Archive for the ‘University of New Hampshire’ Category

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white america

By NEIL SHAH

More white Americans are dying than being born for the first time in modern history—suggesting minorities and newcomers will play an important role in fueling the population growth America’s recovering economy needs to thrive.

The number of non-Hispanic white Americans who died in the year ended June 2012 exceeded the number who were born during that period by about 12,400, the first “natural decrease” for this group. That’s according to a U.S. Census Bureau report released Thursday and an analysis of separate data from the National Center for Health Statistics by demographer Kenneth Johnson at the University of New Hampshire. The white population edged up in absolute terms last year thanks to immigration, Census figures show.

The Census data show that as the non-Hispanic white population grows at a slower pace, the share of young Americans who are minorities is increasing, said demographer William Frey of the Brookings Institution, a left-leaning think tank in Washington. While most American children under 5 years old are still white—50.1%—that proportion is expected to fall because the majority of births have been minority children for two years in a row, a trend driven mostly by Hispanic and Asian births.

The growth rate of America’s white population has been slowing for years, but demographers had expected white births to continue exceeding deaths for some time. Census researchers had projected the “natural decrease,” or white Americans’ deaths exceeding births, would begin around 2020 and the overall white population would start falling outright several years later.

“Even during the great influenza epidemic of 1919, there was no white ‘natural decrease,’ ” said Mr. Johnson, calling the new numbers “stunning.” The epidemic of 1918-19 killed more than 600,000 Americans. The big driver of the recent numbers, Mr. Johnson said, was a drop in white births, which fell about 13% last year from 2007 levels.

The findings illustrate how rapidly the U.S. is becoming more diverse and how much of the nation’s population growth is likely to be driven by minorities and new immigrants in the years ahead.

The recent trends are partly due to the nation’s weak economic recovery, which has encouraged many young women to delay having children—a trend that demographers say could now reverse. Fertility rates dropped to low levels during the Great Depression and the 1970s malaise before rising again, according to Mark Mather of the Population Reference Bureau.

But the Census numbers underscore a more powerful, long-term demographic shift. As the nation’s white population ages, there are fewer white women of childbearing age—a trend unlikely to change—and that results in fewer white children. At the same time, young adults, whether white, black or Hispanic, are having fewer children. America’s replacement level—how many children it takes to keep population constant as people die—is about 2.1 births per woman. The fertility rate of U.S. women is about 1.9 births.

That means U.S. population growth will depend significantly on immigration. There are now 14 states where the majority of children under 5 are nonwhite, Mr. Frey said; in 2000, only five states, including the District of Columbia, had “minority majority” toddler populations.

The U.S. population is “browning from the bottom up,” Mr. Frey said.

Thanks to Mr. Cuomo for bringing this to the attention of the It’s Interesting community.

http://online.wsj.com/article/SB10001424127887324049504578541712247829092.html?mod=rss_business

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universesimulation

The conical (red) surface shows the relationship between energy and momentum in special relativity, a fundamental theory concerning space and time developed by Albert Einstein, and is the expected result if our universe is not a simulation. The flat (blue) surface illustrates the relationship between energy and momentum that would be expected if the universe is a simulation with an underlying cubic lattice.

A decade ago, a British philosopher put forth the notion that the universe we live in might in fact be a computer simulation run by our descendants. While that seems far-fetched, perhaps even incomprehensible, a team of physicists at the University of Washington has come up with a potential test to see if the idea holds water.

The concept that current humanity could possibly be living in a computer simulation comes from a 2003 paper published in Philosophical Quarterly by Nick Bostrom, a philosophy professor at the University of Oxford. In the paper, he argued that at least one of three possibilities is true:

  • The human species is likely to go extinct before reaching a “posthuman” stage.
  • Any posthuman civilization is very unlikely to run a significant number of simulations of its evolutionary history.
  • We are almost certainly living in a computer simulation.

He also held that “the belief that there is a significant chance that we will one day become posthumans who run ancestor simulations is false, unless we are currently living in a simulation.”

With current limitations and trends in computing, it will be decades before researchers will be able to run even primitive simulations of the universe. But the UW team has suggested tests that can be performed now, or in the near future, that are sensitive to constraints imposed on future simulations by limited resources.

Currently, supercomputers using a technique called lattice quantum chromodynamics and starting from the fundamental physical laws that govern the universe can simulate only a very small portion of the universe, on the scale of one 100-trillionth of a meter, a little larger than the nucleus of an atom, said Martin Savage, a UW physics professor.

Eventually, more powerful simulations will be able to model on the scale of a molecule, then a cell and even a human being. But it will take many generations of growth in computing power to be able to simulate a large enough chunk of the universe to understand the constraints on physical processes that would indicate we are living in a computer model.

However, Savage said, there are signatures of resource constraints in present-day simulations that are likely to exist as well in simulations in the distant future, including the imprint of an underlying lattice if one is used to model the space-time continuum.

The supercomputers performing lattice quantum chromodynamics calculations essentially divide space-time into a four-dimensional grid. That allows researchers to examine what is called the strong force, one of the four fundamental forces of nature and the one that binds subatomic particles called quarks and gluons together into neutrons and protons at the core of atoms.

“If you make the simulations big enough, something like our universe should emerge,” Savage said. Then it would be a matter of looking for a “signature” in our universe that has an analog in the current small-scale simulations.

Savage and colleagues Silas Beane of the University of New Hampshire, who collaborated while at the UW’s Institute for Nuclear Theory, and Zohreh Davoudi, a UW physics graduate student, suggest that the signature could show up as a limitation in the energy of cosmic rays.

In a paper they have posted on arXiv, an online archive for preprints of scientific papers in a number of fields, including physics, they say that the highest-energy cosmic rays would not travel along the edges of the lattice in the model but would travel diagonally, and they would not interact equally in all directions as they otherwise would be expected to do.

“This is the first testable signature of such an idea,” Savage said.

If such a concept turned out to be reality, it would raise other possibilities as well. For example, Davoudi suggests that if our universe is a simulation, then those running it could be running other simulations as well, essentially creating other universes parallel to our own.

“Then the question is, ‘Can you communicate with those other universes if they are running on the same platform?’” she said.

http://www.washington.edu/news/2012/12/10/do-we-live-in-a-computer-simulation-uw-researchers-say-idea-can-be-tested/