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#time travel is theoretically possible if we travel near light speed
tokiro07 · 17 days
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Latest chapter make me have this theory on speed in UUverse
Aside from Andy and the gods and possibly the Master UMAs/Seal getting sent to Earth, no one in UU has managed to break into faster-than-light travel. Even Top running full-speed in Spring arc only crossed the world in a few minutes and ran 5 laps round the globe in maybe 1 second in the latest chapter, whereas light can travel 7.5 times around Earth in one sec. (Making Top’s speed around 67% light speed)
What if… rather than Top not wanting/is scared to go into lightspeed, he just can’t? My theory is that all those who can go faster than light I mentioned earlier has some sort of spiritual powers that bypass the limit.
From Nico’s spaceship trip visisting Andy to Top running to Victor lauching his arm from orbit down to Earth that one time, all of them are physical actions bounded by physical laws, hence are limited by one that is the speed of photon being the fastest possible speed.
Andy lauching fingers from the Sun to Earth in a matter of seconds and God sending Seal to the planet both have something to do with souls, with what I think has separate laws and doesn’t really obey the lightspeed hard cap.
Maybe I’m just reaching here but it’d be funny to see the Union making a soul spaceship flying faster than photon through space.
I wonder what Rule governs the speed of light; UMA Light? UMA Speed? UMA Stop?
Either way, the limitations of physical mass are definitely at least a property of one of the Rules, though there's a good chance it won't be a Rule we have to worry about fighting
As souls don't have physical mass, it's completely reasonable to assume that they can reach lightspeed, and by the very nature of Unstoppable, Top should be capable of at least approaching lightspeed under normal circumstances, as nothing can stop him. If that's where it caps and he would just keep moving at a constant near-lightspeed, then the addition of the ability to control his soul should theoretically be the extra boost that he needs
Andy once overcame Unmove by using his soul to puppet his body, so there's precedent to believe that the properties of souls allow them to be unbound by most normal logic and then apply those properties to physical objects. He pulled the same trick again when Time desynced his body and soul, eliminating the lag by removing the need for the body to send its own signals
Whether a ship could be moved the same way is hard to say, but I'm certainly not going to assume that there's a limitation that the Negators can't overcome
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Contrary to presentism which denies the realness of anything but the present moment its equally as compelling to consider how the present doesn't actually consist of the present but rather is entirely made of the past. If the past isn't real because you can't observe it anymore then neither is the present moment since after all nothing you see around you is simultaneous with the the moment you experience.
You're surrounded by old light from what once was thats what informs your senses. What actually is right now elsewhere from the point you're at is not till after its already happened the now exists in a superposition of indefinite potentials. Which the hyper empericism of presentism would deny the realness of. But of course you could hand wave this away just by changing your definition of the present.
Consciousness doesn't happen in a single point of space though it must travel across volumes to happen nor is it possible to be conscious in a single instant of a single instant instead consciousness manifests from a continuum of subsequent moments. The concept of an instant maybe isn't even physically meaningful in fact confidently it probably isn't. The experienced now is a stream of time passing by the future becoming the past is the nature of the now you can't extract it from either time without losing it.
If your awareness isn't localized to a single point then where the present is located is uncertain. You must be simultaneous aware of multiple points in space at a single moment which can only interact at the speed of causality and communicate even slower than that. So you're a bit wider than a time cone but you're only able to integrate all of that experiencing together into a coherent whole within its confines.
Beyond all that you've got the almost too simple objection that the details of the structure of the now imply a history which produced it even if you can't directly witness it. The ripples of what happened still linger obviously in how things are now technically theoretically you might even be able to recover that diluted information and trace it back to reconstruct what happened by playing the clock in reverse.
Of course whether that information is ever corrupted into incoherent noise by chaos so completely that it becomes beyond the ability to recover is a significant issue. Logically we can say that we know with near absolute certainty when we see a computer that its existence demands a lengthy tale to explain our now seeing it and so long as the computer exists the memory of that tale still lives on physically embodied within it at least to some extent. If a past event is fully lost to backwards extrapolation it does become an open question whether it ever even happened to begin with.
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kizertalks · 11 months
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Time Travel Explained.
Time travel refers to the hypothetical concept of moving between different points in time, either to the past or the future. The idea is primarily explored in science fiction, but it's also been studied by scientists and philosophers as a thought experiment, looking at the possible implications and effects of time travel.
There are various theoretical discussions and possible models of time travel, including:
- THEORY OF RELATIVITY: Time dilation occurs based on the theory of relativity, which suggests that time moves slower for objects traveling at high speeds or in strong gravitational fields. Therefore, if you were to travel in a spaceship that was traveling close to the speed of light for a certain amount of time, you would return to Earth having only aged a short while, while much more time would have passed for those on Earth.
- WORMHOLES: Wormholes describe a shortcut through spacetime, where one end of a wormhole is fastened in a distant location, and the other end is in the near future or past. In theory, any object that travels through the wormhole would instantly warp to the other end, meaning that time travel could be possible.
While the science behind time travel is still being explored, time travel remains solely a concept, and it is not yet possible to move freely through time as we do through space.
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molsno · 2 years
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🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻🌻
hi breastie did you know that time travel is theoretically possible? if you could bend space enough, you could create a wormhole connecting one location to another such that you can travel between them faster than light. if then you managed to accelerate one end of the wormhole near the speed of light, the flow of time would drastically slow down for it. the math is complicated but for example, if 20 years have passed for the stationary end, then maybe only 5 years will have passed for the moving end. you could bring the moving end to a stop, step through it, and come out of the stationary end 15 years in the future
none of this is possible in practice with the technology we have and we don't even know if wormholes are possible to create in the first place. gravity would also immediately close them unless we filled them with objects of negative mass to repel the force of gravity. and that's shrimply not possible
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'Sudden death' of quantum fluctuations defies current theories of superconductivity
Study challenges the conventional wisdom of superconducting quantum transitions
Princeton physicists have discovered an abrupt change in quantum behavior while experimenting with a three-atom-thin insulator that can be easily switched into a superconductor.
The research promises to enhance our understanding of quantum physics in solids in general and also propel the study of quantum condensed matter physics and superconductivity in potentially new directions. The results were recently published in the scientific journal Nature Physics.
The researchers, led by Sanfeng Wu, assistant professor of physics at Princeton University, found that the sudden cessation (or “death”) of quantum mechanical fluctuations exhibits a series of unique quantum behaviors and properties that appear to lie outside the purview of established theories.
Fluctuations are temporary random changes in the thermodynamic state of a material that is on the verge of undergoing a phase transition. A familiar example of a phase transition is the melting of ice to water. The Princeton experiment investigated fluctuations that occur in a superconductor at temperatures close to absolute zero.
“What we found, by directly looking at quantum fluctuations near the transition, was clear evidence of a new quantum phase transition that disobeys the standard theoretical descriptions known in the field,” said Wu. “Once we understand this phenomenon, we think there is a real possibility for an exciting, new theory to emerge.”
Quantum phases and superconductivity
In the physical world, phase transitions occur when a material such as a liquid, gas or solid changes from one state or form to another. But phase transitions occur on the quantum level as well. These occur at temperatures approaching absolute zero (-273.15 degrees Celsius), and involve the continuous tuning of some external parameter, such as pressure or magnetic field, without raising the temperature.
Researchers are particularly interested in how quantum phase transitions occur in superconductors, materials that conduct electricity without resistance. Superconductors can speed up the process of information and form the basis of powerful magnets used in healthcare and transportation.
“How a superconducting phase can be changed to another phase is an intriguing area of study,” said Wu. “And we have been interested in this problem in atomically thin, clean, and single crystalline materials for a while.”
Superconductivity occurs when electrons pair up and flow in unison without resistance and without dissipating energy. Normally, electrons travel through circuits and wires in an erratic manner, jostling each other in a manner that is ultimately inefficient and wastes energy. But in the superconducting state, electrons act in concert in a way that is energy efficient.
