from-dust-of-stars: Oh my fucking… This is so hot!

from-dust-of-stars: Creepy, cool abandoned cities. Wild, fucking wild!

Check out more via link, Source: http://all-that-is-interesting.com/7-creepy-abandoned-cities from-dust-of-stars: Creepy, cool abandoned cities. Wild, fucking wild!

Check out more via link, Source: http://all-that-is-interesting.com/7-creepy-abandoned-cities from-dust-of-stars: Creepy, cool abandoned cities. Wild, fucking wild!

Check out more via link, Source: http://all-that-is-interesting.com/7-creepy-abandoned-cities

from-dust-of-stars: Creepy, cool abandoned cities. Wild, fucking wild!

Check out more via link, Source: http://all-that-is-interesting.com/7-creepy-abandoned-cities

from-dust-of-stars: LMFAO.. What a way to come out, LOL. This is a classic!

from-dust-of-stars: So damn fine beauty. Damn!

from-dust-of-stars: So damn fine beauty. Damn!

from-dust-of-stars: WTF, are you shocked to learn that ‘Everything Republicans Believe is Wrong’? Greed, denial, inequality, American politics for sale to the highest bidder… Welcome to the American oligarchy. Damn sickening, yet fascinating read.

Six Studies That Show Everything Republicans Believe is Wrong

By Sean McElwee
April 23, 2014 9:00 AM ET

The great 20th-century economist John Maynard Keynes has been widely quoted as saying, “When the facts change, I change my mind. What do you do, sir?” Sadly, in their quest to concentrate economic and political power in the hands of the wealthiest members of society, today’s Republicans have held the opposite position – as the evidence has piled up against them, they continue spreading the same myths. Here are six simple facts about the economy that Republicans just can’t seem to accept:​

1. The Minimum Wage Doesn’t Kill Jobs.

The Republican story on the minimum wage takes the inordinately complex interactions of the market and makes them absurdly simple. Raise the price of labor through a minimum wage, they claim, and employers will hire fewer workers. But that’s not how it works. In the early Nineties, David Card and Alan Krueger found “no evidence that the rise in New Jersey’s minimum wage reduced employment at fast-food restaurants in the state.” Since then, international, national and state-level studies have replicated these findings – most recently in a study by three Berkeley economists. Catherine Ruetschlin, a policy analyst at Demos, has argued that a higher minimum wage would actually “boost the national economy” by giving workers more money to spend on goods and services. The most comprehensive meta-study of the minimum wage examined 64 studies and found “little or no evidence” that a higher minimum wage reduces employment. There is however, evidence that a higher minimum wage lifts people out of poverty. Raise away!

2. The Stimulus Created Millions of Jobs.

In the aftermath of the 2007 recession, President Obama invested in a massive stimulus. The Republican belief that markets are always good and government is always bad led them to argue that diverting resources to the public sector this way would have disastrous results. They were wrong: The stimulus worked, with the most reliable studies finding that it created millions of jobs. The fact that government stimulus works – long denied by Republicans (at least, when Democrats are in office) – is a consensus among economists, with only 4 percent arguing that unemployment would have been lower without the stimulus and only 12 percent arguing that the costs outweigh the benefits.

3. Taxing The Rich Doesn’t Hurt Economic Growth.

Republicans believe that the wealthy are the vehicles of economic growth. Starting with Ronald Reagan in the 1980s, they tried cutting taxes on the rich in order to unleash latent economic potential. But even the relatively conservative Martin Feldstein has acknowledged that investment is driven by demand, not supply; if there are viable investments to be made, they will be made regardless of tax rates, and if there are no investments to be made, cutting taxes is merely pushing on a string. Thomas Piketty and Emmanuel Saez, two of the eminent economists of inequality, find no correlation between marginal tax rates and economic growth.

In fact, what hurts economic growth most isn’t high taxes – it’s inequality. Two recent IMF papers confirm what Keynesian economists like Joseph Stiglitz have long argued: Inequality reduces the incomes of the middle class, and therefore demand, which in turn stunts growth. To understand why, imagine running a car dealership. Would you prefer if 1 person in your time owned 99% of the wealth and the rest of the population had nothing, or if wealth was distributed more equally, so that more people could purchase your cars?

Every other country in the Organization for Economic Cooperation and Development has far lower levels of inequality than the United States. Since there are no economic benefits of inequality, why hasn’t the right conceded the argument? Because it’s based on class interest, not empirical evidence.

4. Global Warming is Caused by Humans.

Even as global warming is linked to more and more extreme weather events, more than 56 percent of Republicans in the current congress deny man-made global warming. In fact, the infamous Lutz memo shows that Republicans have actually created a concerted campaign to undermine the science of global warming. In the leaked memo, Frank Lutz, a Republican consultant, argues that, “The scientific debate is closing [against us] but not yet closed. There is still a window of opportunity to challenge the science.”

In truth, the science of global warming is not up for debate. James Powell finds that over a one year period, 2,258 articles on global warming were published by 9,136 authors. Of those, only one, from the Herald of the Russian Academy of Sciences, rejected man-made global warming. That one article was likely motivated by the Russian government’s interest in exploiting arctic shale. Another, even more comprehensive study, examining 11,944 studies over a 10-year period, finds that 97 percent of scientists accepted the scientific consensus that man-made global warming is occurring.

This is not an abstract academic debate. The effects of climate change will be devastating, and poor countries will be hurt the worst. We’ve already seen the results. Studies have linked global warming to Hurricane Sandy, droughts and other extreme weather events. More importantly, doing nothing will end up being far more expensive than acting now. One study suggests it could wipe out 3.2% of global GDP annually.

5. The Affordable Care Act is Working

President Obama’s centrist healthcare bill was informed by federalism (delegating power to the states) and proven technocratic reforms (like a board to help doctors discern which treatments would be most cost-effective). Republicans, undeterred, decried it as Soviet-style communism based on “death panels” – never mind the fact that the old system, which rationed care based on income, is the one that left tens of thousands of uninsured people to die.

From the beginning, Republicans have predicted disastrous consequences or Obamacare, none of which came true. They predicted that the ACA would add to the deficit; in fact, it will reduce the deficit. They claimed the exchanges would fail to attract the uninsured; they met their targets. They said only old people would sign up; the young came out in the same rates as in Massachusetts. They predicted the ACA would drive up healthcare costs; in fact it is likely holding cost inflation down, although it’s still hard to discern how much of the slowdown was due to the recession. In total, the ACA will ensure that 26 million people have insurance in 2024 who would have been uninsured otherwise.

It’s worth noting that every time the CBO estimates how much Obamacare will cost, the number gets lower. Odd how we’ve never heard Republicans say that.

6. Rich people are no better than the rest of us.

Politicians on the right like to pretend that having money is a sign of hard work and morality – and that not having money is a sign of laziness. This story is contradicted by human experience and many religious traditions (Jesus tells a graphic story about a rich man who refused to help the poor burning in hell). But it’s also contradicted by the facts – more and more rich people are getting their money through inheritances, and science shows that they are no more benevolent than others.

