Re: Our universe is so rad!
Mon May 20, 2013 5:09 am
Probably the same amount that have always flown by, but we're just able to detect them better with modern technology.
Re: Our universe is so rad!
Mon May 20, 2013 5:17 am
dimejinky99 wrote:We've had a really large amount of 'fly bys' by extinction level asteroids the last few years. More than I remember being mentioned before. I wonder if the one with our name on it is on its way?
It's only a matter of galactic time before it arrives. How much will that be in human years though?
The chances of us being hit by an "extinction level asteroid" grows slimmer with each year. I believe “planetary defense” is now NASA's No. 1 goal. With tracking technologies, we would know several months (if not years) in advance of any serious threat and be able to act against it.
Re: Our universe is so rad!
Mon May 20, 2013 5:23 am
Really?Didn't know that. Thanks. So we're back to us being our own biggest threat against our survival. That I can live with. Sure we all grew up with that 
Re: Our universe is so rad!
Mon May 20, 2013 5:48 am
dimejinky99 wrote:Really?Didn't know that. Thanks. So we're back to us being our own biggest threat against our survival. That I can live with. Sure we all grew up with that
Oh don't worry, there are signs that Yellowstone will have a "super-eruption" in the next 200 years or so. And about a month ago they discovered that the magma chamber under it is much larger than they thought. You still have plenty to worry about.
Re: Our universe is so rad!
Tue May 28, 2013 1:09 am
400-year-old frozen moss brought back to life in scientist’s lab
BY SHEILA PRATT
EDMONTON JOURNAL
EDMONTON - In Arctic summers, Catherine La Farge camps out at the toe of the Teardrop glacier on Ellesmere Island in Canada’s North.
The University of Alberta biologist has watched the ice retreat, up to four metres a year now, giving her an unprecedented view of what was entombed under the ice for 400 years — old rocks, mud, and her specialty, ancient moss.
One day, walking along the edge of the ice, La Farge noticed some of the moss had a greenish tinge. That gave her a hunch — could there be life in that old moss after all?
In an amazing experiment, La Farge found the frozen moss was able to revive itself though it had been buried since the Little Ice Age (1550-1850). Her study, published this week in the Proceedings of the National Academy of Science, is shaking up some basic assumptions about land plants.
In the past, when scientists occasionally came across plant material previously frozen under an Arctic glacier, they assumed the plant material was dead. Discoloured and lifeless, it certainly looked like it was.
In 2009, La Farge brought samples back to the lab. On closer examination, she noticed a tiny green stem. There were two possible explanations.
“Either it kept its colour under the glacier or it grew after the moss emerged 400 years later.”
There was only one way to find out.
La Farge ground up the old plant material, put it in petri dishes full of potting soil and set it in the grow chamber next to her office. Then she and graduate student Krista Williams and master’s student David Wilkie watched for signs of life.
It didn’t take long. In about four to six weeks, tiny green filaments or strands called protonema began to grow.
Months later, a dish was almost full of green moss from cells frozen for 400 years. Of 24 samples potted, seven produced new growth.
“It was just incredible,” said La Farge, whose work has given scientists another window into the basic life systems of plants.
“Now we have Little Ice Age moss material that produced juvenile plants.”
In glaciers, there are all kinds of fungi and bacteria, but no one has ever considered that land plants could survive being entombed underneath, she said.
“Now we have to think there may be populations of land plants that survived that freezing. It makes you wonder what’s under the big ice caps in the Arctic and Antarctic and alpine glaciers.
“And we have a 400-year-old lineage of genetic material,” she added.
Mosses are especially hardy and ancient — 400 million years old, she said. Mosses played a key role in moving life from water to land in evolution. They evolved from green algae and paved the way for other land plants.
Unlike most other plants, mosses reproduce by cloning their cells so “all you need is even one cell to survive.”
Also, moss cells are very powerful — totipotent is the scientific term — because they can reprogram themselves to start growth all over again.
La Farge’s work shows that ability to regenerate — the totipotency of a cell — doesn’t diminish with age, at least not over 400 frozen years.
“If we could find some moss that went back 1,000 years or 5,000 years we may find some material that could be revived. But it all depends on the specific way the material is buried and the conditions” — cold and dry is best.
A group of researchers in Germany is already using bryophyte cells — basically moss stem cells — in medical research. La Farge’s work shows the resilience of the cells which could be a factor in their use.
There might be uses. Before sending colonies of humans to Mars, it might be worth seeing how well moss survives the cold dry climate, she said.
