Cientificamente falando...

['Slash]

Ainda não consegui ver nenhuma. Vou tentar hoje, outra vez. :dry:

[Taka]

Agora é muito difícil ver. Já passou o pico de actividade (8-14 Agosto).

['Slash]

Bah. :doubt:

[antifa]

Podes tentar ver porque todas as noites há estrelas cadentes... são é mais raras. No pico de actividade desta chuva das perseiades conseguias ver até 50 ou 60 por hora em locais proprios

[antifa]

Every Black Hole Contains Another Universe?

And our universe may sit in another universe's black hole, equations predict

 

Ker Than

 

for National Geographic News

 

Published April 9, 2010

 

Like part of a cosmic Russian doll, our universe may be nested inside a black hole that is itself part of a larger universe.

 

In turn, all the black holes found so far in our universe—from the microscopic to the supermassive—may be doorways into alternate realities.

 

According to a mind-bending new theory, a black hole is actually a tunnel between universes—a type of wormhole. The matter the black hole attracts doesn't collapse into a single point, as has been predicted, but rather gushes out a "white hole" at the other end of the black one, the theory goes.

 

(Related: "New Proof Unknown 'Structures' Tug at Our Universe.")

 

In a recent paper published in the journal Physics Letters B, Indiana University physicist Nikodem Poplawski presents new mathematical models of the spiraling motion of matter falling into a black hole. His equations suggest such wormholes are viable alternatives to the "space-time singularities" that Albert Einstein predicted to be at the centers of black holes.

 

According to Einstein's equations for general relativity, singularities are created whenever matter in a given region gets too dense, as would happen at the ultradense heart of a black hole.

 

Einstein's theory suggests singularities take up no space, are infinitely dense, and are infinitely hot—a concept supported by numerous lines of indirect evidence but still so outlandish that many scientists find it hard to accept.

 

If Poplawski is correct, they may no longer have to.

 

According to the new equations, the matter black holes absorb and seemingly destroy is actually expelled and becomes the building blocks for galaxies, stars, and planets in another reality.

 

(Related: "Dark Energy's Demise? New Theory Doesn't Use the Force.")

 

Wormholes Solve Big Bang Mystery?

 

The notion of black holes as wormholes could explain certain mysteries in modern cosmology, Poplawski said.

 

For example, the big bang theory says the universe started as a singularity. But scientists have no satisfying explanation for how such a singularity might have formed in the first place.

 

If our universe was birthed by a white hole instead of a singularity, Poplawski said, "it would solve this problem of black hole singularities and also the big bang singularity."

 

Wormholes might also explain gamma ray bursts, the second most powerful explosions in the universe after the big bang.

 

Gamma ray bursts occur at the fringes of the known universe. They appear to be associated with supernovae, or star explosions, in faraway galaxies, but their exact sources are a mystery. (Related: "Gamma-Ray Burst Caused Mass Extinction?")

 

Poplawski proposes that the bursts may be discharges of matter from alternate universes. The matter, he says, might be escaping into our universe through supermassive black holes—wormholes—at the hearts of those galaxies, though it's not clear how that would be possible.

 

"It's kind of a crazy idea, but who knows?" he said. (Related: "Are Wormholes Tunnels for Time Travel?")

 

There is at least one way to test Poplawski's theory: Some of our universe's black holes rotate, and if our universe was born inside a similarly revolving black hole, then our universe should have inherited the parent object's rotation.

 

If future experiments reveal that our universe appears to rotate in a preferred direction, it would be indirect evidence supporting his wormhole theory, Poplawski said.

 

Wormholes Are "Exotic Matter" Makers?

 

The wormhole theory may also help explain why certain features of our universe deviate from what theory predicts, according to physicists.

 

Based on the standard model of physics, after the big bang the curvature of the universe should have increased over time so that now—13.7 billion years later—we should seem to be sitting on the surface of a closed, spherical universe.

 

But observations show the universe appears flat in all directions.

 

What's more, data on light from the very early universe show that everything just after the big bang was a fairly uniform temperature.

 

That would mean that the farthest objects we see on opposite horizons of the universe were once close enough to interact and come to equilibrium, like molecules of gas in a sealed chamber.

 

Again, observations don't match predictions, because the objects farthest from each other in the known universe are so far apart that the time it would take to travel between them at the speed of light exceeds the age of the universe.

 

To explain the discrepancies, astronomers devised the concept of inflation.

 

Inflation states that shortly after the universe was created, it experienced a rapid growth spurt during which space itself expanded at faster-than-light speeds. The expansion stretched the universe from a size smaller than an atom to astronomical proportions in a fraction of a second.

