Science Simplified!

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Comment by Dr. Krishna Kumari Challa on January 27, 2014 at 8:45am

Stephen Hawking, famous theoretical physicist and bestselling author, has created a flutter in the scientific world by proposing that what science has theorized about black holes may be wrong.

In a paper which is yet to be peer reviewed, Hawking suggests that black holes may not have an event horizon, the boundary that prevents any light or matter from escaping the clutches of its monstrous gravity, the scientific journal Nature reported today. What may exist is an "apparent horizon" which is much less tyrannical and only temporarily prevents matter and energy from escaping.

Hawking is considered as one of the world's foremost cosmologists and it was he who did most of the spadework for the theory of black holes in the 1970s. Later he proposed that 'event horizons' are not as impermeable as theorized and some matter or energy does manage to escape from them. This was dubbed Hawking Radiation.

According to Einstein's theory, a black hole is an entity in which matter has collapsed to a single point creating gigantic gravitational force, and trapping all energy or matter from ever escaping its clutches. Since light or any radiation cannot escape from a black hole, humans or their instruments can never directly 'see' a black hole although its existence is inferred from other symptoms nearby like high energy radiation emitted by matter just before falling into the black hole.

Quantum theory however allows energy to escape the black hole. This paradox - the variance between two theories that are true in their own conditions but fail in extreme conditions like the black hole - has troubled scientists for long. The only way out would be for some theory that could successfully merge gravity with the quantum mechanics.

Hawking's latest paper, titled "Information Preservation and Weather Forecasting for Black Holes" is available on the arXiv preprint server.

According to Nature, Hawking's paper is an "attempt to solve the so-called black-hole firewall paradox, which has been vexing physicists for almost two years". This paradox works like this: Einstein's theory predicts that if a space traveler were to fall into a black hole, he or she would just shoot through the event horizon with nary a ruffle and accelerate towards the black hole's infinitely dense core, all the time getting stretched longer and longer like a noodle. But quantum mechanics predicts that the event horizon should be a highly energetic region - a 'firewall' as Nature puts it - and the space traveler would be burnt to a cinder instantaneously.

Hawking's paper is the solution - a third way out of this paradox. He does away with the event horizon, saving both general relativity and quantum mechanics. Hawking's new idea is the 'apparent horizon' where energy like light rays speeding away from the black hole will be suspended. In some cases the event horizon may coincide with the apparent horizon, in others it may shrink below the apparent one.

This idea upturns the whole black hole mystique. "The absence of event horizons mean that there are no black holes — in the sense of regimes from which light can't escape to infinity," Hawking writes in the paper, according to Nature.

Comment by Dr. Krishna Kumari Challa on January 27, 2014 at 8:45am

Stephen Hawking now says there are no black holes - at least not in the way we perceive them !
Stephen Hawking has produced a "mind-bending" new theory that argues black holes do not actually exist — at least not in the way we currently perceive them. Instead, in his paper, Information Preservation and Weather Forecasting for Black Holes, Hawking proposes that black holes can exist without "event horizons" , the invisible cover believed to surround every black hole. During a previous lecture, "Into the Black Hole" , Hawkins described an event horizon as the boundary of a black hole, "where gravity is just strong enough to drag light back, and prevent it escaping" . "Falling through the event horizon, is a bit like going over Niagara Falls in a canoe" , he said. "If you are above the falls, you can get away if you paddle fast enough, but once you are over the edge, you are lost. There's no way back.

"As you get nearer the falls, the current gets faster. This means it pulls harder on the front of the canoe, than the back. There's a danger that the canoe will be pulled apart. It is the same with black holes."

But now, Hawking is proposing "apparent horizons" could exist instead, which would only hold light and information temporarily before releasing them back into space in "garbled form" , Nature has reported.

The internationally-renowned theoretical physicist suggests that quantum mechanics and general relativity remain intact, but black holes do not have an event horizon to catch fire.

His work attempts to address the "black-hole firewall paradox" first discovered by theoretical physicist Joseph Polchinski and his colleagues almost two years ago, when Polchinski and his team began investigating what would happen to an astronaut who fell into a black hole.

They hypothesised that instead of being gradually ripped apart by gravitational forces, the event horizon would be transformed into a "highly energetic region" , and anyone who fell in would hit a wall of fire and burn to death in an instant — violating Albert Einstein's theory of relativity.

In his paper, Hawking writes: "The absence of event horizons means that there are no black holes — in the sense of regimes from which light can't escape to infinity."

He told Nature jour nal: "There is no escape from a black hole in classical theory, but quantum theory, however, "enables energy and information to escape from a black hole."

Don Page, a physicist and expert on black holes at the University of Alberta in Edmonton, Canada told Nature that "the picture Hawking gives sounds pretty reasonable" .

