When Was Dark Matter Formed?

Was dark matter created during the Big Bang?
This full-sky map from the Planck mission shows matter between Earth and the edge of the observable universe. Regions with more mass show up as lighter areas while regions with less mass are darker. The grayed-out areas are where light from our own galaxy was too bright, blocking Planck's ability to map the more distant matter. Image credit: ESA/NASA/JPL-Caltech

This full-sky map from the Planck mission shows matter between Earth and the edge of the observable universe. Regions with more mass show up as lighter areas while regions with less mass are darker. The grayed-out areas are where light from our own galaxy was too bright, blocking Planck's ability to map the more distant matter. Image credit: ESA/NASA/JPL-Caltech

Originally posted on Forbes!

Our current understanding of the event dubbed the Big Bang implies that all matter, and all energy, appeared in our Universe at that moment. Ever since then, the Universe has been changing, and those changes are reflected in the behavior of matter and energy.

Unfortunately, we can’t observe this event directly in order to get a better understanding of how the earliest stages of the Universe’s evolution unfolded. This isn’t something that can be fixed with a more powerful telescope, either; at an early point in time, the Universe was quite simply opaque to light. And much in the same way that I can’t see through furniture, even the best observatories can’t penetrate into the depths of time beyond this point.

To explain how we know that dark matter has been around since the very early Universe, I have to talk a bit about how we’ve managed to learn about the early Universe in general.

This map shows the oldest light in our universe, as detected with the greatest precision yet by the Planck mission. The ancient light, called the cosmic microwave background, was imprinted on the sky when the universe was 370,000 years old. Image credit: ESA and the Planck Collaboration

This map shows the oldest light in our universe, as detected with the greatest precision yet by the Planck mission. The ancient light, called the cosmic microwave background, was imprinted on the sky when the universe was 370,000 years old. Image credit: ESA and the Planck Collaboration

You may have seen this image before. The cosmic microwave background, which has the alternate name of the “oldest light in the Universe” is the surface of the cloudy Universe, just as it became transparent to light. There’s a lot of information about the early Universe embedded in this image, which tells us about the temperature of the Universe, and how the matter which later became clusters of galaxies was distributed around.

It’s this latter point which points to the existence of dark matter in the very early Universe.

One of the ways this image is analysed is by looking at the characteristic spacing between bright and cool patches. If this were 100% randomly distributed, you wouldn’t expect to find things at any particular distance more frequently than any other distance. And that could have been the way our Universe was arranged, but it isn’t. Our Universe has a few preferred spacings.

One of these sets of spacings is formally termed Baryon Acoustic Oscillations. Baryons are simply any matter, the protons and neutrons and electrons that make up humans and stars and dogs. Acoustic oscillations should sound like a musical term more than a physics one, and it’s not without reason. The early Universe was much like a fluid in many ways, and information travelled through it like sound through water. The Baryon Acoustic Oscillations, therefore, refers to the way that the stuff of atoms rippled through the early Universe.

Astronomers using NASA's Hubble Space Telescope took advantage of a giant cosmic magnifying glass to create a detailed map of dark matter in the universe. Image credit: NASA, ESA, and D. Coe (NASA JPL/Caltech and STScI)

Astronomers using NASA's Hubble Space Telescope took advantage of a giant cosmic magnifying glass to create a detailed map of dark matter in the universe. Image credit: NASA, ESA, and D. Coe (NASA JPL/Caltech and STScI)

The cause of those ripples? A pressure from dark matter. When the Universe became less fluid, the protons, electrons and neutrons were frozen into place, wherever their ripple had left them. There’s a huge number of these ripples in the Universe, so rather than a single stone thrown into a lake, our image is more like a water surface pummeled by a tropical rainstorm. The spacing between where the dark matter sat, and where some of the baryons in our Universe had rippled outwards to, is reflected in the statistics of the cosmic microwave image. Without the presence of dark matter, we wouldn’t expect to see this exact spacing. And if dark matter was present so early in the Universe, it probably was formed in the big bang. At the very least, it couldn’t have been formed later, the way the heavy elements in our Universe were formed by stars, many years after this snapshot of our early Universe.

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How Dense Is Dark Matter?

