Warp drive is a faster-than-light (FTL) spacecraft warm drive is a faster-than-light (FTL) spacecraft propulsion system in many science fiction works, most notably Star Trek. A spacecraft equipped with a warp drive may travel at speeds greater than that of light by many orders of magnitude. In contrast to other FTL technologies such as a jump drive or hyperdrive, the warp drive does not permit instantaneous travel between two points but involves a measurable passage of time which is pertinent to the concept. Spacecraft at warp velocity theoretically continue to interact with objects in "normal space". The general concept of "warp drive" was introduced by John W. Campbell in his 1931 novel Islands of Space.
Einstein's theory of special relativity states that energy and mass are interchangeable, thus, speed of light travel is impossible for material objects that weigh more than photons. The problem of a material object exceeding light speed is that an infinitely increasing amount of kinetic energy is required to attempt moving as fast as a massless photon. This problem can theoretically be solved by warping space to move an object instead of increasing the kinetic energy of the object to do so.
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| Warp Drive |
A warp drive would manipulate space-time itself to move a starship, taking advantage of a loophole in the laws of physics that prevent anything from moving faster than light. A concept for a real-life warp drive was suggested in 1994 by Mexican physicist Miguel Alcubierre; however, subsequent calculations found that such a device would require prohibitive amounts of energy.
Now physicists say that adjustments can be made to the proposed warp drive that would enable it to run on significantly less energy, potentially bringing the idea back from the realm of science fiction into science.
"There is hope," Harold "Sonny" White of NASA's Johnson Space Center said here Friday (Sept. 14) at the 100 Year Starship Symposium, a meeting to discuss the challenges of interstellar spaceflight.
Warping space-time
An Alcubierre warp drive would involve a football-shaped spacecraft attached to a large ring encircling it. This ring, potentially made of exotic matter, would cause space-time to warp around the starship, creating a region of contracted space in front of it and expanded space behind.
Meanwhile, the starship itself would stay inside a bubble of flat space-time that wasn't being warped at all.
"Everything within space is restricted by the speed of light," explained Richard Obousy, president of Icarus Interstellar, a non-profit group of scientists and engineers devoted to pursuing interstellar spaceflight. "But the really cool thing is space-time, the fabric of space is not limited by the speed of light.
" With this concept, the spacecraft would be able to achieve an effective speed of about 10 times the speed of light, all without breaking the cosmic speed limit.
The only problem is, previous studies estimated the warp drive would require a minimum amount of energy about equal to the mass-energy of the planet Jupiter.
But recently White calculated what would happen if the shape of the ring encircling the spacecraft was adjusted into more of a rounded donut, as opposed to a flat ring. He found in that case, the warp drive could be powered by a mass about the size of a spacecraft like the Voyager 1 probe NASA launched in 1977.
Furthermore, if the intensity of the space warps can oscillate over time, the energy required is reduced, even more, White found
. "The findings I presented today change it from impractical to plausible and worth further investigation," "The additional energy reduction realized by oscillating the bubble intensity is an interesting conjecture that we will enjoy looking at in the lab.
Laboratory Tests
White and his colleagues have begun experimenting with a mini version of the warp drive in their laboratory.
They set up what they call the White-Juday Warp Field Interferometer at the Johnson Space Center, essentially creating a laser interferometer that instigates micro versions of space-time warps.
"We're trying to see if we can generate a very tiny instance of this in a tabletop experiment, to try to perturb space-time by one part in 10 million," White said.
He called the project a "humble experiment" compared to what would be needed for a real warp drive but said it represents a promising first step.
And other scientists stressed that even outlandish-sounding ideas, such as the warp drive, need to be considered if humanity is serious about traveling to other stars.
"If we're ever going to become a true spacefaring civilization, we're going to have to think outside the box a little bit, we're going to have to be a little bit audacious," Obousy said.
Is the Warp Drive Possible
Rumor has it NASA is actually working on a real faster than light warp drive. So when do we get our first starship? Faster than light travel is a staple of science fiction. Star Trek warp drives zip around the galaxy at hundreds of times the speed of light. But traveling at the real cosmic speed limit of 1 times the speed of light would make for some pretty dull sci-fi.
It would have taken Han Solo 40 years to make the Kessel Run in 12 parsecs, traveling at only light speed. Understandably, both physicists and sci-fi fans dream of cracking FTL travel. Spanish physicist and sci-fi fan Miguel Alcubierre was so inspired by the idea that he decided that the Star Trek warp drive should become a reality.