 

The universe therefore appears flat, because the sphere we're sitting on is extremely large from our viewpoint—just as the sphere of Earth seems flat to someone standing in a field.

 

Inflation also explains how objects so far away from each other might have once been close enough to interact.

 

But—assuming inflation is real—astronomers have always been at pains to explain what caused it. That's where the new wormhole theory comes in.

 

According to Poplawski, some theories of inflation say the event was caused by "exotic matter," a theoretical substance that differs from normal matter, in part because it is repelled rather than attracted by gravity.

 

Based on his equations, Poplawski thinks such exotic matter might have been created when some of the first massive stars collapsed and became wormholes.

 

"There may be some relationship between the exotic matter that forms wormholes and the exotic matter that triggered inflation," he said.

 

(Related: "Before the Big Bang: Light Shed on 'Previous Universe.'")

 

Wormhole Equations an "Actual Solution"

 

The new model isn't the first to propose that other universes exist inside black holes. Damien Easson, a theoretical physicist at Arizona State University, has made the speculation in previous studies.

 

"What is new here is an actual wormhole solution in general relativity that acts as the passage from the exterior black hole to the new interior universe," said Easson, who was not involved in the new study.

 

"In our paper, we just speculated that such a solution could exist, but Poplawski has found an actual solution," said Easson, referring to Poplawski's equations.

 

(Related: "Universe 20 Million Years Older Than Thought.")

 

Nevertheless, the idea is still very speculative, Easson said in an email.

 

"Is the idea possible? Yes. Is the scenario likely? I have no idea. But it is certainly an interesting possibility."

 

Future work in quantum gravity—the study of gravity at the subatomic level—could refine the equations and potentially support or disprove Poplawski's theory, Easson said.

 

Wormhole Theory No Breakthrough

 

Overall, the wormhole theory is interesting, but not a breakthrough in explaining the origins of our universe, said Andreas Albrecht, a physicist at the University of California, Davis, who was also not involved in the new study.

 

By saying our universe was created by a gush of matter from a parent universe, the theory simply shifts the original creation event into an alternate reality.

 

In other words, it doesn't explain how the parent universe came to be or why it has the properties it has—properties our universe presumably inherited.

 

"There're really some pressing problems we're trying to solve, and it's not clear that any of this is offering a way forward with that," he said.

 

Still, Albrecht doesn't find the idea of universe-bridging wormholes any stranger than the idea of black hole singularities, and he cautions against dismissing the new theory just because it sounds a little out there.

 

"Everything people ask in this business is pretty weird," he said. "You can't say the less weird [idea] is going to win, because that's not the way it's been, by any means."

 

http://news.nationalgeographic.com/news/20...link_fb04132010

 

Muito engraçada esta nova teoria.

[Dominator]

li na diagonal...mas por mais bem fundamentado que uma teoria esteja, a verdade é que com novas descobertas tem-se criado mais e mais teorias sobre, por exemplo, os limites do universo, a existencia de multiversos, essas coisas todas.

da bastantes vezes programas sobre isto no Discovery Channel, excelente de se ver.

 

[NIkeL]

Estou a ver um documentário no Odisseia sobre transplantes de cabeça. Vi a história de um transplante de cabeça num macaco e estou simplesmente incrédulo. Não fazia ideia de que já tinha sido feito, com sucesso ainda por cima. O macaco ficou paraplégico, devido à incapacidade de se recuperar a medula, mas basicamente tinham dois macacos, cortaram a cabeça a um e depois meteram a cabeça do segundo no corpo deste. Quando acordou fiquei de boca aberta. Caso se descubra uma forma de recuperar medula, este será um passo incrível no avanço da medicina.

[Black Hawk]

Isso agora deu-me uma dúvida. Nesse caso, a "nova" pessoa é a da cabeça, do corpo ou ambos?

[NIkeL]

A nova pessoa é a da cabeça, obviamente. O que tu és são as tuas memórias e a tua personalidade e isso está no cérebro, o resto é apenas carne e ossos.

[Guest Six Six Six]

A nova pessoa é a da cabeça, obviamente. O que tu és são as tuas memórias e a tua personalidade e isso está no cérebro, o resto é apenas carne e ossos.

há uns tempos (alguns anos, penso) discutia-se se as memórias também não estariam "estacionadas" nos neurónios, isso chegou a ser comprovado?

[Black Hawk]

Então é um transplante de corpo :lol:

 

Que trapalhada, é muito confuso para mim, mexe com valores e conceitos com os quais fui criado.

[Guest Six Six Six]

ainda leva é ao tráfico de cabeças :lol:

[Black Hawk]

Mais de corpo. Até parece que já imagino no futuro um ricaço que quer um corpo musculado a pagar para que roubem o corpo a alguém.

