we ever predict it.”

In its executive summary report for policymakers in February, the Intergovernmental Panel on Climate Change,
composed of hundreds of leading climate scientists, barely hazarded a
guess on sea level, predicting that it would rise between 7.8 inches
and two feet by the end of the century. However, the United Nations-sponsored
panel — which operated under the assumption that, by 2100, the
Greenland ice sheet would lose some mass but that the Antarctic ice
sheet would gain some — did not venture a best estimate or an upper
limit for possible sea-level rise.

“There's a continent of topography sitting
under Antarctica,” Vaughn said. “Everything there has an impact on how
the ice sheet flows, and very little of that has been mapped.”

Researchers
are also trying to measure the layer of water that lies under the ice
sheets, as that also helps regulate ice stream flows.

“They're essentially afloat on their own sub-glacial water, even if
there's not much water there,” said Garry Clarke, a glaciology
professor at the University of British Columbia. “We don't know very much about how water flows underneath ice sheets.”

Another
uncertainty is how much the oceans surrounding the ice sheets are
warming, something that is difficult to measure because the areas are
remote. Vaughan and his colleagues suspect that warmer waters around
Antarctica have contributed to melting the Western Antarctic ice sheet,
but there is little good data because few ships venture there.

Researchers are now going to extraordinary lengths to collect the data they need. Holland at NYU
recently returned from a trip to Greenland, where he was collecting
information about the Ilulissat glacier, which has doubled its speed
over the past decade as it flows toward the ocean and melts. To test
the temperature and salinity of the water surrounding the glacier,
Holland and other researchers had to hover in a helicopter and lower
their instruments into an opening in the ice.

“It's kind of beautiful, and scary and fun,” he said.

Even
with better data, scientists find it difficult to enter the information
into computer models. Most models do not attempt to calculate what
could happen to ice sheets at their edges.

Adding to the
challenge, Oppenheimer said, is that models “are only good at
explaining things that happen at a large scale. Ice sheets are very
complex beasts, and the water moves at a very small scale.”

Ice
streams move along narrow channels, and plugging such detail into a
computer model takes a long time. But without that level of detail, the
results are incomplete.

Researchers have made some progress in
ice sheet science over the past decade by using satellites to measure
the sheets' changing mass.

Last month, for example, a team of NASA
and university scientists used readings from NASA's QuikScat satellite
to measure snow accumulation and melt in Antarctica from July 1999
through July 2005. They discovered that broad areas of snow had melted
in west Antarctica in January 2005 in response to warmer temperatures.
The finding was surprising because Antarctica had shown relatively
little warming in the recent past.

Konrad Steffen, director of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder,
who led the study, said increases in snowmelt “definitely could have an
impact on larger-scale melting of Antarctica's ice sheets if they were
severe or sustained over time.”

Because ice sheet modeling has
not ranked as a high priority for government laboratories and has not
been integrated into large-scale climate models, scientists from around
the world are now collaborating to develop more sophisticated models to
inform policymakers about potential sea-level rise. The researchers
have convened two major meetings this year, one at the NOAA Geophysical
Fluid Dynamics Laboratory at Princeton University and one at the University of Texas at Austin, in an effort to generate a new generation of ice sheet models.

Vaughan,
who attended both conferences, said he is hopeful that he and others
will solve the question of ice sheet modeling by the time he ends his
career: “It will be 15 years before I retire, and I want it nailed by
then.”

But other researchers are less optimistic. Holland, who
like Vaughan is in his mid-40s, doubts that scientists will master the
problem before greenhouse gas emissions trigger significant melting of
the ice sheets that he studies.

“We will get there eventually,
but it won't be for a long time. It won't be in my lifetime,” Holland
said. “There's no plan; there's no program. There's no one responsible
for sea-level rise.”