More and more, the wealthy in America are second or third generation. For instance, the Walton family, heirs to the Walmart fortune, own more wealth than the poorest 40 million Americans. Thomas Philippon and Ariell Reshef have found that 30 to 50 percent of the wage difference between the financial sector and the rest of the private sector was due to unearned “rent,” or money they gained through manipulating markets. Josh Bivens and Larry Mishel found the same thing for CEOs – their increased pay hasn’t been correlated to performance.

If rich people haven’t really earned their money, are they at least doing any good with it? Studies find that the wealthy actually give less to charity as a proportion of their income than middle-class Americans, even though they can afford more. Worse, they use their supposed philanthropy to avoid taxes and finance pet projects. Research by Paul Piff finds that the wealthy are far more likely to exhibit narcissistic tendencies. “The rich are way more likely to prioritize their own self-interests above the interests of other people,” Piff recently told New Yorkmagazine. “It makes them more likely to exhibit characteristics that we would stereotypically associate with, say, assholes.”

Source: http://www.rollingstone.com/politics/news/six-studies-that-show-everything-republicans-believe-is-wrong-20140423

from-dust-of-stars: WTF, are you shocked to learn that ‘Everything Republicans Believe is Wrong’? Greed, denial, inequality, American politics for sale to the highest bidder… Welcome to the American oligarchy. Damn sickening, yet fascinating read.

Six Studies That Show Everything Republicans Believe is Wrong

By Sean McElwee
April 23, 2014 9:00 AM ET

The great 20th-century economist John Maynard Keynes has been widely quoted as saying, “When the facts change, I change my mind. What do you do, sir?” Sadly, in their quest to concentrate economic and political power in the hands of the wealthiest members of society, today’s Republicans have held the opposite position – as the evidence has piled up against them, they continue spreading the same myths. Here are six simple facts about the economy that Republicans just can’t seem to accept:​

1. The Minimum Wage Doesn’t Kill Jobs.

The Republican story on the minimum wage takes the inordinately complex interactions of the market and makes them absurdly simple. Raise the price of labor through a minimum wage, they claim, and employers will hire fewer workers. But that’s not how it works. In the early Nineties, David Card and Alan Krueger found “no evidence that the rise in New Jersey’s minimum wage reduced employment at fast-food restaurants in the state.” Since then, international, national and state-level studies have replicated these findings – most recently in a study by three Berkeley economists. Catherine Ruetschlin, a policy analyst at Demos, has argued that a higher minimum wage would actually “boost the national economy” by giving workers more money to spend on goods and services. The most comprehensive meta-study of the minimum wage examined 64 studies and found “little or no evidence” that a higher minimum wage reduces employment. There is however, evidence that a higher minimum wage lifts people out of poverty. Raise away!

2. The Stimulus Created Millions of Jobs.

In the aftermath of the 2007 recession, President Obama invested in a massive stimulus. The Republican belief that markets are always good and government is always bad led them to argue that diverting resources to the public sector this way would have disastrous results. They were wrong: The stimulus worked, with the most reliable studies finding that it created millions of jobs. The fact that government stimulus works – long denied by Republicans (at least, when Democrats are in office) – is a consensus among economists, with only 4 percent arguing that unemployment would have been lower without the stimulus and only 12 percent arguing that the costs outweigh the benefits.

3. Taxing The Rich Doesn’t Hurt Economic Growth.

Republicans believe that the wealthy are the vehicles of economic growth. Starting with Ronald Reagan in the 1980s, they tried cutting taxes on the rich in order to unleash latent economic potential. But even the relatively conservative Martin Feldstein has acknowledged that investment is driven by demand, not supply; if there are viable investments to be made, they will be made regardless of tax rates, and if there are no investments to be made, cutting taxes is merely pushing on a string. Thomas Piketty and Emmanuel Saez, two of the eminent economists of inequality, find no correlation between marginal tax rates and economic growth.

In fact, what hurts economic growth most isn’t high taxes – it’s inequality. Two recent IMF papers confirm what Keynesian economists like Joseph Stiglitz have long argued: Inequality reduces the incomes of the middle class, and therefore demand, which in turn stunts growth. To understand why, imagine running a car dealership. Would you prefer if 1 person in your time owned 99% of the wealth and the rest of the population had nothing, or if wealth was distributed more equally, so that more people could purchase your cars?

Every other country in the Organization for Economic Cooperation and Development has far lower levels of inequality than the United States. Since there are no economic benefits of inequality, why hasn’t the right conceded the argument? Because it’s based on class interest, not empirical evidence.

4. Global Warming is Caused by Humans.

Even as global warming is linked to more and more extreme weather events, more than 56 percent of Republicans in the current congress deny man-made global warming. In fact, the infamous Lutz memo shows that Republicans have actually created a concerted campaign to undermine the science of global warming. In the leaked memo, Frank Lutz, a Republican consultant, argues that, “The scientific debate is closing [against us] but not yet closed. There is still a window of opportunity to challenge the science.”

In truth, the science of global warming is not up for debate. James Powell finds that over a one year period, 2,258 articles on global warming were published by 9,136 authors. Of those, only one, from the Herald of the Russian Academy of Sciences, rejected man-made global warming. That one article was likely motivated by the Russian government’s interest in exploiting arctic shale. Another, even more comprehensive study, examining 11,944 studies over a 10-year period, finds that 97 percent of scientists accepted the scientific consensus that man-made global warming is occurring.

This is not an abstract academic debate. The effects of climate change will be devastating, and poor countries will be hurt the worst. We’ve already seen the results. Studies have linked global warming to Hurricane Sandy, droughts and other extreme weather events. More importantly, doing nothing will end up being far more expensive than acting now. One study suggests it could wipe out 3.2% of global GDP annually.

5. The Affordable Care Act is Working

President Obama’s centrist healthcare bill was informed by federalism (delegating power to the states) and proven technocratic reforms (like a board to help doctors discern which treatments would be most cost-effective). Republicans, undeterred, decried it as Soviet-style communism based on “death panels” – never mind the fact that the old system, which rationed care based on income, is the one that left tens of thousands of uninsured people to die.

From the beginning, Republicans have predicted disastrous consequences or Obamacare, none of which came true. They predicted that the ACA would add to the deficit; in fact, it will reduce the deficit. They claimed the exchanges would fail to attract the uninsured; they met their targets. They said only old people would sign up; the young came out in the same rates as in Massachusetts. They predicted the ACA would drive up healthcare costs; in fact it is likely holding cost inflation down, although it’s still hard to discern how much of the slowdown was due to the recession. In total, the ACA will ensure that 26 million people have insurance in 2024 who would have been uninsured otherwise.

It’s worth noting that every time the CBO estimates how much Obamacare will cost, the number gets lower. Odd how we’ve never heard Republicans say that.