Superconductivity has been known since 1911, although how and why it worked remained largely a mystery until 1956, when quantum mechanics began to shed light on the phenomenon. But it has only been in the last decade or so that superconductivity has been studied in clean, atomically thin two-dimensional materials. Indeed, for a long time, it was believed that superconductivity was impossible in a two-dimensional world.
“This came about because, as you go to lower dimensions, fluctuations become so strong that they ‘kill’ any possibility of superconductivity,” said N. Phuan Ong, the Eugene Higgins Professor of Physics at Princeton University and an author of the paper. 
The main way fluctuations destroy two-dimensional superconductivity is by the spontaneous emergence of what is called a quantum vortex (plural: vortices). Each vortex resembles a tiny whirlpool composed of a microscopic strand of magnetic field trapped inside a swirling electron current. When the sample is raised above a certain temperature, vortices spontaneously appear in pairs: vortices and anti-vortices. Their rapid motion destroys the superconducting state. “A vortex is like a whirlpool,” said Ong. “They are quantum versions of the eddy seen when you drain a bathtub.”
Physicists now know that superconductivity in ultrathin films does exist below a certain critical temperature known as the BKT transition, named after the condensed matter physicists Vadim Berezinskii, John Kosterlitz and David Thouless. The latter two shared the Nobel Prize in physics in 2016 with Princeton physicist F. Duncan Haldane, the Sherman Fairchild University Professor of Physics. The BKT theory is widely regarded as a successful description of how quantum vortices proliferate in two-dimensional superconductors and destroy the superconductivity. The theory applies when the superconducting transition is induced by warming up the sample. 
The current experiment
The question of how two-dimensional superconductivity can be destroyed without raising the temperature is an active area of research in the fields of superconductivity and phase transitions. At temperatures close to absolute zero, a quantum transition is induced by quantum fluctuations. In this scenario the transition is distinct from the temperature-driven BKT transition.
The researchers began with a bulk crystal of tungsten ditelluride (WTe2), which is classified as a layered semi-metal. The researchers began by converting the tungsten ditelluride into a two-dimensional material by increasingly exfoliating, or peeling, the material down to a single, atom-thin layer. At this level of thinness, the material behaves as a very strong insulator, which means its electrons have limited motion and hence cannot conduct electricity. Amazingly, the researchers found that the material exhibits a host of novel quantum behaviors, such as switching between insulating and superconducting phases. They were able to control this switching behavior by building a device that functions just like an “on and off” switch.
But this was only the first step. The researchers next subjected the material to two important conditions. The first thing they did was cool the tungsten ditelluride down to exceptionally low temperatures, roughly 50 milliKelvin (mK).
Fifty millikelvins is -273.10 degrees Celsius (or -459.58 degrees Fahrenheit), an incredibly low temperature at which quantum mechanical effects are dominant.
The researchers then converted the material from an insulator into a superconductor by introducing some extra electrons to the material. It did not take much voltage to achieve the superconducting state. “Just a tiny amount of gate voltage can change the material from an insulator to a superconductor,” said Tiancheng Song, a postdoctoral researcher in physics and the lead author of the paper. “This is really a remarkable effect.”
The researchers found that they could precisely control the properties of superconductivity by adjusting the density of electrons in the material via the gate voltage. At a critical electron density, the quantum vortices rapidly proliferate and destroy the superconductivity, prompting the quantum phase transition to occur.
To detect the presence of these quantum vortices, the researchers created a tiny temperature gradient on the sample, making one side of the tungsten ditelluride slightly warmer than the other. “Vortices seek the cooler edge,” said Ong. “In the temperature gradient, all vortices in the sample drift to the cooler part, so what you have created is a river of vortices flowing from the warmer to the cooler part.”
The flow of vortices generates a detectable voltage signal in a superconductor. This is due to an effect named after Nobel Prize-winning physicist Brian Josephson, whose theory predicts that whenever a stream of vortices crosses a line drawn between two electrical contacts, they generate a weak transverse voltage, which can be detected by a nano-volt meter.
“We can verify that is the Josephson effect; if you reverse the magnetic field, the detected voltage reverses,” said Ong. 
“This is a very specific signature of a vortex current,” added Wu. “The direct detection of these moving vortices gives us an experimental tool to measure quantum fluctuations in the sample, which is otherwise difficult to achieve.”
Surprising quantum phenomena
Once the authors were able to measure these quantum fluctuations, they discovered a series of unexpected phenomena. The first surprise was the remarkable robustness of the vortices. The experiment demonstrated that these vortices persist to much higher temperatures and magnetic fields than expected. They survive at temperatures and fields well above the superconducting phase, in the resistive phase of the material.
A second major surprise is that the vortex signal abruptly disappeared when the electron density was tuned just below the critical value at which the quantum phase transition of the superconducting state occurs. At this critical value of electron density, which the researchers call the quantum critical point (QCP) that represents a point at zero temperature in a phase diagram, quantum fluctuations drive the phase transition.
“We expected to see strong fluctuations persist below the critical electron density on the non-superconducting side, just like the strong fluctuations seen well above the BKT transition temperature,” said Wu. “Yet, what we found was that the vortex signals ‘suddenly’ vanish the moment the critical electron density is crossed. And this was a shock. We can’t explain at all this observation — the ‘sudden death’ of the fluctuations.”
Ong added, “In other words, we’ve discovered a new type of quantum critical point, but we don’t understand it.”
In the field of condensed matter physics, there are currently two established theories that explain phase transitions of a superconductor, the Ginzburg-Landau theory and the BKT theory. However, the researchers found that neither of these theories explain the observed phenomena.
“We need a new theory to describe what is going on in this case,” said Wu, “and that’s something we hope to address in future works, both theoretically and experimentally.” 
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rametarin · 11 months
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Questions I don’t have the knowledge or means to answer.
I was thinking about atomic clocks and pondering, just what could be the theoretical most accurate version of an atomic clock that material science could produce?
To my very limited understanding, it has something to do with the rate of pulses which are produced when atoms and molecules decay and the frequency of that. Some even flickering to the trillions of times per second.
That got me wondering how we define the second. Right now the standard is X-many pulses of a caesium atom, or something like that. Why caesium? Something to do with how accurate we can measure the pulses.
But what if we wanted the most accurate universal standard for a single quanta of time and movement over the space of a window of time? What natural force would be the most idea to compare something to in nature? We use the speed of light to estimate how fast the smallest units of matter are decaying.
If we wanted to measure the smallest interval of time based on the rate at which atoms decay, our standard would need to be the one which is the closest to ‘decays and dissipates at near light speed’. Then measure how many ticks of that equal a second. That should equate a standard unit, and everything after that whether it be an anthropocentric unit or a macrocentric scale, would be exponentials of that.
This is bottlenecked by tools and technology’s ability to simply monitor this rate of humming, but ideally, the best atomic clocks would accurately measure the rate of decay in the one that chirps more times per second. So we have the smallest possible interval between pulses.
Even still, perhaps it’s my own ignorance, but I can’t help but feel there’s a certain circular logic to using some natural constants we can measure but only if we understand the constants of the other universal constants to do so. Inescapable failure of living in an imperfect, decaying universe, I suppose. How far is something? We measure it by the distance light travels over time. How do we measure light? We estimate the distance based on time. How do we measure time? We measure the intervals of decay, using light.
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verydeerbeard · 2 years
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A Guide to the Omniverse. Part 1
By Aleatony / Alexander Maximus Randomness.
The omniverse, the collective of everything that did and didn't, does and doesn't, will and won't, can and can't, must and mustn't, exist.
The uncountable infinity of all and every possible iteration on the existence of anything no matter if it's life, object, both, or none.
This mere concept raises the question, if every possibility exists, then there should be an infinite number of worlds where this theory will seem false, an infinite number of worlds where the concept of omniverse doesn't exist.
