We are lucky that most Sci-Fi technologies are nonsense

If you look into it closely the supposed physics behind most science fiction technologies is complete bullshit. This is actually a great thing since the cultural, military, and political implications of these technologies are absolutely disastrous. Science fiction rarely explores these implications instead opting to project current year values into the future. Let's think about the real results:

Teleportation: this is one of the most obvious disastrous technologies. You think immigration is bad now? Imagine a billion Africans having the ability to materialize in your living room, steal everything you own, rape your whole family, and be back to their village in time for dinner. There is no way that humanity operating under its existing genetics and culture could endure teleportation. Imagine a corrupt cop watching a woman sleep, imagine instantaneous movement of vast quantities of lethal drugs. In every conceivable way it would make crime that involves moving things around much easier.

Imagine what it would do to real estate prices. It would cause the cost of all real estate everywhere to basically be the same except for prime locations like buildings that overlook Central Park. One block away from Central Park the real estate prices would instantaneously drop back to the global level since only the views would have value.

Thankfully it's impossible to deconstruct the entire pattern of a person's atoms and then reassemble them. Doing this would also kill them and the person who came out of the machine would not be the same as the one going in. The transporter would kill the ability to keep people out of one's home. Repeated use of the transporter would also probably cause degradation of DNA patterns leading to horrific mutations in the species and the eventual extinction of humanity. Humans would probably create some sort of cult of the transporter that involved human sacrifice, since the machine is killing you every time you go through it.

Technological feasibility: 0%

Cultural impact: totally destructive

Usefulness: extremely useful for crime and moving things

 

Wormholes: these would require "exotic matter," which is just another way of saying something that doesn't exist but can be plugged into a math equation. There's no observable anything with negative mass and so no way these things could exist. Even if they existed going through one would shred everything that entered and what came out would just be a soup of atoms. In a sense most black holes are wormholes anyway that take you trillions of years into the future when they finally evaporate.

Wormholes would create time travel and the implication of that is being invaded by both humans and aliens from the future. Creating the smallest navigable wormhole would require something like the mass of Jupiter.

Technological feasibility: 1%

Cultural impact: none because it doesn't work

Usefulness: pointless, takes too much energy, shreds anything that enters it

 

Faster than Light Travel and warp drive are probably impossible. For complicated reasons it violates causality and leads to time travel paradoxes. Most scenarios require planet size levels of energy or negative energy (which is just a made-up math concept to plug into a formula). Really any kind of faster than light travel does this. Additionally, a warp bubble produces a bomb of gamma rays at the front of the ship as soon as the warp drive is turned off. This would kill all the passengers on board and anything in front of it. It would even fry the electronics. If warp drive existed it would probably serve more as a weapon than a means of transport. It would probably also be limited to less than or equal to the speed of light which makes it no better than really any other form of slower than light transportation. Even if it existed it would probably never be used since there are less energy intensive ways to get around.

Culturally, the implications of warp drive are basically galactic empires and the destruction of planets. Star Trek is presented as utopia but you'll notice in its own fiction various planets get destroyed or almost destroyed all the time. In Star Trek the Earth is almost destroyed when an alien probe shows up and wants to talk to whales. Then it almost gets destroyed by the Borg. Before that it almost gets destroyed by the Xindi. Vulcan and Romulus get destroyed in one alternate timeline. This is a surprisingly grounded scenario for a franchise built on utopian nonsense. A universe without warp drive is a much more libertarian universe where planets are forced to leave each other alone. One with warp drive is one filled with empires, vast political struggles for domination, and the never-ending specter of terror that comes from living on a big target like a planet. In fact in a universe with warp drive it would probably be best just to live in space and to keep moving. People would abandon living on planets altogether. Culturally, any kind of FTL automatically involves being invaded by aliens or at least extraterrestrial immigrants.

Hyperspace and "jump ships" are complete nonsense with no physics to back it up and have all the same military problems associated with them that any other FTL technology does. The biospheres of different planets are not compatible and merely shaking hands with extraterrestrials could do something like transfer bacteria to Earth that would convert the entire atmosphere into nitrous oxide or whatever. If aliens ever landed on Earth the consequences to the biosphere would be even worse than all the various invasive species that have been unleashed by global trade. If you think cats in Australia decimating wildlife are bad imagine something whose DNA is not even compatible with the existing biosphere and thus cannot be digested by predators. Imagine something that is like a walking prion disease and if a buzzard eats its rotting corpse it transmits some sort of wasting disease through the food chain. Nobody knows what horrors could be unleashed by mixing two biospheres and so it's great that this technology is nearly impossible, and even if possible, pointless.

Technological feasibility: 1% probability

Cultural impact: utterly destructive

Usefulness: mostly destructive

 

"Shields" and directed energy weapons for starships. The problem with shields is that once you have these governments will inevitably put them over entire cities. This abolishes the balance of nuclear terror that keeps the world from engaging in hypersonic nuclear warfare. You really don't want to speed up the ability to strike foreign countries since it gives them the idea that they might be able to hit their enemy blindsided before they can react and that's a very dangerous presumption. Hypersonic missiles are worrying in and of themselves but America has nuclear submarines and even if a first strike is possible without missile retaliation it is not possible to avoid retaliation by submarines. Defensive shields potentially change this calculus. In Star Trek they put their shields up and then proceed to tap each other repeatedly with antimatter weapons. This means they are showering each other with gamma rays in space. In real life such weapons would have negative consequences to any planet below the battle. Shields are a pointless escalation of warfare that makes everyone worse off than when they began.

