Gravity gun meets physics

[rendle]

I'm no physicist, but if you accelerate a heavy object (such as a cast iron radiator) from stationary to 40m/s in under a second, wouldn't the recoil knock you backwards through the nearest wall? If so, I think this should happen in the finished game.

 

[Majestic XII]

Originally posted by rendle
I'm no physicist, but if you accelerate a heavy object (such as a cast iron radiator) from stationary to 40m/s in under a second, wouldn't the recoil knock you backwards through the nearest wall? If so, I think this should happen in the finished game.

The thing you shoot away is till in the air, so the air gets the recoil not you

 

[rendle]

Nuh-uh, the device which propels it gets the recoil, and you're holding that.

 

[Cleric]

this is very true, you would need to have some really big shock absorbers to account for the recoil, the inertia would be huge!!

either that or somehow break the laws of physics, whichever is easier....

 

[Calm_Blue_Ocean]

Well a gravity gun is of course total science fiction (and not good science at that - but a hell of a lot of fun). The Idea (I assume) is that you are in effect making the object weightless while you remain firmly in the grip of gravity. All that would slow the movement of the object would be air resistance. However, you would still need to overcome the inertia of the object, so yes there should be significant recoil.

On the other hand, if the gun were to function by increasing the force of gravity in front of the object while decreasing it behind, then the object would in effect propell itself and there would be no recoil.


Ahh, an interesting problem in theoretical physics. "Still say there's nothing to chaos theory?"

 

[Calm_Blue_Ocean]

Thinking about it a bit more, it can't actually be generating a gravitional field. Think about the ragdoll demonstration in the tech video. If you created a localized area of increased gravity near the 'doll's' ankle and then moved that field upwards it would not have the effect of lifting the body by the ankle. Instead, the body would attempt to wrap itself around that point, making a small ball.

However, several physicists have hypothesized that gravity actually has a particular nature - that gravity can be exerted through particles called gravitrons (kinda' like photons of light). How might this influence the inner workings of a gravity gun...hell, how should I know?!

My head hurts now.

 

[Calm_Blue_Ocean]

I believe some scientists have theorized that gravitrons might exert pressure....now we're on to something.

Perhaps some things are better left unknown. Let's just say that the good people at Valve have created some new form of physics that we mere mortals cannot hope to understand. Let's stand back, drool on our shoes, and anxiously await this fun new toy.

 

[kastro]

ok...people keep thinking that there is only 1 "gravgun". if you watch the videos you can see that they are two different guns. one of them can lift objects (as seen in the tech demo), and the other allows you to pick up objects and throw them (as seen in the strider video where he throws the letters F U at the strider).

its not just 1 gun with two different fire modes, they are separate models.

 

[Calm_Blue_Ocean]

Yes indeedy Kastro. I'm hoping they will both be in the game (as experimental weapons no doubt). I bet you get the blue tractor beam one first.

 

[neva]

YEah, I really think Calm_Blue_Ocean has a point... I think that the gun makes a gravitation field around the object, making it wight less.

and Kastro... Yes their is to diffrent Grav-guns ^_^

 

[_-_-SELAS-_-_]

Originally posted by kastro
ok...people keep thinking that there is only 1 "gravgun". if you watch the videos you can see that they are two different guns. one of them can lift objects (as seen in the tech demo), and the other allows you to pick up objects and throw them (as seen in the strider video where he throws the letters F U at the strider).

its not just 1 gun with two different fire modes, they are separate models.

Hey thanks for saving my time I was just about to write that, and the guns lokk very different o they cant be the same with 2 functions

 

[rendle]

Gravitation fields and reduced weight are all very well, but the issue here is mass and inertia. The reaction to the force required to propel that radiator up a flight of steps has got to go somewhere.

 

[Cleric]

do you really care gow it works just so long as you can throw tables into bad guys??