Let's put ourselves in perspective. It is wildly known in the Multiverse theory, which states that our actions change the future of the universe, albeit slightly. In an Omniverse theory, a multiverse will be a cluster of universes all coming from a primal one. Within the cluster every universe is in a possible state, the number of states is dictated by the laws that govern that primal universe, and its derivates. In other words, all the universes in the same cluster will have a number of things in common, like a theme of sorts.
With that in mind, to an underdeveloped universe, separated from the others, while still in reach of the same cluster, it will seem that the theory isn't true, hence existing in the omniverse an infinite number of universes where the omniverse theory seems false.
Now, in order to give coherence to the whole theory, we need something to keep a structure. Otherwise, the whole omniverse and its clusters will mix in a chaotic mess unsuitable for any life.
Luckily for us there is a theory that says that, given an enough quantity of information, space and time, intelligence should emerge from it. And given the omniverse characteristics, this sholuld be true in a veritable amount of universes and/or clusters.
The result of this law theoretically should be a universe/cluster, that contains the organized and limitless amount of information about the whole omniverse, and within it a complete intelligence of enough caliber to keep the omniverse together and structured.
This intelligence should have a medium to interact with the omniverse, a matrix of sorts, it should be efficient in its shape, but inorganic in the matter. Like the mycelium of a fungus, made out of a polymorphic and possibly heterochromatic vitreous compound, that while able to interact with the omniverse, leave almost no trace behind, maybe just some sort of gravitational anomaly, a different distribution rate of normal matter to dark matter, or a different shape in the distribution of the galaxies.
Now, to the scales we are talking about, the speed of light is definitely too slow to work with. This is why moving through such distances will require the creation of Einstein-Rosen bridges to warp the distance enough so the use of near or light-speed travel became viable, although this would only allow displacement through clusters which allows the creation of said bridges.
In a matter of laws, the laws of physics on this universe can be used as a humble tool to know the estimated deviation of other parts of the omniverse.
The rest of the omniverse will have an infinite number of variations of them, even clusters where new laws are added, such as those for things that aren't exactly real in this one like magic and mana, superpowers, or cartoon logic and cartoon physics.
Now to end this we have to talk about information, this is an interesting topic because the information in the omniverse isn't limited by space, matter, speed, or distance, this allows that even shapeless thoughts are represented in some place of the omniverse, allowing an interesting review on the classic problem, which was first the chicken or the egg. In this case, which was first the universe of who might have created you and your universe in their head, or your own universe where you live and exist.
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redviper3570 · 2 years
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“Space… The final frontier. These are the voyages of the starship Enterprise. Its continuing mission, to explore strange new worlds. To seek out new life and new civilisations. To boldly go where no one has gone before.”🚀💫
Space ships with warp drive can travel to any alien planet in a matter of minutes. At its max speed the Enterprise from Star Trek can travel at 9000 times the speed of light. If you think thats fast, the Millennium Falcon from Star Wars can travel at 9 million times the speed of light. By comparison the fastest man made object, the Juno probe orbiting Jupiter travels at a whopping 0.0002 times the speed of light. This is still super fast by earthly standards, 74 km/s. But at this rate it would take 20000 years to reach the neartest star Proxima centuari. If we had warp drive like the Enterprise, we could make a day trip there and back in 9 hours.
Miguel Alcubierre manipulated Einstein’s equations and designed a theoretical way to travel faster than light using dark energy to curve spacetime.Take a spaceship and put a bubble of space around it. If you can compress space infront of the bubble and expand space behind the bubble. Then you can make the bubble of space along with the spaceship move. It would be like riding a wave on a surfboard. Multiple scientists all across the world are working on possibilities of design such a propulsion engine.
In a strange coincidence, the research is gearing up just as humankind nears the fictional date in Star Trek lore when warp drive was invented. According to Star Trek, the warp drive was invented in 2063, when Dr. Zefram Cochrane created a spaceship with a warp drive. His warp speed test flight caught the attention of the Vulcans, who realized Earthlings had developed the technology to travel to distant planets.
These ideas work theoretically. Maybe in the next say 20 years this can become reality. Given enough time and more thought provoking episodes of Star Trek to inspire the next generation of physicists.🚀
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gabagoulie · 3 years
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Sleep is for the weak and the unemployed
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Continuing from my last post about science fictional “hyperspaces” (wow, I think that might be the most viral original post I ever wrote; it’s amazing what being reblogged by @argumate can do for a post!):
As a science fiction writer, these are the features I find attractive about “hyperspace” that incline me to favor it over other explanations for “fast” interstellar communication and travel:
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Hyperspace lets space still feel big. Wormholes/portals and instantaneous “jump drives” tend to make space feel small (though wormholes lend themselves nicely to space outside the wormhole network feeling big and to a feeling of sharp discontinuity between “known” or “civilized” space within the network and “unknown” or “wild” space where the network doesn’t reach). Start-anywhere go-anywhere jump drives without serious limitations have the additional issue that they’re more-or-less equivalent to teleporters, so they create the ultimate MAD setting where defending multiple fixed locations from a peer adversary is very difficult, and they minimize the strategic advantages of sustainable stationary banditry over unsustainable hyper-exploitive mobile banditry, and since the likely implications of that are very depressing I prefer to avoid it (except maybe if I was deliberately setting out to write a dystopia or explore the idea).
I want space to feel big in my writing, to give the reader some feeling of the vastness, grandeur, and inhuman scale of the universe. For my main science fiction setting, I think I’ll give hyperspace travel an effective “speed” of something like 5-10 c in Sol’s local neighborhood. That way interstellar journeys are more manageable than they’d be with journeys through our space, but journeys to other inhabited solar systems usually take at least a year or two (Sol to Alpha Centauri may be less than a year in hyperspace, but add in travel time to and from the Sol and Alpha Centauri hyper-limits, which is probably going to be at least a couple of months for each leg, and it’s probably about a year).
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Hyperspace feels more like the sort of thing that might plausibly be useable to almost hairless apes with near-future-ish technology. With warp drives and wormholes and jump drives and so on I get the niggling feeling that’s the sort of thing you should probably have to be on approximately the level of an Orion’s Arm Archialect to do. Real theoretical warp drive and wormhole proposals tend to involve stuff like exotic forms of matter and energy and very large amounts of energy. Hyperspace would be a natural phenomenon, so it’s easier to explain it in terms of people exploiting natural phenomena we just don’t know about now, no weirder than being able to travel faster than rowing would allow by building a sail to catch the wind.
You can say that there are some rare atoms that naturally have a structure that extends into hyperspace. With human senses and 2020s technology they just look like ordinary atoms of silicon, iron, etc., but with the right kind of machinery you can detect them, sift them out of the surrounding 3D atoms, and concentrate them. Once you’ve got enough of them, you can make them the core of a pair of transmitters that you can use to send and receive radio messages through hyperspace. With more energy, you can “push” on these structures and “push” those atoms into hyperspace, and then if those atoms are part of a larger solid object the rest of the object and anything touching it gets dragged along with them (with a certain size limit, perhaps related to mass being “pushed” and energy used, so you don’t have to worry about accidentally sending the whole Earth into hyperspace the first time you try this - that’d be one heck of an oops; maybe a later disproven small theoretical possibility of that happening would go down into the history books along with “before they exploded Trinity they were worried it might ignite the atmosphere”); thus you can send a whole ship into hyperspace instead of just information. When you want to leave hyperspace you can reverse the operation and “push” the ship back into our space.
