127 réponses à ce sujet

[adam_grif]

This is a followup thread to the one that got killed by the old forums closing down. The question (ideally a dev would answer but there's not much hope of that really) is as follows:

- Does Mass Effect Field technology conserve momentum, and if so, how?


As a little bit of background for those who are curious, momentum is the product of Mass and Velocity. So if you can just use Mass Effect fields to raise and lower the mass of an object (as stated in the codex), then you've altered it's momentum without a proportional change elsewhere. In a closed system (such as the universe) , momentum is always conserved. This is to say that it stays the same overall.

If it is conserved, how? If you use a Mass increasing field, does your velocity drop proportionally to maintain a constant momentum? If you use a Mass decreasing field does your velocity increase proportionally? 

If momentum is not conserved, then we can do something like the following: decrease mass to near zero, accelerate to a very high velocity, increase mass to higher than normal, collide with an object. The problem is that since you can inccrease your momentum trivially like this, you end up gaining a whole bunch of "free energy", that apparently comes from nowhere at all. So to violate CoM is to violate Conservation of Energy, too. You could use it to create perpetual motion machines that generate more energy than they use through this process.

If CoM is preserved, then why don't ships and stuff just use that to accelerate, then drop the fields to slow down when they get to a target? Instant reactionless propulsion system. In fact, missile payloads would be trivially easy to hit their targets / overwhelm GARDIAN systems, becacuse they would just use a small Eezo core to breeze past point defense at high relativistic velocities, then shove it in reverse to overwhelm the barriers (ala disruptor torps) and then detonate.

Discuss.

[tom.bleaker]

 It could work like the inertia suppression tech in the Revelation Space universe.

[adam_grif]

RS Inertia Supression tech violates CoM pretty directly, but violations of fundamental physical concepts are a dime a dozen in RS universe (like Cryoarithmic enigines operating in explicit violation of thermodyanmics).



Also, RS tech means that people trapped in the inertial supression bubble experiencce fundamental physiological effects, because the mass of their body being changed and the inertia being supressed means that fundamental bodily functions start breaking down. No such things are even mentioned in Mass Effect.



Also, the RS tech involves lowering the mass of some parts of the ship, but not others, so it's basically just like throwing stuff out the cargo bay doors to get more oomf out of your drive, except that you don't have to throw anything out. The ME field tech is clearly operating on the whole ship, and permits FTL travel through this.



They are operating pretty differently, I'd say, even if it was only in a black box sort of way.

[RyuKazuha]

Well, i'm not deep into physics, but you've to invest energy, to make E-0 eject a mass effect field. If that amount is similar to the amount "gained" in your example, it'd maybe not violate physical laws. Just a quick thought though.

Modifié par RyuKazuha, 21 janvier 2010 - 02:36 .

[tom.bleaker]

adam_grif wrote...

Also, RS tech means that people trapped in the inertial supression bubble experiencce fundamental physiological effects, because the mass of their body being changed and the inertia being supressed means that fundamental bodily functions start breaking down. No such things are even mentioned in Mass Effect.

See that's a serious difficulty in theorizing about ME tech. There is a great deal that is simply not mentioned.

[akintu]

adam_grif wrote...

If it is conserved, how? If you use a Mass increasing field, does your velocity drop proportionally to maintain a constant momentum? If you use a Mass decreasing field does your velocity increase proportionally? 

The codex entry on kinetic barriers explain that they function by creating a mass increasing field.  I'm guessing this means incoming projectiles hit these fields and have their mass dramatically increased, resulting in a drop in velocity, to something that is no longer lethal.

Which seems to indicate conservation.

Edit- actually the entry on kinetic barriers refers to "mass repulsing fields."  But...the entry on biotics explains that biotic barriers function by creating a mass increasing field.

adam_grif wrote...
If CoM is preserved, then why don't ships and stuff just use that to accelerate, then drop the fields to slow down when they get to a target? Instant reactionless propulsion system. In fact, missile payloads would be trivially easy to hit their targets / overwhelm GARDIAN systems, becacuse they would just use a small Eezo core to breeze past point defense at high relativistic velocities, then shove it in reverse to overwhelm the barriers (ala disruptor torps) and then detonate.