 

[rendle]

I don't think it shouldn't be there, I just think having the recoil to think about would add an extra dimension to the gameplay. Either trying to find something to brace against, or taking your chances getting thrown backwards.

Maybe they could make it turn-off-and-onable.

 

[ub3rbr0k3]

I don't think there are 2 gravity guns. The one used in the tech demo was just a tracter beam.

 

[loque]

as I said in a different post I think the things the gravity can handly is restricted to things gorden can pick up himself so no flying cars or bodys :/

and in the movie it prolly whas just a show off :bounce:

 

[MilkyMilky]

Gravity Gun Physics

Its entirely (theoretically) feasible that a gravity distorting gun could do such a thing without forcing the intertia change and thus momentum back through the gun projecting the gravitational field.

Imagine that the gun can actually distort gravitational fields over a localised area, of varying intensity.

So, to use the example of the guy picked up by the leg, just induce a gravitational field that produces enough 'pull' around the leg area required to lift the whole weight of the person.

This field would only operate on a severly localised area (around the foot, say) that it would it effect be 'pulling the leg up' - and the force it exherts exactly matches the force required to 'hold the guy up'.

Now lets tackle the 'throwing stuff' part of the video.

This could be accomplished by distorting the gravitational field in the line of fire you want infront of the object.

Picture creating a 'mini black hole' infront of the object for a tiny fraction of a second, in the direction you want it to go.

(I tried doing an ascii diagram - I'll do it in paint and attach it)

This 'mini black hole', if small enough, and close enough to the object, and with a short enough lifespan, would only seem to affect objects very close (the dresser), pulling them towards its centre with extreme gravitational pull.

In fact, assuming you could do this, it could be made much more accurate by actually moving the (mini black hole/gravitational distortion) towards the target at the same time, thus continually accelerating the object.

So, in summation, given gravitational distortion technology, entirely feasible, without any intertia feedback to the holder of the gun - the energy used to the propel the object comes from the gravitational pull of the distortion towards it, not from some momentum conservation event.

But what do I know, I'm drinking beer.

Edit: Oops, sorry about the filename mods - I didn't realise it would keep the filename.

 

[Calm_Blue_Ocean]

In regards to the propulsion theory, that is eaxctly what I said.

On the other hand, if the gun were to function by increasing the force of gravity in front of the object while decreasing it behind, then the object would in effect propel itself and there would be no recoil.

As for the ragdoll example, I have to disagree. The gravitational field would need to be very intense. If you hung a body by one foot and any other limb etc came close to that region it would also 'stick' very strongly. The gravitational field would decrease by the inverse square of the distance. A point would be reached where the pull of the ground and the pull of the new field would be cancelled out - making parts of the body effectively weightless. The body would not behave at all like it would if supported by a tensile force (which is how it is depicted). If you took a ragdoll and shook it using this system I fail to see how you could end up with anything other than a ball.

But maybe it's the sleep deprevation talking:cheers:

 

[Yakuza]

Originally posted by Calm_Blue_Ocean
In regards to the propulsion theory, that is eaxctly what I said.





As for the ragdoll example, I have to disagree. The gravitational field would need to be very intense. If you hung a body by one foot and any other limb etc came close to that region it would also 'stick' very strongly. The gravitational field would decrease by the inverse square of the distance. A point would be reached where the pull of the ground and the pull of the new field would be cancelled out - making parts of the body effectively weightless. The body would not behave at all like it would if supported by a tensile force (which is how it is depicted). If you took a ragdoll and shook it using this system I fail to see how you could end up with anything other than a ball.

But maybe it's the sleep deprevation talking:cheers:

I dont know but, if you reach down and pick up lets say a childs doll by the ankle and shake it around aren't you manipulating gravity, all the gun does is supply a different source of energy to manipulate gravity.

 

[ub3rbr0k3]

The one used in the tech demo is a tractor beam, not a grav gun.

 

[TrueWeltall]

Maybe it has recoil but has some kind of dampener like on a Barret m82?

