Antimatter, Dark matter, -2 kilograms, etc

[Physics_Hacker]

Well, you can turn off realistic. Besides, in order to make any star blue, you can just increase the temperature. Of course, if you want to see a blue giant as part of a stellar life cycle, that's not possible, because it's not possible in reality either. If a star doesn't start out as a giant, it doesn't become one.

Oh I see, but how do you do that in the game?

Also, doesn't exotic matter look exactly the same as regular matter; just minus mass with anti-gravity properties (and white holes are light warping fake stars? Because I don't know about whether light has mass or whether there is a minus version of it...)

Antiphotons are photons. And, yes, exotic matter would look exactly the same, if it came in atomic form.

[Magnetarhyper4436]

anti-photons... I think you mean Exotic Photons^{[citation needed to figure out where this word came from]}
Also, if they don't exist on paper, then an exotic Earth would either be very bright or as black as a black hole. Because (anti)gravity can bend everything.

[Physics_Hacker]

anti-photons... I think you mean Exotic Photons^{[citation needed to figure out where this word came from]}
Also, if they don't exist on paper, then an exotic Earth would either be very bright or as black as a black hole. Because (anti)gravity can bend everything.

No, the antimatter version of photons are antiphoton, and both are the exact same thing. Same concept with gravity, except that some have theorized that antigravity is repulsive, not attractive, so things fall "up", so antimatter might have this property, but other than that, all antimatter is is opposite charges.

And an exotic Earth wouldn't be any brighter or darker than ours, everything work the same with antimatter, except that electrical charges are opposite, like I just stated. If I had a lump of anti-sulfur, and a lump of sulfur, in the same shape and size, density and mass, you wouldn't be able to tell the difference unless you're willing to let normal matter touch the antimatter sulfur and kill everyone on Earth just to make sure it's antimatter...

[Arian]

If I had a lump of anti-sulfur, and a lump of sulfur, in the same shape and size, density and mass...

To be exact, having those two lumps would be kinda hard without having some confinement made of antimatter for the anti-sulphur and one made of matter for the sulphur. It wouldn't be wise to bring the anti-sulphur close to anything that's not antimatter, because the complex structures play no role in the annihilation process and thus anti-sulphur would be fine just with annihilating any matter particle a counterpart of which can be found inside the anti-sulphur atoms.

The annihilation process converts particle-antiparticle pairs into photons (and a few other energetic but mass- and chargeless particles). Now if a photon and an antiphoton would meet, they would produce a pair of photons. This can only be right if photons and antiphotons are the very same thing or else the equation wouldn't work out.
Looking at this, you can say it happens either all the time or you can say it never happens. The effective difference is exactly zero. It is like claiming all matter (and antimatter) in the universe gets replaced by identical (or even the opposite kind of) matter (and antimatter) every infinitely small time unit. It might be, but it doesn't make a difference and there is no way to ever detect it.

While we are still puzzled by the effects of gravity being stronger than predicted (we introduced dark matter and dark energy as fudge to make our equations work again), it is more than bold to assume that antigravity could exist naturally somewhere. Introducing "bright" matter and "bright" energy would naturally result from that.
We would end up with a fudge and an "anti-fudge" and could as well drop both. Since the first fudge actually (mathematically) resolves an observable phenomenon, it would be counter productive to neutralize it with an assumption that is purely based on considerations about symmetry.

Perfect symmetry doesn't exist. Why not? Because perfect symmetry would be simply nothing at all. No particles, no energy, no universe, no big bang. Only with nothing existing anywhere, symmetry could ever be perfect. Or with everything being the same everywhere, which would be the very same as nothing being anywhere. Our universe is the result of spontaneous symmetry breaking. In other words: It is a blemish in perfect symmetry.

[Magnetarhyper4436]

I want to ask one thing, if there wasn't any asymmetry in the first place, wouldn't the matter-antimatter process keep repeating until there was a final asymmetry to create a universe filled with galaxies because the collision from the process would generate energy which would create an area densely-packed with energy so that the matter-antimatter collision would start over again and again?