Trickier.  I get the feeling that there are limits to how low mass can be reduced.  The small arms, for instance, use a mass reducing field on their projectiles, but the limiting factor in weapon power is still considered "recoil."  If they were dropping mass to zero, or mathematically trivially close to zero, then it seems recoil would not be a factor.  I'm thinking along the lines of the systems not have the power to reduce/increase mass for the sort of performance you're talking about.

Though quick point I just thought about.  The SR1 Normandy could move using only its eezo core.  The Tantalus drive core was massive in proportion to the ship though, the size of a much larger ship's drive.  But...I don't believe it could handle FTL speeds with only the core.  Still needed its thrusters to push it.

Sovereign, however, (and correct me if I'm wrong), did not seem have visible thrusters.  Reapers are the master of this tech, so it would make sense that they would have some pretty powerful eezo cores.  Sovereign may have been capable of FTL with the core alone?

Anyway, I'll leave off there...

Modifié par alex_ladik, 21 janvier 2010 - 02:47 .

[flgator4evr]

Or maybe it is operating on a principle of physics we simply cannot understand as of yet. Or maybe it is like William Bell stated in the Fringe universe that Momentum can be differed some how.

[Hunt3rW0lf]

The whole principle of the mass effect theory seems to be based around dark energy, it could work by E-0 converting the mass into dark energy or dark energy into mass. Doesn't really deal with CoM though, however, a lot of the Mass Effect technology seems to be based around lowering the mass to obtain ultra-high velocities, so the momentum of the object may not necessarily have to change, the mass could go straight into veloctiy.

[Murmillos]

(I hate the new forums at times)

Modifié par Murmillos, 21 janvier 2010 - 02:54 .

[Murmillos]

Mass Effect works the way it does because it manipulates dark energy - the hidden energy in a another field dimension.
The use of the element 'eezo' allows energy to pass between the two - thus preserving the laws of a closed circuit universe.

adam_grif wrote...
If CoM is preserved, then why don't ships and stuff just use that to accelerate, then drop the fields to slow down when they get to a target? Instant reactionless propulsion system. In fact, missile payloads would be trivially easy to hit their targets / overwhelm GARDIAN systems, becacuse they would just use a small Eezo core to breeze past point defense at high relativistic velocities, then shove it in reverse to overwhelm the barriers (ala disruptor torps) and then detonate.

Dropping your mass only allows you to accelerate with less energy applied.  Even at zero mass, your vessel would only move according to the effects of the natural gravity around it.  Thrusts are still always required to move in the direction that you want to move in.

As for missiles, because eezo is still extremely rare and expensive to be wasting it on ordnance that is going to get vaporized -or may not even hit their target.  Even if you were to use the smallest amount of eezo possible - you would then need to build an extremely large power source to power that small amount of eezo to generate the current needed to make the effect even worth it.
In short, it could happen but they wouldn't be front line weapons, it would be the defense of earth protection weapons.

Modifié par Murmillos, 21 janvier 2010 - 02:57 .

[adam_grif]

RyuKazuha wrote...

Well, i'm not deep into physics, but you've to invest energy, to make E-0 eject a mass effect field. If that amount is similar to the amount "gained" in your example, it'd maybe not violate physical laws. Just a quick thought though.

Even if you could decrease the inertial mass of a starhsip to 0.000001 miligrams, it would still take infinite energy to reach light-speed and more-than-infinite energy to get past it. So it must be cheating in energy terms somewhere. The idea that you have to make up that energy in the elecctric current can't possibly hold.

tom.bleaker wrote...

See that's a serious difficulty in theorizing about ME tech. There is a great deal that is simply not mentioned.

Indeed. Mass Effecct fields are used all the time, and the crew doesn't go into stasis during FTL jumps. I would NOT want to be standing anywhere near the engineering deck, lemmetellya.

alex_ladik wrote...

