# Sci-fi Science: Physics of Impossibru: “Force fields”

Welcome to this fun little series, that will explore all the classic sci-fi tropes and attempts to turn them into reality with the ALMIGHTY POWER OF SCIENCE!

Today's topic is:

## What do we know?

Force fields are a common trope in sci-fi, from Star Trek to Star Wars, just around everywhere. We ging to have a hard time, finding out their exact properties as they vary by franchises, however, what seems to be general in their attributes are:

• They are capable of deflecting or dampening at least one attack-type
• If the power of an attack breaks it, it can be regenerated relatively quickly, assuming, that the user isn't dead yet.
• It can deflect attacks, even if the user doesn't perceive where they are coming from.

I think it's enough, now let's work out things from here. An angle gundam angel using it's AuTism Field. (source: Rebuild of Evangelion 1.0: You are (not) Alone)

## Our proposal

This solution is the combination of various answers from all across Worldbuilding StackExchange.

What's our greatest problem?

Kinetic energy. It's f@@cking hard to protect against it, but why?

If that thing breaks loose, we're boned. (source)

A physical law, delivered to you by Newton himself:

When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.

Ouch. That means, that no matter what, without deceleration nor distribution of force, you gonna feel that rock hitting you. But there is a way to dampen it.

F=ma

and what's more important:

p=F/A

So, we need to:

• Decelerate the projectile.
• Distribute the force over a larger surface.

In more extreme cases:

• Make the projectile explode, then decelerate the fragments.
• Or redirect the projectile (or the user).

## With that being said, what's our plan?

The plan is to overkill (over decelerate) the projectile. We can earn this by using the answer JDlugosz, and using out the flux pinning to pin these layers to the user's suit:

As you can see, the proposed shield:

• Decelerates the projectile a bit with the spongy material.
• Decelerates the projectile, when the magnetic fields and the conductors are moving.
• Spreads ou the impact force over the largest possible surface...
• ...Which is also has a few layers of the spongy material.

• Then the superconductor returns the parts of the layer to their original position, the framework repairs itself, ready to take the next wave.

The shield also could just simply use laser and thermal shock to break apart it's target to manageable pieces, then decelerate those.

What about the other damage types?

• chemical: There are many inert materials, I can easily incorporate them into the shield.
• heat: Still a problem (especially with continuous plasma beams).
• ionizing radiation: yay (though the suit might need a container and an in-built toilet for the stuff.)
• non-ionizing radiation: Reflective layers or if microwave, then heatsinks.

## Now, I want to ask you few things:

Could this work, if not then why?

If you want you can make improvements for this shield concept.

And remember: I want this series to be used by pretty much anyone, like a base full of working and fledged out shield concepts.

(can be discussed in the comment section)

Deactivating the shield seems a bit tricky, but here is a possible solution:

If we would cover the conductors with something that insulates it from magnetic fields and can be retracted, when switching to defense mode, then we could ensure, that the user wouldn't be slowed down when changing the position of the conductors and magnets. The other thing would be making the framework loose and flexible and what's more important, movable to other points (with having "joints", that can break when overstressed without shattering and can be detached, and moved to a location, where it's not in the way) so then we can squeeze our shield when doing things, also it would be possible to lower our defenses in order to pull a lever, attack etc...

• And this bullet-proof personal body armor is better than other types of personal body armor how exactly? Cheaper, lighter, thinner? Not to mention that chemical protection suits must by necessity cover the entire body head to toe and are extremely uncomfortable to wear for any length of time. Protection against microwave radiation (in those rare situations when needed at all) is fundamentally different than protection against beta radiation... – AlexP Mar 1 '17 at 21:41
• Isn’t this substantially the same as Hard sci-fi energy shields? If not, you should at least reference and build upon existing posts. And, we want to discourage answers that are essentially identical to what’s already been posted, which a reader of the new post might not be familiar with or remember. – JDługosz Mar 1 '17 at 21:43
• honestly I'd say you're probably looking at a bunch of layers for different damage types. For instance, it's pretty easy to deflect ionized particle beams from e.g. Star Wars blasters using EM fields, but those won't do anything to stop a conventional bullet. An end-all be-all shield would probably have to be a composite of many shields. – ocket8888 Mar 1 '17 at 22:21
• @JDługosz I immediately thought of that, I may VTC as duplicate. – Zxyrra Mar 2 '17 at 4:34
• Are you asking if the answer (voted +28, and accepted) to another post is right? Because that is what it sounds like you are asking. I suppose if I have to ask what you are asking, we should close for unclear what you are asking. – kingledion Mar 2 '17 at 4:54

Plausible Force Shields.

Force fields can be achieved through a combination of multiple systems targeting a specific type of threat. As none of the following layers are connected directly to host/ship they do not necessarily experience any ill effects Newtons 2nd Law. Even in the most harsh situations they just have to move with shields.

The outer layer consists of a supercharged plasma window, shaped into a dome or sphere by electromagnetic fields. This is hot enough to vaporize most incoming metals. A static supercharged plasma window for general purpose usage, and a manually controlled short range plasma window for directional threats, to be used as shields.

A secondary layer underneath contains millions of curved laser beams, producing a high-energy web that captures projectiles fast or powerful enough to bypass the plasma window.

A third layer consists of a "lattice" made from trillions of carbon nano tubes. These microscopic structures are woven together in an instant, forming a diamond-hard shell repelling objects missed by the other two layers. If necessary, this can be extended to cover a larger perimeter, at the cost of decreased strength. Conversely, it can be reduced in size to provide an even denser and more durable barrier. You can propagate the force around the host if necessary, without any disturbance to them.

The layers described above can protect against the majority of bullets, bombs and projectiles. However, they are almost useless against lasers. A fourth and final layer takes care of this problem. This uses photochromatic particles, which change their properties when exposed to laser light, effectively neutralizing most directed-energy weapons. Similar to sunglasses that changed color when exposed to sunlight.

• You should probably add the reference source for your answer, as it's the same of this one: Layered Plasma Window – BgrWorker Mar 2 '17 at 15:34
• Thank you, Michio Kaku, but I fear, that the plasma window's radiant heat will burn my face down if I use it for too long. – Mephistopheles Mar 2 '17 at 15:51

Couple possibilities:

Photonic Matter - It is possible to take photons (light), which are massless, and bind them together so they behave as if they have mass.
It may even be possible to arrange the photonic molecules in such a way within the medium that they form larger three-dimensional structures (similar to crystals).
If science was able to produce this at high enough densities, it may be possible to use it to slow/deflect other forms of matter.

Dark Matter - The name refers to the fact that it does not emit or interact with electromagnetic radiation, such as light, and is thus invisible to the entire electromagnetic spectrum. Although dark matter has not been directly observed, its existence and properties are inferred from its gravitational effects such as the motions of visible matter, gravitational lensing, as well as its influence on the universe's large-scale structure.
One theoretical source of dark matter are Strongly Interacting Massive Particles (SIMPs). If they actually exist, and if they could be produced artificially through super advanced science, then making a shield that can absorb kinetic energy could be possible.
As Dark matter does not interact with EM radiation in any way, this would be somewhat useless against lasers, unless the gravitational effects were enough to cause diffusion through lensing.

Utility Fog - Microscopic nano manufactured machines with arms that can extend out and link with each other in order to form structures. When needed they can lock together to form a solid barrier and absorb kinetic energy.

• Yep, I've implemented the utility fog (or at least something similar to the shield in addendum #01 – Mephistopheles Mar 3 '17 at 16:44