That gives you a nice highly valuable “handwavium” that can be a hook for various plot and worldbuilding points, e.g. there’s not much obvious economic reason to colonize Mars IRL except maybe tourism (anything you could mine there you get more easily from near-Earth asteroids, and it’s too inhospitable to make much sense as a settler colony), but maybe there’s a huge mother lode of these hyperspace-touching atoms somewhere on Mars. These hyperspace-touching atoms would be especially valuable if the process of using them for communication or in hyperdrives “strained” these structures and at some predictable rate caused some of them to “snap,” causing the atoms to become ordinary 3D atoms of silicon or iron or uranium or whatever. Then there’d be a continuous need for (relatively) large amounts of new ones even in a steady-state economy; you couldn’t just keep recycling them and recycling them and just do a little mining to make up for recycling inefficiencies. This would also be an interesting limit on use of hyperspace; using hyperspace radio or doing a hyperjump involves destroying a small amount of a precious resource, so people wouldn’t want to do it frivolously. This might augment that sphere analogy limitation on hyperspace communication I talked about in my other post; even if a hyperspace radio message from Saturn to Earth got there a little ahead of a radio message through our space, you’d probably send a radio message through our space for anything that isn’t time-critical, because the message arriving ten minutes sooner usually just isn’t worth the predictable cost in “snapped” hyperspace-touching atoms.
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Hyperspace would be an environment, so you can do interesting things with it.
Since hyperspace offers a short-cut because it’s more compact than our space, I like to pull on the idea that it’s like our space but in a more compact state, so it’s similar to what our space looked like when the universe was younger and smaller. Going to hyperspace might be a little like time travelling back to a few tens or hundreds of millions of years after the Big Bang, before the first stars formed. The environment of hyperspace might be a little like the inside of a giant molecular cloud, but “warmer” and extremely impoverished in heavy elements. The gas density might be a few thousand to a few billion atoms per cubic centimeter (by comparison, sea level air is about 10^19 molecules per cubic centimeter while the interstellar medium averages around 1 atom per cubic centimeter). The gasses and plasmas in hyperspace would be almost pure hydrogen and helium. The cosmic microwave background temperature in hyperspace might be around 50 K; that’s warm in comparison to what it is in our space (around 3 K), and warm enough to probably be a big part of the reason hyperspace has no stars (present day star-forming giant molecular cloud regions have gas temperatures around 10-20 K), but by human standards it’s deeply cold; it’s upper atmosphere of Uranus temperature. With no stars, I’d guess hyperspace would be a place of more-or-less total darkness outside the range of any lights humans passing through might bring with them.
Alternately, if I want hyperspace to have a murky and mysterious quality and be a place where visibility isn’t good and sensors don’t work well (so a vibe a bit like B5 hyperspace), I could say the Big Bang nucleosynthesis era lasted longer in hyperspace and there produced a substantial amount of heavy elements, some of which then condensed into dust (probably more like smoke if it’s similar to interstellar dust in our space - nanometer to micrometer particles). This dust would probably be pretty insubstantial on human scale distances (again, if it’s like the interstellar medium matter in hyperspace would be about 99% mostly hydrogen and helium gas and plasma and 1% dust, and even a relatively “dense” hyperspace with billions of atoms per cm^3 would have less than a billionth the gas density of sea level air), but over AUs it would scatter light and that effect might add up. This would make hyperspace similar to a dark nebula.
If I want to take the “hyperspace is a scary place” further, I could add sources of energy that might further confuse sensors and add dangerous radiation and other dangers to the mix. Maybe hyperspace has a few large black holes or something, with energetic accretion disks and polar jets fed by all that relatively dense gas and adding turbulence to it. Or maybe spacetime in hyperspace is “lumpier” than spacetime in our space and hyperspace has weird “rivers” formed by something related to whatever force drives cosmic expansion and some of the gas/plasma gets caught in that and accelerated to large fractions of the speed of light and then slams into the low-velocity material in the “still” parts in places, creating lots of turbulence and various other interesting and scary things (powerful magnetic fields, radiation, locally intense heat, maybe some of these collision zones are even giant naturally occurring inertial confinement fusion reactors; maybe that’s where the heavy elements in the dust come from). Maybe hyperspace has a lot of cosmic strings; it makes a certain intuitive sense that, hyperspace being more compact than our space, its cosmic eggshell might be densely veined with cracks.
This gets into another interesting aspect; hyperspace might have something equivalent to terrain; hyperspace travel may be easier in some directions than others. And there’s lots of worldbuilding and plot hooks you could hang from that idea.
For example, let’s look at that idea of hyperspace having “rivers” formed of exotic spacetime structures and filled with gas/plasma streams moving at high fractions of the speed of light. If the edge of these “rivers” has a gradual enough velocity gradient and the plasma in the “rivers” is ionized, with enough skill a spacecraft pilot might be able to catch that “current” with a magsail and ride it, then when they’d gotten about as far as they needed to go they could leave the “river” and do magsail braking against low-velocity plasma in the “still” areas. Just gotta be careful to stay well away from the dangerous collision zones! This might be a huge part of the short-cut offered by hyperspace travel! It could be that distances across hyperspace are only modestly shorter than distances across our space (say, Alpha Centauri is 1 light year away in hyperspace), but the really big savings is you can catch one of these hyperspace “currents” and use it to get up to large fractions of c without expending any fuel. A set-up like that does raise some awkward questions about conservation of energy, but I could say something like “the hyperspace ‘rivers’ are areas where dark energy is being converted into kinetic energy, slightly slowing down the expansion of the universe in the process.” It’s not like we know much about how dark energy works, or even what it is, so for all we know that’s a thing that might happen under certain conditions.
Those collision zones would generate substantial radiation, including light, so unlike a calm hyperspace a turbulent hyperspace with energetic “currents” would probably have light. Don’t know how bright it would be; all that dust (made of heavy elements built up over the eons by inertial confinement fusion in collision zones, I like that idea!) would absorb a lot of light over cosmic distances, and stars are pretty bright but most of our space is pretty dark.
That set-up would make hyperspace travel kind of like sailing; there would be “currents” or “winds” you want to catch, and travel might be a lot faster along directions where the currents are favorable. Travel times in hyperspace might only loosely correlate with distance; Alpha Centauri might take longer to reach than Zeta Reticuli. There would also be hazards you’d need to avoid, e.g. the collision zones.
Maybe part of the explanation for the Fermi Paradox might be that Earth is in the middle of a big “still” part of hyperspace; few ships went here because we’re in the middle of a cosmic doldrums that takes years to crawl across.
With a set-up like this, hyperspace may have “weather” that influences interstellar commerce, and “climate change” on historical timescales that influences the trajectories of interstellar societies. Ages when hyperspace is particularly turbulent might cause Dark Ages as hyperspace travel becomes very dangerous. Ages when hyperspace becomes unusually calm might also cause Dark Ages as there are no fast hyperspace “currents” to ride and hyperspace travel becomes relatively slow. In one age hyperspace “currents” may be arranged such that a world is isolated; a few thousand years later the hyperspace “currents” might have shifted and that previously isolated world might be much more accessible and back in the mainstream of interstellar civilization.
One wrinkle: a turbulent, energetic, opaque hyperspace such as this probably wouldn’t be good for sending radio signals across. Maybe the universe actually has multiple “basement” levels, hyperspace is just the one that’s “closest” to our “living room” level and the only one that’s “close” enough that ships can travel to and from it, but there’s a clearer layer that’s “farther away” but still “close” enough that you can send radio signals through it, and that “deeper” clear layer is the one used for interstellar communication. Bonus idea I like: the deep clear layer is even more compact than hyperspace (by orders of magnitude) so it’s overall a much better short-cut in every way except being “too far away” to send ships through it, so finding a way to send ships through it is a huge potential breakthrough that tantalizes generations of scientists and engineers who so far have not managed to figure out a way to do it.