The codex entry on kinetic barriers explain that they function by
creating a mass increasing field.  I'm guessing this means incoming
projectiles hit this fields and have their mass dramatically increased,
resulting in a drop in velocity.

Which seems to indicate conservation.

No, the entry doesn't say that at all.

http://masseffect.wi...22Shields.22.29

It says it creates a "repulsive field" that somehow repels masses that are going at certain velocities. It doesn't explain how these are created. The ME field entry says that ME fields are critical for creating them, but does not elaborate.

Trickier.  I get the feeling that there are limits to how low mass can
be reduced.  The small arms, for instance, use a mass reducing field on
their projectiles, but the limiting factor in weapon power is still
considered "recoil."  If they were dropping mass to zero, or
mathematically trivially close to zero, then it seems recoil would not
be a factor.  I'm thinking along the lines of the systems not have the
power to reduce/increase mass for the sort of performance you're
talking about.

Recoil should not be effected by mass reduction or increasing fields since it's based on the KE you throw into the object. If you're decreasing the mass and increasing velocity proportionally you should wind up with the same recoil, unless I'm confusing myself here.

Also, what happens when the projecties are no-longer subject to the masss increasing field? Do they fly out of the gun then regain their mass and reduce their velocity? Or is the effect permanent? 

Though quick point I just thought about.  The SR1 Normandy could move
using only its eezo core.  The Tantalus drive core was massive in
proportion to the ship though, the size of a much larger ship's drive.
 But...I don't believe it could handle FTL speeds with only the core.
 Still needed its thrusters to push it.

Are yo sure? I don't believe I read that it could move without expelling Remass anywhere.

Ok, I just read some stuff. The reactionless propulsion does not work by lowering mass, but by somehow coaxing te drive core into creating localiezd pockets of high-mass concentrations that the normandy "falls into".

Or maybe it is operating on a principle of physics we simply cannot
understand as of yet. Or maybe it is like William Bell stated in the
Fringe universe that Momentum can be differed some how.

Irrelevant. We can do black-box theory relating to how it works without having to understand the inner workings. We should be able to determine whether or not it violates CoM/CoE this way.

[Murmillos]

adam_grif wrote...
Also, what happens when the projecties are no-longer subject to the masss increasing field? Do they fly out of the gun then regain their mass and reduce their velocity? Or is the effect permanent? 

The effect lasts long enough until it hits a another mass that causes the micro mass effect field to collapse.  At which point your projectile hits the target at speed and orginal mass.  As the field collapes, the energy that you removed into dark matter space, returns - again closing the energy loop.  The weapon that fired the projectile still had to expend real energy in terms of heat and mild recoil.

[akintu]

adam_grif wrote...
No, the entry doesn't say that at all.

http://masseffect.wi...22Shields.22.29

It says it creates a "repulsive field" that somehow repels masses that are going at certain velocities. It doesn't explain how these are created. The ME field entry says that ME fields are critical for creating them, but does not elaborate.

Sorry, I edited to correct myself.  I was referring to the entry on biotics:  http://masseffect.wi...odex/Technology

It refers to "mass-raising kinetic fields."  Interesting that biotic barriers and kinetic barriers (generated by technological means) seem to differ in principle.  But based on the biotics entry, it does seem that mass is raised in order to reduce the velocity of incoming fire.

[Mr. Gerbz]

Finally, an interesting topic to read. I will add to the discussion later, when I have had some sleep, as it is pretty hard to focus at the moment.

[adam_grif]

Mass Effect works the way it does because it manipulates dark energy - the hidden energy in a another field dimension.

The use of the element 'eezo' allows energy to pass between the two - thus preserving the laws of a closed circuit universe.

No, Dark Energy / Matter is simply Energy / Matter that does not interact with electormagnetism, strong or weak nuclear forces. It only interacts with gravity.



http://masseffect.wi...iki/Dark_energy



The Codex entries state that Eezo does not pass energy and momentum between "two dimensions" as you say, but instead creates dark energy, which in turns raises or lowers mass. The specifics are not mentioned.



Please post sources for your arguments.

