I am trying to fact check a consistent set of properties and applications for the titular unobtainium from the Mass Effect games in order to avoid introducing contradictions. Certain sources I read claim it wouldn't allow for the applications it is used for.

The in-game codex isn't detailed (it says it increases or reduces mass with positive or negative current and throws around "dark energy" like an accepted scientific term) and physics is not my area of expertise. I assume it works on principles similar to an electromagnet, but allows for the generation of gravitational fields with the strength of electromagnetic fields (×4.2E42 more force).

A block of the stuff is, I assume, bipolar and produces attractive or repulsive gravitational force based on the direction of current. Basically it combines the best parts of gravity and electromagnetism for the arbitrary manipulation of gravity, hence "unobtainium".

This unobtainium is noted in-game to have applications of:

  • casual flying vehicles (counteracting gravity?)

  • faster than light travel (Alcubierre drive?)

  • acceleration without thrust (create a gravity well in front of the vehicle?)

  • projectile weaponry using metal shavings (gravity railguns?)

  • repelling kinetic projectiles (force fields?)

  • moving objects at a distance

  • artificial gravity so everyone can walk inside spacecraft

  • counteracting intertia so spacecraft may accelerate without need for seat belts

  • for unknown reasons, leaving FTL drives running causes spacecraft to generate increasingly powerful lightning storms (EDIT: in-game explanation is that leaving FTL drives running causes spacecraft to generate "drive charge" even though this this violates conservation of charge)

Are element zero's properties internally consistent? Would it indeed allow the applications purported?

  • $\begingroup$ "Dark" energy is pretty much self explanatory it likes to keep a low profile, as for flipping the vector quantity (i.e. gravitational force) by using pressure different in scalar quantity (i.e. bipolar spatial dimensional crystal)... see how much handwavium in just one comment! $\endgroup$
    – user6760
    Oct 16, 2016 at 7:20
  • $\begingroup$ Nothing stated about this substance is remotely consistent with real physics. A clear alternative or enough data to come up with one is not offered. $\endgroup$ Oct 16, 2016 at 11:13
  • $\begingroup$ The question wasn't if it was consistent with physics. The question is whether it is consistent with ITSELF given the exception it carved out of physics. $\endgroup$
    – SRM
    Oct 16, 2016 at 15:13
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    $\begingroup$ Science based reality check for FTL?! $\endgroup$
    – Mołot
    Oct 16, 2016 at 17:36
  • 1
    $\begingroup$ There are no limits to handwavium :D $\endgroup$
    – Skye
    Oct 17, 2016 at 12:42

1 Answer 1


Game lore explanations

The lore of the game attributes to dark energy to both attractive and repulsive effects. And it says that the "element zero" is able to manipulate the mass of the objects (instead of manipulating gravitational fields as I described below). If so, it could be better understood as manipulating higg bosons. I find this explanation problematic because it seem to suggest negative mass for repulsion.

I found this description of the "element zero":

When subjected to an electrical current, the rare material dubbed element zero, or "eezo", emits a dark energy field that raises or lowers the mass of all objects within it. This "mass effect" is used in countless ways, from generating artificial gravity to manufacturing high-strength construction materials. It is most prominently used to enable faster-than-light space travel.

There are two relevant bits to take from here:

  1. it is not said to be a chemical element, but a material. It could be a particular isotope, or it could be a compound, or it could not even be baryonic matter.

  2. The quote says When subjected to an electrical current, that is, they are making a "wire" of the stuff. So, there is no reason to think that the material in it natural state has any noticeable gravitational effects.

The provided link about Drive Charge says:

Element zero FTL drives accumulate a static electrical charge when a vessel has been in FTL flight for some time. This charge steadily increases with the amount of time a vessel spends in FTL. Eventually, it must be discharged.

According to that, an electric charge is accumulated while traveling FTL. It doesn't seem to be an artifact of the FTL drive, but of the FTL travel itself.

Your question

Are element zero's properties internally consistent? Would it indeed allow the applications purported?

No, it doesn't work.

If we consider that "element zero" may also increase mass, then it could explain giving a strong gravitational field to an object. Reducing mass alone will never explain artificial gravity.

Increasing and decreasing mass of objects makes fine control harder, for instance, you could explain deflecting projectiles by increasing the mass of another object that then attracts the projectiles. But doing that would also affect other things in the surrounding.