In fact, he was inspired by Gene Roddenberry's choice of the word "warp." Alcubierre constructed a warp field in the mathematical language of Einstein's theory of general relativity, a real solution to the equations of GR that would actually allow faster than light travel. Yep, pretty much the ultimate in fan fiction.
But is it actually fiction?
NASA doesn't seem to think so. Its Eagleworks Laboratories is actually trying to produce and detect warp fields. More on that later. But if NASA's researching it, it must be legit, right? So when are we going to be warping around the galaxy? Let's break this idea apart.
First, it's important to note that this idea does not contradict the principle of a cosmic speed limit. That limit, the speed of light, refers to things-- mass, energy, information-- traveling through space.
However, according to general relativity, there's no limit on the relative speeds of two separate patches of spacetime. For example, as we talk about in this episode, the expansion of the universe means that very distant galaxies are moving apart from each other faster than light, even if the galaxies are relatively still in their local frames of reference. Also, below the event horizon of a black hole, spacetime cascades towards the central singularity faster than light, carrying light, matter, monkeys, and everything else with it.
Now, the spacetime around and within a black hole is predicted by solving Einstein's field equations around a point of extreme positive energy density. Basically, mass and energy tell us how space should warp. But if you're cheeky, you can actually just make up a solution to the equations of GR without starting with a real mass/energy distribution. That's what Alcubierre did.
He developed a spacetime description, a metric tensor, that describes a volume of nice, flat spacetime enclosed in a bubble of extreme curvature, a pinching or warping of spacetime in the surrounding shell that causes space to expand behind and contract in front of the bubble. As a result, the bubble is pushed and pulled by spacetime itself, moving at speeds only limited by the intensity of the warp.
A starship inside the bubble is carried along for the ride while feeling no acceleration at all. It's sort of like building a conveyor belt out of spacetime. You stand still concerning the conveyor belt, but the belt itself moves faster than light.
But is this even valid? Can you just make up a spacetime description and then essentially solve the Einstein equations backward to figure out what arrangement of matter and energy would be needed to create it?
It's sort of like giving the answer before you have the question. So, 42. Yeah, sure you can do this. There's just no guarantee that the resulting mass/energy distribution would be physically meaningful. In fact, when you try to do this for the warp field, you find that you need to produce a ring of negative energy density in a band around the ship to produce the right warp bubble. That means our ship looks something like this to produce a spacetime curvature like this. Unfortunately, it may not even be possible to make negative energy densities on large enough scales.
We can create something like it, a negative pressure, on quantum scales via the Casimir effect. But on macroscopic scales, you'd probably need some sort of exotic negative mass matter, like element zero, which is tricky, because there may be no such thing. There are other minor issues. Any FTL device can, in principle, be used to make a time machine. Excellent! Except for Stephen Hawking's chronology protection conjecture states that quantum mechanics will always stop causality-breaking actions.
It suggests that there's something in the deeper union of GR and quantum mechanics, the theory of everything, that prohibits the warp drive. One possible quantum disaster is that the extreme spacetime curvature of the warp bubble walls would roast the interior with crazy Hawking radiation. Does anyone else get the idea that Stephen Hawking really doesn't want us to build time machines? Suspicious. Here's another challenge.
Assuming that you can even make negative mass matter, to make a warp field, some of it would need to go outside the warp bubble, which means it gets left behind when you go to warp speed. There are some proposed solutions, one of which is to lay down the external negative energy conditions along the path before you leave, sort of like a warp highway. The first trip has to be made at sub-light speed. But I'm personally cool with the awesomeness of warp highways.
Last tricky thing-- as Alcubierre devised the warp bubble, he figured it would take a lot of negative energy. In fact, it would take significantly more negative energy than there is positive mass/energy in the entire observable universe. Later refinements brought this down to the mass equivalent of Jupiter. Either way, not practical. Happily, recent reworkings of the bubble geometry have cut this down further.
Thicken the walls of the warp field, and you get the negative mass/energy requirement down to the equivalent of maybe the moon or even an asteroid. Rapidly oscillate the warp field, and you hypothetically soften the fabric of space via higher dimensional effects-- literally, a hyperspace warp drive. And this brings mass needed down to kilograms. Given that we're just making up solutions to the Einstein equations, we could even shrink down the warp bubble while expanding the internal volume, Tardis style, which could get us down to needing only milligrams of negative mass. If the bubble is small enough, then we may not even need actual exotic matter. Quantum scale manipulation of the vacuum energy a la the Casimir effect may be enough. Check the description for the sources of all of these ideas.