6. Rich people are no better than the rest of us.

Politicians on the right like to pretend that having money is a sign of hard work and morality – and that not having money is a sign of laziness. This story is contradicted by human experience and many religious traditions (Jesus tells a graphic story about a rich man who refused to help the poor burning in hell). But it’s also contradicted by the facts – more and more rich people are getting their money through inheritances, and science shows that they are no more benevolent than others.

More and more, the wealthy in America are second or third generation. For instance, the Walton family, heirs to the Walmart fortune, own more wealth than the poorest 40 million Americans. Thomas Philippon and Ariell Reshef have found that 30 to 50 percent of the wage difference between the financial sector and the rest of the private sector was due to unearned “rent,” or money they gained through manipulating markets. Josh Bivens and Larry Mishel found the same thing for CEOs – their increased pay hasn’t been correlated to performance.

If rich people haven’t really earned their money, are they at least doing any good with it? Studies find that the wealthy actually give less to charity as a proportion of their income than middle-class Americans, even though they can afford more. Worse, they use their supposed philanthropy to avoid taxes and finance pet projects. Research by Paul Piff finds that the wealthy are far more likely to exhibit narcissistic tendencies. “The rich are way more likely to prioritize their own self-interests above the interests of other people,” Piff recently told New Yorkmagazine. “It makes them more likely to exhibit characteristics that we would stereotypically associate with, say, assholes.”

Source: http://www.rollingstone.com/politics/news/six-studies-that-show-everything-republicans-believe-is-wrong-20140423

from-dust-of-stars: Keeping it real - important read on income inequality. Are we already an Oligarchy? Funny when a conservative points out the unpleasant facts that conservatives so dearly deny!

The right’s new public enemy No. 1: Why Thomas Piketty has conservatives terrified

His new book reveals just how perilous capitalism can be. No wonder Ross Douthat is trying to brand him a Marxist

LYNN STUART PARRAMORE, ALTERNET
WEDNESDAY, APR 23, 2014 01:50 PM CDT

This article originally appeared on AlterNet.

Thomas Piketty is no radical. His 700-page book Capital in the 21st Century is certainly not some kind of screed filled with calls for class warfare. In fact, the wonky and mild-mannered French economist opens his tome with a description of his typical Gen X abhorrence of what he calls the “lazy rhetoric of anticapitalism.” He is in no way, shape, or form a Marxist. As fellow-economist James K. Galbraith has underscored in his review of the book, Piketty “explicitly (and rather caustically) rejects the Marxist view” of economics.

But he does do something that gives right-wingers in America the willies. He writes calmly and reasonably about economic inequality, and concludes, to the alarm of conservatives, that there is no magical force that drives capitalist societies toward shared prosperity. Quite the opposite. He warns that if we don’t do something about it, we may end up with a society that is more top-heavy than anything that has come before — something even worse than the Gilded Age.

For this, in America, you get branded a crazed Communist by the right. In this past weekend’sNew York Times, Ross Douthat sounds the alarm in an op-ed ominously tited “Marx Rises Again.” The columnist hints that he and his fellow pundits have only pretended to read the book but nevertheless feel comfortable making statements like “Yes, that’s right: Karl Marx is back from the dead” about Piketty. TheNational Review‘s James Pethokoukis joins in the games with a silly article called “The New Marxism” in which he repeats the nonsense that Piketty is some sort of Marxist apologist.

For Douthat and his tribe, the proposition that unfettered capitalism marches toward gross inequality is not a conclusion based on carefully collected data, strenuous research and a sweeping view of history. It has to be a Communist plot.

The very heft of Piketty’s book is terrifying to the Douthats, and no wonder they don’t dare to read it, because if they did, they would find chart after chart, data set after data set, and hundreds of years worth of economic history scrutinized.

Income and wealth inequality have not been comprehensively studied to date, which has to do with the paucity of historical data and the difficulties of making comparisons between countries and populations when there are so many variables. Piketty’s contribution is to painstakingly comb over the available data and illuminate trends that would leave no reasonable person in doubt of the fact that capitalism’s inherent dynamics create inequality, and that only our express intervention, in the form of things like a global wealth tax, investment in skills and training, and the diffusion of knowledge can lead us to a different outcome.

To the horror of conservatives, the public is rushing out to buy this weighty economic treatise: the book is #1 on Amazon and has hit the New York Timesbestseller list. A public that not only inuits conservative economic nonsense but has the detailed information to back up that gut instinct is just too awful for words.

Piketty is scaring the right because he is a serious researcher and a calm, disciplined observer who writes in measured tones. But for conservatives who have based the last several decades of economic discussion on mythology, this dose of reality has come at them like a chillling blast of Arctic air.

Let them have their hysteria. It’s a testimony to the utter bankruptcy of their ideas.

Memo to liberals and progressives: making Piketty into a rock star isn’t helping, either. Let’s let the facts speak for themselves.

Source: http://www.salon.com/2014/04/23/the_rights_new_public_enemy_no_1_why_thomas_picketty_has_conservatives_terrified_partner/

from-dust-of-stars: Freaking interesting! 

Mapping the road to quantum gravity.  Date: April 23, 2014

Source: Perimeter Institute for Theoretical Physics

Summary: The road uniting quantum field theory and general relativity — the two great theories of modern physics — has been impassable for 80 years. Could a tool from condensed matter physics finally help map the way?

Perimeter Associate Faculty member Sung-Sik Lee is a condensed matter physicist — but he has his eye on quantum gravity.
Lee lays out the problem: “Physics has one theory to describe how planets orbit the sun and another to describe how electrons ‘orbit’ an atomic nucleus. Both theories — gravity as described by Einstein’s general relativity and quantum field theory — are great triumphs. Both are well-tested and powerful. The trouble is, we can’t use both at once.”
Relativity says that spacetime is smooth, and only big things can warp it, in ways that are exactly known. Quantum theory says that the smallest parts of the universe are constantly fluctuating and dramatically uncertain. How can something be both smooth and fluctuating, both exact and uncertain? How, in other words, can we make a quantum theory of gravity?

Physicists simply don’t know. Researchers in both string theory and loop quantum gravity have made progress, but a fully functional unified theory has remained out of reach for more than 80 years.

Enter — of all things — condensed matter physics.

Introducing the renormalization group

As far as the condensed matter physicists are concerned, it’s all about scale.
In all of physics, but particularly in condensed matter, our descriptions of physical systems depend on the scale at which we look at them. For instance, if you wanted to know how your tea would spread across the table if you spilled it, you would describe the puddle with hydrodynamics, and completely ignore the fact that the tea actually consists of single molecules and has a complex microscopic structure. But if you wanted to know details about how a very small drop behaved, you would have to change the description to one that takes the microscopic structure into account.
Condensed matter physicists have developed a powerful suite of mathematical tools for “flowing” a theory at one scale into a theory at a different scale. These tools are collectively known as the renormalization group, or RG.