Really, on that note, I like the idea that the universe is analogous to an onion with many “layers,” and hyperspace and the deep clear layer are just the layers that are most easily accessible from our space. There are a lot of “basements” below the deep clear layer, and generally as you get farther “down” the “basements” get smaller, denser, and hotter; going “down” is a little like time travelling to eras closer and closer to the Big Bang (though this isn’t a completely reliable rule - the deep clear layer is smaller than hyperspace and perhaps warmer, but seems to be a lot emptier; maybe most of its matter has been sucked into black holes?). Maybe the whole thing is a bit timey wimey wibbly wobbly and if you go “down” far enough you eventually hit what 2020s science knows as the moment of the Big Bang. As well as “basements” there are also “attics,” but they’re less accessible because going “up” is harder than going “down.” If going “down” into the basements is a little like time travelling to the early universe, going “up” into the attics is a little like time travelling to the deep future, to places that look kind of like what our space may look like in the deep future black hole era (assuming the Big Rip doesn’t destroy our universe before that deep future proton decay story has time to play out). The “attics” are vast, empty, and deeply cold; cosmic microwave background temperatures a tiny fraction of a degree above absolute zero and precious little else to generate energy, maybe one atom in every cubic kilometer of space. They probably expanded too quickly for stars to ever form there. The total number of layers might be large; maybe hundreds or thousands, maybe billions, maybe a number so big it would need to be expressed in scientific notation. I like this idea because it makes hyperspace feel less implausibly convenient for humans; we’re just taking advantage of a particularly convenient part of a big macrostructure that’s mostly inaccessible to us.
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Hyperspace is a natural phenomenon, so it probably isn’t going to be neatly quarantined to just being a thing humans can use for communication and travel. Hyperspace-related phenomena are going to show up in nature, and this offers a neat explanation for any exotic soft SF-ish natural phenomena you may be interested in incorporating into your setting.
Hyperspace (and other “basements” of our universe) also gives you a built-in parsimonious explanation for any other bits of soft SF technology your setting might feature. Want your setting to have e.g. Star Trek style forcefields? You can say they work through interaction with one of the “basement” layers of the universe.
On that note, I have an idea for a more hard SF version of the Babylon 5 “going beyond the Rim” thing or Stargate ascension, based on the “onion universe” concept I described above, which might serve as a partial explanation for the Fermi Paradox. Maybe some “layers” of the “onion” are “superhabitable” to advanced machine intelligences (though not to primitive flesh and blood beings like us). You know the aestivation hypothesis? If advanced machine intelligences could move to an “attic” they wouldn’t have to wait billions of years for our space to cool down; the cosmic microwave background temperatures in many of the “attics” would already be some tiny fraction of a degree above absolute zero. Maybe they could move to a nice big cold “attic” and live there and “mine” a nice compact “basement” that is rich in matter and energy, getting the best of both worlds. Most of these “attics” and “basements” would be completely inaccessible to humans, but beings with better technology and more resources might be able to access many more of them (or maybe even get beyond the “onion” and search the entire multiverse for universes with conditions more to their liking). So the universe’s most powerful and most enduring civilizations might usually leave our space and move to another “layer” or universe that has conditions more ideal for them, and thus be mostly undetectable to us.
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See: the concept of hyperspace is loaded with potential plot and worldbuilding hooks if you use a little imagination, and I like that!
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uncloseted · 2 years
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Do you think time travel could ever be real?
This is my favorite type of question I get on here. I love the assumption that I know the answer to this, and I also love the fact that now I have an excuse to learn the answer to this. I am actually very familiar with time travel as a philosophical topic. It’s a pretty popular topic within the field of metaphysics- I actually had an entire class at university that was dedicated to it. But up until today I didn’t have a particularly good understanding of the physics side of things (and still don't, really, so take everything I say here with a grain of salt).
So, if we're being pedantic (as every article I read was), we can say that of course time travel is real- we travel in time all day long, since we are always moving forward into the future. But that's obviously not what you meant, and that answer is obnoxious, so let's move more into the sci-fi realm.
The general consensus seems to be that time travel is theoretically possible in the sense that there's no fundamental scientific reason that we know of that would prevent it. But time travel may not look the way we imagine it would and there are significant engineering barriers to making it actually work in practice.
Stephen Hawking had a somewhat sarcastic theory called the "chronology protection conjecture" which stated that "the laws of physics do not allow time machines to keep the world safe for historians." He said that the greatest argument for time travel not being possible is that there aren't any time tourists from the future. The more academic reasons for time travel not being possible can be intensely metaphysical, but for now I'll skip the discussion of four-dimensional spacetime worms and just say that these issues tend to have to do with paradoxes.
Traveling to the Future
Traveling to the future is pretty well-established as something that’s possible and, in a way, something we can already do. Albert Einstein's theory of special relativity proposes that time is an illusion that moves relative to the observer, and so an observer traveling near the speed of light will experience time differently than someone who is standing still. Basically, the faster you're moving, the slower you experience time. This is called "time dilation", and it's why an astronaut who goes into space will have aged ever so slightly less than their twin who stays on Earth (an astronaut who has been on the International Space Station for six months will have aged about .005 seconds less than someone on earth). So in a sense, time travel does already exist; it’s just not very impressive. However, if you were in a spaceship traveling at 90% the speed of light, you would experience time passing about 2.6 times slower than on Earth. So if you took a trip at 90% of light speed to a point 10 light years away, when you returned home, you would be almost 9 years older, but everyone on earth would have aged 22 years. In this scenario, you've essentially traveled 11 years into the future.
Black holes may also facilitate time-travel using this same general principle of time dilation. Black holes are incredibly dense, and the more gravity that affects an object, the faster time moves around it. So in theory, you could get close to the black hole, wait a short amount of time, and then move away from it once you're at the point in the future that you want to be. The drawback here is that there isn't a way to go back to your "original" time; you'd just be stuck in the future. Plus, if you got too close to the event horizon of the black hole, you wouldn't be able to escape it. If you're seen the movie Interstellar, they use this principle- the astronauts visit a planet where an hour on the planet is the equivalent of seven years on Earth.
Traveling to the Past
Time travel to the past is significantly more complicated, in part because it brings up issues of causality and can cause paradoxes. However, theoretical ways time travel to the past could work have been proposed.
Time travel into the past requires what’s called a “closed timelike curve”- a closed loop in spacetime that allows an object to return to its own past:
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The most common theories about how time travel to the past may be possible center around wormholes as the method by which a person traverses the “closed timelike curve”. Wormholes are kind of like shortcuts through spacetime- my understanding is that they work kind of like the "tesseract" in the book A Wrinkle in Time.
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Hypothetically, one could use a wormhole to travel through spacetime to bridge large distances or to travel to different points in time. Making a wormhole human-sized would require a huge amount of energy, but it’s not impossible. This type of wormhole is called a “traversable wormhole”.
There are two hypothesized methods for creating a "traversable wormhole". The first would be to take one end of the wormhole, accelerate it to close to the speed of light, and then to bring it back to the origin point. Because of time dilation, the accelerated wormhole entrance would age faster than the other entrance, and the unaccelerated entrance would essentially be in the past.
The second possibility requires one end of the wormhole to be placed within the gravitational field of a black hole and then returned to a position near the other entrance. That would create time dilation around the wormhole that was placed near the gravitational field of the black hole, again making it “older” than the other entrance and allowing time travel to be possible. Basically, you’re putting one wormhole entrance in the future (using the same methods that we used to put a person in the future in the examples above) so that you can then travel back to the time the other entrance was made.
This type of wormhole would only allow a person to travel back in time to when the wormhole was created; you wouldn’t be able to go further back in time than that. Some physicists believe that wormholes pop into and out of existence all the time on the quantum scale. But so far, we haven't seen any proof of wormholes existing, which is thought to be due to incompatibility between general relativity and quantum mechanics.
This is where it gets tricky (or trickier than it already was). Basically, quantum mechanics showed up and was like, “bitch, you thought”, and so we had to rework the way we understand physics. My understanding of quantum physics is even fuzzier than my understanding of general relativity (although I did read a bunch about it for this post), so again, grain of salt on this. But basically, quantum mechanics helps us to solve some of the paradoxes that are present within time travel. For example, some quantum physicists theorize that quantum mechanics would satisfactorily deal with the Grandfather Paradox by having the time traveller enter a parallel universe. Theoretically, this allows them to be in a state of “quantum superposition” where the time traveler simultaneously does and does not exist. I don't really understand the implications of quantum mechanics on methods of time travel, but suffice to say that it may open up other possibilities.