Components of the galaxy cluster Abell 2744, also known as the Pandora Cluster: galaxies (white), hot gas (red) and dark matter (blue). The image measures about half a degree across. The image is sprinkled with foreground stars belonging to our Galaxy, the Milky Way, which are visible as the roundish objects with diffraction spikes. Image credit: ESA/XMM-Newton (X-rays); ESO/WFI (optical); NASA/ESA & CFHT (dark matter)

Components of the galaxy cluster Abell 2744, also known as the Pandora Cluster: galaxies (white), hot gas (red) and dark matter (blue). The image measures about half a degree across. The image is sprinkled with foreground stars belonging to our Galaxy, the Milky Way, which are visible as the roundish objects with diffraction spikes. Image credit: ESA/XMM-Newton (X-rays); ESO/WFI (optical); NASA/ESA & CFHT (dark matter)

Originally posted on Forbes!

It very much depends on where you are! Dark matter as we understand it must be some kind of particle, or at least act like some kind of particle. We’re not exactly clear on what the exact nature of that particle would be, or what its individual mass is, or what kind of interactions it ought to have either with itself or with the matter that makes up our planet and all the stars.

But it certainly does seem that dark matter isn’t spread evenly throughout the entire universe. It’s clustered in lumps, and those lumps become the homes to galaxies. Small gatherings of dark matter are generally assumed to be roundish, since that’s the easiest shape for a three dimensional object to form under the influence of gravity.

For galaxy clusters, we can actually map out the shape of the dark matter surrounding these thousands of galaxies by looking at the way that light bends around that part of the Universe. Not all clusters have particularly spherical dark matter surroundings, and we can see the irregularities because the light from galaxies behind the cluster is not bent in the same way along all of the cluster’s edges.

At first glance, this cosmic kaleidoscope of purple, blue and pink offers a strikingly beautiful — and serene — snapshot of the cosmos. However, this multi-coloured haze actually marks the site of two colliding galaxy clusters, forming a single object known as MACS J0416.1-2403 (or MACS J0416 for short). Image credit: NASA, ESA, CXC, NRAO/AUI/NSF, STScI, and G. Ogrean (Stanford University)

At first glance, this cosmic kaleidoscope of purple, blue and pink offers a strikingly beautiful — and serene — snapshot of the cosmos. However, this multi-coloured haze actually marks the site of two colliding galaxy clusters, forming a single object known as MACS J0416.1-2403 (or MACS J0416 for short). Image credit: NASA, ESA, CXC, NRAO/AUI/NSF, STScI, and G. Ogrean (Stanford University)

Within any of these collections of dark matter (technically called halos) surrounding a galaxy or a collection of galaxies, the dark matter is densest at the center, and becomes gradually more diffuse the further out you go. For our own Milky Way, that means that the dark matter density is the highest towards the very center of the galaxy, and out near our solar system, the dark matter density is significantly lower.

Most galaxies contain significantly more mass in dark matter than in luminous matter, but this isn’t because it’s more dense -- the dark matter halo is simply much larger. In the case of the dark matter surrounding our Milky Way, it’s also spherical and not effectively flat, like the bright part of the galaxy is. You can pack a lot more material in a sphere than you can in a circle, so the combination of the dark matter halo being physically larger and a sphere means you wind up with a lot more mass.

This is a mass map of galaxy cluster Cl0024+1654 derived from an extensive Hubble Space Telescope campaign. The colour image is made from two images: a dark-matter map (the blue part of the image) and a 'luminous-matter' map determined from the galaxies in the cluster (the red part of the image). Image credit: European Space Agency, NASA and Jean-Paul Kneib (Observatoire Midi-Pyrénées, France/Caltech, USA)

This is a mass map of galaxy cluster Cl0024+1654 derived from an extensive Hubble Space Telescope campaign. The colour image is made from two images: a dark-matter map (the blue part of the image) and a 'luminous-matter' map determined from the galaxies in the cluster (the red part of the image). Image credit: European Space Agency, NASA and Jean-Paul Kneib (Observatoire Midi-Pyrénées, France/Caltech, USA)

The dark matter density near the solar system, from what I could find, sits at around 0.006 solar masses per cubic parsec, which is a set of units that’s not going to make much sense unless you’re a professional astrophysicist. This is extremely low density. Six-thousandths of a solar mass is approximately the same as six Jupiter mass planets, and a parsec is a 75% of the distance from the Sun to the nearest star. So this means if you wanted to reproduce the dark matter density with the luminous matter that planets are made of, you’d have to clear out a cube of space that’s three light years to a side of absolutely everything. No dust, no gas, no stars, no planets. You get six Jupiters in that box, and you’ll have to spread those Jupiters around, since we don’t have any indication that dark matter comes in chunks.