Also, Anti-matter and Exotic matter are completely different Physics_Hacker, it's like trying to say that a Potato is the same as a Tomato. Anti-matter has opposite charges to regular matter which causes the matter to be attracted, but Exotic matter completely hates it's cousins and wants to fly away (because it has anti-gravity properties). Unfortunately, the universe doesn't like exotic matter and says: "BE GONE!" and it disappears. 

[Arian]

There must have been initial asymmetry because the universe as we know it is what remained from that. That means also that there is very few (as in none at all) natural antimatter left in the universe, because if there was some it would by now have collided with matter and produced photons.

What I was trying to say above was, that our universe might as well only have antimatter, since it really only depends on what side you are as an observer. We baptized matter matter because it is what we know. Had there been more of what we call antimatter at the beginning, we would be made of that and we would call that matter. If someone could replace all the matter in the universe with antimatter, we would be unable to detect it, like we were unable to tell whether we are on the "right" or "wrong" side of a mirror's glass pane if we switched places with our reflection.

If the matter-antimatter process is going on between photons and antiphotons it has absolutely no effect on anything. Since photons and antiphotons are exactly the same, the process makes (anti-)photons out of (anti-)photons. The reagents are the same as the product, hence there is no reaction at all.
The matter-antimatter process went on until all antimatter had found their matter and the both annihilated into (anti-)photons. The matter that didn't find any antimatter because none was left, is what the universe is made of. The (anti-)photons the universe is filled with are as old as that.

BTW: Potatoes and Tomatoes are actually related botanically

Anyway, if exotic matter has anti-gravity properties, the electromagnetic force as well as the weak and the strong force must still have some effect on its particles. assuming all (or even one more) of the forces are reversed for exotic matter, it simply can't exist in lumps or structures bigger than single particles, because it can't build nuclei or even atoms.
Let's assume all forces but gravity work the same on exotic matter as they do on "common" matter. It can't be built from the same particles as "common" matter, since those don't have any anti-gravity properties. You need atoms that are made of exotic particles then, particles that can't be predicted by the standard model of particle physics. Anti-gravity requires those particles to have anti-mass. This implies an anti-higgs-field which the universe simply has no room for as it would neutralize the higgs-field, which would make matter behave very different from what it does now. Gravity wouldn't work and hence anti-gravity would be a moot concept.
Exotic matter is an idea similar to opening the fridge door to have a look whether the light is out when the door is closed.

[Magnetarhyper4436]

Well can't exotic matter have anti-gravity properties? Because it doesn't make sense for a negatively massed object to just have the same properties as everything else... Maybe one day we might create an empty environment where theoretical stuff can thrive and survive. (Maybe these will be integrated in to the Advanced particle model to show whether "so and so" can be a reality.)

Also, if you know another language: Pomme & Pomme de Terre (meaning Apple and apples of the Earth;ie. Potatoes) are similar to matter and anti-matter. And the Potato-Tomato thing is just a pronunciation quirk that people get their heads wound up by.

[Arian]

The actual problem is that it is logically impossible to have exotic matter the way you describe it. Negative mass is simply not a thing, not even with antigravity. Antigravity would work on negative mass like gravity on mass because it is a doubled negation.

The logic chain here would be:
Negative mass causing antigravity (mass repulsion)
Antigravity working attractive on negative mass (mass attraction)
Mass attraction is gravity

Even if we create stuff with the properties you imagine, it would still be artificial and require quite some effort to stabilize. It would have no use in the "real world", because it couldn't interact with that without getting lost. The "empty environment" you mention is indeed needed to keep it from touching the universe we live in. What's the point in having something that can only be held and used outside of our universe?

I was really just trying a witty remark on the vegetable thing 

[Magnetarhyper4436]

The actual problem is that it is logically impossible to have exotic matter the way you describe it. Negative mass is simply not a thing, not even with antigravity. Antigravity would work on negative mass like gravity on mass because it is a doubled negation.

The logic chain here would be:
Negative mass causing antigravity (mass repulsion)
Antigravity working attractive on negative mass (mass attraction)
Mass attraction is gravity

Even if we create stuff with the properties you imagine, it would still be artificial and require quite some effort to stabilize. It would have no use in the "real world", because it couldn't interact with that without getting lost. The "empty environment" you mention is indeed needed to keep it from touching the universe we live in. What's the point in having something that can only be held and used outside of our universe?