RG tools allow physicists to take what they know about tea molecules and move seamlessly to a description of a spreading puddle. Like the zoom on a camera, the RG changes the distance scale. It’s perhaps simplistic, but nonetheless true, that distance scales are exactly what separates quantum theory from gravitational theory — one is the physics of the small and one is the physics of the large. Could the renormalization group be the tool that finally unites them?

Maybe. A growing body of researchers, from around the world, is trying to find out. Lee wants to use the RG to better understand the relationship between quantum theory and gravity. Specifically, he wants to make a constructive proof of the AdS/CFT correspondence.

Introducing the AdS/CFT conjecture

At Perimeter and places like it, the phrase “AdS/CFT correspondence” comes up a lot. If it’s always sounded like Greek to you, here’s some background.

AdS is short for anti-de Sitter space. When we say “space” in this case, we mean not the cosmic emptiness of outer space, but space in the mathematical sense — space as geometry. If you imagine drawing a triangle on a piece of paper and another on the surface of a sphere, you might intuit that the rules of geometry depend on the space you’re dealing with. Space as a piece of paper is technically called Euclidean space. Space as the surface of a sphere is technically called elliptical space.

Anti-de Sitter space is elliptical space that obeys the tenets of special relativity — elliptical space that can stretch or contract in extreme circumstances. When physicists say that gravity bends space like a bowling ball on a rubber sheet, anti-de Sitter space is probably the space they have in mind. Thus, the “AdS” part of AdS/CFT refers to a particular description of gravity.

CFT, meanwhile, is short for conformal field theory. Field theories are the language of quantum mechanics. They describe how a field — an electrical field, for example — might change over space and time. Conformal field theories are a subclass of field theories where certain properties of the theory don’t change when scale is changed.
The AdS/CFT correspondence states that for every conformal field theory, there is a corresponding theory of gravity with one more dimension. A two-dimensional CFT would correspond to a three-dimensional theory of gravity, for instance. The two theories look very different, but the AdS/CFT correspondence says that, mathematically, they are identical.

Using the renormalization group to prove the AdS/CFT conjecture
Proposed by Juan Maldecena in 1997, the AdS/CFT correspondence — which is also known as the Maldecena duality or the gauge/gravity duality — has been hugely fruitful. There were intractable problems in field theory that could suddenly be solved in AdS, and deep questions about gravity that could suddenly be addressed via well-explored field theories. But despite its success, AdS/CFT remains a conjecture: it’s never been proved.

"There is a lot of evidence for the conjecture, but there’s no proof," says Lee, who is jointly appointed to Perimeter and to McMaster University. "We know for sure that it works in some special cases. We believe that it applies more generally in other cases, but we don’t know how to make the connection."

What’s needed, Lee says, is constructive proof. That is, he’s not satisfied with knowing that A equals B — he wants to map the path between A and B. That path could then be followed from A’ to B’, from A* to B* — from field theory to gravity. Lee hopes the renormalization group can be that path.

The idea that RG is behind the AdS/CFT correspondence is not new. The AdS/CFT conjecture maps an N dimensional field theory into a N+1 dimensional theory of gravity. The extra dimension is widely interpreted as a length scale (for reasons not discussed here). Since moving theories from one length scale to another is exactly what the renormalization group is for, many experts believe that RG will be key to any proof of the AdS/CFT conjecture.

But there’s still a problem.

Toward a quantum renormalization group

"The problem with the renormalization group is that it predicts things in a way that is deterministic and classical," Lee says. For example, consider one of basic things physicists need to compute: the coupling constant, which predicts the strength of the force between two objects. "Say I have a coupling constant and it has value X at one scale. If I double the length scale, the renormalization group will tell me exactly what the new coupling constant will be."

That sounds like the good news, but it’s actually the bad news. “We are talking about quantum gravity,” says Lee. “Coupling constants will not be exactly known. They will be quantum and dynamical.”

To address this, Lee is working on an extension of the renormalization group which he calls the quantum renormalization group. Whereas traditional RG makes the coupling constants “flow” along a smooth and deterministic path from one exact value to another, Lee’s quantum RG will have built in uncertainty about the start and end points of that path, and some wobble along the way.

"Quantum systems can do strange things," Lee says. "If we are to truly understand them, we need to make our theory stranger, too."

The road from quantum mechanics to gravity has long been unpassable. Lee hopes his strange and wobbly quantum map will help physicists at last find their way.

Story Source: The above story is based on materials provided by Perimeter Institute for Theoretical Physics. Note: Materials may be edited for content and length.
Cite This Page: MLA APA Chicago
Perimeter Institute for Theoretical Physics. “Mapping the road to quantum gravity.” ScienceDaily. ScienceDaily, 23 April 2014. .

Source: http://www.sciencedaily.com/releases/2014/04/140423150939.htm

from-dust-of-stars: Freaking interesting!

Mapping the road to quantum gravity. Date: April 23, 2014

Source: Perimeter Institute for Theoretical Physics

Summary: The road uniting quantum field theory and general relativity — the two great theories of modern physics — has been impassable for 80 years. Could a tool from condensed matter physics finally help map the way?

Perimeter Associate Faculty member Sung-Sik Lee is a condensed matter physicist — but he has his eye on quantum gravity.

Lee lays out the problem: “Physics has one theory to describe how planets orbit the sun and another to describe how electrons ‘orbit’ an atomic nucleus. Both theories — gravity as described by Einstein’s general relativity and quantum field theory — are great triumphs. Both are well-tested and powerful. The trouble is, we can’t use both at once.”
Relativity says that spacetime is smooth, and only big things can warp it, in ways that are exactly known. Quantum theory says that the smallest parts of the universe are constantly fluctuating and dramatically uncertain. How can something be both smooth and fluctuating, both exact and uncertain? How, in other words, can we make a quantum theory of gravity?

Physicists simply don’t know. Researchers in both string theory and loop quantum gravity have made progress, but a fully functional unified theory has remained out of reach for more than 80 years.

Enter — of all things — condensed matter physics.

Introducing the renormalization group

As far as the condensed matter physicists are concerned, it’s all about scale.
In all of physics, but particularly in condensed matter, our descriptions of physical systems depend on the scale at which we look at them. For instance, if you wanted to know how your tea would spread across the table if you spilled it, you would describe the puddle with hydrodynamics, and completely ignore the fact that the tea actually consists of single molecules and has a complex microscopic structure. But if you wanted to know details about how a very small drop behaved, you would have to change the description to one that takes the microscopic structure into account.
Condensed matter physicists have developed a powerful suite of mathematical tools for “flowing” a theory at one scale into a theory at a different scale. These tools are collectively known as the renormalization group, or RG.

RG tools allow physicists to take what they know about tea molecules and move seamlessly to a description of a spreading puddle. Like the zoom on a camera, the RG changes the distance scale. It’s perhaps simplistic, but nonetheless true, that distance scales are exactly what separates quantum theory from gravitational theory — one is the physics of the small and one is the physics of the large. Could the renormalization group be the tool that finally unites them?