There’s a pretty good video featuring Neil deGrasse Tyson that breaks time travel down here and offers some possible theories for how time travel may be possible:
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And this is another video I found helpful:
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seeker-of-the-stars · 3 years
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Spoilers for MTMTE 48 onward—mayhaps Skids ending up in TFP with the bots during the Sunder issuess somehow and not dying?
This has been in my inbox for like, weeks now cause I needed to catch up on the comics (Just finished issue 49 last night lol) so I’m sorry you had to wait so long. But yes, I’d be happy to!
***
“What happened? Where am I?” Skids cried out. He looked around and saw that he was in the middle of a desert. 
“Hello? Rung? Rodimus? Is anybody here?” All he got in answer was silence, and he felt his vents kick up speed.
“Stay calm Skids, this has to be another one of Sunder’s mind tricks,” he took a seat on the ground, concentrating on every detail around him. The heat of the ground, the color of the sky, the barest hint of the smell of energon in the air...
“Cybertronians,” he whispered to himself. “They’re here, or they’ve been here recently. If I can find them, then maybe I can pull myself out of this.”
He continued to look around his immediate area for other clues, signs of Cybertronian life. He stopped when he saw tire tracks on the ground; ones that broke off in various different places and were replaced with pedeprints too big to belong to any other life forms.
“Bingo,” he grinned to himself.
***
“So let me get this straight,” the bot who called himself Ratchet said. He handed him an energon cube as he continued to speak. “You found our top secret base, completely hidden away from civilization all by yourself?”
“It’s easy once you know what to look for,” Skids said, sipping on the energon. “Well, not necessarily “easy.” It took me all night, with multiple false trails to find you. But man am I glad I did cause my fuel tanks were about to give out.”
“And you think this is all part of a memory you repressed?” Optimus asked. Like Ratchet, Optimus looked similar to the bot he knew in real life, but there was still something... different.
“Must be something like that,” Skids said. “I don’t think I’ve ever been anywhere like this, and you guys are a lot different than the bots I knew, but I don’t have any other explanation for what’s happened. Unless Sunder is capable of more than bringing up old memories.”
Optimus and Ratchet exchanged a glance. “I think you might feel better with some rest, my friend.”
Skids narrowed his optics. “You think I’m crazy, don’t you?”
“Of course not. It’s just that a lot of the information you gave us, the names of your friends, the Lost Light, the Knights of Cybertron... they don’t exist.”
“You might have hit your head at some point,” Ratchet offered. “We think that you’re one of the bots from the colonies who somehow made your way to Earth and crash landed. We have Arcee, Bulkhead, and Bumblebee out there looking to see if they can find the rest of your crew.”
“No, you don’t understand!” Skids said. “We didn’t crash, and I didn’t hit my head. We weren’t even anywhere near Earth. My crew members are still under attack from that... that psychopath and they’ll all die if I don’t get out of here and help them!”
“Please, Skids,” Optimus said. “We know this is hard for you. Just let Ratchet run some tests and get some recharge, and we can all talk about this later.”
“But-” 
“Optimus is right. You won’t be any good to your crew until we figure out what’s going on and how to help. And you really could use some rest.”
Skids sighed. “Fine. Just make it quick.”
***
“I don’t get it, Optimus,” Ratchet said. He was looking over Skids’ health report, shaking his helm. “No head injuries, no short circuiting, nothing physical that could’ve possibly caused him to suffer from delusions.”
“Maybe the cause isn’t physical, then,” Optimus said. “We do not know the state in which the colonies are in anymore, it’s been millennia since we’ve seen them. Maybe something happened there and his mind is making up stories in order to protect itself from further harm.”
“Ordinarily I might agree with you, but look,” Ratchet pointed to the diagram of Skids on his datapad.
“I’m... afraid I don’t understand what you mean.”
“His circuitry is completely different from anything I’ve ever seen on another Cybertronian,” Ratchet said. “Not to mention there are traces of radiation in his energon that he only could’ve gotten from... Primus, I feel ridiculous for even saying it.”
“What is it, old friend?”
Ratchet sighed. “Have you ever heard multiverse travel, Optimus?”
***
“So what you’re telling me,” Skids said. “Is that you think I traveled here from an alternate universe?”
“In layman’s terms, yes,” Ratchet said. “It is theoretically possible to do, but no one has ever done it successfully. But I have been a scientist since before the war started and I think Wheeljack and I might be able to create a portal to get you home. You must be warned that it will take some time, though.”
Skids forced a smile. “Thank you, Ratchet, it means a lot. If you need any help, I’d be more than willing to lend a servo.”
“Thank you,” Ratchet said. “I’m sure we’ll need all the help we can get.”
As Ratchet walked out and left Skids by himself, he thought back to his crew on the Lost Light. He wanted nothing more than to go back to them and make sure they were all safe, but he had to wonder if there would even be ship left by the time he got there.
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felicityzhang · 2 years
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Warp drives: Physicists give chances of faster-than-light space travel a boost
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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?
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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.
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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.
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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.
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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.
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mysticstronomy · 4 years
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HOW WILL THE UNIVERSE END??
Blog #21                                                  Wednesday, September 23th, 2020
Welcome back,
Cosmology deals with the big questions of the universe, often the same question that keep philosophers up at night. When did the universe begin? How did start? Has the universe always been expanding? (For the record, the answers are: about 13.8 billion years ago, in a high – density state that rapidly expanded called the Big Bang and yes, but not always at the same speed.) But here’s a question they haven’t figured out yet:  How’s it all going to end?
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It’s a big question all right, but we’ve made surprising headway toward an answer. In the last years of the 20th century, the astrophysical community was stunned to learn that the universe was driving itself apart. For decades, scientists had known that distant galaxies all move away from us, with the farther ones moving fastest. The only way this makes sense is if the universe itself is expanding. But when cosmos, the force of gravity should be slowing down that expansion. But when cosmologists calculated just how much it’s slowed down, they got a negative result – the expansion of the universe is speeding up!!
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Nobody knows what’s driving the acceleration, so cosmologists have dubbed that mystery dark energy. It is so dominant (about 69% the total content of the entire cosmos) that dark energy quickly become a part of any discussions about the final end of the universe. And while there are no definite answers yet, those discussions have come up with a few interesting possibilities.
1. THE BIG RIP
It started with a Big Bang and it'll end with a Big Rip. Maybe. Everything we know, and everything else besides, burst into existence at the Big Bang. Now scientists have concluded that we could be heading for an equally dramatic cosmic finale: the Big Rip. There’s no need for immediate alarm, however: the extreme sequence of events is predicted for around 22 billion years from now. Dr Marcelo Disconzi, the mathematician who led the work at Vanderbilt University in Tennessee, said: “The idea of the Big Rip is that eventually even the constituents of matter would start separating from each other. You’d be seeing all the atoms being ripped apart ... it’s fair to say that it’s a dramatic scenario.”
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Scientists are now fairly convinced that the universe began with the Big Bang, around 13.8 billion years ago – starting at a pinpoint of incredibly high density and expanding to what we have today. A new theoretical model suggests that as the universe expands, everything, from galaxies, planets and atomic particles to space-time itself, will eventually be torn apart before vanishing from view.
Disconzi's hypothesis is based on existing theories about dark energy, a largely theoretical substance thought to make up 70 percent of the universe's mass. For a Big Rip to occur, dark energy must win in its battle with gravity to such a point where it can rip apart individual atoms. He began by looking at the stickiness of the universe -- or how resistant it is to expansion and contraction. So-called cosmological viscosity is different to the viscosity of something like ketchup, which is measured by how quickly a liquid can move through a small opening.
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Disconzi linked his theory of cosmological viscosity to the Big Rip, which was first hypothesized in 2003, by looking at what happens to the motion of fluids in supernovae and neutron stars. His breakthrough was in coming up with a theory that explained what happened when sticky fluids traveled at near light speed. Previous models had confusing results, with one even suggesting that fluids would travel faster than the speed of light.