We can scale this metaphor down a bit; if you wanted to get the same kind of density but in a cubic kilometer, you’d have to evacuate that square kilometer of absolutely every single atom of material. A single grain of birch pollen floating in that cubic kilometer would contain 20 times more mass than there would be in dark matter in that same volume.

At the center of the galaxy, the dark matter should be more than 150 times more concentrated, but this is very difficult to measure within our own galaxy. So far, our observations seem to line up with the models we’ve developed, but there’s definitely room to improve. In any case, 150 times the density of the solar neighborhood is still not very dense! That gets us all of about eight grains of pollen.

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Could Dark Matter Ever Form A Star?

Does dark matter have mass? Could dark matter ever form a star?
This artist’s impression shows the Milky Way galaxy. The blue halo of material surrounding the galaxy indicates the expected distribution of the mysterious dark matter, which was first introduced by astronomers to explain the rotation properties of the galaxy and is now also an essential ingredient in current theories of the formation and evolution of galaxies. New measurements show that the amount of dark matter in a large region around the Sun is far smaller than predicted and have indicated that there is no significant dark matter at all in our neighbourhood. Image credit: ESO/L. Calçada

This artist’s impression shows the Milky Way galaxy. The blue halo of material surrounding the galaxy indicates the expected distribution of the mysterious dark matter, which was first introduced by astronomers to explain the rotation properties of the galaxy and is now also an essential ingredient in current theories of the formation and evolution of galaxies. New measurements show that the amount of dark matter in a large region around the Sun is far smaller than predicted and have indicated that there is no significant dark matter at all in our neighbourhood. Image credit: ESO/L. Calçada

Originally posted at Forbes!

Having mass is the one thing that’s really certain about dark matter. Dark matter's existence was discovered by measurements that meant that there had to be some extra, invisible, material, which was contributing mass to the galaxies we were looking at. What kind of material it is exactly remains a bit mysterious, but we’re pretty sure it should be some kind of fundamental particle, and many ongoing experiments are being run to try and narrow down what that particle could look like. It seems that dark matter only interacts with the rest of our Universe’s atoms (like the hydrogen of a gas cloud, or the iron in your blood) through gravity.

This dwarf spheroidal galaxy in the constellation Fornax is a satellite of our Milky Way and is one of 10 used in Fermi's dark matter search. The motions of the galaxy's stars indicate that it is embedded in a massive halo of matter that cannot be seen. Credits: ESO/Digital Sky Survey 2

This dwarf spheroidal galaxy in the constellation Fornax is a satellite of our Milky Way and is one of 10 used in Fermi's dark matter search. The motions of the galaxy's stars indicate that it is embedded in a massive halo of matter that cannot be seen. Credits: ESO/Digital Sky Survey 2

We also know that dark matter does cluster together, because the gathering of dark matter into massive, unseen spheres within our cosmos are the birthplaces of galaxies. Every galaxy we’ve looked at with sufficient precision has told us that there is more dark matter than there is luminous matter. In order to directly measure dark matter, the easiest methods involve measuring the rotation of the galaxy, which we can only do for nearby galaxies, or by measuring a gravitational lens, which we can only do for very massive, geometrically lucky galaxies. But where these measurements are possible, dark matter surrounding our Universe’s galaxies seems to be omnipresent. It’s to the point where the presence of dark matter is one way of defining what a galaxy is -- if the collection of stars is too small to have its own surrounding nest of dark matter, it can’t be a formal galaxy. As we get a little more cunning about how to look for faint galaxies, we are starting to find darker and darker galaxies, which are comprised of more and more dark matter and less and less luminous matter.

