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Post by gus on Apr 19, 2021 23:51:56 GMT
WOW just in! I suspect massive space craft next to the moon seen in Australia and America at the same time. The size of it must be massive....my mind is blown!
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Post by swamprat on Apr 24, 2021 2:41:37 GMT
Warp drives: Physicists give chances of faster–than–light space travel a boost
Mario Borunda, Associate Professor of Physics, Oklahoma State University 8 hrs ago
The closest star to Earth is Proxima Centauri. It is about 4.25 light-years away, or about 25 trillion miles (40 trillion km). The fastest ever spacecraft, the now- in-space Parker Solar Probe will reach a top speed of 450,000 mph. It would take just 20 seconds to go from Los Angeles to New York City at that speed, but it would take the solar probe about 6,633 years to reach Earth’s nearest neighboring solar system.
If humanity ever wants to travel easily between stars, people will need to go faster than light. But so far, faster-than-light travel is possible only in science fiction.
In Issac Asimov’s Foundation series, humanity can travel from planet to planet, star to star or across the universe using jump drives. As a kid, I read as many of those stories as I could get my hands on. I am now a theoretical physicist and study nanotechnology, but I am still fascinated by the ways humanity could one day travel in space.
Some characters – like the astronauts in the movies “Interstellar” and “Thor” – use wormholes to travel between solar systems in seconds. Another approach – familiar to “Star Trek” fans – is warp drive technology. Warp drives are theoretically possible if still far-fetched technology. Two recent papers made headlines in March when researchers claimed to have overcome one of the many challenges that stand between the theory of warp drives and reality.
But how do these theoretical warp drives really work? And will humans be making the jump to warp speed anytime soon?
Compression and expansion
Physicists’ current understanding of spacetime comes from Albert Einstein’s theory of General Relativity. General Relativity states that space and time are fused and that nothing can travel faster than the speed of light. General relativity also describes how mass and energy warp spacetime – hefty objects like stars and black holes curve spacetime around them. This curvature is what you feel as gravity and why many spacefaring heroes worry about “getting stuck in” or “falling into” a gravity well. Early science fiction writers John Campbell and Asimov saw this warping as a way to skirt the speed limit.
What if a starship could compress space in front of it while expanding spacetime behind it? “Star Trek” took this idea and named it the warp drive.
In 1994, Miguel Alcubierre, a Mexican theoretical physicist, showed that compressing spacetime in front of the spaceship while expanding it behind was mathematically possible within the laws of General Relativity. So, what does that mean? Imagine the distance between two points is 10 meters (33 feet). If you are standing at point A and can travel one meter per second, it would take 10 seconds to get to point B. However, let’s say you could somehow compress the space between you and point B so that the interval is now just one meter. Then, moving through spacetime at your maximum speed of one meter per second, you would be able to reach point B in about one second. In theory, this approach does not contradict the laws of relativity since you are not moving faster than light in the space around you. Alcubierre showed that the warp drive from “Star Trek” was in fact theoretically possible.
Proxima Centauri here we come, right? Unfortunately, Alcubierre’s method of compressing spacetime had one problem: it requires negative energy or negative mass.
A negative energy problem
Alcubierre’s warp drive would work by creating a bubble of flat spacetime around the spaceship and curving spacetime around that bubble to reduce distances. The warp drive would require either negative mass – a theorized type of matter – or a ring of negative energy density to work. Physicists have never observed negative mass, so that leaves negative energy as the only option.
To create negative energy, a warp drive would use a huge amount of mass to create an imbalance between particles and antiparticles. For example, if an electron and an antielectron appear near the warp drive, one of the particles would get trapped by the mass and this results in an imbalance. This imbalance results in negative energy density. Alcubierre’s warp drive would use this negative energy to create the spacetime bubble.
But for a warp drive to generate enough negative energy, you would need a lot of matter. Alcubierre estimated that a warp drive with a 100-meter bubble would require the mass of the entire visible universe.
In 1999, physicist Chris Van Den Broeck showed that expanding the volume inside the bubble but keeping the surface area constant would reduce the energy requirements significantly, to just about the mass of the sun. A significant improvement, but still far beyond all practical possibilities.
A sci-fi future?
Two recent papers – one by Alexey Bobrick and Gianni Martire and another by Erik Lentz – provide solutions that seem to bring warp drives closer to reality.
Bobrick and Martire realized that by modifying spacetime within the bubble in a certain way, they could remove the need to use negative energy. This solution, though, does not produce a warp drive that can go faster than light.
Independently, Lentz also proposed a solution that does not require negative energy. He used a different geometric approach to solve the equations of General Relativity, and by doing so, he found that a warp drive wouldn’t need to use negative energy. Lentz’s solution would allow the bubble to travel faster than the speed of light.