Maybe. A growing body of researchers, from around the world, is trying to find out. Lee wants to use the RG to better understand the relationship between quantum theory and gravity. Specifically, he wants to make a constructive proof of the AdS/CFT correspondence.

Introducing the AdS/CFT conjecture

At Perimeter and places like it, the phrase “AdS/CFT correspondence” comes up a lot. If it’s always sounded like Greek to you, here’s some background.

AdS is short for anti-de Sitter space. When we say “space” in this case, we mean not the cosmic emptiness of outer space, but space in the mathematical sense — space as geometry. If you imagine drawing a triangle on a piece of paper and another on the surface of a sphere, you might intuit that the rules of geometry depend on the space you’re dealing with. Space as a piece of paper is technically called Euclidean space. Space as the surface of a sphere is technically called elliptical space.

Anti-de Sitter space is elliptical space that obeys the tenets of special relativity — elliptical space that can stretch or contract in extreme circumstances. When physicists say that gravity bends space like a bowling ball on a rubber sheet, anti-de Sitter space is probably the space they have in mind. Thus, the “AdS” part of AdS/CFT refers to a particular description of gravity.

CFT, meanwhile, is short for conformal field theory. Field theories are the language of quantum mechanics. They describe how a field — an electrical field, for example — might change over space and time. Conformal field theories are a subclass of field theories where certain properties of the theory don’t change when scale is changed.
The AdS/CFT correspondence states that for every conformal field theory, there is a corresponding theory of gravity with one more dimension. A two-dimensional CFT would correspond to a three-dimensional theory of gravity, for instance. The two theories look very different, but the AdS/CFT correspondence says that, mathematically, they are identical.

Using the renormalization group to prove the AdS/CFT conjecture
Proposed by Juan Maldecena in 1997, the AdS/CFT correspondence — which is also known as the Maldecena duality or the gauge/gravity duality — has been hugely fruitful. There were intractable problems in field theory that could suddenly be solved in AdS, and deep questions about gravity that could suddenly be addressed via well-explored field theories. But despite its success, AdS/CFT remains a conjecture: it’s never been proved.

"There is a lot of evidence for the conjecture, but there’s no proof," says Lee, who is jointly appointed to Perimeter and to McMaster University. "We know for sure that it works in some special cases. We believe that it applies more generally in other cases, but we don’t know how to make the connection."

What’s needed, Lee says, is constructive proof. That is, he’s not satisfied with knowing that A equals B — he wants to map the path between A and B. That path could then be followed from A’ to B’, from A* to B* — from field theory to gravity. Lee hopes the renormalization group can be that path.

The idea that RG is behind the AdS/CFT correspondence is not new. The AdS/CFT conjecture maps an N dimensional field theory into a N+1 dimensional theory of gravity. The extra dimension is widely interpreted as a length scale (for reasons not discussed here). Since moving theories from one length scale to another is exactly what the renormalization group is for, many experts believe that RG will be key to any proof of the AdS/CFT conjecture.

But there’s still a problem.

Toward a quantum renormalization group

"The problem with the renormalization group is that it predicts things in a way that is deterministic and classical," Lee says. For example, consider one of basic things physicists need to compute: the coupling constant, which predicts the strength of the force between two objects. "Say I have a coupling constant and it has value X at one scale. If I double the length scale, the renormalization group will tell me exactly what the new coupling constant will be."

That sounds like the good news, but it’s actually the bad news. “We are talking about quantum gravity,” says Lee. “Coupling constants will not be exactly known. They will be quantum and dynamical.”

To address this, Lee is working on an extension of the renormalization group which he calls the quantum renormalization group. Whereas traditional RG makes the coupling constants “flow” along a smooth and deterministic path from one exact value to another, Lee’s quantum RG will have built in uncertainty about the start and end points of that path, and some wobble along the way.

"Quantum systems can do strange things," Lee says. "If we are to truly understand them, we need to make our theory stranger, too."

The road from quantum mechanics to gravity has long been unpassable. Lee hopes his strange and wobbly quantum map will help physicists at last find their way.

Story Source: The above story is based on materials provided by Perimeter Institute for Theoretical Physics. Note: Materials may be edited for content and length.
Cite This Page: MLA APA Chicago
Perimeter Institute for Theoretical Physics. “Mapping the road to quantum gravity.” ScienceDaily. ScienceDaily, 23 April 2014. .

Source: http://www.sciencedaily.com/releases/2014/04/140423150939.htm

from-dust-of-stars: Damn fascinating look into our chromosomes and their roles. Damn fascinating.

Repreive For Men: Y Chromosome Is Not Vanishing

Alarming shrinkage has stopped, researchers say, because the Y is a bastion of elite genes that play vital roles throughout the body.

Apr 23, 2014 |By Josh Fischman

Pic: While most human chromosomes are equally paired, the male Y chromosome (bottom right) comes up short when compared to its partner, the female X. 
Credit: U.S. National Library of Medicine

