Most "powerful" sci-fi weapon possible?

[MKI]

So I recently read "Death's End", which is the third book in the "Three Body Problem" series, or also known as the "Remembrance of Earth's Past" series. Without getting too spoilery, there are some heavy sci-fi weapons used in the book series that are reasonably based in in some kind of science. One aspect of the series is the fact advanced alien tech is very much beyond what we consider to be "advanced", and such a divide expands as the series goes on by significant magnitudes.

So it got me thinking, what is the most "powerful" weapon you could imagine, or have heard of in sci-fi that is at least kinda based in some science?

 

For those that already read this book, or don't care about spoilers, here's specifically what they "weaponize" in the book series: (HEAVY SPOILERS!)

Spoiler

Later in Death's End its found that advance alien civilizations essentially have weaponized the laws of physics itself, where stuff like the speed of light is "slowed" for defense/attack, dropping entire star-systems into what is essentially "black holes" or "black domains". Along with weaponizing space itself to "drop" enemies into a lower dimension, so from 3D to 2D, which is effectively undefendable. Furthermore the book also makes the notion that the universe was created with 10 dimensions, and the speed of light was infinite, but over time its "collapsed" into lower dimensions and slower speeds of light after multiple iterations of attacks and defenses both of which warped the laws of physics. Its also proposed that all these lower dimensions can't interact with our higher dimension beyond gravity, which offers an explanation of dark matter. 
 

I don't know how or if one could control the laws of physics itself, but it does seem like a pretty powerful weapon if such could even be possible to the point I can't really thing of a better one lol.

 

Edited May 27, 2021 by MKI

[KSK]

Perhaps it’s not the most physically powerful weapon (although it’s not exactly weak either) but a stable version of Star Trek’s Genesis device would be pretty psychologically powerful.

’Behold as I destroy your likeness, your culture, your people, and recast them in mine own image!’

[kerbiloid]

Bikini Space Armor of Ancient Amazons.

Mentally enslaves the enemy recruits before they get armed.

Edited May 27, 2021 by kerbiloid

[ARS]

I can think of GENESIS (Gamma Emission by Nuclear Explosion Stimulate Inducing System), from Gundam SEED. To summarize: GENESIS is a huge gamma ray cannon that uses nuclear explosions to produce a massive burst of gamma radiation, which is reflected back by an external alignment mirror and focused by a second mirror on the cannon to create a laser beam. The laser fired by GENESIS is sufficiently powerful that if it were to hit Earth, it would wipe out half the life on the planet. It causes human bodies closest to the shot to inflate and explode, even inside the ship. The external mirror is severely damaged in the blast and must be replaced for another shot to be fired. The GENESIS was protected by multiple layers of Phase Shift armor, which is capable of even withstanding a hit from a Positron Blaster Cannon, and could be concealed by Mirage Colloid. In other words, that's a giant cannon that focuses multiple nuclear explosions into a single devastating beam

For a defensive weapon would be Neutron Stampeder device, which actually isn't a weapon but a gigantic high-intensity neutron emitter mounted on a spaceship.  Mounted on a Nazca-class destroyer, it is nearly as large as the ship itself. It works by remotely controlling the movement of free neutrons to induce runaway nuclear fission reactions. When activated, the Neutron Stampeder emits a massive energy wave, which causes any nuclear weapons it comes in contact with to prematurely detonate. Unfortunately, the quantum fresnels fry themselves after firing, so the weapon can only be fired once

[Codraroll]

Anything that bends reality on a large scale or changes the law of physics handily wins this one, I think. If you're able to "switch off" the strong nuclear force in an area, for instance, you can essentially turn any matter into a rapidly scattering cloud of elementary particles, and there's no defense from it. 

[kerbiloid]

Anything that isolates the enemy in a pocket or a clone reality.

[Dirkidirk]

There is something called a pp wave of death, which is a "gravitational plane wave exhibiting a strong non scalar null curvature singularity, which propagates through an initially flat spacetime, progressively destroying the universe". it also moves at the speed of light, so you can't see it coming. I don't really know how this thing works, but if a being can somehow produce something like this, they can probably evaporate some planets or something.