It is essential to point out that these exciting developments are mathematical models. As a physicist, I won’t fully trust models until we have experimental proof. Yet, the science of warp drives is coming into view. As a science fiction fan, I welcome all this innovative thinking. In the words of Captain Picard, things are only impossible until they are not.
This article is republished from The Conversation under a Creative Commons license. Mario Borunda does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
Warp drives: Physicists give chances of faster–than–light space travel a boost (msn.com)
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Post by gus on May 5, 2021 8:11:16 GMT
Had a dream about this about 15 years ago and now here we are! Thousands of UFOs!
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Post by gus on May 6, 2021 22:11:46 GMT
Bit of a stretch.
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Post by gus on May 8, 2021 1:00:06 GMT
So do we have a fleet of UFOs constantly patrolling the Earth?
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Post by swamprat on May 11, 2021 14:15:56 GMT
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Post by gus on May 12, 2021 23:24:43 GMT
Scratching my head on this one. Seen a few of these now. Earth sized UFOs or cold spots off the sun? Either way the size is mind boggling. See at 5:22
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Post by gus on May 14, 2021 0:45:21 GMT
Yes a fleet regularly fly around Earth!
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Post by swamprat on May 28, 2021 13:50:28 GMT
Mysterious radio burst from space is unusually close—and especially baffling
Nadia Drake - May 27, 2021
Bright, fleeting blasts of radio waves coming from the vicinity of a nearby galaxy are deepening one of astronomy’s biggest mysteries. The repeating bursts of energy seem to be coming from an ancient group of stars called a globular cluster, which is among the last places astronomers expected to find them.
Often originating billions of light-years away, the extremely bright, extremely brief bursts of radio waves known as fast radio bursts, or FRBs, have defied explanation since they were first spotted in 2007. Based on observations to date, scientists surmised that the bursts are powered by young, short-lived cosmic objects called magnetars.
But a fast radio burst discovered last year has now been traced to a globular cluster about 11.7 million light-years away, near the neighboring spiral galaxy M81, according to a paper describing the discovery posted on the scientific preprint server arXiv. Finding this burst among a cluster of aging stars is kind of like finding a smartphone embedded in Stonehenge—the observation doesn’t make sense.
“This is definitely not a place fast radio bursts are expected to live,” Bryan Gaensler, an astronomer at the University of Toronto and a co-author of the new paper, posted on Twitter. “Just what is going on?” Scientists are struggling to explain the cosmic anachronism. They’re also moving toward the conclusion that maybe, as with many other celestial phenomena, there are multiple ways to cook up a fast radio burst. “FRBs might be—might be—just this generic phenomenon associated with a whole range of possible sources,” says Cornell University astronomer Shami Chatterjee, who studies the bursts but is not part of the discovery team.
“What is happening here?” Scientists first spotted the burst, dubbed FRB 20200120E, in January 2020 using the Canada Hydrogen Intensity Mapping Experiment (CHIME) telescope, which has proven to be a relentless FRB-finding machine. When CHIME came online in 2017, scientists knew of fewer than 30 fast radio bursts; now the telescope has boosted that total to well over a thousand. Like at least two dozen known bursts, FRB 20200120E is a repeater—a space engine that produces multiple detectable blasts of radio waves, rather than exploding once and vanishing. Its bursts are not as bright as those coming from billions of light-years away, in the distant cosmos, but over the last year, they’ve allowed scientists to identify the FRB’s location in the sky.
From there, the team could attempt to identify a source. Measurements of the bursts suggested that FRB 20200120E was quite nearby, so astronomers knew they were hunting for something local, perhaps even within the Milky Way’s gassy, sparsely populated halo. Scientists then used a network of radio telescopes known as the European Very Long Baseline Interferometry Network to pinpoint the burst’s precise location.
“We conclusively prove that FRB 20200120E is associated with a globular cluster in the M81 galactic system, thereby confirming that it is 40 times closer than any other known extragalactic FRB,” the authors write in the new paper.
“The interpretation of that is where things get very, very interesting,” Chatterjee says. “It is very hard to fit into existing models.”
Globular clusters are some of the most ancient objects in the observable universe. They’re billions of years old, at least as old as the galaxies they orbit, and perhaps much older. Until now, scientists strongly suspected that fast radio bursts were produced by some of the youngest compact objects yet observed—magnetars, or extremely magnetic, flaring stellar corpses produced when young, massive stars explode and die. Once formed, the ultramagnetic stellar corpse lingers for tens of thousands of years before its magnetic field decays, leaving a more ordinary neutron star.
But as far as astronomers know, these sparkling, densely packed globular clusters don’t contain the kinds of tempestuous stars that collapse into magnetars.