Now, this sort of wild optimism has inspired NASA's Eagleworks Laboratory to try an experiment to create and detect a warp field. Now, this would be a field created by positive, not negative, energy density. But baby steps, right? It uses a Michelson interferometer, like a mini version of the one being used to detect gravitational waves, To measure the tiny changes in path length created by a warp field.
Now, some intriguing results have been detected. But interpretation is very, very challenging. So when are we going to be warping around the galaxy? If it's even possible, it'll take several centuries at a minimum. As I've argued before, we'll reach the stars by sub-light speed starships long before that. Even the Kugelblitz engine, the black hole drive, has fewer physics hurdles than the warp drive. Honestly, I think it's going to take an actively interstellar, or at least interplanetary, human race to motivate the monumental advancements needed to build the first warp drive.
The good news is we're going to need a ton of physicists to get to that point. Let's make it so on the next episode of "Space-Time." Last week, we talked about gravitational waves, and whether the advanced LIGO Observatory has maybe seen them. You guys had lots of amazing questions, so let's get to them. Renato Grigoli and others asked,
what about the LISA Mission?
LISA is amazing, although now it's ELISA, the Evolved Laser Interferometer Space Antenna. It'll be an orbiting gravitational wave observatory designed to detect much higher frequency gravitational waves than advanced LIGO. And this should actually allow it to detect binary star systems in our galaxy. The program is being developed by the European Space Agency.
NASA was originally a part of it but had to drop out due to funding cuts. And so now, the original plan is scaled back significantly. Now, that seems a shame, doesn't it?
The scheduled launch date is 2034. Santoshi asks if we have any comments on the BICEP 2 experiment. OK. So this was the much-hyped gravitational wave detection based on polarization anisotropies in the cosmic microwave background radiation that came out earlier this year. Yeah. So now, the money is on the signal actually being due to dust, not G waves. The lesson-- quadruple check your quadrupole. This is why LIGO won't say anything until at least the end of the year. Now, we want to know, if we find these G waves, will it change anything? Can we build something cool with them? Well, maybe. Quantum mechanics began as an abstract musing on the nature of reality.
And I doubt that Max Planck and Schrodinger and Bohr imagined that this crazy theory would lead to the invention of the transistor, a quantum mechanical device, let alone the computer, the smartphone, the Apple Watch. Tenebrae wants our thoughts on that amazing new Kepler Space Telescope result that the media is hyping that there's an alien megastructure eclipsing a distant star. Now, this is a stunning result. But as we say on "Space-Time," it's never aliens. Check out the actual signal that reveals this eclipsing material. Those dips are the drops in the star's brightness from some stuff moving in front of the star. It's dimmed by a crazy 20% at some points. Now, this is definitely not a clean geometric structure.
It looks like it has to be some fragmented clumpy material, like the proposed swarm of comets. That suggests a natural origin. Although I imagine it could possibly be the insanely vast ragtag colony of space structures surrounding a parent planet except it's never aliens. Radio telescopes are now pointed at it. So perhaps we'll know pretty soon. To Un Disclosed, I say, you laugh, but the first evidence of alien life may be the spectroscopic signature of biogenetic atmospheric methane on another world. To Simon Martin, don't worry. They're holding me very gently.