I was really just trying a witty remark on the vegetable thing 

Hm... I guess physics is a bit un'BEAR'able. Ba-Dum Tsss.

[Arian]

Physics is about facts, but that doesn't mean it doesn't allow for surprises. Stuff like Antigravity, Exotic Matter or Tachions are just outdated theories proven to be wrong. Yet there is enough out there that waits to be discovered and nearly each time we find something new it is something we didn't expect.
Physics is no longer as easy as watching an apple fall or an iron ball rolling down a slope.  You need to take a deeper dive to come up with new ideas to prove right or wrong. It always was more like finding new questions rather than answers.

[Physics_Hacker]

Physics is about facts, but that doesn't mean it doesn't allow for surprises. Stuff like Antigravity, Exotic Matter or Tachions are just outdated theories proven to be wrong. Yet there is enough out there that waits to be discovered and nearly each time we find something new it is something we didn't expect.
Physics is no longer as easy as watching an apple fall or an iron ball rolling down a slope.  You need to take a deeper dive to come up with new ideas to prove right or wrong. It always was more like finding new questions rather than answers.

Tachyons still have a place, and are possible, that's like saying that String Theory is wrong, just because we can't detect things that would assure us it is the correct theory of the universe doesn't mean it's wrong. O like saying that Warp Drive is impossible, or that there is/isn't alien life. We just, don't, know.

[Gordon Freeman]

I TLDR'd this whole thread because Magnetar has no clue what he's talking about

[Arian]

Tachyons still have a place, and are possible, that's like saying that String Theory is wrong,(...)

Not the way they were postulated
Insisting that particles faster than light are possible, actually equals saying that String Theory is wrong, because it implies that special and general relativity are wrong. String Theory is pretty much based on the assumption that Einstein was right.
There almost certainly is alien life and as certainly as that there is even intelligent alien life and civilizations. There is only an infinitesimal chance that we will detect them or the other way around before we found a way to travel outside of our universe by tunneling whatever is beyond it or creating the "empty environment Magnetar mentioned as well as a "bubble" of our own universe within that.

And that would be a Warp Drive actually because it would "warp" not only space and time but pierce the universe and thus create a tunnel again. It would put a kind of pipe (containing our universe's environment) through a tunnel (containing not our universe's environment), producing a shortcut.
To do so, we would first need to learn a bit more about the very shape of space, so we can determine where the ends of such tunnels would be.
If M-Theory is on the right track, it might be as "easy" as finding a way to leave branes and go for another.

The biggest problem with all that is still the energy required and finding those solutions may as well put us back to the problem of lightspeed and the literally infinite amount of energy needed to travel faster than that.

[Physics_Hacker]

Tachyons still have a place, and are possible, that's like saying that String Theory is wrong,(...)

Not the way they were postulated
Insisting that particles faster than light are possible, actually equals saying that String Theory is wrong, because it implies that special and general relativity are wrong. String Theory is pretty much based on the assumption that Einstein was right.
There almost certainly is alien life and as certainly as that there is even intelligent alien life and civilizations. There is only an infinitesimal chance that we will detect them or the other way around before we found a way to travel outside of our universe by tunneling whatever is beyond it or creating the "empty environment Magnetar mentioned as well as a "bubble" of our own universe within that.

And that would be a Warp Drive actually because it would "warp" not only space and time but pierce the universe and thus create a tunnel again. It would put a kind of pipe (containing our universe's environment) through a tunnel (containing not our universe's environment), producing a shortcut.
To do so, we would first need to learn a bit more about the very shape of space, so we can determine where the ends of such tunnels would be.
If M-Theory is on the right track, it might be as "easy" as finding a way to leave branes and go for another.

The biggest problem with all that is still the energy required and finding those solutions may as well put us back to the problem of lightspeed and the literally infinite amount of energy needed to travel faster than that.

Most of that, at least to me, reads like complete nonsense. I wasn't interrelating them, just using examples -.-

[Magnetarhyper4436]

I TLDR'd this whole thread because Magnetar has no clue what he's talking about

Wasn't one of the rules: "Don't text-speak"? Also physics is confusing with the whole negative mass, alcubierre drive and other theory's.