But to make a dark star and not just a dark galaxy is a bit harder, because stars have to collapse down in a very small region of space. If your star is made of normal matter, part of this collapsing process occurs because the gas particles cool down, which allows them to take up less space. But dark matter particles don’t seem to interact with each other or with normal matter except through the force of gravity -- these dark matter particles can’t shed heat and become more densely concentrated.

Two stars shine through the center of a ring of cascading dust in this image taken by the NASA/ESA Hubble Space Telescope. The star system is named DI Cha, and while only two stars are apparent, it is actually a quadruple system containing two sets of binary stars. As this is a relatively young star system it is surrounded by dust. The young stars are molding the dust into a wispy wrap. The host of this alluring interaction between dust and star is the Chamaeleon I dark cloud — one of three such clouds that comprise a large star-forming region known as the Chamaeleon Complex. DI Cha's juvenility is not remarkable within this region. In fact, the entire system is among not only the youngest but also the closest collections of newly formed stars to be found and so provides an ideal target for studies of star formation. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt

Two stars shine through the center of a ring of cascading dust in this image taken by the NASA/ESA Hubble Space Telescope. The star system is named DI Cha, and while only two stars are apparent, it is actually a quadruple system containing two sets of binary stars. As this is a relatively young star system it is surrounded by dust. The young stars are molding the dust into a wispy wrap. The host of this alluring interaction between dust and star is the Chamaeleon I dark cloud — one of three such clouds that comprise a large star-forming region known as the Chamaeleon Complex. DI Cha's juvenility is not remarkable within this region. In fact, the entire system is among not only the youngest but also the closest collections of newly formed stars to be found and so provides an ideal target for studies of star formation. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt

From a purely theoretical perspective, it is possible to have a star with a significant fraction of dark matter inside it. However, we still don’t know exactly what dark matter is. The different dark matter options which remain open to us can change its behavior in extreme situations – a dark star would certainly be one of these extremes. One of the options is that dark matter could serve as its own antiparticle, meaning that if two dark matter particles collide, they have a chance of converting themselves into high energy forms of light.

It’s by no means clear that this is how dark matter functions, and most simulations of the dark universe don’t allow for this dark matter-to-light conversion. But if it is the way that dark matter functions, then a high concentration of dark matter could produce rather a lot of high energy light, which in turn could heat any nearby gas and dust. This gives rise to bizarre approximation of a star, powered by dark matter destroying itself, instead of the fusion process which heats our own star.

There’s no observational evidence for these ‘dark stars,’ but it’s always interesting to know what kinds of objects might be hiding out in our Universe, given how much physics we already understand, waiting to be known.

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Why Don't Galaxies Just Pass Through Each Other Instead Of Colliding?

When two galaxies collide they eventually coalesce to form a single (larger) galaxy. By far most of the mass of a galaxy is Dark Matter which feels no friction and suffers not from collisions. Why then do not the dark matter components of the galaxies simply pass through each other and continue going? To suggest that the movement of these dark components is simply governed by the behavior of the visible portions seem to be like the tail wagging the dog.
NGC 6621/2 (VV 247, Arp 81) is a strongly interacting pair of galaxies, seen about 100 million years after their closest approach. It consists of NGC 6621 (to the left) and NGC 6622 (to the right). NGC 6621 is the larger of the two, and is a very disturbed spiral galaxy. The encounter has pulled a long tail out of NGC 6621 that has now wrapped behind its body. Image credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and W. Keel (University of Alabama, Tuscaloosa)

NGC 6621/2 (VV 247, Arp 81) is a strongly interacting pair of galaxies, seen about 100 million years after their closest approach. It consists of NGC 6621 (to the left) and NGC 6622 (to the right). NGC 6621 is the larger of the two, and is a very disturbed spiral galaxy. The encounter has pulled a long tail out of NGC 6621 that has now wrapped behind its body. Image credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and W. Keel (University of Alabama, Tuscaloosa)

Originally posted on Forbes!

