# Long range laser using wormholes

So, I was recently watching Stargate: Atlantis, and I saw a very interesting concept. In one episode, the villainous Replicators use the stargate network to fire what is essentially a high-powered laser at Atlantis. My question is, is this scientifically feasible?

For reference, the weapon in mind produces a small wormhole going between point A (the general vicinity of a quasar) and point B (the orbit of a planet). Massive amounts of energy proceed from point A to point B via the wormhole, and then proceed to the weapon's target (point C). The beam is not a "true laser" per se, so much as it is a massive amount of visible-light radiation from the quasar going through the wormhole.

• If you dont mind some energy loss (redshift), also this won't happen in Portal and Portal 2. Dec 4, 2019 at 3:25
• @user6760 why would traversing a portal redshift radiation? Dec 4, 2019 at 4:18
• Scientifically feasible and wormhole in one sentence? Dec 4, 2019 at 8:33
• Possible but why? Just wormhole the target into THE SPAAAACEEEEEE! Dec 4, 2019 at 8:46
• @MorrisTheCat Episode 1 of season 2. After using the coordinates Daniel found in another reality, they jump through and find they landed on a ship. Later on Hammond tries to use the same coordinates and fails. They also try to escape the ship using the gate and it fails because the point of origin is wrong after they leave the planet. The gate doesn't work again until the very end where Daniel uses Earth as the origin. At this point the Earth now has 3 gates and is promptly forgotten :D Dec 4, 2019 at 15:47

Wormholes aren't forbidden by relativity, which isn't quite the same as "scientifically plausible".

If you were able to make a wormhole, then you'd be able to pump energy into one end and get energy out of the other end. Exactly what comes out of the other end rather depends on the nature of the wormhole metric. Given that wormholes may be mathematically possible but no-one has worked out a way to make them physically plausible, you can handwave that as you see fit. Do you want wormhole lasers? Sure, you can get wormhole lasers.

Remember that lasers aren't infinitely thin, and the throat of a wormhole is of a certain size. You can't fire a really fat beam of laser light down a really skinny wormhole. This may limit the useful range of the beam as it exits the wormhole due to diffraction limiting effects.

Finally, just because the wormhole would plausibly let you avoid the FTL issue by providing a shortcut between two points, doesn't mean that you can't just materialise a wormhole mouth at an arbitrary point in space. You need to carry one mouth to your target first (assuming that it possible, with whatever wormhole design you've settled on), and then shoot your laser through the other mouth. Being able to materialise a wormhole anywhere you like, such as by a distant target, implies FTL and that quickly totters off into the realms of implausibility and/or inconvenient things like time travel. So you might not want to do that, depending on how hard your want your scifi setting to be.

• This raises the terrifyingly technical question “Would a laser shone through a thin wormhole diffract?” Dec 4, 2019 at 12:25
• Also worth pointing out how easily the weapon was defeated in the show. "it can't move, let's put a rock in front of it" Dec 4, 2019 at 15:09
• Assuming that you're using previously constructed wormholes as the OP's Stargate example does, the main benefit to something like this that I can see is basically allowing you have to have small warships that carry one end of the wormhole, and the actual weapon safe on a planet somewhere. This would allow fairly small warships to act as the 'muzzle' for a much larger weapon without actually having to spend energy carrying the entire weapon around. It's a slick idea imho. Dec 4, 2019 at 15:23
• @MorrisTheCat don't forget the super gate to mini gate trick. So if you fired a huge laser into a super gate, and the other side was a mini gate, does it get condensed? And is the opposite true? Fire a tiny beam into a small gate, and output a huge beam from a giant gate? Dec 4, 2019 at 15:34
• @MorrisTheCat It's slightly suggested that the gates did increase the energy. To start a super gate, they needed all the energy from a planet. But somehow the super gate was started by a small gate sitting near a black hole. Which suggests the little gates unlimited energy was expanded to fit the big gates energy requirements. If that is the case, you could make a telescope like system to keep powering up the beam. Scary Dec 4, 2019 at 15:40

Reality check, if you can create worm holes anywhere. What do you need a laser for? Just create a wormhole that links from a black hole or star gravity somewhere, and put the other end inside the thing you want to destroy.

A laser is a waste of energy if you can already create worm holes. And that episode in particular was pretty inconsistent and had the characters tossing idiot balls around.

Remember they couldn't move to the other side of the planet because the portable gate would follow them. Except the portable gate couldn't get around a rock in front of it?

When gates are held open by incoming energy, they can be forced to jump to another gate by detonating a nuke next to them, they forgot that part?

• Thanks. I am not looking at that particular episode so much as the general concept. Also, I specified in my question that this isn't a "true laser", as its just funneling the energy from a quasar at the target. Dec 4, 2019 at 15:44
• "When gates are held open by incoming energy, they can be forced to jump to another gate by detonating a nuke next to them, they forgot that part?" Well, not exactly. They were unable to do that because the gate was shielded from attack. Apr 29, 2020 at 23:56

There are a couple of potential issues and also potential benefits from this scenario. As noted by others wormholes, in theory at least don't (except in certain specific circumstances) violate the laws of relativity. So assuming they exist and assuming their internal structure doesn't somehow disrupt the path taken by photons traveling through one your laser is potentially a 'goer'.

The key problem is targeting i.e. how do you control where a wormhole opens at the other end and once its open how do you keep in stationary relative to the target. In the Star Gate franchise the gates at either end stabilize the wormhole. I haven't seen the episode you refer to but the question becomes how do the Replicators do it when as far as I'm aware Ancients couldn't. Firstly you have to be able to precisely calculate the relative distance and position of the target from your end of the wormhole across light years of distance. Then to complicate matters the planet Atlantis is on orbits it's star and the planet itself rotates on its axis. So you'd have to be able to constantly adjust the position of the exist in tandem with the motion of the target (and your end is in motion relative to the target as well just to complicate things further).

The plus side is that you could use the same technique (poring energy through a small wormhole) to power any ship or device anywhere in the cosmos you wanted. No need for power generators at the other end at all. Just build huge power stations somewhere at the heart of your Empire and power everything from home.