Trouble is to the nearest stars in this century as possible but only if we managed to achieve one of two things a proportion system that is able to burn for long periods of time at a minimum acceleration of 1g or some sort of warp drive just to put this into perspective if we had a ship like in the expence universe we could reach speeds in the millions of kilometers per hour think about this at a 1g of constant acceleration and burning for about nineteen point two hours we could reach Mars at its closest distance to earth or 55 million eight hundred thousand kilometers in just thirty 2.5 hours compared to the current time which is in between six to eight months that's a huge gain just to show you how much this really matters the same acceleration would grant us a trip to Pluto in just seventy three point seven days it took the new Horizons probe nine point five years to get there so Rockets will help us a lot with the exploration of our own solar system and it is a topic that I will be exploring in later videos but what about other stars like Proxima Centauri which is 4.2 light years away well to reach Proxima Centauri at 40 point 14 trillion kilometers away
it would take about six hundred eighty three thousand four hundred sixty five days or 1,873 years to be exact but then again taking to account all other problems related to traveling this far let's face it it's just not viable the Alcubierre warp field would help us surpass the speed of light many times which means that if we had a ship that could go 10 times the speed of light it would take only 153 days to get to Proxima Centauri much more reasonable of it but building a warp drive is not an easy task hello everyone subject zero here Miguel Alcubierre is a theoretical physicist famous for the warp field theory in May 1994 he published a paper titled the warp drive hyper fast travel within general relativity however his goal of this paper contrary to popular belief had little to do with warp drives it was to show that a distortion of space-time is indeed possible within the realms of general relativity and therefore we could travel faster than the speed of light his objective was simple he wanted to verify
if there was a way to deform space in such a manner that its contraction and expansion would provide movement to a body inside the space-time warp bubble the idea was to form a bubble around the ship and at the same time the inside of the bubble would remain untouched or flat as they say we all know that huge masses can warp space so the idea came from two factors the ability for space to contract like what happens with large concentrations of matter and expand which is what is happening with the universe the only problem with his idea is that the transition from contraction to expansion requires a massive amount of energy mainly focus on what they call exotic matter with negative mass as complex as it may appear to be in this case since normal matter warp space inwards is why we have gravity negative mass would warp space outwards this is the key of his warp field theory to better visualize this think of it as the path of the ship inside a tube in order for the warp field to work it would contract the front of the tube towards the ship bringing some distant point of space-time closer to it and as it approaches the center it slowly transitions to an expansion behind it so space-time moves around the ship and inside the bubble nothing is moving or space-time remains flat since there is no known limit to how space-time can contract or expand in theory anything inside the bubble can travel faster than the speed of light all you need to do is increase the warp field about ten years later
NASA picked up on this project and dr. Harold white from Eagle Works stepped in to verify if the amount of energy necessary for the work field to work could be brought down to something more realistic his great insight was to oscillate in between states or from contraction to expansion by using a thoris around the ship he derived his calculation from the Alcubierre metric and described three main functions the warp bubble shaping function york time which is the measure of expansion and contraction of space and energy density this is when we get this chart what he proposed was that to decrease the mass necessary to make this work and have your ship traveling at 10 times the speed of light you could in turn increase the oscillation of the torus using the york time function but that comes at a cost with a mass equivalence of Jupiter you would have the optimal work bubble conformation that would enable a ship to be located inside the bubble without any distortion or any harm to the ship as you increase the oscillation you diminish the total exotic mass requirements up to a point where all you need is about 700 kilograms of exotic matter but the bubble would be so thick pretty much destroying anything inside the bubble that is when the second torus is introduced with two oscillating Tauri the thickness of the warp bubble can be controlled allowing for flat space to exist inside the bubble keeping everything intact even if we managed to make that ship we still have to deal with other external factors like for instance all the trap energy in front of the bubble anything that is on the way of the ship route would get stuck in front of the bubble so when you stop the ship the energy would be released forward with high intensity so one thing to avoid at all time would be to point your ship at the planet or whenever you arrive you'll pretty much destroy the planet then again this is getting more and more complex by the minute and in the same fashion as a queer all dr. white attempted to do here was to bring the war field theory to of the realm of maybe plausible and that is exactly what he achieved one thing almost all scientists discussing this topic agree is that warping space is possible or at least the numbers tells us that is possible nevertheless what is most likely to happen is work field achieving subliminal speeds like 10% of the speed of light that is by far the most plausible scenario for the next 80 years and 10% of the speed of light is a big deal after all to achieve the same speed using rocket technology you would have to burn at 1g of constant acceleration for 35 days think about that what could change everything though is antimatter there is something about antimatter that we don't know and most likely it will take years for us to acquire a definitive answer for it that is how does it react with gravity is it repelled or is it attracted by it like anything else or better yet what kind of gravitational field would large quantities produce the thing is we really don't know but tests at the CERN facility with G bar experiments