Your typical galaxy does indeed have much more mass in its dark matter reservoir than it has in its stars. Unfortunately for us observers, stars are the only easily visible part of a galaxy. With the exception of a few nearby galaxies, where we can measure how much of this dark matter is hanging around a galaxy more directly, we have to assume that there’s some extra mass, but it's hard to know exactly how much. In general, there’s something like two to five times as much dark matter surrounding a galaxy as there is matter in stars and gas.

You’re also completely correct that the dark matter component to a galaxy doesn’t seem to collide with anything, and doesn’t feel friction or any kind of aerodynamic drag. As far as we can tell, dark matter only interacts with other kinds of matter (and with itself) through the force of gravity. So with this setup, you would expect two blobs of dark matter to simply pass through each other if they are on a collision course. And yet, we see that galaxies do collide; how is it possible to pull two objects together without any friction?

To get a galactic collision, you need two things. The first is to have two objects moving along a path where they will eventually pass near each other. However, if these two objects are moving too quickly relative to each other, they may just slingshot past one another, never to encounter each other again. This is called a flyby encounter, and happens a lot in clusters of galaxies. Galaxy clusters contain thousands of galaxies, all moving very quickly, and so each galaxy may swing past a number of others, but is moving too quickly to stop and merge with any of them.

This Hubble image displays a beautiful pair of interacting spiral galaxies with swirling arms. The smaller of the two, dubbed LEDA 62867 and positioned to the left of the frame, seems to be safe for now, but will probably be swallowed by the larger spiral galaxy, NGC 6786 (to the right) eventually. Image Credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)

This Hubble image displays a beautiful pair of interacting spiral galaxies with swirling arms. The smaller of the two, dubbed LEDA 62867 and positioned to the left of the frame, seems to be safe for now, but will probably be swallowed by the larger spiral galaxy, NGC 6786 (to the right) eventually. Image Credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)

So let’s say you have both pieces; your galaxies are on a collision course, and moving slow enough so they won’t go zipping past each other. The speed is critical. The two galaxies need to have some time to influence each other - the longer the galaxies spend near each other, the longer they have to be influenced by the other galaxy. But how do you slow down the galaxy enough to capture it, and eventually merge it into a single galaxy? The slowing is due to a process called dynamical friction. Even if the individual particles which make up a galaxy (which is mostly dark matter and stars) never physically touch each other, they still influence each other through gravity.

Galaxies on a collision course will swing past each other - let’s say they’re moving past each other like two people on escalators going opposite directions (not a bad approximation). The nearest stars in one galaxy pull gravitationally on the nearest stars in the other galaxy, and both sets of stars wind up slowing down as a result. It would be like reaching across the barrier and clasping hands with the person on the escalator going the opposite direction as you; that brief pull between you would pull both of you off balance. Both of you would get pulled towards each other, against the direction of your escalator. (I don’t recommend trying this experiment.) Over time, as every star does this with every other star, and the dark matter particles do this with every other dark matter particle, the stars in both galaxies will come to rest relative to each other. You’ve created a new, single galaxy.

Arp 256 is a stunning system of two spiral galaxies in an early stage of merging. The Hubble image displays two galaxies with strongly disrupted shapes and an astonishing number of blue knots of star formation that look like exploding fireworks. The galaxy to the left has two extended ribbon-like tails of gas, dust and stars. The system is a luminous infrared system radiating more than a hundred billion times the luminosity of our Sun. Image Credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University), and G. Ostlin (Stockholm University)

Arp 256 is a stunning system of two spiral galaxies in an early stage of merging. The Hubble image displays two galaxies with strongly disrupted shapes and an astonishing number of blue knots of star formation that look like exploding fireworks. The galaxy to the left has two extended ribbon-like tails of gas, dust and stars. The system is a luminous infrared system radiating more than a hundred billion times the luminosity of our Sun. Image Credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University), and G. Ostlin (Stockholm University)

This dynamical friction trick works great for individual galaxies, because both the dark matter and the stars are basically collisionless. Dark matter doesn’t interact with anything except by gravity, and the stars within a galaxy are so far apart that they’re incredibly unlikely to ever collide with another star. But galaxies aren’t uniquely stars and dark matter - there’s also gas: the stuff of nebulae. Gas is different from stars in that it can be compressed easily, and it collides with itself much more easily than the stars do. If you get enough galaxies together (as you do in a cluster), this gas can get pulled out of the galaxy, and heated to such a high temperature that it glows in X-rays.