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The new evidence suggests that the expansion of the universe will eventually become infinite. The supposition relies on two big leaps about the behavior of dark energy now and in the distant future. Previous models largely ignored viscosity, but in Disconzi's hypothesis it is viscosity of the universe that drives its violent destruction. His theory is based on proposals made by French mathematician André Lichnerowicz in the 1950s.
2. THE BIG FREEZE ……..
COMING UP!!!
(Saturday, September 26th, 2020)
“HOW WILL THE UNIVERSE END?? PT.2”
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Astronomers capture formation of a powerful cosmic jet
Using a network of radio telescopes on Earth and in space, astronomers have captured the most detailed view ever of a jet of plasma from a supermassive black hole. The jet travels at nearly the speed of light and shows complex, twisted patterns near its source. These patterns challenge the standard theory that has been used for 40 years to explain how these jets form and change over time.
A major contribution to the observations was made possible by the Max Planck Institute for Radio Astronomy in Bonn, Germany, where the data from all participating telescopes were combined to create a virtual telescope with an effective diameter of about 100,000 kilometers.
Blazars are the brightest and most powerful sources of electromagnetic radiation in the cosmos. They are a subclass of active galactic nuclei comprising galaxies with a central supermassive black hole accreting matter from a surrounding disk. About 10% of active galactic nuclei, classified as quasars, produce relativistic plasma jets.
Blazars belong to a small fraction of quasars in which we can see these jets pointing almost directly at the observer. Recently, a team of researchers including scientists from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, Germany, has imaged the innermost region of the jet in the blazar 3C 279 at an unprecedented angular resolution and detected remarkably regular helical filaments which may require a revision of the theoretical models used until now for explaining the processes by which jets are produced in active galaxies.
"Thanks to RadioAstron, the space mission for which the orbiting radio telescope reached distances as far away as the moon, and a network of twenty-three radio telescopes distributed across the Earth, we have obtained the highest-resolution image of the interior of a blazar to date, allowing us to observe the internal structure of the jet in such detail for the first time," says Antonio Fuentes, a researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC) in Granada, Spain, leading the work.
The new window on the universe opened by the RadioAstron mission has revealed new details in the plasma jet of 3C 279, a blazar with a supermassive black hole at its core. The jet has at least two twisted filaments of plasma extending more than 570 light-years from the center.
"This is the first time we have seen such filaments so close to the jet's origin, and they tell us more about how the black hole shapes the plasma. The inner jet was also observed by two other telescopes, the GMVA and the EHT, at much shorter wavelengths (3.5 mm and 1.3 mm), but they were unable to detect the filamentary shapes because they were too faint and too large for this resolution," says Eduardo Ros, a member of the research team and European scheduler of the GMVA.
"This shows how different telescopes can reveal different features of the same object," he adds.
The jets of plasma coming from blazars are not really straight and uniform. They show twists and turns that show how the plasma is affected by the forces around the black hole. The astronomers studying these twists in 3C 279, called helical filaments, found that they were caused by instabilities developing in the jet plasma.
In the process, they also realized that the old theory they had used to explain how the jets changed over time no longer worked.
Hence, new theoretical models are needed that can explain how such helical filaments form and evolve so close to the jet origin. This is a great challenge, but also a great opportunity to learn more about these amazing cosmic phenomena.
"One particularly intriguing aspect arising from our results is that they suggest the presence of a helical magnetic field that confines the jet," says Guang-Yao Zhao, presently affiliated to the MPIfR and member of the scientists team. "Therefore, it could be the magnetic field, which rotates clockwise around the jet in 3C 279, that directs and guides the jet's plasma moving at a speed of 0.997 times the speed of light."
"Similar helical filaments were observed in extragalactic jets before, but on much larger scales where they are believed to result from different parts of the flow moving at different speeds and shearing against each other," adds Andrei Lobanov, another MPIfR scientist in the researchers team. "With this study, we are entering an entirely novel terrain in which these filaments can be actually connected to the most intricate processes in the immediate vicinity of the black hole producing the jet."
The study of the inner jet in 3C 279, now featured in the latest issue of Nature Astronomy, extends the ongoing strive to understand better the role of magnetic fields in the initial formation of relativistic outflows from active galactic nuclei. It stresses the numerous remaining challenges for the current theoretical modeling of these processes and demonstrates the need for further improvement of radio astronomical instruments and techniques which offer the unique opportunity for imaging distant cosmic objects at a record angular resolution.
Using a special technique called Very Long Baseline Interferometry (VLBI), a virtual telescope with an effective diameter equal to the maximum separation between the antennas involved in an observation is created by combining and correlating data from different radio observatories.
RadioAstron project scientist Yuri Kovalev, now at the MPIfR, emphasizes the importance of healthy international collaboration to achieve such results: "Observatories from twelve countries have been synchronized with the space antenna using hydrogen clocks, forming a virtual telescope the size of the distance to the moon."
Anton Zensus, director of the MPIfR and one of the driving forces behind the RadioAstron mission over the last two decades, states, "The experiments with RADIOASTRON that led to images like these for the quasar 3C 279 are exceptional achievements possible through international scientific collaboration of observatories and scientists in many countries. The mission took decades of joint planning before the satellite's launch. Making the actual images became possible by connecting large telescopes on the ground like Effelsberg and by a careful analysis of the data in our VLBI correlation center in Bonn."
IMAGE....The filamentary structure of the jet in 3C 279 revealed by RadioAstron. a, Total intensity (left) and linearly polarized (right) RadioAstron image at 1.3 cm obtained on 10 March 2014. While both images in a show brightness temperature (color scale), the image on the right also shows the recovered electric vector position angles overlaid as ticks. Their length and color are proportional to the level of linearly polarized intensity and fractional polarization, respectively. b, The 1:1 scale 1.3 mm EHT image obtained in April 2017. Contours correspond to our RadioAstron image, and are shown to compare the different scales probed. These start at 90% of the peak brightness and decrease by successive factors of 3/2 until they reach 5%. Both images were aligned with respect to the pixel with maximum brightness. c, The 7 mm VLBA-BU-BLAZAR program image obtained on 25 February 2014. White ellipses at the bottom-left corners of b and c indicate the 20 × 20 μas2 and 150 × 360 μas2 convolving beams, respectively. The color bars refer only to information displayed in a. Credit: https://www.nature.com/articles/s41550-023-02105-7
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fae-fucker · 3 years
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Review: Death Wind by Tara Grayce
Essie should be planning her happily ever after, not planning a war. Although they once were enemies, the humans of Escarland and the elves of Tarenhiel have allied to fight the trolls from the far north. But alliances are tricky things even in the best of times, and with Farrendel, the elves’ foremost warrior and Essie’s husband, captured by the trolls, the circumstances appear dire indeed. But Essie won’t give up, and she will make her two peoples work together to fight this war if it’s the last thing she does. One way or another, she will get Farrendel back, no matter what it takes.
Gonna be honest, didn't expect much given my lukewarm reaction to the previous two books, but this one? This one actually held my attention for genuine reasons rather than just being a light read. Because the plot involves a lot of conflict (arguably the biggest conflict possible, war), the pacing is steady, and two of the three POV characters are mostly suffering and/or being tortured, there's actually tension for once. It's a welcome change, and proves that the author is very much capable of writing it but just chooses not to in favor of boring and conflict-free family interactions.
With Melantha introduced as a POV character, we're offered a pretty buckwild concept for this series: a character that makes mistakes and has to live with the consequences. I actually found myself liking Melantha, not because I thought she was a compelling character (she wasn't) or because I felt bad for her (I didn't), but because she had what Essie didn't: flaws. There's even a point in the book where Melantha thinks about how much she dislikes Essie because Essie is so sugary perfect and everything Melantha wishes she could be, and I think it's supposed to show us how bitter and insecure Melantha is? Except she's 100% correct, Essie is literally too perfect to be a real person and I just sat there going "yeah, you're right, and don't feel bad for being shitty because literally nobody can actually be like Essie."