[smashing_pumpkin]

há uns tempos (alguns anos, penso) discutia-se se as memórias também não estariam "estacionadas" nos neurónios, isso chegou a ser comprovado?

 

O processo de aprendizagem/memória já é relativamente conhecido (pelo menos o modo de aquisição). E sim, localiza-se no cérebro.

[Guest Six Six Six]

Mais de corpo. Até parece que já imagino no futuro um ricaço que quer um corpo musculado a pagar para que roubem o corpo a alguém.

Pois, faz mais sentido ser tráfico de corpo de facto. E se isto se confirma, não me admiro nada que esses crimes aconteçam. Está a chegar ao ponto em que a ficção é a realidade.

 

O processo de aprendizagem/memória já é relativamente conhecido (pelo menos o modo de aquisição). E sim, localiza-se no cérebro.

Ah ok nunca tinha percebido bem isso, sou um 0 nas ciências.

[smashing_pumpkin]

Amanhã posso tentar explicar mais ou menos como se processa, só tenho que relembrar umas coisas.

[NIkeL]

A ser possível o transplante de corpo ou como lhe quiserem chamar, haveria tanto mercado negro como há agora para todos os outros órgãos. Sinceramente não sei porque é que tanta gente acha que isto seria moralmente errado, mas não tem qualquer problema como transplantes de qualquer outra parte do corpo. No mesmo documentário, falaram de um homem que tinha ambas as mãos transplantadas e ninguém dizia nada, mas do corpo inteiro, um gajo quase que se sentia ofendido só pelo conceito. Cada vez mais nos centramos no que somos, sendo que o que nos define é o nosso cérebro. Há pessoas que modificam o seu corpo, cirurgias plásticas, tatuagens, piercings, transplantes de partes do corpo ou de órgãos. Porque é que isto é moralmente errado para tanta gente no entanto as coisas que referi são aceites de forma geral pela sociedade? Admito que é algo radical para o que estamos habituados, da mesma forma que muitas das coisas que se fazem agora seriam radicais há 100 anos atrás.

 

Edit

Está a dar novamente o documentário no Odisseia.

[Black Hawk]

É mais por ser uma mudança grande. Eu sou aquilo que sou, as coisas pelo que passei. Por exemplo, olho para a minha mão e relembro-me de uma queda feia que tive de bicicleta quando era puto porque tenho lá a cicatriz. Olho para o meu pé e relembro-me de quando espetei um vidro lá porque lá está a marca. Agora imaginando que troco de corpo, aquilo não sou eu, daria talvez a sensação que estava a usar algo que não me pertence, que não sou eu. Não sei se me faço perceber neste assunto, mas é diferente de trocar de orgãos. É que um orgão é uma pequena parte do corpo, não a sua quase totalidade.

[Lip McBoatface]

A partir do momento em que começarem a matar sem-abrigos ou outras pessoas para fazerem o transplante dele com o velho magnata rico fdmãe sacana e frio.....aí já e imoral :mrgreen:

[NIkeL]

A partir do momento em que começarem a matar sem-abrigos ou outras pessoas para fazerem o transplante dele com o velho magnata rico fdmãe sacana e frio.....aí já e imoral :mrgreen:

Mas isso já fazem agora pelos órgãos, e não é por isso que passa a ser imoral...

[antifa]

Enorme noticia! Cura para ébola testada com sucesso em macacos.

 

Ebola Cured in Monkeys—Hope for Humans?

 

Amitabh Avasthi

for National Geographic News

Published June 9, 2010

 

 

Monkeys infected with the deadly Ebola virus have been treated successfully, possibly bringing humans a step closer to a cure.

 

According to a new study, a team of scientists used special gene-silencing drugs to selectively "knock out" viral proteins in Chinese rhesus macaques infected with a lethal dose of the Zaire Ebola virus. Zaire is the most virulent strain of Ebola—90 percent of infected people die during outbreaks.

 

(Related: "Where Does Ebola Hide Between Epidemics?")

 

Ebola spreads via bodily fluids or tainted needles and razors, and it's highly contagious. Infections in humans and other primates typically cause acute fever and headaches, followed by uncontrollable bleeding from the body's openings. Shock from heavy internal and external bleeding usually proves fatal.

 

Since the virus emerged in central Africa in the late 1970s, people have been searching for ways to prevent or treat Ebola infections. (Take an infectious diseases quiz.)

 

"Ebola is not only of interest because it can cause high mortality, but also because it can be used as a bioterror weapon," said study leader Thomas Geisbert, a virologist at Boston University.

 

"There are a lot of groups working on preventive vaccines, but this is the first time someone has developed a post-exposure treatment."