[Magnetarhyper4436]

Tachyons still have a place, and are possible, that's like saying that String Theory is wrong,(...)

Not the way they were postulated
Insisting that particles faster than light are possible, actually equals saying that String Theory is wrong, because it implies that special and general relativity are wrong. String Theory is pretty much based on the assumption that Einstein was right.
There almost certainly is alien life and as certainly as that there is even intelligent alien life and civilizations. There is only an infinitesimal chance that we will detect them or the other way around before we found a way to travel outside of our universe by tunneling whatever is beyond it or creating the "empty environment Magnetar mentioned as well as a "bubble" of our own universe within that.

And that would be a Warp Drive actually because it would "warp" not only space and time but pierce the universe and thus create a tunnel again. It would put a kind of pipe (containing our universe's environment) through a tunnel (containing not our universe's environment), producing a shortcut.
To do so, we would first need to learn a bit more about the very shape of space, so we can determine where the ends of such tunnels would be.
If M-Theory is on the right track, it might be as "easy" as finding a way to leave branes and go for another.

The biggest problem with all that is still the energy required and finding those solutions may as well put us back to the problem of lightspeed and the literally infinite amount of energy needed to travel faster than that.

Most of that, at least to me, reads like complete nonsense. I wasn't interrelating them, just using examples -.-

I think we kind of need to move off from Einstein. Even though what he said was correct, it's just putting us into a non-existent box. Also, saying warp drives cut through space-time and rip through reality is just saying "What is the point of imagining wormholes and the concept of einstien-rosenfield bridges."

But don't worry, we will have enough research points to go looking into these things.

[Arian]

Most of that, at least to me, reads like complete nonsense. I wasn't interrelating them, just using examples -.-

Now that's some lazy answer.You were not interrelating your examples, but I did. If you feel I got it wrong, it would be courteous to point me at my mistakes instead of wiping the whole thing off the table.
Telling what makes you think Tachyons are possible would have been a start.

[Arian]

I think we kind of need to move off from Einstein. Even though what he said was correct, it's just putting us into a non-existent box. Also, saying warp drives cut through space-time and rip through reality is just saying "What is the point of imagining wormholes and the concept of einstien-rosenfield bridges."

But don't worry, we will have enough research points to go looking into these things.

Certainly Einstein is not the final answer to anything, but he did not put us in any box at all. He rather explained why our universe doesn't always behave like our intuition makes us expect.
Also I wasn't saying warp drives would cut through space. It's more bending (warping) the structure or shape of space. If you imagine a balloon and a fly that wants to go on the other side of it, the fly's warp drive would go through that balloon without hurting its membrane. It would rather hit the membrane and bend it through the balloon until it touches the other side, where the membrane needs to be connected to itself leaving the balloon intact but creating a tunnel (or Einstein-Rosenfeld Bridge or wormhole) through it.

[Physics_Hacker]

Most of that, at least to me, reads like complete nonsense. I wasn't interrelating them, just using examples -.-

Now that's some lazy answer.You were not interrelating your examples, but I did. If you feel I got it wrong, it would be courteous to point me at my mistakes instead of wiping the whole thing off the table.
Telling what makes you think Tachyons are possible would have been a start.

Well for one thing, I have heard that String Theory DOES predict tachyons even if they're not the way they might've originally been proposed, and even if not there's still nothing to say they're impossible, because we have no way of detecting them since they can never slow down past the speed of light.

I think we kind of need to move off from Einstein. Even though what he said was correct, it's just putting us into a non-existent box. Also, saying warp drives cut through space-time and rip through reality is just saying "What is the point of imagining wormholes and the concept of einstien-rosenfield bridges."

But don't worry, we will have enough research points to go looking into these things.