will give us some clues this decade how antimatter behaves with gravity is still a mystery and so far no experimental direct measure has ever been successfully performed the goal of G bar is to test the Einstein weak equivalence principle which states that the trajectory of a test particle is independent of its composition and internal structure when it is only submitted to gravitational forces this fundamental principle has never been directly tested with antimatter G bar will directly measure the freefall acceleration note a G of neutral anti hydrogen atoms in the terrestrial gravitational field then again it will take years for us to gather enough quantities anyway whatever they will be able to produce this year although helpful will most likely be inconclusive in many aspects but remember what we are looking for is a concentration of mass that will allow us to expend space but if the experiment is successful and antimatter turns out to be repelled by gravity aside from revolutionising everything it could in theory be used as the exotic matter that al Kabeer described or at least open the door to a completely new field of physics alright folks that's it we're done here. propulsion system in many science fictions works, most notably Star Trek. A spacecraft equipped with a warp drive may travel at speeds greater than that of light by many orders of magnitude. In contrast to other FTL technologies such as a jump drive or hyperdrive, the warp drive does not permit instantaneous travel between two points but involves a measurable passage of time which is pertinent to the concept. Spacecraft at warp velocity theoretically continue to interact with objects in "normal space". The general concept of "warp drive" was introduced by John W. Campbell in his 1931 novel Islands of Space. Einstein's theory of special relativity states that energy and mass are interchangeable, thus, speed of light travel is impossible for material objects that weigh more than photons. The problem of a material object exceeding light speed is that an infinitely increasing amount of kinetic energy is required to attempt moving as fast as a massless photon. This problem can theoretically be solved by warping space to move an object instead of increasing the kinetic energy of the object to do so. A warp drive would manipulate space-time itself to move a starship, taking advantage of a loophole in the laws of physics that prevent anything from moving faster than light. A concept for a real-life warp drive was suggested in 1994 by Mexican physicist Miguel Alcubierre; however, subsequent calculations found that such a device would require prohibitive amounts of energy. Now physicists say that adjustments can be made to the proposed warp drive that would enable it to run on significantly less energy, potentially bringing the idea back from the realm of science fiction into science. "There is hope," Harold "Sonny" White of NASA's Johnson Space Center said here Friday (Sept. 14) at the 100 Year Starship Symposium, a meeting to discuss the challenges of interstellar spaceflight. Click here for more Space.com videos... CLOSE Star Trek's Warp Drive: Are We There Yet? | Video Volume 0% PLAY SOUND Warping space-time An Alcubierre warp drive would involve a football-shaped spacecraft attached to a large ring encircling it. This ring, potentially made of exotic matter, would cause space-time to warp around the starship, creating a region of contracted space in front of it and expanded space behind. [Star Trek's Warp Drive: Are We There Yet? | Video] Meanwhile, the starship itself would stay inside a bubble of flat space-time that wasn't being warped at all. "Everything within space is restricted by the speed of light," explained Richard Obousy, president of Icarus Interstellar, a non-profit group of scientists and engineers devoted to pursuing interstellar spaceflight. "But the really cool thing is space-time, the fabric of space, is not limited by the speed of light." With this concept, the spacecraft would be able to achieve an effective speed of about 10 times the speed of light, all without breaking the cosmic speed limit. The only problem is, previous studies estimated the warp drive would require a minimum amount of energy about equal to the mass-energy of the planet Jupiter. But recently White calculated what would happen if the shape of the ring encircling the spacecraft was adjusted into more of a rounded donut, as opposed to a flat ring. He found in that case, the warp drive could be powered by a mass about the size of a spacecraft like the Voyager 1 probe NASA launched in 1977. Furthermore, if the intensity of the space warps can oscillate over time, the energy required is reduced, even more, White found. "The findings I presented today change it from impractical to plausible and worth further investigation," White told SPACE.com.
"The additional energy reduction realized by oscillating the bubble intensity is an interesting conjecture that we will enjoy looking at in the lab." L White and his colleagues have begun experimenting with a mini version of the warp drive in their laboratory. They set up what they call the White-Juday Warp Field Interferometer at the Johnson Space Center, essentially creating a laser interferometer that instigates micro versions of space-time warps. "We're trying to see if we can generate a very tiny instance of this in a tabletop experiment, to try to perturb space-time by one part in 10 million," White said. He called the project a "humble experiment" compared to what would be needed for a real warp drive but said it represents a promising first step. And other scientists stressed that even outlandish-sounding ideas, such as the warp drive, need to be considered if humanity is serious about traveling to other stars. "If we're ever going to become a true spacefaring civilization, we're going to have to think outside the box a little bit, we're going to have to be a little bit audacious," Obousy said. Rumor has it NASA is actually working on a real faster than light warp drive. So when do we get our first starship? Faster than light travel is a staple of science fiction. Star Trek warp drives zip around the galaxy at hundreds of times the speed of light. But traveling at the real cosmic speed limit of 1 times the speed of light would make for some pretty dull sci-fi. It would have taken Han Solo 40 years to make the Kessel Run in 12 parsecs, traveling at only light speed. Understandably, both physicists and sci-fi fans dream of cracking FTL travel. Spanish physicist and sci-fi fan Miguel Alcubierre was so inspired by the idea that he decided that the Star Trek warp drive should become a reality. In fact, he was inspired by Gene Roddenberry's choice of the word "warp."