La Forge’s discovery shakes up a few assumptions of glacial science, a major one being that as glaciers carved their way forward they crushed everything beneath them. The landscape from retreating ice can no longer be considered barren of land plants ready to grow again. Mosses could be a key agent for regenerating the land.
There’s one other significant aspect to this discovery. While biological diversity is shrinking in the world, the frozen world under glaciers could provide an “unrecognized genetic reservoir.”
These are reservoirs that could be tapped in the future,” La Farge said.
“We really have not examined all the biological systems that exist in the world; we don’t know it all.
“We need curiosity-driven research to make these discoveries.”
La Farge’s co-authors on the study include Williams, Wilkie and Arctic researcher John England, also at the University of Alberta.
http://www.edmontonjournal.com/technolo ... story.html
BY SHEILA PRATT
EDMONTON JOURNAL
EDMONTON - In Arctic summers, Catherine La Farge camps out at the toe of the Teardrop glacier on Ellesmere Island in Canada’s North.
The University of Alberta biologist has watched the ice retreat, up to four metres a year now, giving her an unprecedented view of what was entombed under the ice for 400 years — old rocks, mud, and her specialty, ancient moss.
One day, walking along the edge of the ice, La Farge noticed some of the moss had a greenish tinge. That gave her a hunch — could there be life in that old moss after all?
In an amazing experiment, La Farge found the frozen moss was able to revive itself though it had been buried since the Little Ice Age (1550-1850). Her study, published this week in the Proceedings of the National Academy of Science, is shaking up some basic assumptions about land plants.
In the past, when scientists occasionally came across plant material previously frozen under an Arctic glacier, they assumed the plant material was dead. Discoloured and lifeless, it certainly looked like it was.
In 2009, La Farge brought samples back to the lab. On closer examination, she noticed a tiny green stem. There were two possible explanations.
“Either it kept its colour under the glacier or it grew after the moss emerged 400 years later.”
There was only one way to find out.
La Farge ground up the old plant material, put it in petri dishes full of potting soil and set it in the grow chamber next to her office. Then she and graduate student Krista Williams and master’s student David Wilkie watched for signs of life.
It didn’t take long. In about four to six weeks, tiny green filaments or strands called protonema began to grow.
Months later, a dish was almost full of green moss from cells frozen for 400 years. Of 24 samples potted, seven produced new growth.
“It was just incredible,” said La Farge, whose work has given scientists another window into the basic life systems of plants.
“Now we have Little Ice Age moss material that produced juvenile plants.”
In glaciers, there are all kinds of fungi and bacteria, but no one has ever considered that land plants could survive being entombed underneath, she said.
“Now we have to think there may be populations of land plants that survived that freezing. It makes you wonder what’s under the big ice caps in the Arctic and Antarctic and alpine glaciers.
“And we have a 400-year-old lineage of genetic material,” she added.
Mosses are especially hardy and ancient — 400 million years old, she said. Mosses played a key role in moving life from water to land in evolution. They evolved from green algae and paved the way for other land plants.
Unlike most other plants, mosses reproduce by cloning their cells so “all you need is even one cell to survive.”
Also, moss cells are very powerful — totipotent is the scientific term — because they can reprogram themselves to start growth all over again.
La Farge’s work shows that ability to regenerate — the totipotency of a cell — doesn’t diminish with age, at least not over 400 frozen years.
“If we could find some moss that went back 1,000 years or 5,000 years we may find some material that could be revived. But it all depends on the specific way the material is buried and the conditions” — cold and dry is best.
A group of researchers in Germany is already using bryophyte cells — basically moss stem cells — in medical research. La Farge’s work shows the resilience of the cells which could be a factor in their use.
There might be uses. Before sending colonies of humans to Mars, it might be worth seeing how well moss survives the cold dry climate, she said.
La Forge’s discovery shakes up a few assumptions of glacial science, a major one being that as glaciers carved their way forward they crushed everything beneath them. The landscape from retreating ice can no longer be considered barren of land plants ready to grow again. Mosses could be a key agent for regenerating the land.
There’s one other significant aspect to this discovery. While biological diversity is shrinking in the world, the frozen world under glaciers could provide an “unrecognized genetic reservoir.”
These are reservoirs that could be tapped in the future,” La Farge said.
“We really have not examined all the biological systems that exist in the world; we don’t know it all.
“We need curiosity-driven research to make these discoveries.”
La Farge’s co-authors on the study include Williams, Wilkie and Arctic researcher John England, also at the University of Alberta.
http://www.edmontonjournal.com/technolo ... story.html
Re: Our universe is so rad!