Certainly Einstein is not the final answer to anything, but he did not put us in any box at all. He rather explained why our universe doesn't always behave like our intuition makes us expect.
Also I wasn't saying warp drives would cut through space. It's more bending (warping) the structure or shape of space. If you imagine a balloon and a fly that wants to go on the other side of it, the fly's warp drive would go through that balloon without hurting its membrane. It would rather hit the membrane and bend it through the balloon until it touches the other side, where the membrane needs to be connected to itself leaving the balloon intact but creating a tunnel (or Einstein-Rosenfeld Bridge or wormhole) through it.

That's how a wormhole works but Warp Drives are completely different, they expand space behind a ship and contract it in front, to a point that causes the ship to move through "absolute" space without even traveling at all in "relative space", like riding a wave.

[Arian]

Well for one thing, I have heard that String Theory DOES predict tachyons even if they're not the way they might've originally been proposed, and even if not there's still nothing to say they're impossible, because we have no way of detecting them since they can never slow down past the speed of light.

Indeed bosonic string theory does predict Tachyons, while it knows nothing of supersymmetry nor of the main five superstring theories that succeeded that original string theory. It also fails to see that there are other particles than bosons, the fermions.
The most convincing fact about M-theory is that it kinda unifies the five superstring theories and supergravity. M-theory describes the area where the other theories overlap or mirror each other and become interchangeable. Because all the different theories predict rather strange and often impossible things at some point, it is considered more probable that beyond the boundaries of M-theory none of the six pictures reality although the maths can be done.
In that light, a Tachyon is mathematically possible but not physically. Pretty much like a sparrow that eats a ton of grain would weight a ton plus the original weight of the sparrow.

That's how a wormhole works but Warp Drives are completely different, they expand space behind a ship and contract it in front, to a point that causes the ship to move through "absolute" space without even traveling at all in "relative space", like riding a wave.

Mr. La Forge did a good job explaining that, except it doesn't work. You don't simply contract space without (even temporarily) removing mass/energy from it, because mass/energy is what expands (warps) it in the first place. To remove mass/energy from the universe you have to deposit it outside of it or destroy it, in both cases violating the law of conservation of energy.
There are different theoretical models of warp drives though that only share the name with the Star Trek one. Some physicists do like Star Trek even if it's fantasy.

[Physics_Hacker]

Well for one thing, I have heard that String Theory DOES predict tachyons even if they're not the way they might've originally been proposed, and even if not there's still nothing to say they're impossible, because we have no way of detecting them since they can never slow down past the speed of light.

Indeed bosonic string theory does predict Tachyons, while it knows nothing of supersymmetry nor of the main five superstring theories that succeeded that original string theory. It also fails to see that there are other particles than bosons, the fermions.
The most convincing fact about M-theory is that it kinda unifies the five superstring theories and supergravity. M-theory describes the area where the other theories overlap or mirror each other and become interchangeable. Because all the different theories predict rather strange and often impossible things at some point, it is considered more probable that beyond the boundaries of M-theory none of the six pictures reality although the maths can be done.
In that light, a Tachyon is mathematically possible but not physically. Pretty much like a sparrow that eats a ton of grain would weight a ton plus the original weight of the sparrow.

That's how a wormhole works but Warp Drives are completely different, they expand space behind a ship and contract it in front, to a point that causes the ship to move through "absolute" space without even traveling at all in "relative space", like riding a wave.

Mr. La Forge did a good job explaining that, except it doesn't work. You don't simply contract space without (even temporarily) removing mass/energy from it, because mass/energy is what expands (warps) it in the first place. To remove mass/energy from the universe you have to deposit it outside of it or destroy it, in both cases violating the law of conservation of energy.
There are different theoretical models of warp drives though that only share the name with the Star Trek one. Some physicists do like Star Trek even if it's fantasy.

But like I said, we have no way to detect them if they were real, so really we don't know, thy might exist anyway, because our theories are wrong or only apply "to certain situations", and we would never know because theories like String or M-theory are only that, just theories, because we have no way to actully detect anything different from normal reality that String or M-theory might predict without building a particle accelerator the size of the milky way.

...Just because that's the way it works in Star Trek does not mean that it's impossible, in nearly every place that I've ever seen Warp Drives explained  it uses that method. Also, you contract space, and so does everything else in the universe, because of it's mass, it's only a matter of controlling the way that space bends, then, by possibly releasing artificial gravitons once we learn how, that will cause space to contract in front of the ship, though I'm not quite sure how you could control, and speed up, the expansion of space behind a ship, without the harnessing of Dark Energy.