Alcubierre constructed a warp field in the mathematical language of Einstein's theory of general relativity, a real solution to the equations of GR that would actually allow faster than light travel. Yep, pretty much the ultimate in fan fiction. But is it actually fiction?
NASA doesn't seem to think so. Its Eagleworks Laboratories is actually trying to produce and detect warp fields. More on that later. But if NASA's researching it, it must be legit, right? So when are we going to be warping around the galaxy? Let's break this idea apart.
First, it's important to note that this idea does not contradict the principle of a cosmic speed limit. That limit, the speed of light, refers to things-- mass, energy, information-- traveling through space. However, according to general relativity, there's no limit on the relative speeds of two separate patches of spacetime. For example, as we talk about in this episode, the expansion of the universe means that very distant galaxies are moving apart from each other faster than light, even if the galaxies are relatively still in their local frames of reference.
Also, below the event horizon of a black hole, spacetime cascades towards the central singularity faster than light, carrying light, matter, monkeys, and everything else with it. Now, the spacetime around and within a black hole is predicted by solving Einstein's field equations around a point of extreme positive energy density.
Basically, mass and energy tell us how space should warp. But if you're cheeky, you can actually just make up a solution to the equations of GR without starting with a real mass/energy distribution. That's what Alcubierre did. He developed a spacetime description, a metric tensor, that describes a volume of nice, flat spacetime enclosed in a bubble of extreme curvature, a pinching or warping of spacetime in the surrounding shell that causes space to expand behind and contract in front of the bubble.
As a result, the bubble is pushed and pulled by spacetime itself, moving at speeds only limited by the intensity of the warp. A starship inside the bubble is carried along for the ride while feeling no acceleration at all. It's sort of like building a conveyor belt out of spacetime.
You stand still concerning the conveyor belt, but the belt itself moves faster than light. But is this even valid? Can you just make up a spacetime description and then essentially solve the Einstein equations backward to figure out what arrangement of matter and energy would be needed to create it? It's sort of like giving the answer before you have the question. So, 42. Yeah, sure you can do this.
There's just no guarantee that the resulting mass/energy distribution would be physically meaningful. In fact, when you try to do this for the warp field, you find that you need to produce a ring of negative energy density in a band around the ship to produce the right warp bubble. That means our ship looks something like this to produce a spacetime curvature like this. Unfortunately, it may not even be possible to make negative energy densities on large enough scales. We can create something like it, a negative pressure, on quantum scales via the Casimir effect. But on macroscopic scales, you'd probably need some sort of exotic negative mass matter, like element zero, which is tricky, because there may be no such thing.
There are other minor issues. Any FTL device can, in principle, be used to make a time machine. Excellent! Except for Stephen Hawking's chronology protection conjecture states that quantum mechanics will always stop causality-breaking actions. It suggests that there's something in the deeper union of GR and quantum mechanics, the theory of everything, that prohibits the warp drive. One possible quantum disaster is that the extreme spacetime curvature of the warp bubble walls would roast the interior with crazy Hawking radiation. Does anyone else get the idea that Stephen Hawking really doesn't want us to build time machines? Suspicious.
Here's another challenge. Assuming that you can even make negative mass matter, to make a warp field, some of it would need to go outside the warp bubble, which means it gets left behind when you go to warp speed. There are some proposed solutions, one of which is to lay down the external negative energy conditions along the path before you leave, sort of like a warp highway. The first trip has to be made at sub-light speed. But I'm personally cool with the awesomeness of warp highways. Last tricky thing-- as Alcubierre devised the warp bubble, he figured it would take a lot of negative energy. In fact, it would take significantly more negative energy than there is positive mass/energy in the entire observable universe. Later refinements brought this down to the mass equivalent of Jupiter. Either way, not practical. Happily, recent reworkings of the bubble geometry have cut this down further.