The Y chromosome is definitely the runt of our chromosome litter. Among our 23 pairs of these precious genetic bundles, pairs one through 22 are basically equal in size. But the Y—which holds genes that determine whether a mammal will be a male—is paired with the much larger X chromosome, and pales in size by comparison. Indeed the Y has only 19 of the approximately 600 genes it once shared with the X, 200 to 300 million years ago.
But the decline and fall of the Y has stopped, according to new research published in the April 24 issue of the journal Nature. The Y has been stable for the past 25 million years, scientists say. And a major reason is that many of its remaining genes are crucial to the survival of all humans, going far beyond sex determination. There are genes that affect protein synthesis, how active a gene is, and others that splice RNA segments together. They are found in the heart, the blood, the lungs, and other tissues throughout the body. “These are powerful players in the central command room of cells,” says David Page, a biologist and director of the Whitehead Institute of Biomedical Research at M.I.T. He is one of the authors of the new paper, and says it “puts this notion of the ‘rotting Y’ to rest.”
While other scientists agree that Page’s team is making the Y look rather robust, one of the proponents of the “rotting Y” idea isn’t convinced. The past several million years may simply be a lull in a long-term trend of Y degradation, says Jennifer Graves, a geneticist at the Australian National University in Canberra. “At least two rodent groups have managed to dispense with it” altogether, she says.
The Y chromosome began losing respect in the late 1950s. Geneticist Curt Stern, at the time the president of the American Society of Human Genetics, gave an address noting that very few expressed genes actually resided on the Y. In 2002, Graves and another scientist noted in a paper in Nature that the Y had been diminishing in size from early mammal lineages through primates, and predicted the male chromosome would be extinct in 10 million years. That led to a lot of people wondering whether males would go with it.
Page and his colleagues, led by Daniel Winston Bellott, a research scientist in his lab, set out to test this idea by examining the evolutionary history of the Y. They compared complete sequences of the DNA on the chromosome in eight mammal species. They started with species that appear early in the fossil record, including opossums, bulls, rats and mice, and went on to species that appeared relatively recently, including rhesus macaque monkeys, chimpanzees and humans.
The comparison revealed there was indeed what Page calls “a calamitous loss of genes” from the Y hundreds of millions of years ago. But about 25 million years ago, when monkeys split off from chimps, who then split off from the human lineage about 7 million years ago, the attrition stopped. “We were actually brought up short by how stable the Y has been during the most recent 25 million years,” Page says.
That stability, he argues, comes from a vital core of about 12 genes on the Y that have nothing to do with male sex determination, sperm or male sex organ development. Instead, these genes ensconced on the Y are expressed in other tissues like heart cells and blood cells. They are responsible for vital cellular functions, like protein synthesis or regulating the transcription of other genes. That means the Y is important to the whole organism’s survival, he says, and so survival of these genes would be favored by evolution.
Andrew Clark, a geneticist at Cornell University, agrees that once these core genes had “run a gauntlet” that stripped the Y of less-essential pieces of DNA, they enjoyed remarkable stability.
Graves, the Australian geneticist, is not so sanguine. “Y degradation is clearly not a linear process,” she points out. “The last stages of decay are likely to be subject to great fluctuations.” In her view, the stability may be temporary. She says that two species of spiny rats in Japan have lost the mammalian Y chromosome completely, shifting many genes to other chromosomes. Two mole vole species, she adds, have lost some Y genes completely, probably using other genes to pick up their functions. “Although rodents seem to be ahead of primates in experimenting with bizarre new sex chromosome systems, we should not be complacent,” she concludes.
Page responds that he sees stability of these core Y genes in so many species that further losses appear unlikely. “It could happen, but I just don’t see it,” he says.
The persistent Y and its store of widespread regulatory genes brings up another issue for biologists, Page says: the cells of men and women could be biochemically different. Men with their Y-related genes will have slightly different cells than women, who have two X chromosomes, and that goes above and beyond the differences related to sex determination. When biologists experiment with cell lines, they typically don’t note whether the cells originally came from a male or a female. “We’ve been operating with a unisex model for a long time,” Page says. And it may not be valid. An experiment on an XX cell line may not have the same result as the same experiment run on an XY cell line.
Why this matters, Page says, is because some diseases, like autoimmune illnesses, appear to affect women to a greater degree, while other problems, like autism-spectrum disorders, affect more men. But biologists trying to untangle these mysteries on a cellular level have been, by and large, blind to subtle biochemical differences—because they are not comparing male and female cell lines—that could affect their results. It is time, Page says, to take those blinders off.

Source: http://www.scientificamerican.com/article/repreive-for-men-y-chromosome-is-not-vanishing/

from-dust-of-stars: Damn fascinating look into our chromosomes and their roles. Damn fascinating.

Repreive For Men: Y Chromosome Is Not Vanishing

Alarming shrinkage has stopped, researchers say, because the Y is a bastion of elite genes that play vital roles throughout the body.

Apr 23, 2014 |By Josh Fischman

Pic: While most human chromosomes are equally paired, the male Y chromosome (bottom right) comes up short when compared to its partner, the female X.
Credit: U.S. National Library of Medicine

The Y chromosome is definitely the runt of our chromosome litter. Among our 23 pairs of these precious genetic bundles, pairs one through 22 are basically equal in size. But the Y—which holds genes that determine whether a mammal will be a male—is paired with the much larger X chromosome, and pales in size by comparison. Indeed the Y has only 19 of the approximately 600 genes it once shared with the X, 200 to 300 million years ago.

But the decline and fall of the Y has stopped, according to new research published in the April 24 issue of the journal Nature. The Y has been stable for the past 25 million years, scientists say. And a major reason is that many of its remaining genes are crucial to the survival of all humans, going far beyond sex determination. There are genes that affect protein synthesis, how active a gene is, and others that splice RNA segments together. They are found in the heart, the blood, the lungs, and other tissues throughout the body. “These are powerful players in the central command room of cells,” says David Page, a biologist and director of the Whitehead Institute of Biomedical Research at M.I.T. He is one of the authors of the new paper, and says it “puts this notion of the ‘rotting Y’ to rest.”

While other scientists agree that Page’s team is making the Y look rather robust, one of the proponents of the “rotting Y” idea isn’t convinced. The past several million years may simply be a lull in a long-term trend of Y degradation, says Jennifer Graves, a geneticist at the Australian National University in Canberra. “At least two rodent groups have managed to dispense with it” altogether, she says.

The Y chromosome began losing respect in the late 1950s. Geneticist Curt Stern, at the time the president of the American Society of Human Genetics, gave an address noting that very few expressed genes actually resided on the Y. In 2002, Graves and another scientist noted in a paper in Nature that the Y had been diminishing in size from early mammal lineages through primates, and predicted the male chromosome would be extinct in 10 million years. That led to a lot of people wondering whether males would go with it.

Page and his colleagues, led by Daniel Winston Bellott, a research scientist in his lab, set out to test this idea by examining the evolutionary history of the Y. They compared complete sequences of the DNA on the chromosome in eight mammal species. They started with species that appear early in the fossil record, including opossums, bulls, rats and mice, and went on to species that appeared relatively recently, including rhesus macaque monkeys, chimpanzees and humans.

The comparison revealed there was indeed what Page calls “a calamitous loss of genes” from the Y hundreds of millions of years ago. But about 25 million years ago, when monkeys split off from chimps, who then split off from the human lineage about 7 million years ago, the attrition stopped. “We were actually brought up short by how stable the Y has been during the most recent 25 million years,” Page says.

That stability, he argues, comes from a vital core of about 12 genes on the Y that have nothing to do with male sex determination, sperm or male sex organ development. Instead, these genes ensconced on the Y are expressed in other tissues like heart cells and blood cells. They are responsible for vital cellular functions, like protein synthesis or regulating the transcription of other genes. That means the Y is important to the whole organism’s survival, he says, and so survival of these genes would be favored by evolution.

Andrew Clark, a geneticist at Cornell University, agrees that once these core genes had “run a gauntlet” that stripped the Y of less-essential pieces of DNA, they enjoyed remarkable stability.

Graves, the Australian geneticist, is not so sanguine. “Y degradation is clearly not a linear process,” she points out. “The last stages of decay are likely to be subject to great fluctuations.” In her view, the stability may be temporary. She says that two species of spiny rats in Japan have lost the mammalian Y chromosome completely, shifting many genes to other chromosomes. Two mole vole species, she adds, have lost some Y genes completely, probably using other genes to pick up their functions. “Although rodents seem to be ahead of primates in experimenting with bizarre new sex chromosome systems, we should not be complacent,” she concludes.

Page responds that he sees stability of these core Y genes in so many species that further losses appear unlikely. “It could happen, but I just don’t see it,” he says.

The persistent Y and its store of widespread regulatory genes brings up another issue for biologists, Page says: the cells of men and women could be biochemically different. Men with their Y-related genes will have slightly different cells than women, who have two X chromosomes, and that goes above and beyond the differences related to sex determination. When biologists experiment with cell lines, they typically don’t note whether the cells originally came from a male or a female. “We’ve been operating with a unisex model for a long time,” Page says. And it may not be valid. An experiment on an XX cell line may not have the same result as the same experiment run on an XY cell line.