Dropping your mass only allows you to accelerate with less energy applied. Even at zero mass, your vessel would only move according to the effects of the natural gravity around it. Thrusts are still always required to move in the direction that you want to move in.

Strictly speaking, at zero mass it would not be interacting with gravity at all



You've made a statement, and that was one of the alternatives presented in the first post. What we're looking for here is canonical evidence to support it, either from in-game dialogue or codex entries.

As for missiles, because eezo is still extremely rare and expensive to be wasting it on ordnance that is going to get vaporized -or may not even hit their target. Even if you were to use the smallest amount of eezo possible - you would then need to build an extremely large power source to power that small amount of eezo to generate the current needed to make the effect even worth it.

In short, it could happen but they wouldn't be front line weapons, it would be the defense of earth protection weapons.

Eezo is already used extensively in small, disposable craft - fighters. Even if you needed enough Eezo to run a standard heavy cruiser to arm a frigate with missiles full of them, it would still be cost effective so long as that Eezo in missiles could take out a heavy cruiser.



In fact, you could just get a regular frigate and crash them into a dreadnought going at FTL and it would be game over man, game over. That's a highly cost-effective trade, like trading a pawn for a queen in a game of chess.



Don't forget that even today, it costs upwards of 70,000 US dollars to build a single guided missile. But so long as it can take out somethign more expensive than the missile itself, it's cost effective and will be utilized unless there is a cheaper way of doing it.

The effect lasts long enough until it hits a another mass that causes the micro mass effect field to collapse. At which point your projectile hits the target at speed and orginal mass. As the field collapes, the energy that you removed into dark matter space, returns - again closing the energy loop. The weapon that fired the projectile still had to expend real energy in terms of heat and mild recoil.

Do you have sources for this or are you just making stuff up?

Sorry, I edited to correct myself. I was referring to the entry on biotics: http://masseffect.wi...odex/Technology



It refers to "mass-raising kinetic fields." Interesting that biotic barriers and kinetic barriers (generated by technological means) seem to differ in principle. But based on the biotics entry, it does seem that mass is raised in order to reduce the velocity of incoming fire.

Mmmn, it mentions that it's using mass raising fields to imobilize and lock things down, not to block incoming fire. Biotic barriers aren't mentioned explicitly unless I missed it in my reading of the page.

[wikkedjoker]

I think what the mass relays do is convert you in to energy, as it sends you though a fold in space, a worm hole as it would be.

Than at the exit relay, you are converted back into your original mass, most likely with pattern buffers, that log the position of each molecule before you enter, and sends it to the exit relay instantaneously.



Much the same as how the stargate’s work.



So it would be easy to believe that matter traveling, would not gain speed or lose speed, but the speed would stay at a constant.

[akintu]

adam_grif wrote...
Mmmn, it mentions that it's using mass raising fields to imobilize and lock things down, not to block incoming fire. Biotic barriers aren't mentioned explicitly unless I missed it in my reading of the page.

My interpretation was that the "kinetic fields" mentioned referred to biotic barriers.  But now that you mention it, that may not be correct.  Barriers could also simply shred incoming projectiles (distortion, as it is mentioned).

It still seems to me that barriers work by raising the mass of incoming projectiles resulting in a drop in velocity.  That may be too great of a leap, but that is how I interpreted it.

[KBGeller]

I apologize as I skimmed most of the posts, but first I noticed a big misconception. You can increase mass without increasing velocity without violation laws of physics. It happens in particle accelerators/colliders. Once something starts approaching the speed of light, it starts gaining mass because E=mc^2 (or E=.5mv^2). since C is the constant, if energy increases the only thing that can increase is mass. This has been well seen and documented in colliders as i mentioned. If you want more details, im sure google or the wiki on the LHC will help you out.



Another misconception that wasn't explicitly stated, but may be inferred is that NOTHING, EVER can exceed the speed of light. EVER. The only way to travel faster than light is to bend/manipulate spacetime so that when you do travel at some speed, it APPEARS and I suppose you effectively are traveling faster than light.

