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Comment by Dr. Krishna Kumari Challa on May 24, 2014 at 6:10am

Spontaneous creation of the universe from nothing-part 2

According to Heisenberg’s uncertainty principle, quantum fluctuations in the metastable false vacuum – a state absent of space, time or matter – can give rise to virtual particle pairs. Ordinarily these pairs self-annihilate almost instantly, but if these virtual particles separate immediately, they can avoid annihilation, creating a true vacuum bubble. The Wuhan team’s equations show that such a bubble has the potential to expand exponentially, causing a new universe to appear. All of this begins from quantum behavior and leads to the creation of a tremendous amount of matter and energy during the inflation stage. (Note that as stated in this paper, the metastable false vacuum has “neither matter nor space or time,” but is a form of wavefunction referred to as “quantum potential.” While most of us wouldn’t be inclined to call this “nothing,” physicists do refer to it as such.)
This description of exponential growth of a true vacuum bubble corresponds directly to the period of cosmic inflation resulting from the Big Bang. According to this proof, the bubble even stops expanding – or else it may continue to expand at a constant velocity – once it reaches a certain size. Nevertheless, this is a very different version of inflation than those proposed by Guth, Linde and others, in that it doesn’t rely on scalar fields, only quantum effects. Still, this work dovetails well with that of the BICEP2 team, both discoveries having significant implications for our understanding of the universe and our future should they stand up to further inquiry.

This description of exponential growth of a true vacuum bubble corresponds directly to the period of cosmic inflation resulting from the Big Bang. According to this proof, the bubble even stops expanding – or else it may continue to expand at a constant velocity – once it reaches a certain size. Nevertheless, this is a very different version of inflation than those proposed by Guth, Linde and others, in that it doesn’t rely on scalar fields, only quantum effects. Still, this work dovetails well with that of the BICEP2 team, both discoveries having significant implications for our understanding of the universe and our future should they stand up to further inquiry.

Comment by Dr. Krishna Kumari Challa on May 24, 2014 at 6:08am

Spontaneous creation of the universe from nothing-part1
Dongshan He, Dongfeng Gao, Qing-yu Cai
(Submitted on 4 Apr 2014)

An interesting idea is that the universe could be spontaneously created from nothing, but no rigorous proof has been given. In this paper, we present such a proof based on the analytic solutions of the Wheeler-DeWitt equation (WDWE). Explicit solutions of the WDWE for the special operator ordering factor p=-2 (or 4) show that, once a small true vacuum bubble is created by quantum fluctuations of the metastable false vacuum, it can expand exponentially no matter whether the bubble is closed, flat or open. The exponential expansion will end when the bubble becomes large and thus the early universe appears. With the de Broglie-Bohm quantum trajectory theory, we show explicitly that it is the quantum potential that plays the role of the cosmological constant and provides the power for the exponential expansion of the true vacuum bubble. So it is clear that the birth of the early universe completely depends on the quantum nature of the theory.

Comments: The problem of singularity can be avoided naturally as the universe can be spontaneously created from nothing
Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th); Quantum Physics (quant-ph)
Journal reference: Phys. Rev. D 89, 083510 (2014)
DOI: 10.1103/PhysRevD.89.083510
Cite as: arXiv:1404.1207 [gr-qc]
(or arXiv:1404.1207v1 [gr-qc] for this version)
Submission history
From: Qing-Yu Cai [view email]
[v1] Fri, 4 Apr 2014 10:09:09 GMT (9kb)
http://arxiv.org/abs/1404.1207

Comment by Dr. Krishna Kumari Challa on May 23, 2014 at 7:28am

A slow heartbeat in athletes is not so funny
Changes in the ‘funny channel’ of heart’s pacemaker may be behind sinus bradycardia
https://www.sciencenews.org/blog/scicurious/slow-heartbeat-athletes...

Comment by Dr. Krishna Kumari Challa on May 23, 2014 at 6:19am

How Gut Bacteria Help Make Us Fat and Thin
Intestinal bacteria may help determine whether we are lean or obese
Adults who do daily battle with obesity, the main causes of their condition are all too familiar: an unhealthy diet, a sedentary lifestyle and perhaps some unlucky genes. In recent years, however, researchers have become increasingly convinced that important hidden players literally lurk in human bowels: billions on billions of gut microbes.

New evidence indicates that gut bacteria alter the way we store fat, how we balance levels of glucose in the blood, and how we respond to hormones that make us feel hungry or full. The wrong mix of microbes, it seems, can help set the stage for obesity and diabetes from the moment of birth.
http://www.scientificamerican.com/article/how-gut-bacteria-help-mak...

Comment by Dr. Krishna Kumari Challa on May 23, 2014 at 6:14am

Comment by Dr. Krishna Kumari Challa on May 23, 2014 at 5:54am

Dustup emerges over gravitational waves discovery

Scrutiny of BICEP2’s evidence of inflation suggests signals could come from Milky Way dust

https://www.sciencenews.org/article/dustup-emerges-over-gravitation...

Backlash to Big Bang Discovery Gathers Steam
Physicists cast doubt on a landmark experiment’s claim to have observed gravity waves from the big bang
http://www.scientificamerican.com/article/backlash-to-big-bang-disc...