Wed June 05, 2013 3:31 am
Life may have been boosted by asteroid impacts
By Staff
The Space Reporter
It seems life may have received a boost from asteroids smashing into the surface of Earth early in its life.
According to a newly published report produced by researchers at the University of South Florida (USF) and the University of Washington, life-producing phosphorus may have landed on Earth 3.5 billion years ago, providing a boost to early life forms.
USF professor Matthew Pasek, who led the study, says the phosphorus, when released in water, may have over time incorporated themselves into prebiotic molecules. The phosphorus, which has been found in asteroids, was likely carried to Earth via comets and meteorites, which released the element when impacted Earth.
By focusing on the Hadean and Archean eons of early Earth, the scientists were able to discern that meteorites delivered phosphorus in minerals currently not seen on the surface of Earth. By examining Earth core samples from Zimbabwe, Australia, Wyoming, West Virginia, Florida the team was able to determine the origin of the minerals. According to researchers, the minerals likely corroded in water, releasing large amounts of phosphorus in a form only found during Earth’s early formation. The phosphite would have likely resulted in an adjusting of the chemistry of Earth’s early oceans, with its chemical signature later becoming trapped in marine carbonate where it was preserved.
“The importance of this finding is that it provides the missing ingredient in the origin-of-life recipe: a form of phosphorus that can be readily incorporated into essential biological molecules,” said Roger Buick, a co-author of the study.
There are few natural sources of phosphite that are Earth-based. Some of the examples include lightning strikes, geothermal fluids and possibly microbial activity under extremely anaerobic condition. However, none of the Earth-based forms could have produced the quantities of phosphite needed to be dissolved in early Earth oceans that gave rise to life, according to researchers.
According to the report, the conditions that led to a boom of life on Earth no longer exist and the elements delivered by asteroids are few and far between. Previous research has already confirmed that before the emergence of DNA-RNA-protein life , the earliest forms of life on Earth evolved by relying on RNA alone. While the evolution of early life is fairly well understood, it remained unclear how early RNA–based life forms synthesized environmental phosphorus, which in its current form is relatively insoluble and unreactive.
This is not the first study to propose how life may have evolve from elements delivered to Earth via asteroids and comets. A number of scientists have examined and noted the abundance of reactive phosphorus in the form of the mineral schreibersite, a iron–nickel phosphide.
The report is published in the latest edition of the Proceedings of the National Academy of Sciences.
http://thespacereporter.com/2013/06/sci ... eteorites/
By Staff
The Space Reporter
It seems life may have received a boost from asteroids smashing into the surface of Earth early in its life.
According to a newly published report produced by researchers at the University of South Florida (USF) and the University of Washington, life-producing phosphorus may have landed on Earth 3.5 billion years ago, providing a boost to early life forms.
USF professor Matthew Pasek, who led the study, says the phosphorus, when released in water, may have over time incorporated themselves into prebiotic molecules. The phosphorus, which has been found in asteroids, was likely carried to Earth via comets and meteorites, which released the element when impacted Earth.
By focusing on the Hadean and Archean eons of early Earth, the scientists were able to discern that meteorites delivered phosphorus in minerals currently not seen on the surface of Earth. By examining Earth core samples from Zimbabwe, Australia, Wyoming, West Virginia, Florida the team was able to determine the origin of the minerals. According to researchers, the minerals likely corroded in water, releasing large amounts of phosphorus in a form only found during Earth’s early formation. The phosphite would have likely resulted in an adjusting of the chemistry of Earth’s early oceans, with its chemical signature later becoming trapped in marine carbonate where it was preserved.
“The importance of this finding is that it provides the missing ingredient in the origin-of-life recipe: a form of phosphorus that can be readily incorporated into essential biological molecules,” said Roger Buick, a co-author of the study.
There are few natural sources of phosphite that are Earth-based. Some of the examples include lightning strikes, geothermal fluids and possibly microbial activity under extremely anaerobic condition. However, none of the Earth-based forms could have produced the quantities of phosphite needed to be dissolved in early Earth oceans that gave rise to life, according to researchers.
According to the report, the conditions that led to a boom of life on Earth no longer exist and the elements delivered by asteroids are few and far between. Previous research has already confirmed that before the emergence of DNA-RNA-protein life , the earliest forms of life on Earth evolved by relying on RNA alone. While the evolution of early life is fairly well understood, it remained unclear how early RNA–based life forms synthesized environmental phosphorus, which in its current form is relatively insoluble and unreactive.