"You could say that it is radical to propose there's no event horizon" , he said. "But these are highly quantum conditions, and there's ambiguity about what space-time even is, let alone whether there is a definite region that can be marked as an event horizon."

Comment by Dr. Krishna Kumari Challa on January 27, 2014 at 8:33am

Childhood Amnesia – At What Age Do We Start Forgetting Childhood Memories?
Memories are the way that infants learn new information, however, few adults can remember events that occurred before the age of three. According to a new study from Emory University psychologists, these early memories fade around age seven in a phenomenon known as “childhood amnesia.”

According to Emory’s Carol Clark, the research team interviewed children about past events in their lives, starting at age three. At ages five, six, seven, eight and nine, different subsets of the total group of children were tested for recall of those same events.

“Our study is the first empirical demonstration of the onset of childhood amnesia,” said Emory psychologist Patricia Bauer. “We actually recorded the memories of children, and then we followed them into the future to track when they forgot these memories.” Bauer collaborated with Marina Larkina, a manager of research projects for Emory’s Department of Psychology.

http://www.redorbit.com/news/science/1113055060/childhood-memories-...

Comment by Dr. Krishna Kumari Challa on January 25, 2014 at 9:48am

Adam’ walked the Earth 209,000 years ago: UK scientists claim the first man lived 9,000 years earlier than previously thought

To calculate age of the Y chromosome, researchers multiplied data on age fathers have their first child with the number of mutations they uncovered
They then divided this figure by the mutation rate of the Y chromosome
Their findings suggest that 'Adam' lived in the same time frame as 'Eve'
Earlier study at Arizona University claimed Y chromosome originated in a different species through interbreeding and dated 'Adam' to be twice as old

STUDY SUGGESTS ADAM AND EVE LIVED IN AFRICA AT THE SAME TIME

Results of a separate study announced in August last year suggest that Adam and Eve lived in Africa at the same time - but probably never met.

It was previously believed that ‘Y-chromosomal Adam’ and ‘Mitochondrial Eve’ - the most recent common ancestors to males and females - lived at completely different times.

But a study of 69 men from around the world found ‘Y-chromosomal Adam’ walked the Earth between 120,000 and 156,000 years ago, much earlier than previously believed.

It places him nearer to Eve who was around 99,000 to 148,000 years ago the analysis found.

The researchers at Stanford University, California, say it is ‘extremely unlikely’ they were exact contemporaries.

Initial estimates for the male MRCA ranged from between 50,000 to 115,000 years ago.

Geneticist Professor Carlos Bustamante, of Stanford University, California, said: 'Previous research has indicated the male most recent common ancestor (MRCA) lived much more recently than the female MRCA. But now our research shows there is no discrepancy.'

http://www.dailymail.co.uk/sciencetech/article-2544731/Adam-walked-...

Comment by Dr. Krishna Kumari Challa on January 25, 2014 at 8:48am

Creating Tastier and Healthier Fruits and Veggies with a Modern Alternative to GMOs
By combining traditional plant breeding with ever-faster genetic sequencing tools, researchers are making fruits and vegetables more flavorful, colorful, shapely and nutritious
http://www.scientificamerican.com/article/creating-tastier-and-heal...

Comment by Dr. Krishna Kumari Challa on January 25, 2014 at 8:33am

Scientific acronyms:
CuNT - unfortunate shorthand for Copper NanoTube
One of the ISS flight controller positions has the following console tools:

APU, BART, HOMER, LISA, MARGE, MAGGIE, MOE, PATI, and DUFFman.

APU: Attitude Planning Utility
BART: Basic Attitude Replication Tool
LISA: Library for ISP, SODF, and Applications
astronomy!

BIGASS: Bright Infrared Galaxy All Sky Survey
FLAMINGOS: FLoridA Multi-object Imaging Near-infrared Grism Observational Spectrometer
GANDALF: Gas AND Absorption Line Fitting algorithm
LUCIFER: LBT near infrared spectroscopic Utility with Camera and Integral Field Unit for Extragalactic Research
WISEASS: Weizmann Institute of Science Experimental Astrophysics Spectroscopy System
https://www.cfa.harvard.edu/~gpetitpas/Links/Astroacro.html
Bra in Quantum Mechanics, used for dual vectors!

Weakly Interacting Massive Particles (WIMPs).

CLARITY -- Clear Lipid-exchanged Anatomically Rigid Imaging Tissue hYdrogel.

TIT - Turbine Inlet Temperature.

GNU. It recursively stands for GNU's Not Unix as it was born in opposition to Unix.
There are many more such recursive acronyms in Computer Science such as PHP (PHP Hypertext Processor), RPM (RPM Package Manager) etc.