Edited May 27, 2021 by Dirkidirk

[DDE]

@ARS's gamma ray weapon is smaller than Shklovskyi's graser.

Quote

Shklovskii believes that a Type II civilization should have no difficulty constructing a gigantic gamma-ray laser (or “graser“) operating at a wavelength of 1 Angstrom and at power levels of at least 10^15 watts. This Mining Graser (Figure 19.2) would have a forward aperture diameter of about 10 meters and could focus on a 10-km-wide spot at a star's surface from a safe distance of 10 light-years. (Unmanned automated devices can venture closer.) The Mining Graser will probably be “self-critical“ -- that is, an enormous nuclear reactor that emits most of its laser energy directly as coherent light.)

According to an astrophysical theory proposed by British astronomer Geoffrey Burbidge, a concentrated gamma-ray flux should cause exceedingly high temperatures to arise in the outer layers of a star. If this temperature was hot enough, a spontaneous supernova might result. It is estimated that a flux of 107 watts/m2 may be sufficient to initiate a supernova explosion.

Hold on, I have a call on Skype.

Spoiler

 

[SpaceFace545]

Maybe exterminatus from war hammer. It basically explodes an entire planet’s crust. 

[Hannu2]

Higgs field have non-zero minimum energy. Some physicists have speculated that Higgs field may be in some kind on metastable state and it may be possible that it decays to lower energy state. I have understood that if such transition begins it expands at speed of light and nothing can stop it. It would change natural laws drastically and all current particles and their interactions would change. It would be impossible to know before it happens because there are not known ways to send information faster than light. Predicted probability of such event is be extremely low and it is not known is it really possible.

Maybe you can write that some civilization (or cosmological level gangster boss) has a method to initiate such transition. I am surprised if no scifi author has already used it.

https://en.wikipedia.org/wiki/False_vacuum_decay

 

[Scotius]

• Lensman also gave us the Sunbeam; a whole star system altered to function as core, coil and vacuum tubes for a beam that directs the full power of the star into a fleet- and planet-annihilating beam. Lensmen and their rivals, Boskone, routinely flung planets at one another at relativistic speed in lieu of normal relativistic projectiles found in other novels. By the end they develop a way, both sides, to create wormholes that allow them to fire FTL planets at one another from intergalactic distances. Nevermind the fact that, originally, their "Super-Mauler" class battleships were created to kill relativistic planets in battle, and by the end both sides were producing them by the tens of millions and using them as frontline battleships. They mass-produced Death Stars! Ironically the Super-Maulers proved ineffective...because the Boskone forcefield tech was amped up before they were deployed, ergo they simply started using them as battleships instead. The Sunbeam was considered a stop gap against relativistic planet bombardment until they developed something better.
  • The FTL antimatter planetoid projectiles mentioned in the opening paragraphs? Yeah they start mass producing those as well. Including smaller ones designed to be launched from bomber squadrons, and whole fleets of them to be used as interstellar bombardment against enemy planets and star systems. This was also considered a minor footnote by the end, where their FTL planets launched from wormholes could destroy star systems from intergalactic distances.
  • The Lensmen at one point were thrown into another dimension where the laws of physics are different. After finally figuring out how to return to their home dimension, they went back to the other dimension and modified two planets to be thrown at Boskone. When they did, the "foreign" planets hit the Boskone planets at 15+ times the speed of light.

This is copied from TVTropes page:

https://tvtropes.org/pmwiki/pmwiki.php/Main/LensmanArmsRace

[SpaceFace545]

An AI would be the most powerful weapon. It would be able to exponentially improve onto itself until it can break free and when it does it would be thousands of times smarter and faster than us. Any action made by an AI at this level would have no countermeasure and we would likely be unable to comprehend it. A rogue AI at this state would have no purpose other than feeding itself so life would be obsolete. It would begin to hoard matter and transform stars into computers. An AI would try its hardest to decrease entropy and destroy chaos until everything is the itself. 