 

Ebola Virus Blocked From Replicating

 

Geisbert and colleagues used drugs based on synthetic versions of small interfering RNA, or siRNA, a type of molecule in the body that can interfere with the expression of particular genes. (Get a genetics overview.)

 

Since genes are the codes the body uses to make proteins, interfering with specific viral genes should stop production of proteins the Ebola virus needs to survive.

 

"We specifically targeted the L protein, as it kick-starts virus replication," Geisbert said. "If you knock out that protein, you can really inhibit the ability of the virus to replicate."

 

The team also targeted the VP24 and VP35 proteins, which are involved in disabling an infected host's immune response.

 

Seven of the nine monkeys in the study received the same amount of the drug over a six-day period. Three of the seven monkeys got the drug every other day, while four received it daily. One monkey in each group served as a control animal and didn't receive the drug.

 

Analysis of the treated monkeys revealed that, ten days after having been infected with Ebola, the first group of monkeys had very low levels of the virus in their blood. Researchers were unable to detect the virus at all in the group that had received daily doses.

 

"The siRNAs inhibited the replication of the virus and completely protected the monkeys against death from hemorrhagic fever," Geisbert noted. "This has never been done before."

 

(Related: "Ebola Killing Thousands of Gorillas, Study Says.")

 

Ebola Drug Easy to Update

 

Geisbert thinks the real novelty of the study—published May 29 in the journal The Lancet—is that the scientists were able to deliver the drug to infected cells. That can be a challenge, because synthetic siRNA drugs can activate the body's immune system, triggering inflammation.

 

To ferry the drug into cells while preventing unwanted side effects, the researchers packed the drug inside fat molecules.

 

"This capability offers a therapeutic option that has been lacking with certain hemorrhagic fever viruses that have a high level of mortality associated with infections," said Anthony Sanchez, an Ebola researcher at the U.S. Centers for Disease Control and Prevention.

 

Sanchez was part of a team that successfully tested several Ebola vaccines in nonhuman primates and is now trying to adapt the vaccines for use in humans.

 

"The interesting part of the technique is that the [siRNA drug] can be quickly synthesized for a specific strain of Ebola virus," Sanchez added. (Related: "New, Fast-Evolving Rabies Virus Found—And Spreading.")

 

"Thus, if a new strain suddenly appears, whether in Africa or in another region of the world, a therapeutic solution can be quickly generated and deployed for use."

 

Ebola Drug "Long Overdue"

 

Gaya Amarasinghe, a biochemist at Iowa State University, led the team that determined the chemical structure of the VP35 protein, one of the proteins knocked out in the new Ebola study.

 

Amarasinghe called the new work "very exciting," because it's possible the siRNA drug and delivery method could be applied to other filoviruses, the class of viruses—including Ebola—that cause severe hemorrhagic fever.

 

And in a commentary on the study, also published in the Lancet, Heinz Feldmann of the U.S. National Institute of Allergy and Infectious Diseases wrote that the new work is "long overdue and should be considered a milestone in what has been a difficult and frustrating specialty of filovirus research."

 

Study leader Geisbert believes success in curing Ebola in nonhuman primates could translate into a human model for treatment. But the question of human clinical trials for an Ebola drug boils down to funding.

 

"The technology is pretty much ready to go," Geisbert said. But "the small global market for this drug is not much of a financial incentive for drug companies to pursue a vaccine. Investors aren't going to do that—it has to be the government."

 

Amarasinghe agrees, and he also points to the rising cost of doing research with high-priority pathogens. That's because, inflation aside, researchers need highly secure—and thus expensive—biocontainment facilities to study these deadly diseases.

 

"Under the FDA's 'animal rule,' potential drugs that perform well in animal-efficacy studies can be substituted for human clinical trials, as long as appropriate human safety studies have been conducted," he explained.

 

"Ebola can qualify under that rule, and if promising candidates [for drugs] are identified, at the very least, mechanisms are in place to move them forward into the product-development phase."

 

The new Ebola drug study included scientific collaboration with Tekmira Pharmaceuticals and the United States Army Medical Research Institute of Infectious Diseases.

 

http://news.nationalgeographic.com/news/2010/06/100609-science-health-ebola-virus-cure-vaccine-monkeys/?source=link_fb06092010b

[Lip McBoatface]

Excelente se se vier a concretizar.

[Ghelthon]

Não conhecia a doença, tive de pesquisar na Wikipedia, e pareceu-me bem chata. Ainda bem que se encontrou essa possível cura.

[Jone Sampaoli]

é provavelmente a par do HIV/SIDA a doença mais mortal no planeta se for apanhada. É uma excelente notícia.

[antifa]

Não se espalha tão facilmente como a Sida e por isso não é tão perigoso, mas em termos de mortalidade é bem pior.