 

HERP: Human Exposure Rodent Potency (a measure of toxicity based on animal testing).  Ranking Possible Cancer Hazards from Rodent Carcinogens, Using the ...
DERP: Drug Effectiveness Review Project (a pharmaceutical review program)
Drug Effectiveness Review Project (DERP)

 

Comment by Dr. Krishna Kumari Challa on January 23, 2014 at 6:25am

Plants like animals can learn things!
Researchers in Australia have published evidence that plants can learn and remember just as well as it would be expected of animals.
After publishing a study about plants being able to ‘talk’ using sound, a researcher in Australia has now discovered that they can ‘learn’ as well.

While this may sound stranger than fiction, Dr Monica Gagliano has solid evidence to support her theories, the latest of which is published in Oecologia.

In the new article, Dr Gagliano and her team show that Mimosa pudica plants can learn and remember just as well as it would be expected of animals, but of course, they do it all without a brain.

Using the same experimental framework normally applied to test learnt behavioral responses and trade-offs in animals, they designed their experiments as if Mimosa was indeed an animal.

Dr Gagliano and her colleagues trained Mimosa plants’ short- and long-term memories under both high and low-light environments by repeatedly dropping water on them using a custom-designed apparatus (Mimosa folds its leaves in response to the drop).

In their experiments, Mimosa plants stopped closing their leaves when they learnt that the repeated disturbance had no real damaging consequence. Mimosa plants were able to acquire the learnt behavior in a matter of seconds and as in animals, learning was faster in a less favorable environment (i.e. low light).

Most remarkably, these plants were able to remember what had been learned for several weeks, even after environmental conditions had changed.

Although plants lack brains and neural tissues, they do possess a sophisticated calcium-based signaling network in their cells that is similar to animals’ memory processes.

While the researchers do not yet understand the biological basis for this learning mechanism, their findings may radically change the way we perceive plants and the boundaries between plants and animals. This includes our definition of learning (and hence memory) as a unique property of organisms with functioning nervous systems.
Source:
http://link.springer.com/article/10.1007%2Fs00442-013-2873-7
The nervous system of animals serves the acquisition, memorization and recollection of information. Like animals, plants also acquire a huge amount of information from their environment, yet their capacity to memorize and organize learned behavioral responses has not been demonstrated. In Mimosa pudica—the sensitive plant—the defensive leaf-folding behaviour in response to repeated physical disturbance exhibits clear habituation, suggesting some elementary form of learning. Applying the theory and the analytical methods usually employed in animal learning research, we show that leaf-folding habituation is more pronounced and persistent for plants growing in energetically costly environments. Astonishingly, Mimosa can display the learned response even when left undisturbed in a more favourable environment for a month. This relatively long-lasting learned behavioural change as a result of previous experience matches the persistence of habituation effects observed in many animals.

Comment by Dr. Krishna Kumari Challa on January 23, 2014 at 6:20am

There is no sixth sense!

Yes, without invoking a sixth sense, people can reliably sense when a change had occurred even when they could not see exactly what had changed.

People can reliably sense when a change had occurred even when they could not see exactly what had changed, according to a new study by researchers in Australia.

However, the researchers concluded that this is not due to extrasensory perception (ESP) or having a sixth sense. Rather they do this by picking up cues from more conventional senses such as sight.

Lead researcher Dr Piers Howe said the research is the first to show in a scientific study that people can reliably sense changes that they cannot visually identify.

In the study, published in PLOS ONE, observers were presented with pairs of color photographs, both of the same female. In some cases, her appearance would be different in the two photographs. For example, the individual might have a different hairstyle.

Each photograph was presented for 1.5 seconds with a 1 second break between them. After the last photograph, the observer was asked whether a change had occurred and, if so, identify the change from a list of nine possible changes.

Results showed study participants could generally detect when a change had occurred even when they could not identify exactly what had changed.

For example, they might notice that the two photographs had different amounts of red or green but not be able to use this information to determine that the person had changed the color of their hat. This resulted in the observer “feeling” or “sensing” that a change had occurred without being able to visually identify the change.

According to the researchers, this is evidence that people can receive information through their senses that they are unable to describe verbally. However, people often attribute this “feeling” or “sensing” to an extrasensory ability.

“There is a common belief that observers can experience changes directly with their mind, without needing to rely on the traditional physical senses such as vision, hearing, taste, smell and touch to identify it. This alleged ability is sometimes referred to as a sixth sense or ESP,” said Dr Howe.

“We were able to show that while observers could reliably sense changes that they could not visually identify, this ability was not due to extrasensory perception or a sixth sense.”

Source: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone....

Comment by Dr. Krishna Kumari Challa on January 23, 2014 at 5:57am

Comment by Dr. Krishna Kumari Challa on January 18, 2014 at 8:36am

Researchers Find New Form Of Quantum Matter
http://www.redorbit.com/news/science/1113049585/new-form-of-quantum...

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