Edited May 27, 2021 by SpaceFace545

[Just Jim]

A teacup... hehehe

(sorrry, I couldn't resist)

[StrandedonEarth]

8 minutes ago, Just Jim said:

A teacup... hehehe

(sorrry, I couldn't resist)

It needs some really hot tea inside...

As to the OP, a scifi fave would be a relativistic planet killer: a large mass moving at a significant percentage of c

[kerbiloid]

Spoiler

Ever killed a dragon just by one throw?

[Scotius]

No, but once i dropped a boss with one sword swing. It triggered three different criticals at once: hit critical, sword special effect critical and boss own critical vulnerability to that special effect. It was two years ago, and I'm still chuckling when i recall that moment.

[Codraroll]

3 hours ago, SpaceFace545 said:

An AI would be the most powerful weapon. It would be able to exponentially improve onto itself until it can break free and when it does it would be thousands of times smarter and faster than us. Any action made by an AI at this level would have no countermeasure and we would likely be unable to comprehend it. A rogue AI at this state would have no purpose other than feeding itself so life would be obsolete. It would begin to hoard matter and transform stars into computers. An AI would try its hardest to decrease entropy and destroy chaos until everything is the itself. 

It's not much of a weapon if it destroys everything and can't be controlled. In this case it's even the opposite: even by attempting to create such a rogue AI, you give all your enemies immediate justification for doing their hardest to destroy you, because the universe would end if you succeeded. Then it's not a weapon, it's a big flashing target.

[DeadJohn]

TLDR: given technology that exceeds our current real world laws of phsyics, anything is possible.

FTL technology is a potential planet-killing weapon. A simple FTL missile impacting a planet, no warhead required on the missile just its speed, might set an atmosphere on fire, shatter the planet's crust, or cause massive tidal waves.

Teleportation technology is also very powerful, depending on which "version" of teleportation is used. Can you teleport a bomb directly into an enemy's ship or headquarters? Can you teleport your enemy into the sun? Can you send some might-as-well-be-magic device into a sun to make it explode?

Large scale matter transmutation is another near-unlimited technology. Convert the breathable oxygen into something else; quickly kill everyone yet leave their ships and cities available for you to take. Convert the water supply and blackmail your enemy to do as you order. Convert their ship hull into a radioactive material. Etc.

[Starhelperdude]

maybe a black hole bomb or smth. could be the most destructive weapon, as it's basically a supernova maker

[kerbiloid]

Kraken.

[SpaceFace545]

the Sci-fiernator 2000, it destroys everything and I mean everything God included. Bam, Zip, its all gone.

Also can this thread get moved into the forum lounge? @Vanamonde

[YNM]

If they can't move anywhere else really fast and/or cannot change their geodesic trajectory...

[kerbiloid]

A physicist with a red crowbar.

[Starman4308]

My vote's on false vacuum collapse.

Sure, you'll die too, but it'll be an unstoppable, near-light-speed wavefront that effectively nullifies chemistry as we know it by dramatically changing how particles interact... and also releasing tremendous amounts of energy along the way. It may well be that new processes, possibly new life, can evolve in a post-vacuum-collapse universe, but virtually everything that depends on how particles currently interact is kaput.

If it's possible, it will almost certainly happen in the extreme-far-future (i.e. heat death), potentially reheating a frozen universe to something which can once again sustain complex processes... but such a universe would behave quite differently from our own.

As an analogy: it is entirely possible that there was some sort of gravitational chemistry going on in the very early universe, maybe even life. If intelligent life evolved from that, and you described an atom to them, they would see it as a result of heat death, because those can only possibly form at ludicrously low energies and low densities, and would interact based on forces which aren't generally meaningful*. A post-vacuum-collapse state would be to us, as we would be to a hypothetical early-Big-Bang civilization.

*Due to the sheer abundance of mass in the early universe, the non-gravitational fundamental forces we are familiar with (electromagnetic, strong nuclear, weak nuclear) would've been irrelevant.

[kerbiloid]

The first domino(es) tile.

Spoiler

Others fall themselves.