Why this matters, Page says, is because some diseases, like autoimmune illnesses, appear to affect women to a greater degree, while other problems, like autism-spectrum disorders, affect more men. But biologists trying to untangle these mysteries on a cellular level have been, by and large, blind to subtle biochemical differences—because they are not comparing male and female cell lines—that could affect their results. It is time, Page says, to take those blinders off.

Source: http://www.scientificamerican.com/article/repreive-for-men-y-chromosome-is-not-vanishing/

justtellmeyoucannotsleep:

discard-and-discover:

well that escalated at a perfectly acceptable speed. 

from-dust-of-stars: Very smooth moves

(Source: stewarter)

from-dust-of-stars: Love this!

(Source: weheartit.com)

bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home
Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.
(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous

bobbycaputo:

On Earth Day, These Photos Remind Us Just How Little We Know Of The Planet We Call Home

Happy Earth Day! Every year on April 22, the world celebrates this amazingly diverse planet we call home, focusing on ways to protect it from the often destructive practices of its human inhabitants. While many of these efforts focus on the conservation of Earth’s most fragile habitats, we frequently forget just how extreme and alien-like our own planet can be. The photos below showcase Earth’s unbelievably varying landscapes and remind us that we often live our lives confined only to a minuscule part of this amazing planet.

(Continue Reading)

from-dust-of-stars: Beautiful Earth for Earth day! Our planet is so gorgeous

from-dust-of-stars: Freaking happy Earth day! Celebrate with some of our great mysteries of our mother planet.

Happy Earth Day! The 8 Biggest Mysteries of Our Planet
By Becky Oskin, Senior Writer   |   April 22, 2014 11:40am ET

Pic: An image of the Earth taken by the Russian weather satellite Elektro-L No.1. Credit: NTsOMZ

When the first Earth Day was held in 1970, geologists were still putting the finishing touches on plate tectonics, the model that explains how the Earth’s surface takes shape. More than 40 years later, many riddles still remain when it comes to our planet.

For instance, dozens of spacecraft have mapped the surface of Mars more accurately than Earth’s ocean depths. For today’s Earth day, here are some of Earth’s biggest unsolved mysteries.

1. Why are we all wet?

Scientists think Earth was a dry rock after it coalesced 4.5 billion years ago. So where did this essential chemical, H2O, come from? Perhaps an interstellar delivery system, in the form of massive impacts about 4 billion years ago. Pummeled by icy asteroids, the Earth could have replenished its water reservoirs during the period, called the Late Heavy Bombardment. But the beginnings of Earth’s water are shrouded in mystery because so little rock evidence remains from this time period. [50 Amazing Facts About Planet Earth]

2. What’s down there in the core?

The stuff of legend and lore, Earth’s core has long fascinated writers as well as scientists. For a while, the composition of Earth’s unreachable core was a solved mystery … at least in the 1940s. With meteorites as proxy, scientists gauged the planet’s original balance of essential minerals, and noted which were missing. The iron and nickel absent in Earth’s crust must be in the core, they surmised. But gravity measurements in the 1950s revealed those estimates were incorrect. The core was too light.

Today, researchers continue to guess at which elements account for the density deficit beneath our feet. They’re also puzzled by the periodic reversals in Earth’s magnetic field, which is generated by the outer core’s flowing liquid iron.

This artist’s conception of a planetary smashup whose debris was spotted by NASA’s Spitzer Space Telescope in 2009 gives an impression of the carnage that would have been wrecked when a similar impact created Earth’s moon. Image released Oct. 17, 2012.

3. How did the moon get here?

Did a titanic collision between the Earth and a Mars-size protoplanet form the moon? There’s no universal consensus on this giant impactor theory, because some details don’t pan out. For example, the chemical composition of both rocky bodies matches so closely it suggests the moon was born from Earth, not a separate impactor. But a fast-spinning young Earth could have flung off enough molten rock during impact to form a chemically similar moon, other models suggest. And is there a relationship between these events and the rise of life on Earth, wondered Kevin McKeegan, a geochemist at the University of California, Los Angeles. “These are important planetary issues as we consider the possible histories of Earth-like exoplanets in the habitable zone,” McKeegan said. 

4. Where did life come from?

Was life brewed on Earth or sparked in interstellar space and delivered here on meteorites? The most basic life components, such as amino acids and vitamins, have been found on ice grains inside asteroids and in the most extreme environments on Earth. Figuring out how these parts combined to form the first life is one of biology’s biggest hurdles. And no direct fossil traces of Earth’s first inhabitants — which were probably primitive, rock-chewing bacteria — have yet been found. [7 Theories on the Origin of Life]

5. Where did all the oxygen come from?

We owe our existence to cyanobacteria, microscopic creatures that helped to radically transform Earth’s atmosphere. They pumped out oxygen as waste, and filled the skies with oxygen for the first time about 2.4 billion years ago. But rocks reveal oxygen levels cruised up and down like a roller coaster for 3 billion years, until they stabilized around the Cambrian Period about 541 million years ago. So did bacteria spike the air, or was there another contributing factor? Understanding the shift to an oxygen-rich Earth is a key factor in decoding the history of life on our planet.

Arthropods from the Burgess shale, such as the trilobite Olenoides and a chelicerate called Sidneyia, exploded in morphological diversity following the so-called Cambrian Explosion.

6. What caused the Cambrian explosion?

The appearance of complex life in the Cambrian, after 4 billion years of Earth history, marks a unique turning point, said Donna Whitney, a geologist at the University of Minnesota. Suddenly there were animals with brains and blood vessels, eyes and hearts, all evolving more quickly than during any other planetary era known today. A jump in oxygen levels just before this Cambrian explosion has been offered as explanation, but other factors could explain the mysterious rise of the animals, such as the arms race between predator and prey. 

7. When did plate tectonics start?

Thin plates of hardened crust knocking about Earth’s surface make for beautiful mountain sunsets and violent volcanic eruptions. Yet geologists still don’t know when the plate tectonics engine revved up. Most of the evidence has been destroyed. Just a handful of tiny mineral grains called zircons survive from 4.4 billion years ago, and they tell scientists the first continental-like rocks already existed. But the evidence for early plate tectonics is controversial. And geologists still wonder how continental crust forms, said G. Lang Farmer, a geochemist at the University of Colorado, Boulder. “It’s amazing to me that these fundamental aspects of how Earth works remain so enigmatic,” Farmer said.

8. Will we ever predict earthquakes?

At best, statistical models can tease out a forecast of future earthquake probability, similar to weather experts who warn of coming rain. But that hasn’t kept people from trying to predict when the next one will hit — with no success. Even the biggest experiment failed by 12 years, when geologists predicted an earthquake at Parkfield, Calif., by 1994, and set up instruments to catch the coming temblor. The actual quake hit in 2004. One of the biggest hurdles is that geologists still don’t understand why earthquakes start and stop. But there have been advances in predicting aftershocks and manmade earthquakes, such as those linked to wastewater injection wells (as used in fracking).