[Arian]

Really, there could be unicorns and fairies and singing cupcakes being undetectable for humans because they don't interact with "our world" (not trying to associate you with that, I only lack a better example at the moment). However, everything that does interact with our universe must be a part of it, or else it wouldn't be a universe anymore. A "multiverse" is quite possible and even very likely, but since we can never reach another universe or the other universe reach us, it's irrelevant.
What interacts with anything inside our universe, is somehow detectable even if we don't know how yet. Something that never has any effect on our universe and can't be affected by it, is not existing for our universe and our universe is not existing for such things.

I never said it is impossible because it is part of Star Trek. It's even a brilliant idea, very simple and effective, but fundamental physical laws don't permit it. The very name of the warp drive is a Star Trek idea so what wonder is it that others explain warp drives the same way?
By the way, did you know that the USS Enterprise NC 1701D has an "Infinite Improbability Drive"? It's shown on the wall displays Mr. La Forge passes at least once every second episode. It's a tribute to the Hitchhiker's Guide Through the Galaxy. As a fun fact, that kind of engine would theoretically be possible even (again with insanely high energy usage), but it would do some heavy damage to the universe as we know it.

Does mass really contract space? I think you are confusing that with gravity contracting/compressing mass.
Take the commonly used picture of the rubber membrane with the bowling ball put on it. Does the sinking in bowling ball contract the membrane? I would guess it rather expands it.
To contract the membrane or rather to make it contract, you need to remove the bowling ball. You will have to do so without using energy so you are not allowed to lift it. Destroying it won't help either, since that takes energy and leaves fragments. Not even annihilating it using an "antimatter bowling ball" would do, it leaves you with an enormous amount of energy which equals mass. You need to zap it out of existence and then zap it back in.
Once you solve that problem, your warp drive is working.

[Magnetarhyper4436]

I don't think "whatever doesn't interact with our universe is irrelevant" because the fact we have discovered something that solves the answers (i.e. Dark Matter) to whatever is missing in the equation. Besides, for years the Homo Sapiens has thought of anti-gravity hover boards, aliens on other world, being able to harness the stars, perhaps even making a giant galaxy that looks like a cookie! (Don't ask why I said this)

Moving on, What exactly do you mean by needing to zap balls in and other of existence to make a working warp-drive?

Also, I think unicorns, fairies and sinning cupcakes aren't real because: 1. Unicorns would either need a horn similar to that of a Rhino or a skeleton piece (but horns are unnecessary to horses) 2. Fairies would be similar to that of a 'daddy long legs' and would need to suck your blood to survive (which mean Fairy repellent could be widespread) 3. Cupcakes are lifeless combinations of different plants and would need the ability to (MRS GREN)

Depends whether what you believe is true or not.

[Arian]

Something that doesn't interact with our universe is something that has no effect on anything (including us) in our universe. In turn, it is not affected by our universe either. If you remove it, the universe would be no different and if you remove the universe, the "something" wouldn't change at all.
Dark matter was discovered because it has an (quite enormous) effect of gravity. To detect something you need it to have any kind of effect on something else, like reflecting light, having a mass or charge or spin to be affected by the four fundamental forces. It simply needs to have any property that has any effect on anything else. If that's not the case, how would you ever notice it? And if that's not the case, what consequences would its existence or nonexistence have for our universe? Or the other way around: What consequence would the existence or nonexistence of our universe have on it?

By zapping out of and into existence I mean completely remove every effect the ball would have on anything.
In the given case of the ball warping the rubber membrane (where the membrane represents spacetime), the membrane will only go flat (contract) if you remove the "sink-in" effect of it.
It's not a perfect analogy to the warping of space but try to think of a way to completely neutralize that effect. Remember, energy proportionally equals mass.
The warping effect cannot be removed, only transformed (i.e. moved). Just as if you would stand on the membrane and pick up the bowling ball. The mass of it would still work on the membrane because you would sink in a bit deeper as the ball's mass is added to yours. Even throwing it in any direction would make you sink in the opposite direction.
Only if you remove yourself from our universe by leaving the spacetime of it (i.e. by not touching the membrane at all), you can remove the effect the ball's mass has on it. The only problem is finding a point outside of our universe's spacetime to anchor a pulley to hold you while you pick up the bowling ball.