[TheGuv]

Since I love silly debates like this, consider:

Both energy and mass conservation must be observed. 1/2mv^2 is the kinetic energy equation, with mv being the momentum equation. Place an upper limit of c on the kinetic energy equation with 1/2mv^2 = infinity and it becomes obvious that the mass increases. Both need to be conserved. If you suddenly decrease the mass, the velocity of the particle increases but the momentum and energy remain the same. The trick is finding a way to violate energy conditions to reduce the mass but not the energy. This requires negative energy which does violate those conditions.

While it makes little real physical sense, terms eezo would be best represented as producing a negative mass density with a negative energy density. For the duration of a barrel perhaps, you would greatly reduce the mass density within that local field, conserving the lost energy as negative energy. The exiting mass gains potential as it accelerates along the field, accelerating inordinantly until it eventually exits the field and regains its original mass at a greatly accelerated rate.

Exotic matter would also neatly explain anti-gravity (exotic matter repels under gravity). It does not however does not and cannot explain kinetic barriers simply due to their properties.

Exotic matter is advanced physics and unproven at this time.  I'm not going to go into it any further than that, but I was impressed at how close to real physics Bioware managed to make their sci-fi.

Modifié par TheGuv, 21 janvier 2010 - 04:33 .

[Hunt3rW0lf]

(Post above is on a similar line to below, didn't see it before I posted this)

With regards to the relays, I've always assumed that they hardly effect the ship at all and instead create a beam of super high mass through which the ship travels, due to the relativistic effects of such a vast amount of mass the distance between the relays tends to zero as space-time is bent. However I wouldn't really want to be in a beam which is essentially a black-hole string.

An explanation for the issues such as the barrier is that instead of effecting only mass, the Mass Effect works on gravity through gravitons. A kinetic barrier would therefore repel mass rather than attract it, a kind of negative mass or gravitational field scenario.

Modifié par Hunt3rW0lf, 21 janvier 2010 - 04:45 .

[anexanhume]

Recall that Newton's basic mechanics were not violated by Einstein, he merely came up with a more general form of the equations describing force and motion. My guess is that there are some unknown variables that would need to be taken into account to get a more general form of this equation.



The constant speed of light isn't actually constant and can be altered. Dark energy and matter is bound to have weird affects on relativistic equations I'd assume.

[TheGuv]

The speed of light can vary depending on the medium, but c (approximately 3x10^8ms^-1) IS constant.

[Iamoncewas]

I just have a note here ah I thought you had to apply a charge to ezzo to get a reduction or increase in the field it generated. Negative charge for mass reducing, and postive charge for mass increasing fields. ???? thus your static charge in the core and the need to discharge the drive core... thus your energy requirement,



Yes I know the higher in mass you become the more you energy you need to keep it there but since you are reducing the mass therefore less energy is required to get where you going right. ??? sorry just sayin, Ezzo is not an existing element therefore it has properties we don't have here with our elements on earth... Just an FYI



NOTE i am not a physist.

[Hunt3rW0lf]

 299,792,458 is the current known value for the speed of light in a vacuum. As has been said, this is the absolute maximum speed light can go, it can only go slower.

Yes, a current has to be applied to the element for the effect to work, like with Piezoelectric crystals but instead of a change in volume, it leads to a change in mass. However that only deals with the conservation of momentum, so unless matter or photons of some level of energy are released from the object there isn't anything to balance out the change in momentum.

Dark Matter and Energy are believed to have little effect on the universe or space-time, hence why we haven't been able to locate pockets of the stuff, to all appearances it isn't there. However, if a substance was able to bridge the gap then it could effect the universe.

[Iamoncewas]

I am just sayin if you reduce the mass with a charge to ezzo, couldn't you reduce the mass of an object to a point in which a light touch could send in fly hundreds of miles an hr. just sayin I can't throw a bulldozer, but a baseball, so by completely removing the mass of an object could also reduce the moment of an object as well which is why i can't stop a falling bulldozer but I can stop a baseball traveling at 98 miles an hr without dying by being crushed.