Thicken the walls of the warp field, and you get the negative mass/energy requirement down to the equivalent of maybe the moon or even an asteroid. Rapidly oscillate the warp field, and you hypothetically soften the fabric of space via higher dimensional effects-- literally, a hyperspace warp drive. And this brings mass needed down to kilograms. Given that we're just making up solutions to the Einstein equations, we could even shrink down the warp bubble while expanding the internal volume, Tardis style, which could get us down to needing only milligrams of negative mass. If the bubble is small enough, then we may not even need actual exotic matter. Quantum scale manipulation of the vacuum energy a la the Casimir effect may be enough. Check the description for the sources of all of these ideas. Now, this sort of wild optimism has inspired NASA's Eagleworks Laboratory to try an experiment to create and detect a warp field. Now, this would be a field created by positive, not negative, energy density. But baby steps, right? It uses a Michelson interferometer, like a mini version of the one being used to detect gravitational waves,
To measure the tiny changes in path length created by a warp field. Now, some intriguing results have been detected. But interpretation is very, very challenging. So when are we going to be warping around the galaxy? If it's even possible, it'll take several centuries at a minimum. As I've argued before, we'll reach the stars by sub-light speed starships long before that. Even the Kugelblitz engine, the black hole drive, has fewer physics hurdles than the warp drive. Honestly, I think it's going to take an actively interstellar, or at least interplanetary, human race to motivate the monumental advancements needed to build the first warp drive. The good news is we're going to need a ton of physicists to get to that point. Let's make it so on the next episode of "Space-Time." Last week, we talked about gravitational waves, and whether the advanced LIGO Observatory has maybe seen them. You guys had lots of amazing questions, so let's get to them. Renato Grigoli and others asked,
what about the LISA Mission?
LISA is amazing, although now it's ELISA, the Evolved Laser Interferometer Space Antenna. It'll be an orbiting gravitational wave observatory designed to detect much higher frequency gravitational waves than advanced LIGO. And this should actually allow it to detect binary star systems in our galaxy. The program is being developed by the European Space Agency. NASA was originally a part of it but had to drop out due to funding cuts. And so now, the original plan is scaled back significantly. Now, that seems a shame, doesn't it? The scheduled launch date is 2034.
Santoshi asks if we have any comments on the BICEP 2 experiment. OK. So this was the much-hyped gravitational wave detection based on polarization anisotropies in the cosmic microwave background radiation that came out earlier this year. Yeah. So now, the money is on the signal actually being due to dust, not G waves. The lesson-- quadruple check your quadrupole. This is why LIGO won't say anything until at least the end of the year. Now, MrSh1pman wants to know, if we find these G waves, will it change anything? Can we build something cool with them? Well, maybe.
Quantum mechanics began as an abstract musing on the nature of reality. And I doubt that Max Planck and Schrodinger and Bohr imagined that this crazy theory would lead to the invention of the transistor, a quantum mechanical device, let alone the computer, the smartphone, the Apple Watch. Tenebrae wants our thoughts on that amazing new Kepler Space Telescope result that the media is hyping that there's an alien megastructure eclipsing a distant star. Now, this is a stunning result. But as we say on "Space-Time," it's never aliens. Check out the actual signal that reveals this eclipsing material. Those dips are the drops in the star's brightness from some stuff moving in front of the star. It's dimmed by a crazy 20% at some points. Now, this is definitely not a clean geometric structure. It looks like it has to be some fragmented clumpy material, like the proposed swarm of comets. That suggests a natural origin. Although I imagine it could possibly be the insanely vast ragtag colony of space structures surrounding a parent planet== except its never aliens. Radio telescopes are now pointed at it. So perhaps we'll know pretty soon. To Un Disclosed, I say, you laugh, but the first evidence of alien life may be the spectroscopic signature of biogenetic atmospheric methane on another world.