Even if that will hopelessly derail this thread:
I don't doubt or even deny possibilities but I claim that not all possibilities are necessarily reality. In other words: Not everything that is possible does actually exist.
A horse with a horn on its forehead is absolutely possible. That evolution never went that way with horses doesn't make it impossible but it simply is not a real thing. The horn would be no disadvantage and therefore any mutation like that would not go extinct because of the horn.
Fairies might have developed the ability to phase shift, just like some species can produce electric currents or change the pigmentation of their skin. It's possible but never became a real thing.
Singing cupcakes could as well resemble the shape of the eponymous sweets and be actually some sort of animal making sounds that remind us of singing.

What I mean to explain is: It's moot to claim something could exist if you add that there can't be any evidence for that claim to be true.
If you say there is a possibility that something exists but it is impossible to verify its existence, then that claim is true for everything that can never be observed in any way. And this "everything" is exactly what's irrelevant for us and our universe.

[Magnetarhyper4436]

Thanks Arian, for helping me to understand (especially with the cupcake-things).

Also, are theoretical objects allowed in US²? Or is it only for things proven to exist...

[Arian]

Why of course are theoretical things extremely important for US2. It's a lab model. It's supposed to provide the sandbox to try out theoretical stuff.
It might be a bit hard though to implement stuff you don't know the exact or even basic properties of. Basing everything on pure theories and even on theories which contradict proven facts will make the results of it pure fantasy. It's a computer sim. Garbage in - garbage out.
If you try out theoretical stuff in a realistic model though, you can at least find out whether it could fit in at all and maybe even how it could.

I only take a fighting stance if people insist there are things that cannot be proven to exist but at the same time they claim these things must exist because nobody can prove they don't.
It's a form of hypocrisy. Saying something is true until proven to be false, might seem positivistic at a glance but in fact it is exactly what I might be blamed for.
I claim it is true that what we know is right until we find evidence for the contrary. The difference is that I stick to what we know instead of what we could imagine.

Also any theory or even any idea deserves consideration and maybe even research. If we can't come up with valid arguments against it, it is very well worth some research. If all of what we know hints at such an idea being wrong however, it is likely that it is indeed wrong or at least that we lack information on how it could be right. If we lack that information, the idea is most likely not the result of a theory based on knowledge or observation but pure fantasy. That's not something bad, but it's kinda impossible to do serious research on that.

In the example of exotic matter, you need to provide the exact properties of it if you want to see it implemented or else the model would be wrong and so would be your observations. However, I am all for a simulation mode where you can freely change properties of objects even to unrealistic values.

[Physics_Hacker]

Something that doesn't interact with our universe is something that has no effect on anything (including us) in our universe. In turn, it is not affected by our universe either. If you remove it, the universe would be no different and if you remove the universe, the "something" wouldn't change at all.
Dark matter was discovered because it has an (quite enormous) effect of gravity. To detect something you need it to have any kind of effect on something else, like reflecting light, having a mass or charge or spin to be affected by the four fundamental forces. It simply needs to have any property that has any effect on anything else. If that's not the case, how would you ever notice it? And if that's not the case, what consequences would its existence or nonexistence have for our universe? Or the other way around: What consequence would the existence or nonexistence of our universe have on it?

By zapping out of and into existence I mean completely remove every effect the ball would have on anything.
In the given case of the ball warping the rubber membrane (where the membrane represents spacetime), the membrane will only go flat (contract) if you remove the "sink-in" effect of it.
It's not a perfect analogy to the warping of space but try to think of a way to completely neutralize that effect. Remember, energy proportionally equals mass.
The warping effect cannot be removed, only transformed (i.e. moved). Just as if you would stand on the membrane and pick up the bowling ball. The mass of it would still work on the membrane because you would sink in a bit deeper as the ball's mass is added to yours. Even throwing it in any direction would make you sink in the opposite direction.
Only if you remove yourself from our universe by leaving the spacetime of it (i.e. by not touching the membrane at all), you can remove the effect the ball's mass has on it. The only problem is finding a point outside of our universe's spacetime to anchor a pulley to hold you while you pick up the bowling ball.