However, Melantha suffers from Stupid Bitch Syndrome, which doesn't exactly make for a good protagonist/POV character. She's not intended to be dumb, the book expects us to think she was simply misguided and bitter and not, like, a complete idiot who should've known better. But her instant remorse feels less like character development and more like her suddenly realizing she’s actually a huge idiot who fell for the enemy’s nonsense, which she is. She's supposed to be an older elf, a grown woman, yet she makes such an obvious mistake and immediately regrets it and folds like a wet blanket the moment shit hits the fan. It's honestly a bit pathetic. The only reason I preferred her over Essie was because she introduced some much-needed depth to the character roster, but that depth was still about the size of a teacup, compared to Farrendel's thimble and Essie's singular water molecule. Her relationship with the troll prince was actually ... interesting? It was all mostly unspoken, which I think made it stronger than the overly telegraphed thing Essie and Farrendel have going on, and I’m sure it’ll be flattened out and become boring in the next book, so enjoy this potential before it’s wasted.
Farrendel spends the entire book being tortured and thinking about how he's being tortured. I can't blame him, but it doesn't make for good reading. I honestly think his POV could've been left out altogether and it wouldn't have changed much. Melantha is already there with him letting the reader know he’s suffering, we don’t need two POVs telling us the same thing. Oh uh, except for the part where he ... puts his magic in a soul-bond pocket. I'd mark this as spoilers but it's literally on the cover. I guess if his POV was removed then we'd never know how Essie learned to blast his power in battle at that one convenient moment, but it barely affects the plot afterward so um, yeah. I'm having a hard time justifying his POV at all. I'm still not over that part btw, how Farrendel just ... makes a "mental fist" (no, really), grabs his magic in one and his soul bond with Essie in the other and just puts them together like he's connecting two cables to an adapter. And he knew to do this ... how? It's not like we've seen him experiment with his magic before, in fact he's been shown to hate it and only use it when necessary, but apparently this tortured and exhausted man has the presence of mind to try something as vague and theoretical as ... putting his magic in a soul pocket. He spends a few pages going “I wonder if I can do this” and then it works on the first try. He does consider whether it’ll hurt Essie and decides not to try it, but as I said, he does it soon after anyway so like ... I don’t think it’s supposed to be funny or show how little of a shit he gives about Essie, but that’s sort of the implication and I thought it was funny as hell. 
Anyway, the magic pocket is about as much worldbuilding/lore as we get from this series entry, aside from the trolls having their own political intricacies and tensions, which I’m assuming the next book will expand upon. The writing itself in this book was pretty bad at times. The repetition of certain words and names was really glaring in some parts and felt amateurish. Take a shot every time the word “magic” appears and you’ll be in the grave before the book ends. Prince Rharreth and King Charvod are almost always referred to with their full titles and names for some reason? A few editing rounds would’ve helped this a lot, methinks.
The plot is mostly moved along in Essie’s POV, which is slightly less insufferable than usual because she’s the one observing the movement of the two armies and there are actually action scenes in there that, while don’t exactly made me worried about her (there’s no way this perfect idiot will ever die), still provided some tension. But it’s honestly not much, the “war” lasted two entire weeks (and that’s including the strategy, logistics, and mobilizing) and with how fast the armies travel and how little resistance they face (and how Deus Ex Farrendel-d the final battle was, the guy is apparently full of godlike destructive power despite being starved and tortured, go off king), it all felt very unrealistic and easy. Like, we have two armies marching in the middle of a mountain chain during magical snow storms, all while being regularly assaulted by the defending army, and they still get there no problem, without a single mention of soldiers struggling not to die of exposure. Aight. I guess these elves and humans are just very resistant to the cold, for some reason.
I have a sneaking suspicion that the reason it goes over so fast in-universe is because the author wanted Farrendel to be horribly tortured throughout his captivity, but also knew that if that lasts too long, the damage will be too severe to easily resolve in the next book. But instead of easing off the hardcore torture, because then we’d lose out on that drama and those High Stakes, she decided to speed up the whole war thing, because hey, who cares about that, anyway? We just want Farrendel back, right? Riiiight? Better hurry up guys! Don’t want Farrendel to be too tortured to fix with some strawberry-flavored medicine and vague counseling in the next book!
So yeah, the plot moves on speedily, but at what cost? Mainly depth. Again. And once again, Essie suffers the most from being a bland caricature of a person and dragging the whole thing down. The author’s GR bio says she writes “spunky and tough” leading ladies, and I guess having no other things in your brain except sparkly kitten gifs is a certain kind of toughness in an “immovable object” sort of way, but “spunk” implies a of counter-culture edge that sweet widdle Essie simply does not have.
There was one small section where Essie felt bad over how the human and elven warriors were going to die, how many mothers and sisters and daughters would suffer just so she didn’t have to, but then we don’t find out the death count, the casualties are never even mentioned, and Essie moves on from this without even a single thought questioning the morality of a monarchy or her own position of power. Now, I get that that’s not the focus of this series, but it just adds to how Essie’s worries are always surface-level and never justified by the plot, how she never has to do any introspection and is never allowed to not always be annoyingly positive. Whenever she even begins to think something negative, she instantly, almost compulsively changes trajectory and just decides not to worry about it, and then it never comes up again anyway. This would’ve been like, an interesting take on toxic positivity and how Essie represses her own emotions, but no, the book never goes there, she’s just that perfect and wee and optimistic, even during a war and when her husband’s being tortured to near-death. It’s kind of insulting to read, honestly.
Oh yeah, that’s another thing that annoyed me. Even when she loses Farrendel, she takes it surprisingly well and focuses mostly on keeping a positive attitude for his sake, so he doesn’t feel her sadness through their “heart bond.” I never really felt her loss, her love for him, when she so easily could just decide not to feel bad “for his sake.” I want her to feel bad, I want her to miss him and to ache at his absence and to fear for what they’re doing to him. But no. That would just upset him more and hurt him more. So Essie doesn’t get to experience any negative feelings because it might upset her husband. Essie doesn’t get angry and determined to fight, she just keeps being her cheery little Stepford Wife self because being nice will keep everyone’s spirits up and make them hope and fight harder to preserve that hope!! :)
It just comes off as really flat and moralistic yet dishonest at the same time, because nobody would fucking react like this IRL. Essie might be a good person in-universe, but she drags the entire series down just by being perfect, cheery, and never, ever challenged or even allowed to challenge anything herself. Essie isn’t allowed to have any negative feelings because it might affect her husband, and yet we’re supposed to find this empowering somehow? We’re supposed to believe she’s spunky and confident and a sweet little firecracker of a redhead?
Eugh.
At least Melantha is an idiot, I guess. One whole female character gets to have a flaw, and she’s the almost-villain who needs to be fixed with love.
Idk man. The sexism in this series is like a constant undercurrent that grows stronger with each installment as our “understanding” of this world expands. All of Essie’s brothers, including the king, are at the front lines because they are manly men “have to” be there, while the women who aren’t Essie or Jalissa stay behind to be mothers and caretakers. It’s never expanded upon and just sort of accepted as part of both human and elven society and the narrative treats it like this obvious thing that even Essie doesn’t really bother noting how unfair and/or weird it is. There’s not even a single comment on it. Essie is in the war not because she can fight but because Farrendel needs her, and Jalissa is there because ... Um. Because ... she. Uh. She needs to be there when they confront Melantha? She’s Farrendel’s sister? Idk. Jalissa’s main point in this series so far seems to be the ship tease between her and Edmund that feels awkward and one-sided as fuck.
So yeah. The pacing and plot flowed along really well, but the characters and the writing and worldbuilding are all just really undercooked, which, at three books into the series, feels more glaring than ever.
But hey, at least it was a quick read!
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