“This type of star formation is happening all around the universe, even in our own galaxy in many places, but not in globular clusters,” says Northwestern University’s Claire Ye, who studies globular clusters. ”It’s like, wow, what is happening here?”
Extremely magnetic, ultra-dense stars It’s taken nearly 15 years to begin untangling the mystery of fast radio bursts. Initial hypotheses included evaporating black holes, flaring dead stars, colliding dense objects, and yes, even alien technologies (spoiler: it’s not aliens). Further clues, from nano-scale structures within the radio bursts to their millisecond duration and intensity, suggested they must be produced by extremely dense, compact objects.
So, scientists turned to objects such as black holes and neutron stars, which are left over when massive stars blow themselves to bits in supernovae. Later, observations suggested that some bursts are born in regions with extreme magnetic fields, further suggesting these mysterious signals could come from magnetars.
Then, last year, a magnetar within the Milky Way produced a radio burst resembling an FRB. The blast was a bit wimpier than the extremely powerful bursts coming from a half a universe away, but scientists were convinced they were on the right track. “The paradigm that FRBs come from magnetars has taken on quite a life since we saw the FRB-like burst from the galactic magnetar,” says Brian Metzger of Columbia University and the Flatiron Institute. “You had a situation where both the theorists and the observers were pretty happy with magnetars.”
But that didn’t last long. With the discovery of FRB 20200120E, astronomers now need to figure out how magnetars might arise and survive in globular clusters, or they need to figure out how a population of extremely old, quiet stars can generate such powerful blasts. Neither is an easy problem to solve.
Plausible explanations While astronomers don’t think globular clusters contain magnetars, other types of stellar corpses should be plentiful. White dwarfs, which are formed when sun-like stars balloon into red giants and die, and neutron stars, formed by larger supernovae, can be created early in the lives of these ancient clusters.
Perhaps magnetars can arise when two neutron stars collide and merge, when two white dwarfs collide and merge, or when a white dwarf with an orbiting companion star steals so much mass that it collapses into a newborn neutron star. So far, however, no one has seen a magnetar formed in these ways.
Northwestern University’s Ye thinks we need to look at other ways to possibly form magnetars in these clusters, and to explore how other stars could power fast radio bursts. As well, she says, it's crucial to gather more information about this particular cluster to see what else could be creating the epic blasts.
“Globular clusters are different,” she says. “Some are denser, some are less dense, and in different clusters you will see different outcomes.”
Metzger also notes that it should be possible to generate something that looks like a fast radio burst in the absence of magnetars. Two neutron stars whirling around one another could generate outbursts that resemble fast radio bursts, as could turbulent disks of material swirling around black holes that occasionally produce jets and flares. “I’m a little more inclined to think there’s something other than magnetars going on here,” he says.
Chatterjee agrees, adding that “maybe some fraction of FRBs are not related to magnetars, but are instead related to some sort of black hole jet phenomenon.”
Perhaps fast radio bursts are formed through multiple pathways—kind of like gamma-ray bursts, which confounded astronomers for decades after initially being discovered by a military satellite in the 1960s. Now, we know that both powerful supernovae and colliding neutron stars can produce these immensely energetic flashes of gamma rays.
“Nature found two ways to do that,” Metzger says. “I think we may be seeing something similar with FRBs.”
Read more: www.msn.com/en-us/news/technology/mysterious-radio-burst-from-space-is-unusually-close-and-especially-baffling/ar-AAKrYwC?ocid=msedgdhp
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Post by gus on May 29, 2021 2:43:31 GMT
I would say that there seems to be a dramatic increase in ET activity, we seem to be in some sort of current global peak activity. IMHO if I think hard on the change, I would say that the 2008 Stephenville lights that went past George Bush Jr's Ranch was no coincidence. I do recall UK Navy being buzzed back in 2004 funny now the US released to USS Nimitz 2004 encounter.
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Post by gus on Jun 1, 2021 0:55:34 GMT
More good observations from this guy.
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Post by gus on Jun 5, 2021 0:44:14 GMT
Fark over the USA and nothing is apparently happening. The UAP report to the Senate will apparently say nothing new OMG sooo frustrating.
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Post by gus on Jun 7, 2021 6:19:59 GMT
An amazing find
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Post by gus on Jun 8, 2021 0:53:27 GMT
Doco in 2006! 8:20 3 Western Sub sank due to possible interactions with USOs 29:00 Subs and boats buzzed by USO/UAPs 15th June 1978 and 1979 30:30 Close up photos of UAPs next to ship and in May 1997 33:40 October 1967 1969 Underwater glowing spirals 200 meters to several kms long 35:00 underwater glowing spirals several km long Conclusion ETs own the 7 seas
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