To Simon Martin, don't worry. They're holding me very gently. trouble is to the nearest stars in this century as possible but only if we managed to achieve one of two things a proportion system that is able to burn for long periods of time at a minimum acceleration of 1g or some sort of warp drive just to put this into perspective if we had a ship like in the expence universe we could reach speeds in the millions of kilometers per hour think about this at a 1g of constant acceleration and burning for about nineteen point two hours we could reach Mars at its closest distance to earth or 55 million eight hundred thousand kilometers in just thirty 2.5 hours compared to the current time which is in between six to eight months that's a huge gain just to show you how much this really matters the same acceleration would grant us a trip to Pluto in just seventy three point seven days it took the new Horizons probe nine point five years to get there so Rockets will help us a lot with the exploration of our own solar system and it is a topic that I will be exploring in later videos but what about other stars like Proxima Centauri which is 4.2 light years away well to reach Proxima Centauri at 40 point 14 trillion kilometers away it would take about six hundred eighty three thousand four hundred sixty five days or 1,873 years to be exact but then again taking to account all other problems related to traveling this far let's face it it's just not viable the Alcubierre warp field would help us surpass the speed of light many times which means that if we had a ship that could go 10 times the speed of light
it would take only 153 days to get to Proxima Centauri much more reasonable of it but building a warp drive is not an easy task hello everyone subject zero here Miguel Alcubierre is a theoretical physicist famous for the warp field theory in May 1994 he published a paper titled the warp drive hyper fast travel within general relativity however his goal of this paper contrary to popular belief had little to do with warp drives it was to show that a distortion of space-time is indeed possible within the realms of general relativity and therefore we could travel faster than the speed of light his objective was simple he wanted to verify if there was a way to deform space in such a manner that its contraction and expansion would provide movement to a body inside the space-time warp bubble the idea was to form a bubble around the ship and at the same time the inside of the bubble would remain untouched or flat as they say we all know that huge masses can warp space so the idea came from two factors the ability for space to contract like what happens with large concentrations of matter and expand which is what is happening with the universe the only problem with his idea is that the transition from contraction to expansion requires a massive amount of energy mainly focus on what they call exotic matter with negative mass as complex as it may appear to be in this case since normal matter warp space inwards is why we have gravity negative mass would warp space outwards this is the key of his warp field theory to better visualize this think of it as the path of the ship inside a tube in order for the warp field to work it would contract the front of the tube towards the ship bringing some distant point of space-time closer to it and as it approaches the center it slowly transitions to an expansion behind it so space-time moves around the ship and inside the bubble nothing is moving or space-time remains flat since there is no known limit to how space-time can contract or expand in theory anything inside the bubble can travel faster than the speed of light all you need to do is increase the warp field about ten years later NASA picked up on this project and dr. Harold white from Eagle Works stepped in to verify if the amount of energy necessary for the work field to work could be brought down to something more realistic his great insight was to oscillate in between states or from contraction to expansion by using a thoris around the ship he derived his calculation from the Alcubierre metric and described three main functions the warp bubble shaping function york time which is the measure of expansion and contraction of space and energy density this is when we get this chart what he proposed was that to decrease the mass necessary to make this work and have your ship traveling at 10 times the speed of light you could in turn increase the oscillation of the torus using the york time function but that comes at a cost with a mass equivalence of Jupiter you would have the optimal work bubble conformation that would enable a ship to be located inside the bubble without any distortion or any harm to the ship as you increase the oscillation you diminish the total exotic mass requirements up to a point where all you need is about 700 kilograms of exotic matter but the bubble would be so thick pretty much destroying anything inside the bubble that is when the second torus is introduced with two oscillating Tauri the thickness of the warp bubble can be controlled allowing for flat space to exist inside the bubble keeping everything intact even if we managed to make that ship we still have to deal with other external factors like for instance all the trap energy in front of the bubble anything that is on the way of the ship route would get stuck in front of the bubble so when you stop the ship the energy would be released forward with high intensity so one thing to avoid at all time would be to point your ship at the planet or whenever you arrive you'll pretty much destroy the planet then again this is getting more and more complex by the minute and in the same fashion as a queer all dr. white attempted to do here was to bring the war field theory to of the realm of maybe plausible and that is exactly what he achieved one thing almost all scientists discussing this topic agree is that warping space is possible or at least the numbers tells us that is possible nevertheless what is most likely to happen is work field achieving subliminal speeds like 10% of the speed of light that is by far the most plausible scenario for the next 80 years and 10% of the speed of light is a big deal after all to achieve the same speed using rocket technology you would have to burn at 1g of constant acceleration for 35 days think about that what could change everything though is antimatter there is something about antimatter that we don't know and most likely it will take years for us to acquire a definitive answer for it that is how does it react with gravity is it repelled or is it attracted by it like anything else or better yet what kind of gravitational field would large quantities produce the thing is we really don't know but tests at the CERN facility with G bar experiments will give us some clues this decade how antimatter behaves with gravity is still a mystery and so far no experimental direct measure has ever been successfully performed the goal of G bar is to test the Einstein weak equivalence principle which states that the trajectory of a test particle is independent of its composition and internal structure when it is only submitted to gravitational forces this fundamental principle has never been directly tested with antimatter G bar will directly measure the freefall acceleration note a G of neutral anti hydrogen atoms in the terrestrial gravitational field then again it will take years for us to gather enough quantities anyway whatever they will be able to produce this year although helpful will most likely be inconclusive in many aspects but remember what we are looking for is a concentration of mass that will allow us to expend space but if the experiment is successful and antimatter turns out to be repelled by gravity aside from revolutionising everything it could in theory be used as the exotic matter that al Kabeer described or at least open the door to a completely new field of physics alright folks that's it we're done here.