 

[KiNG]

im sure that if u were a college professor that u would be able to support this theory or shoot it down in any case i did not take physics and dont know wut im talkin about as the force of gravity is manipulated isnt it possible since it is controlin the force of gravity that its is at all possible to control the recoil force which is projected on to itself, dealin with forces could be its main purpose but is commonly associated with lifting things up hence the gravity-gun. anywho nothin is possible it its invented as the world has seen time and time again . dont bother trying to figure things like this out when they are basic on sci-fi things that have to deal with the future. just because we dont have the answer now doesnt mean they wont have it then.

eadit: by golly i think iv solved it, should change my name to sherlock.

 

[Noj]

The two different gravity guns seem to me to be different versions of the same gun rather than 2 separate guns that will both be in the game. Something like: The beam gun is an old Alpha version that won’t be in the game, and the other gun is an updated Beta version that will be in the game.

I don't know anything about mini black holes or complicated gravity fields, but it seems to me that if you use a device to manipulate the earth’s gravity to move an object, it's the earth that suffers the recoil of that movement and not the weapon.
Rather than the weapon projecting force it is manipulating an existing force.

I don't know why I always get sucked into these kinds of discussions, we all know damn well that the gun works the way it does because that's the way it was programmed and lacking a "real" gravity gun we can't exactly claim they're right or wrong.

 

[neva]

Maybe the beam gun is just a demonstration gun to show up the wonderful ragdoll system. They dont show it up "in-game" on any video...

 

[SerialCarpens]

Whoa, never even though about that

BOY YOU GUYS ARE SOME SMART COOKIES!!!

 

[Calm_Blue_Ocean]

dont know but, if you reach down and pick up lets say a childs doll by the ankle and shake it around aren't you manipulating gravity, all the gun does is supply a different source of energy to manipulate gravity.

Nope, you are supplying a force that counters gravity, but you are by no means altering gravitational fields.

it's the earth that suffers the recoil of that movement and not the weapon.

If you push on something it is the object that does the pushing that recoils. If the gun worked in this way the force would be transmitted from the gun to you and you would be flung back into the wall (and the force would be transmited to the wall, and that force would be transmitted to the foundation, and that force would be transmited to the Earth).

Rather than the weapon projecting force it is manipulating an existing force

Yup, that was my second theory. If you move stuff by altering the gravitational fields around it (i.e. increasing the field in the direction you want it to go) then you would be able to do away with recoil.

The one used in the tech demo is a tractor beam, not a grav gun.

I would agree, it transmits force rather than changing gravitational fields (of course, what the heck is a tractor beam exactly?).


I'm not trying to pick this apart or belittle it. The fact is this weapon is very creative and will be a hell of a lot of fun to play with..I can't wait! I just love having theoretical discussions and playing devil's advocate - it's great exercise for your mind.

im sure that if u were a college professor

Nope, still working on my Ph.D. - it won't be long though (he says crossing his fingers)

Ok, me thinks I'm finished:cheers:

 

[neva]

Lets just wait.... ^_^ :cheers: :cheers:

 

[KiNG]

ok cool i gots a #2 man(right hand man)serial
and u could be my doctor/advise giver/smart guy
and by no means are u under me just as serial is not under me your my foundation that holds up an idea not me.
adn therefore u cannot object and indoing so is in violation of internet pact 5.43.2 article 46 section 3.7

/me stamps Blue's ass with red hot rod iron:cheers:
Edit:I am building an Army(ever see Fight Club,LOL)
oh and it is very had to agru something no one knows anything about but blue makes a hell of an agrument

Edit: i really wanna see wut valves explanation is and if they even have one the physics that the grav gun incorporates in real life or if they just says "grav-gun:futuristic gravitational manipulator"

 

[FireBall]

haha if the gun makes it inot singleplayer with unlimited ammo we could basically kill off the entire combine army with one radiator .....