Similarly, giving mass to an object in front of you so that you "fall" to that object won't allow you to go pass that object. Then you need to reduce the mass of that object again, and increase the mass of another object in the direction you want to go.

Also consider that if you reduce the mass an object to zero it will move at light speed. Alternatively you could understand not as reducing mass, but as reducing the influence of gravity, then you get weightlessness.

This doesn’t really explain repulsion of FTL travel either. Building an Alcubierre drive would still have the placement of matter difficulty.

I will not go into the problem of the electric charge from FTL travel here, because I'm saying that the game lore explanation is not good enough for FTL travel.

A better explanation

What this "element zero" seems to be doing is manipulating the gravitational field, to create either repulsive or attractive gravitational charges. So, it is making dark matter (attractive, but otherwise undetectable) and dark energy (the repulsive equivalent).

Using "element zero" would require some form of energy input. To remain consistent we would say that it uses electricity, and the output is an artificial gravitational charge (positive to be attractive and negative to be repulsive). The machine must be built in such way that allows directing such gravitational charge to the desired location.

The problem is: what happens when a charged particle arrives to an object made of "element zero"? We need to be able to make it so it can modify the surrounding gravitational field to create repulsive and attractive forces. So, there must be two ways to interact with it.

Given that the "element zero" is not a chemical element, I don't see any problem saying it is an anisotropic material that will react differently depending on the direction on which a current traverses it. That could explain how to create an attractive force by using current in a set of directions, a negative force in a different set of directions, and none at all in yet another set of directions.

Under this idea, you need use a different current direction to have a different effect, and you would need to actually rotate the system to direct it. The intensity of the effect would be linked to the power used.

Your question

Are element zero's properties internally consistent? Would it indeed allow the applications purported?


By creating artificial gravitational fields (both attractive and repulsive) relative to the machine that generates them can be used to move objects at distance. And it can be used to negate gravitational attraction, including those created using it.

Under the idea that it manipulates the gravitational fields relative to itself, it would be a way to create an Alcubierre drive. So it can explain FTL travel.

To explain an electric charge built up in an object traveling FTL using this method, such that it requires discharging it... I would have to say that the object captures charged particles during the trip※. A longer trip would lead to more charged particles being captured.

※Speculation: We could say that during the trip the ship pushes with it astrophysical plasma, just by it not having time to flow around the ship.

As a consequence of that electric charge, the ships would need a stronger insulation if they are meant to sustain larger FTL trips - as to prevent sparks from the outside to the interior of the ship that may cause damage. Also, leaving the ship after the travel won't be safe unless that charge is canceled.

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    $\begingroup$ I'm using real science with conservation and so forth. The point of unobtainium, in thise case the element zero, is that it has precisely the properties to power technology which is otherwise impossible (like personal force fields). I'm concerned primarily with the effect, not the cause, but I want the unobtainium to be self-consistent. For example, the Mass Effect codex states that FTL is possible because the mass effect changes the speed of light even though that doesn't follow from its original effect. $\endgroup$
    – Anonymous
    Oct 15, 2016 at 23:54
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    $\begingroup$ @Anonymous See updated answer. Just in case it isn't clear, I'm proposing a better explanation than that provided by the game. If your sci-fi is not in the Mass Effect universe, this is not a problem. Otherwise you may use it and say that the codex was wrong, inaccurate, or even intentionally misleading... and that can be a plot point in your narration. $\endgroup$
    – Theraot
    Oct 16, 2016 at 0:28
  • $\begingroup$ It doesn't remove mass but rather can "reduce" it (or "increase"). If mass of flooring and of a person are both increased by some controlled amounts, artificial gravity between the two might be more feasible... depending on inertial effects of increased mass. If I suddenly had 10Mkg of mass, I might find it difficult to start or stop moving. And if mass isn't massively increased, gravitational attraction shouldn't increase much. $\endgroup$ Oct 16, 2016 at 2:58
  • $\begingroup$ @user2338816 got rid of all intances of "remove" and added your workaround for artificial gravity if we say it can increase mass. $\endgroup$
    – Theraot
    Oct 16, 2016 at 15:36
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    $\begingroup$ @Anonymous updated. I don't know how large would be the charges accumulated by the FTL travel, yet I don't see the problem with that. If this is an issue, please elaborate on the question. Also, how hard do you want your sci-fi to be? You said, "I'm concerned primarily with the effect, not the cause", I'm not sure about that. $\endgroup$
    – Theraot
    Oct 17, 2016 at 14:05

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