Email Becky Oskin or follow her @beckyoskin. Follow us @livescience, Facebook & Google+. Original article on Live Science.

Source: http://www.livescience.com/45015-earth-biggest-unsolved-mysteries.html?cmpid=514645

from-dust-of-stars: Freaking happy Earth day! Celebrate with some of our great mysteries of our mother planet.

Happy Earth Day! The 8 Biggest Mysteries of Our Planet
By Becky Oskin, Senior Writer | April 22, 2014 11:40am ET

Pic: An image of the Earth taken by the Russian weather satellite Elektro-L No.1. Credit: NTsOMZ

When the first Earth Day was held in 1970, geologists were still putting the finishing touches on plate tectonics, the model that explains how the Earth’s surface takes shape. More than 40 years later, many riddles still remain when it comes to our planet.

For instance, dozens of spacecraft have mapped the surface of Mars more accurately than Earth’s ocean depths. For today’s Earth day, here are some of Earth’s biggest unsolved mysteries.

1. Why are we all wet?

Scientists think Earth was a dry rock after it coalesced 4.5 billion years ago. So where did this essential chemical, H2O, come from? Perhaps an interstellar delivery system, in the form of massive impacts about 4 billion years ago. Pummeled by icy asteroids, the Earth could have replenished its water reservoirs during the period, called the Late Heavy Bombardment. But the beginnings of Earth’s water are shrouded in mystery because so little rock evidence remains from this time period. [50 Amazing Facts About Planet Earth]

2. What’s down there in the core?

The stuff of legend and lore, Earth’s core has long fascinated writers as well as scientists. For a while, the composition of Earth’s unreachable core was a solved mystery … at least in the 1940s. With meteorites as proxy, scientists gauged the planet’s original balance of essential minerals, and noted which were missing. The iron and nickel absent in Earth’s crust must be in the core, they surmised. But gravity measurements in the 1950s revealed those estimates were incorrect. The core was too light.

Today, researchers continue to guess at which elements account for the density deficit beneath our feet. They’re also puzzled by the periodic reversals in Earth’s magnetic field, which is generated by the outer core’s flowing liquid iron.

This artist’s conception of a planetary smashup whose debris was spotted by NASA’s Spitzer Space Telescope in 2009 gives an impression of the carnage that would have been wrecked when a similar impact created Earth’s moon. Image released Oct. 17, 2012.

3. How did the moon get here?

Did a titanic collision between the Earth and a Mars-size protoplanet form the moon? There’s no universal consensus on this giant impactor theory, because some details don’t pan out. For example, the chemical composition of both rocky bodies matches so closely it suggests the moon was born from Earth, not a separate impactor. But a fast-spinning young Earth could have flung off enough molten rock during impact to form a chemically similar moon, other models suggest. And is there a relationship between these events and the rise of life on Earth, wondered Kevin McKeegan, a geochemist at the University of California, Los Angeles. “These are important planetary issues as we consider the possible histories of Earth-like exoplanets in the habitable zone,” McKeegan said.

4. Where did life come from?

Was life brewed on Earth or sparked in interstellar space and delivered here on meteorites? The most basic life components, such as amino acids and vitamins, have been found on ice grains inside asteroids and in the most extreme environments on Earth. Figuring out how these parts combined to form the first life is one of biology’s biggest hurdles. And no direct fossil traces of Earth’s first inhabitants — which were probably primitive, rock-chewing bacteria — have yet been found. [7 Theories on the Origin of Life]

5. Where did all the oxygen come from?

We owe our existence to cyanobacteria, microscopic creatures that helped to radically transform Earth’s atmosphere. They pumped out oxygen as waste, and filled the skies with oxygen for the first time about 2.4 billion years ago. But rocks reveal oxygen levels cruised up and down like a roller coaster for 3 billion years, until they stabilized around the Cambrian Period about 541 million years ago. So did bacteria spike the air, or was there another contributing factor? Understanding the shift to an oxygen-rich Earth is a key factor in decoding the history of life on our planet.

Arthropods from the Burgess shale, such as the trilobite Olenoides and a chelicerate called Sidneyia, exploded in morphological diversity following the so-called Cambrian Explosion.

6. What caused the Cambrian explosion?

The appearance of complex life in the Cambrian, after 4 billion years of Earth history, marks a unique turning point, said Donna Whitney, a geologist at the University of Minnesota. Suddenly there were animals with brains and blood vessels, eyes and hearts, all evolving more quickly than during any other planetary era known today. A jump in oxygen levels just before this Cambrian explosion has been offered as explanation, but other factors could explain the mysterious rise of the animals, such as the arms race between predator and prey.

7. When did plate tectonics start?

Thin plates of hardened crust knocking about Earth’s surface make for beautiful mountain sunsets and violent volcanic eruptions. Yet geologists still don’t know when the plate tectonics engine revved up. Most of the evidence has been destroyed. Just a handful of tiny mineral grains called zircons survive from 4.4 billion years ago, and they tell scientists the first continental-like rocks already existed. But the evidence for early plate tectonics is controversial. And geologists still wonder how continental crust forms, said G. Lang Farmer, a geochemist at the University of Colorado, Boulder. “It’s amazing to me that these fundamental aspects of how Earth works remain so enigmatic,” Farmer said.

8. Will we ever predict earthquakes?

At best, statistical models can tease out a forecast of future earthquake probability, similar to weather experts who warn of coming rain. But that hasn’t kept people from trying to predict when the next one will hit — with no success. Even the biggest experiment failed by 12 years, when geologists predicted an earthquake at Parkfield, Calif., by 1994, and set up instruments to catch the coming temblor. The actual quake hit in 2004. One of the biggest hurdles is that geologists still don’t understand why earthquakes start and stop. But there have been advances in predicting aftershocks and manmade earthquakes, such as those linked to wastewater injection wells (as used in fracking).

Email Becky Oskin or follow her @beckyoskin. Follow us @livescience, Facebook & Google+. Original article on Live Science.

Source: http://www.livescience.com/45015-earth-biggest-unsolved-mysteries.html?cmpid=514645

getoffmybloghoe:

when you lose your phone in the blanket and you just image

from-dust-of-stars: LMFAO… So true

bc-of-light-on-my-heart:

oh my, I have a lot of respect for her

from-dust-of-stars: Sandra, your are just so awesome.
PS: I’m single *wink* ;)

(Source: olivesnooks)

mulheresfatais:

http://mulheresfatais.tumblr.com/


from-dust-of-stars: Mmm, beautiful lovemaking. Damn!

mulheresfatais:

http://mulheresfatais.tumblr.com/

from-dust-of-stars: Mmm, beautiful lovemaking. Damn!

(Source: yourblowjobprincess)