Comment by Dr. Krishna Kumari Challa on May 22, 2014 at 7:30am

Scientists Uncover How EBV Hides
A new study has shown that the Epstein-Barr virus flies below the immune system’s radar by restricting the production of the protein EBNA1.
Epstein-Barr virus infects more than 90 percent of the world’s population and is linked to a number of cancers including Burkitt’s lymphoma, nasopharyngeal carcinoma and Hodgkin’s lymphoma. There are currently no vaccines to prevent EBV and other herpes virus-associated cancers.
http://www.nature.com/nchembio/journal/v10/n5/full/nchembio.1479.html

Comment by Dr. Krishna Kumari Challa on May 22, 2014 at 7:28am

Training The Immune System To Target Brain Cancer
By exploiting the fact that many brain tumors harbor cytomegalovirus, scientists have used the patient’s immune system to target brain cancer.
Scientists have made headway in the treatment of the aggressive brain cancer glioblastoma multiforme (GBM) with the use of immunotherapy. This study was published in the journal Cancer Research.
Researchers developed a technique to modify the patients’ T-cells in the laboratory, effectively “training” them to attack the virus, and then returned them to the patient’s body while keeping them on chemotherapy. It is thought that the killer T-cells destroy the cancer cells along with the virus-infected cells.
http://cancerres.aacrjournals.org/content/early/2014/05/07/0008-547...

Comment by Dr. Krishna Kumari Challa on May 22, 2014 at 7:16am

Biomechanics of ants: New Research: The neck joints of ants could withstand loads of about 5,000 times the ant's body weight, and that the ant's neck-joint structure produced the highest strength when its head was aligned straight, as opposed to turned to either side.
"The design and structure of this interface is critical for the performance of the neck joint. The unique interface between hard and soft materials likely strengthens the adhesion and may be a key structural design feature that enables the large load capacity of the neck joint."
The simulations confirmed the joint's directional strength and, consistent with the experimental results, indicated that the critical point for failure of the neck joint is at the neck-to-head transition, where soft membrane meets the hard exoskeleton. The neck joint [of the ant] is a complex and highly integrated mechanical system. Efforts to understand the structure-function relationship in this system will contribute to the understanding of the design paradigms for optimized exoskeleton mechanisms.
'' Scientists study biomechanics behind amazing ant strength''
https://www.osc.edu/press/scientists_study_biomechanics_behind_amaz...

Comment by Dr. Krishna Kumari Challa on May 21, 2014 at 6:45am

Diverse gene pool critical for tigers' survival: Stanford scholars
Increasing tigers' genetic diversity – via interbreeding and other methods – and not just their population numbers may be the best solution to saving this endangered species, according to Stanford research.
a new research by Stanford scholars shows that increasing genetic diversity among the 3,000 or so tigers left on the planet is the key to their survival as a species. That research shows that the more gene flow there is among tiger populations, the more genetic diversity is maintained and the higher the chances of species survival become. In fact, it might be possible to maintain tiger populations that preserve about 90 percent of genetic diversity. The research focused on the Indian subcontinent, home to about 65 percent of the world's wild tigers. The scientists found that as populations become more fragmented and the pools of each tiger subspecies shrink, so does genetic diversity. This loss of diversity can lead to lower reproduction rates, faster spread of disease and more cardiac defects, among other problems."Genetic diversity is the basis for adaptation."
The results showed that for tiger populations to maintain their current genetic diversity 150 years from now, the tiger population would have to expand to about 98,000 individuals if gene flow across species were delayed 25 years. By comparison, the population would need to grow to about 60,000 if gene flow were achieved immediately. Neither of these numbers is realistic, considering the limited size of protected tiger habitat and availability of prey, among other factors, according to the researchers.

"Since genetic variability is the raw material for future evolution, our results suggest that without interbreeding sub-populations of tigers, the genetic future for tigers is not viable," said co-author Uma Ramakrishnan, a former Stanford postdoctoral scholar in biology and current researcher at the National Centre for Biological Sciences in Bangalore, India.

Because migration and interbreeding among subspecies appear to be "much more important" for maintaining genetic diversity than increasing population numbers, the researchers recommend focusing conservation efforts on creating ways for tigers to travel longer distances, such as wildlife corridors, and potentially crossbreeding wild and captive tiger subspecies.

"This is very much counter to the ideas that many managers and countries have now - that tigers in zoos are almost useless and that interbreeding tigers from multiple countries is akin to genetic pollution," said Hadly. "In this case, survival of the species matters more than does survival of the exclusive traits of individual populations," says the report.

Understanding these factors can help decision-makers better address how development affects populations of tigers and other animals, the study noted.

Iconic symbols of power and beauty, wild tigers may roam only in stories someday soon. Their historical range has been reduced by more than 90 percent. But conservation plans that focus only on increasing numbers and preserving distinct subspecies ignore genetic diversity, according to the study. In fact, under that approach, the tiger could vanish entirely.

http://news.stanford.edu/news/2014/april/tigers-genetic-diversity-0...

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