This is not the first study to propose how life may have evolve from elements delivered to Earth via asteroids and comets. A number of scientists have examined and noted the abundance of reactive phosphorus in the form of the mineral schreibersite, a iron–nickel phosphide.
The report is published in the latest edition of the Proceedings of the National Academy of Sciences.
http://thespacereporter.com/2013/06/sci ... eteorites/
Re: Our universe is so rad!
Sat June 22, 2013 10:32 pm
space penguin?!
Re: Our universe is so rad!
Sun June 23, 2013 10:08 pm
Whatever it is, its pretty cool looking
Re: Our universe is so rad!
Wed September 04, 2013 4:01 am
Poop shield could protect astronauts during trip to Mars
Video: http://news.discovery.com/videos/poop-s ... onauts.htm
Video: http://news.discovery.com/videos/poop-s ... onauts.htm
Re: Our universe is so rad!
Wed September 04, 2013 1:19 pm
God is great.
thank you for this food.
elliseamos wrote:god is good.
thank you for this food.
Re: Our universe is so rad!
Wed September 04, 2013 8:41 pm
knee tunes wrote:God is great.elliseamos wrote:god is good.
thank you for this food.
you're welcome.
Re: Our universe is so rad!
Fri September 13, 2013 12:57 am
I'm so into everything Voyager it's sickening.
Re: Our universe is so rad!
Fri September 13, 2013 12:01 pm
Re: Our universe is so rad!
Wed September 18, 2013 11:16 pm
Did a hyper-black hole spawn the Universe?
Big Bang was mirage from collapsing higher-dimensional star, theorists propose.
By Zeeya Merali
It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole — a scenario that would help to explain why the cosmos seems to be so uniform in all directions.
The standard Big Bang model tells us that the Universe exploded out of an infinitely dense point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment.
“For all physicists know, dragons could have come flying out of the singularity,” says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.
It is also difficult to explain how a violent Big Bang would have left behind a Universe that has an almost completely uniform temperature, because there does not seem to have been enough time since the birth of the cosmos for it to have reached temperature equilibrium.
To most cosmologists, the most plausible explanation for that uniformity is that, soon after the beginning of time, some unknown form of energy made the young Universe inflate at a rate that was faster than the speed of light. That way, a small patch with roughly uniform temperature would have stretched into the vast cosmos we see today. But Afshordi notes that “the Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on”.
On the brane
In a paper posted last week on the arXiv preprint server1, Afshordi and his colleagues turn their attention to a proposal2 made in 2000 by a team including Gia Dvali, a physicist now at the Ludwig Maximilians University in Munich, Germany. In that model, our three-dimensional (3D) Universe is a membrane, or brane, that floats through a ‘bulk universe’ that has four spatial dimensions.
Ashfordi's team realized that if the bulk universe contained its own four-dimensional (4D) stars, some of them could collapse, forming 4D black holes in the same way that massive stars in our Universe do: they explode as supernovae, violently ejecting their outer layers, while their inner layers collapse into a black hole.
In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object — a shape called a hypersphere. When Afshordi’s team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand.
The authors postulate that the 3D Universe we live in might be just such a brane — and that we detect the brane’s growth as cosmic expansion. “Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang — but that is just a mirage,” says Afshordi.
Model discrepancy
The model also naturally explains our Universe’s uniformity. Because the 4D bulk universe could have existed for an infinitely long time in the past, there would have been ample opportunity for different parts of the 4D bulk to reach an equilibrium, which our 3D Universe would have inherited.
The picture has some problems, however. Earlier this year, the European Space Agency's Planck space observatory released data that mapped the slight temperature fluctuations in the cosmic microwave background — the relic radiation that carries imprints of the Universe’s early moments. The observed patterns matched predictions made by the standard Big Bang model and inflation, but the black-hole model deviates from Planck's observations by about 4%. Hoping to resolve the discrepancy, Afshordi says that his is now refining its model.
Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model. “The singularity is the most fundamental problem in cosmology and they have rewritten history so that we never encountered it,” he says. Whereas the Planck results “prove that inflation is correct”, they leave open the question of how inflation happened, Dvali adds. The study could help to show how inflation is triggered by the motion of the Universe through a higher-dimensional reality, he says.
http://www.nature.com/news/did-a-hyper- ... se-1.13743
Big Bang was mirage from collapsing higher-dimensional star, theorists propose.
By Zeeya Merali
It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole — a scenario that would help to explain why the cosmos seems to be so uniform in all directions.