Self-centered cultures narrow your viewpoint

Posted on July 14, 2007 by admin

Self-centered cultures narrow your viewpoint

14:06 12 July 2007
NewScientist.com news service
Roxanne Khamsi

When it comes to putting yourself in the shoes of others, cultures
that emphasise interdependence over individualism may have the upper
hand.

In
a new psychological experiment, Chinese students outperformed their US
counterparts when ask to infer another person's perspective. The
researchers say the findings help explain how misunderstandings can
occur in cross-cultural communication.

In
the experiment, psychologists Boaz Keysar and Shali Wu at the
University of Chicago, Illinois, US, recruited 40 students. Half of the
volunteers were non-Asians who had grown up in the US, and the other
half were native Mandarin speakers who had very recently emigrated from
various parts of China.

The
volunteers played a game in which they had to follow the instructions
of a person sitting across the table from them, an individual known as
the 'director'.

Researchers
placed a grid structure between the two people consisting of small
compartments, some of which contained objects such as wood blocks, toy
bunnies and sunglasses. Some of the individual
compartments were covered on one side with cardboard so that they were
blocked from the view of the director – only the study subjects could
see the objects inside.

Off the charts

The
volunteers had to follow the instructions of the director and move
named objects from one compartment to another. But – as a sneaky trick
– the researchers sometimes placed two objects of the same kind in the
grid. In this case, the subjects would have to consider the director’s
view to know which object she was referring to.

For
example, the grid sometimes contained two wooden blocks, one of which
sat in a compartment hidden to the director. The director would then
ask the subject to “move the wooden block to a higher square in the
grid”.

Chinese
students would immediately understand which wooden block to move – the
one visible to both them and the director. Their US counterparts,
however, did not always catch on.

“They
would ask 'Which block?' or 'You mean the one on the right?”, explains
Keysar. “For me it was really stunning because all of the information
is there. You don't need to ask,” he adds.

While
65% of the American participants asked this type of question, only one
of the 20 Chinese subjects did so, equating to just 5%.

“That's
a huge difference – it's off the charts,” says Richard Nisbett, a
psychologist at the University of Michigan in Ann Arbor, Michigan, US,
who studies differences between Western and Asian cultures.

Language link

The
US volunteers were also slower in reacting when asked to move an object
when there was a duplicate in the grid that only they could see. They
generally took about 30% longer to complete such instructions from the
director.

In contrast, such duplicate objects did not slow the speed at which Chinese participants responded.

Keysar
believes the Chinese students had an easier time understanding the
director’s perspective because they come from a more collectivist
society than their US counterparts. He speculates, for example, that
compared with children in China, youngsters in the US are more likely
to feel that it is “all about them”.

In
another example, he describes how a Texas corporation “aiming to
improve productivity, told its employees to look in the mirror and say
'I am beautiful' 100 times before coming to work. In contrast, a
Japanese supermarket instructed its employees to begin their day by
telling each other 'you are beautiful'.”

Nisbett
adds that in some Asian cultures people use less blunt language, making
it necessary for them to read between the lines, and imagine the
perspective of the individual with whom they are speaking.

He
also says that the new findings could help us head off
misunderstandings between people from Asian and Western societies: “We
are less likely to step on each other's toes if we are aware of one
another's cultural differences.”

Previous research has shown that culture can influence very basic behaviours, such as how we see objects.

Journal reference: Psychological Science (vol 18, p 600-606)

Posthuman Destinies

Science, Culture, Integral Yoga

Author Archives: admin

Hopkins scientist wins [Gruber award, the] top cosmology prize

Hopkins scientist wins top cosmology prize

Oxford prof documents India's math contribution

Modern humans reached India early (≥ 74,000 years ago)

Clues to Rising Seas Are Hidden in Polar Ice

Clues to Rising Seas Are Hidden in Polar Ice

Graphic

Graphic

Monday, 11 a.m. ET

Self-centered cultures narrow your viewpoint

Self-centered cultures narrow your viewpoint

Language link