Even if that will hopelessly derail this thread:
I don't doubt or even deny possibilities but I claim that not all possibilities are necessarily reality. In other words: Not everything that is possible does actually exist.
A horse with a horn on its forehead is absolutely possible. That evolution never went that way with horses doesn't make it impossible but it simply is not a real thing. The horn would be no disadvantage and therefore any mutation like that would not go extinct because of the horn.
Fairies might have developed the ability to phase shift, just like some species can produce electric currents or change the pigmentation of their skin. It's possible but never became a real thing.
Singing cupcakes could as well resemble the shape of the eponymous sweets and be actually some sort of animal making sounds that remind us of singing.

What I mean to explain is: It's moot to claim something could exist if you add that there can't be any evidence for that claim to be true.
If you say there is a possibility that something exists but it is impossible to verify its existence, then that claim is true for everything that can never be observed in any way. And this "everything" is exactly what's irrelevant for us and our universe.

The spacetime analogy everyone uses shows that space being bent "downward" is analogous space being contracted (What do you think a black hole is?  A hole or a mountain? it takes energy to get out of a hole but it takes energy to go up a mountain) Upward would be expanding space, negative gravity, or whatever name for the same thing you want to give it, though negative gravity isn't impossible, as all matter including gravitons have antimatter counterparts, but for things like photons and grvitons antimatter has no difference since there is no charge involved, but the net effect technically could be opposite.

[DiamondMiner10]

These are interesting

https://en.wikipedia.org/wiki/Strange_matter
https://en.wikipedia.org/wiki/Quark_star

[Arian]

The spacetime analogy everyone uses shows that space being bent "downward" is analogous space being contracted (What do you think a black hole is?  A hole or a mountain? it takes energy to get out of a hole but it takes energy to go up a mountain) Upward would be expanding space, negative gravity, or whatever name for the same thing you want to give it, though negative gravity isn't impossible, as all matter including gravitons have antimatter counterparts, but for things like photons and grvitons antimatter has no difference since there is no charge involved, but the net effect technically could be opposite.

Would you agree with me if I claim that the surface of a cone is bigger than that of its bottom circle? If you just thought 'yes', then you contradicted yourself.
Stretching is not expanding.
Also your pictures describe the very same thing: Climbing up a mountain is pretty much the same as climbing  out of a hole. It has no effect on the energy used for climbing whether you go for a summit or a brim. A valley can righteously be described as a hole.
A black hole is no hole at all, as per definition a hole is a nothing with something around it, while a so called Black Hole is a very massive something with a lot of nothing around it.

Gravitons don't exactly cause gravity, they mediate its effect. Just like Photons for electromagnetism or Gluons for the strong force. Now we have yet to find an antiphoton that causes identical charges to attract or an antigluon that will make atomic cores break apart.
That doesn't mean there can't be a particle that mediates antigravity, but it's unlikely to be the antimatter pendant of the graviton.

As for the "Strange Matter" links:
Thanks DiamondMiner10. The stuff described there is  probably what's inside a black hole, if not in a pure form, because the other particles of absorbed matter would likely not decay quite into strange quarks.
The actual body of the black hole might consist of layers though of which one could be said "Strange Matter".

[Magnetarhyper4436]

The stuff described there is  probably what's inside a black hole, if not in a pure form, because the other particles of absorbed matter would likely not decay quite into strange quarks.
The actual body of the black hole might consist of layers though of which one could be said "Strange Matter".

Objects squashed beyond schwartschild radius doesn't turn into a strange matter object. It's just something illogical to us; unlike neutron stars which consist of a baking neutron soup, a deluxe Quark-Gluon plasma(?) and some sprinkles of iron on the top (would be a nice supper for a black hole).

From what I have heard from the 'How the Universe Works' documentary (I will post the video soon), once through the event horizon, we speed towards light to the center but suddenly stop whilst spaghettification is happening and then returning to normal.