The standard Big Bang model tells us that the Universe exploded out of an infinitely dense point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment.
“For all physicists know, dragons could have come flying out of the singularity,” says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.
It is also difficult to explain how a violent Big Bang would have left behind a Universe that has an almost completely uniform temperature, because there does not seem to have been enough time since the birth of the cosmos for it to have reached temperature equilibrium.
To most cosmologists, the most plausible explanation for that uniformity is that, soon after the beginning of time, some unknown form of energy made the young Universe inflate at a rate that was faster than the speed of light. That way, a small patch with roughly uniform temperature would have stretched into the vast cosmos we see today. But Afshordi notes that “the Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on”.
On the brane
In a paper posted last week on the arXiv preprint server1, Afshordi and his colleagues turn their attention to a proposal2 made in 2000 by a team including Gia Dvali, a physicist now at the Ludwig Maximilians University in Munich, Germany. In that model, our three-dimensional (3D) Universe is a membrane, or brane, that floats through a ‘bulk universe’ that has four spatial dimensions.
Ashfordi's team realized that if the bulk universe contained its own four-dimensional (4D) stars, some of them could collapse, forming 4D black holes in the same way that massive stars in our Universe do: they explode as supernovae, violently ejecting their outer layers, while their inner layers collapse into a black hole.
In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object — a shape called a hypersphere. When Afshordi’s team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand.
The authors postulate that the 3D Universe we live in might be just such a brane — and that we detect the brane’s growth as cosmic expansion. “Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang — but that is just a mirage,” says Afshordi.
Model discrepancy
The model also naturally explains our Universe’s uniformity. Because the 4D bulk universe could have existed for an infinitely long time in the past, there would have been ample opportunity for different parts of the 4D bulk to reach an equilibrium, which our 3D Universe would have inherited.
The picture has some problems, however. Earlier this year, the European Space Agency's Planck space observatory released data that mapped the slight temperature fluctuations in the cosmic microwave background — the relic radiation that carries imprints of the Universe’s early moments. The observed patterns matched predictions made by the standard Big Bang model and inflation, but the black-hole model deviates from Planck's observations by about 4%. Hoping to resolve the discrepancy, Afshordi says that his is now refining its model.
Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model. “The singularity is the most fundamental problem in cosmology and they have rewritten history so that we never encountered it,” he says. Whereas the Planck results “prove that inflation is correct”, they leave open the question of how inflation happened, Dvali adds. The study could help to show how inflation is triggered by the motion of the Universe through a higher-dimensional reality, he says.
http://www.nature.com/news/did-a-hyper- ... se-1.13743
Re: Our universe is so rad!
Thu September 19, 2013 3:01 am
woah
Re: Our universe is so rad!
Thu October 24, 2013 8:43 pm
Space travel: U.S. company to offer 30 km-high balloon flights
(CNN) -- Want space travel but don't have pockets deep enough for Richard Branson's Virgin Galactic or the courage levels to match Felix Baumgartner, the daredevil space-jumper? A balloon trip to (almost) space and back might just be the answer.
Arizona-based space travel company World View Enterprises says it plans to offer a trip to the edge of space in a luxurious eight-seat capsule for $75,000 per ticket.
It's somewhat more affordable considering Virgin Galactic charges $250,000, which also includes three days of training and two and a half hours in space.
The capsule will be lifted by a high altitude balloon that will rise up to about 30 kilometers (98,425 feet or almost 20 miles) and stay aloft for two hours before returning back to Earth, according to a company press statement.
Quiz: Do you have the smarts to be a space tourist?
That is not as high as Baumgartner's jumping point (128,100 feet or around 39 kilometers) last year but much higher than one can usually reach -- the average altitude for commercial flights is about nine or ten kilometers above ground, or 30,000 to 40,000 feet.
"Passengers will be among the few to have seen the curvature of the Earth with their own eyes," the statement touted.
"They will be able to gaze at the astounding views, the blackness of space, the brilliance of stars and the thin veil of atmosphere enveloping our planet."
The first flight is planned for 2016.
Component testing has already begun and sub-scale testing will soon be carried out as well, the company says.
The space capsule will be developed by Paragon Space Development Corporation, which is developing technology for Inspiration Mars, a 501-day mission around Mars.
http://www.cnn.com/2013/10/24/travel/sp ... loon-30km/
Re: Our universe is so rad!
Thu October 24, 2013 8:49 pm
turned2black wrote:Did a hyper-black hole spawn the Universe?
Big Bang was mirage from collapsing higher-dimensional star, theorists propose.