So what happens if you take a cluster of galaxies, which is made of a huge mess of dark matter, several hundred galaxies made of stars, and a giant cloud of gas, permeating the whole cluster, and fling it at another cluster?

The Bullet Cluster. Dark purple indicates the location of the visible + dark matter mass. Red shows the X-ray emitting gas. Individual galaxies are seen in the optical image. Image credits: X-ray: NASA/CXC/CfA/ M.Markevitch et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/ D.Clowe et al., Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al

The Bullet Cluster. Dark purple indicates the location of the visible + dark matter mass. Red shows the X-ray emitting gas. Individual galaxies are seen in the optical image. Image credits: X-ray: NASA/CXC/CfA/ M.Markevitch et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/ D.Clowe et al., Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al

You get the Bullet Cluster, just above. This is one of the most famous clusters because it gave us really solid proof that dark matter was real, observable, and collisionless. The Bullet Cluster is actually two clusters in the early stages of merging together. We can see the two bundles of galaxies, on the left and right of the image. If you trace the amount of mass in each cluster, and then check where the X-ray gas is, you can see that the gas slammed into the gas from the other cluster like a brick wall - the stars and dark matter sailed right on through.

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Can we manipulate dark matter to go faster than light?

Is it possible that maybe dark matter may be the reason why there is gravity? That is, the more mass takes its place, the more it tends to squeeze mass therefore creating gravity? If so, can we invent something that contracts this dark matter by making it think that there is something very heavy then release it so that we skip a portion of space and keep repeating the process to reach a consistent speed?

With regards to fast travel, you’re actually not that far off from something that was proposed in 2011 by NASA employee Harold White!

It seems there’s a bit of confusion about dark matter and gravity, though. The phenomenon we call gravity is really just a distortion of space and time. Both dark matter and regular matter interact in the same way with space; the more of it there is, the more space bends. Dark matter is five times as plentiful but impossible to observe directly, so we have less of an intuitive grasp on it. But both dark and regular matter warp space, and the more heavily distorted space is, the ‘stronger’ the gravitational pull is. It’s true that in places with a lot of dark matter, you also tend to collect normal matter (this is how we think galaxies begin to form). And while collecting a little bit of normal matter will increase the overall amount of mass in a given region, thereby deepening the pucker in space we’re looking at, neither the dark matter nor the regular matter are responsible for ‘causing’ gravity. The combination of both forms of matter are responsible for causing the distortion in space and time that causes things to feel a gravitational pull.

As far as we know, we can’t make dark matter do much of anything, since it seems to only interact with other things in the universe through its disturbing affect on space (i.e., via gravity). However, what you’re after with your proposed method of travel is, fundamentally, a way to distort space, compressing the part in front of you, and releasing it once you’re past. This is precisely what every proposed (mathematically plausible) warp drive is trying to achieve. Since you create an expansion of space behind you, as the image above shows, you can almost surf space-time on an artificial distortion.

The main distinction is that instead of proposing to bend space by moving heavy objects around, it’s more efficient to bend space using the energy equivalent of that mass. Space does not like to bend, and the math used to predict how much energy this would require had always indicated that you would need to convert a mass the size of Jupiter entirely into energy in order to make it work. (Jupiter, for the record, is 317 times the mass of the earth, which weighs it in at 1.9 x 10^27 kilograms.) Hauling Jupiter masses around with your spacecraft is hugely unfeasible, so this idea had been mostly discarded. This is why people got very excited about Dr. White’s modification to the math in 2011. He found that changing the geometry of the bubble of surfable space would drop the energy required to force the distortion by factors of many thousands and into the range of plausibility. He’s currently trying to design a miniature version in the lab to make sure that his idea can work at small scales.

For the moment, even Dr. White’s model is still science fiction. Even if it does work, there may be other tangles to work out - a few theoretical physicists have worked out that this kind of travel might trap high energy particles inside the warp bubble, releasing them outwards in a potential death ray when you arrive at your destination - not quite ideal.

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