And they are impossible! There is no magic substance they could be made out of. Plasma is the closest thing and it is a superheated material that might vaporize small things that touch it. But even a plasma shield can be penetrated by a big enough object with ablative technology. Just wrap whatever it is you are trying to protect in a giant heat shield and fly through, or fly through fast enough to survive. Making a shield hot enough to disintegrate everything would be pointless since that same amount of energy could be turned into a directed energy weapon. Concentrating that energy in one spot is far more effective than distributing it over a bubble. Navy ships already have Close-In Weapons Systems that defend them far more effectively than any energy weapon or shield ever could. Literally a rain of projectiles will always beat plasma. There is no such thing in physics as a "phaser" either. Antimatter weapons are also kind of pointless since they require trillions of dollars to produce a tiny amount of antimatter and the money could be better spent just building lots of nukes. It is possible to make tiny amounts of antimatter in particle accelerators and capture it but this is totally pointless and expensive. Projectile weapons will probably always be superior so while you might technically be able to make a shield out of plasma controlled by magnetic fields there's no point.

Technological feasibility: 0% for "phasers," 100% for plasma weapons/shields

Cultural impact: politically and militarily negative

Usefulness: pointless, nothing that a gatling gun can't handle better

 

FTL communication or Sophons like those described in the Three Body Problem. There is no way to inscribe an artificial mind onto a proton by unfolding it and then folding it back up. This is pseudoscientific nonsense. Also, quantum entanglement doesn't work over light years and even if it did a single fluctuation could break the connection and then you would have to send another at sublight speeds. "Subspace" communication is also nonsense. There is nothing in the laws of physics that lets you send anything faster than light, and for reasons I won't go into quantum entanglement simply doesn't work that way. Also it would cause causality paradoxes. If the technology worked as portrayed in science fiction it would probably change very little culturally it simply is impossible. All the technologies in the Three Body Problem are impossible except one. The droplet attack is impossible. The dimension folding foil is probably impossible since astronomers would observe two-dimensional regions in space and they don't. "Death lines" caused by "curved space propulsion" (warp drive) probably don't exist because warp drive will undoubtedly never exist. The one technology that is possible is a small amount of matter accelerated to near light speed.

Technological feasibility: 0%

Cultural impact: moderately positive

Usefulness: high

 

Kinetic kill weapons. The "photoid" is the one technology that is sort of possible. The reason it is possible is because the cross section of such a tiny object means that it is unlikely to run into any interstellar dust. But to hit a star you would have to hit it using dead reckoning from light years away since making course corrections is basically impossible. The photoid has no mass to shed and therefore no thrusters to change its own direction. The logistical problem of such a weapon is being accurate enough to hit something from light years away. This is like firing a bullet and trying to hit another bullet traveling in a different direction from the other side of the planet. The most likely outcome is that your photoid simply sails right by its target. But launching these things is cheap so an alien civilization could shower the entire solar system in these tiny kinetic kill weapons and we would basically be helpless to stop them. HOWEVER, you are talking about the amount of energy released by a small nuclear weapon at best and more likely a grain of sand dropped from a few feet up. If the kinetic kill vehicle was the size of a BB it would hit like a small nuke, but also have a much higher likelihood of running into space dust on the way here. Making it smaller would make it more accurate but more pointless, and you are assuming that you could even hit anything at such distances. More than likely such a weapon would just piss off whatever civilization it was intended to kill.

You can make larger kinetic kill vehicles and they are basically impossible to defend against unless you want to live as a swarm of rotating habitats around the Sun. Even then you might take some losses. The KKV will have to be big in order to make course corrections and that means it is more likely to run into space dust (which will explode with the force of a nuclear bomb) this means that it will have to go slower. KKVs will either be tiny and incredibly accurate or huge and slow with multiple warheads. The huge and slow ones are more likely to reach their target. The problem is that if you detect a civilization with radio signals and then launch a KKV by the time it reaches them they probably will have already evolved into a Dyson swarm or gone extinct through technological self-destruction. If you hit them it is actually next to impossible for them to trace where it came from, but it's kind of like, what's the point? It takes hundreds of years to get there. You either won't destroy them completely (because they are now a Dyson swarm) or they won't be worth destroying when you arrive (because they already destroyed themselves).

Technological feasibility: 50%

Cultural impact: devastating

Usefulness: dubious

 

So when you look at all this stuff you realize that science fiction is basically selling us a bunch of impossible technologies that would be absolutely terrible if they actually worked. The fact that physics doesn't allow most of this crap is probably the only thing keeping humanity and any other intelligent species in the universe safe from total annihilation. We're stuck with slower than light travel and kinetic weapons and honestly that's probably for the best since it means we can't immediately destroy ourselves or get destroyed by aliens showing up out of nowhere. The universe is set up in a way that forces everyone to leave everyone else alone and that's a feature and not a bug.