By Zeeya Merali
It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole — a scenario that would help to explain why the cosmos seems to be so uniform in all directions.
The standard Big Bang model tells us that the Universe exploded out of an infinitely dense point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment.
“For all physicists know, dragons could have come flying out of the singularity,” says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.
It is also difficult to explain how a violent Big Bang would have left behind a Universe that has an almost completely uniform temperature, because there does not seem to have been enough time since the birth of the cosmos for it to have reached temperature equilibrium.
To most cosmologists, the most plausible explanation for that uniformity is that, soon after the beginning of time, some unknown form of energy made the young Universe inflate at a rate that was faster than the speed of light. That way, a small patch with roughly uniform temperature would have stretched into the vast cosmos we see today. But Afshordi notes that “the Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on”.
On the brane
In a paper posted last week on the arXiv preprint server1, Afshordi and his colleagues turn their attention to a proposal2 made in 2000 by a team including Gia Dvali, a physicist now at the Ludwig Maximilians University in Munich, Germany. In that model, our three-dimensional (3D) Universe is a membrane, or brane, that floats through a ‘bulk universe’ that has four spatial dimensions.
Ashfordi's team realized that if the bulk universe contained its own four-dimensional (4D) stars, some of them could collapse, forming 4D black holes in the same way that massive stars in our Universe do: they explode as supernovae, violently ejecting their outer layers, while their inner layers collapse into a black hole.
In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object — a shape called a hypersphere. When Afshordi’s team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand.
The authors postulate that the 3D Universe we live in might be just such a brane — and that we detect the brane’s growth as cosmic expansion. “Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang — but that is just a mirage,” says Afshordi.
Model discrepancy
The model also naturally explains our Universe’s uniformity. Because the 4D bulk universe could have existed for an infinitely long time in the past, there would have been ample opportunity for different parts of the 4D bulk to reach an equilibrium, which our 3D Universe would have inherited.
The picture has some problems, however. Earlier this year, the European Space Agency's Planck space observatory released data that mapped the slight temperature fluctuations in the cosmic microwave background — the relic radiation that carries imprints of the Universe’s early moments. The observed patterns matched predictions made by the standard Big Bang model and inflation, but the black-hole model deviates from Planck's observations by about 4%. Hoping to resolve the discrepancy, Afshordi says that his is now refining its model.
Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model. “The singularity is the most fundamental problem in cosmology and they have rewritten history so that we never encountered it,” he says. Whereas the Planck results “prove that inflation is correct”, they leave open the question of how inflation happened, Dvali adds. The study could help to show how inflation is triggered by the motion of the Universe through a higher-dimensional reality, he says.
http://www.nature.com/news/did-a-hyper- ... se-1.13743
where did the 4 dimensional star that caused the black hole come from? I'm not sure the inability to explain the singularity is a problem with that theory. If this explains other elements of our universe than great.
Re: Our universe is so rad!
Thu October 24, 2013 9:47 pm
stip wrote:where did the 4 dimensional star that caused the black hole come from? I'm not sure the inability to explain the singularity is a problem with that theory. If this explains other elements of our universe than great.
Why did it need to come from anywhere? Why can't the universe have always existed? Singularity and first cause are really just religious dogma at this point. If someone thinks a creator made the universe, then who created the creator? If the answer is the creator has always existed, then why the hell can't the universe have always existed? It's an endless cycle.
Last edited by nyquillyn on Thu October 24, 2013 11:13 pm, edited 1 time in total.
Re: Our universe is so rad!
Thu October 24, 2013 9:59 pm
That's hurting my head to try and understand.
hyper black hole from a 4 dimensional sun. So there was something before this. And it was bigger and had more dimensions.
So everything is getting smaller after all.
Ever diminishing circles I guess.
Ouch
hyper black hole from a 4 dimensional sun. So there was something before this. And it was bigger and had more dimensions.
So everything is getting smaller after all.
Ever diminishing circles I guess.
Ouch
Re: Our universe is so rad!
Thu October 24, 2013 11:59 pm
turned2black wrote:stip wrote:where did the 4 dimensional star that caused the black hole come from? I'm not sure the inability to explain the singularity is a problem with that theory. If this explains other elements of our universe than great.
Why did it need to come from anywhere? Why can't the universe have always existed? Singularity and first cause are really just religious dogma at this point. If someone thinks a creator made the universe, then who created the creator? If the answer is the creator has always existed, then why the hell can't the universe have always existed? It's an endless cycle.
Totally agree. That was kind of my point