Gatephysics - 2 things that bother me

[AdamTM]

As some have pointed out, it is the only way the Stargate could work: creating a wormhole larger than an atom would be pretty much impossible.

It's still just replacing one impossibility with another. Creating fully functioning virtual parts of anything, that are connected LIVE with the real thing AND creating fake signals to go with it? Its as impossible as creating a wormhole the size of the gate.

Which begs the question, just how "big" is the buffer.
We know from the show that the buffer can hold half a Jumper in its buffer, which exceeds the mass and volume of the Gate by a factor of approximately 3.
So even if the information for the dematerialized jumper was inscribed on every particle of the gate, it would still miss 1/3 of the information. Also lets not forget its not enough to just count the atoms in the composition of the matter you transport, you have to know its position in space, its momentum (its conserved in gatetravel) and its exact quantum state (heissenberg compensator lol). So thats what ^3 more information than its physically possible to store?
AND NOW you have to simulate the circuitry of the Jumper, make fake signals and feed them through virtual wires. Thats as improbable, or even impossible than a full-sized wormhole.

Except of course if you invoke some kind of other mc-guffin, like the gate stores the information in hyperspace, or subspace, or has an infinitely good compression algorythm, that works in real time, and on amounts of data that exceed its physical storage capability...

JUST SAYING

[Quadhelix]

Also lets not forget its not enough to just count the atoms in the composition of the matter you transport, you have to know its position in space, its momentum (its conserved in gatetravel) and its exact quantum state (heissenberg compensator lol). So thats what ^3 more information than its physically possible to store?

Position and momentum are part of a particle's quantum state, so that is wrong. Also, there is the whole issue of delta-x*delta-p>h/(4*pi).


However, K^2 put forward the idea that the 'Gate could use quantum computing and use classical approximations of the atoms in the object. He suggests this because, apparently, the complexity of a classical system is proportional to the number of particles, while the processing power of a quantum computer is proportional to the square of the number of particles.

[AdamTM]

Position and momentum are part of a particle's quantum state, so that is wrong. Also, there is the whole issue of delta-x*delta-p>h/(4*pi).


However, K^2 put forward the idea that the 'Gate could use quantum computing and use classical approximations of the atoms in the object. He suggests this because, apparently, the complexity of a classical system is proportional to the number of particles, while the processing power of a quantum computer is proportional to the square of the number of particles.

I can accept that, however it just suggest a level of sophistication that is pretty improbable.
Especially the quantum state part as it would violate our known laws of physics or invoke the heissenberg compensator mcguffin from ST.

And yes i unnecessarily split momentum and position from the quantum state.

At least in ST as far as I remember beaming meant opening a subspace window for all the particles involved and sending them through subspace, which initially doesn't need that much computational power as materializing/dematerializing.

[Michael Jansky]

As some have pointed out, it is the only way the Stargate could work: creating a wormhole larger than an atom would be pretty much impossible.

Larger than an atom how? In thickness?

Well, that may be, but you don't have to step into the actual event horizon, do you? It would seem more convenient if there were a pad or chamber which you step into, where you're dematerialised all at once and then sent through a wormhole already as a signal. Of course, that would make it pretty much a Star Trek transporter using a wormhole for longer range and it is obviously not how stargates work in SG canon, but it would eliminate the gradual dematerialisation problem.

Why not?

Well, if you think about gravity as a warping of spacetime (i.e. in the Einsteinean sense), then this warping should not be able to pass through an event horizon of a wormhole, which, if I get it correctly, is a warping of spacetime in itself, just of a different kind. It could destabilise the event horizon and, if the Stargate were not able to compensate somehow, cause the wormhole to fail entirely, but there's no reason the Stargate should reproduce gravity on the other end. The event horizon would have to change its mass accordingly, which it shouldn't be able to do (if it even has mass, which I think unlikely). Of course, if one looks on gravity as a stream of particles ("gravitons") then those particles would likely pass through. There is a problem with gravitons however, as they do not seem to work at high energies. If a wormhole is anything like a black hole in the sense that a gravitational singularity is used to bend spacetime to create the two "ends", then the behavior of a graviton flying into one could not be accurately described, at least not with current theory. I can't really say what would it look like if string theory was applied, 'cause I'm not that good. :-)

[Quadhelix]

I can accept that, however it just suggest a level of sophistication that is pretty improbable.
Especially the quantum state part as it would violate our known laws of physics or invoke the heissenberg compensator mcguffin from ST.

Well, again, it is possible, rather than take the Quantum state of each particle (which, yes, cannot be measured without being changed), you instead take its classical position and momentum: this means that you have an effectively classical system of N particles. For something like a Puddle Jumper, I would expect N to be less than 10^28 (one gram of metal should contain ~10^22 atoms, one kilogram is 10^3 grams, one ton is ~10^3 kilograms, so one ton of metal should contain ~10^28 atoms).

For each atom, we have to specify things like charge, momentum, and position. Let us say that this results in 10^30 bits of data that the Stargate needs to store, process, and transmit. However, since the processing power of a quantum computer is apparently proportional to the square of the number of particles, then it should need only 10^15 "qubits" to take into account then entirety of a Puddle Jumper.

However, since individual atoms can be used as qubits, even if you used something heavy like Uranium, the processor needed to store a Puddle Jumper would have a mass of only 0.4 micrograms.

In other words, a quantum processor of a few milligrams should have enough processing power to simulate, at the atomic scale, then interior of BC-304, for example.

Well, that may be, but you don't have to step into the actual event horizon, do you? It would seem more convenient if there were a pad or chamber which you step into, where you're dematerialised all at once and then sent through a wormhole already as a signal. Of course, that would make it pretty much a Star Trek transporter using a wormhole for longer range and it is obviously not how stargates work in SG canon, but it would eliminate the gradual dematerialisation problem.

As I noted above, the Stargates would probably have computational power to spare.

Well, if you think about gravity as a warping of spacetime (i.e. in the Einsteinean sense), then this warping should not be able to pass through an event horizon of a wormhole, which, if I get it correctly, is a warping of spacetime in itself, just of a different kind.

A) Gravity is a distortion of spacetime.
B) There is still spacetime inside a wormhole.
A+B => Gravity can be transmitted through a wormhole.


Note that the event horizon itself is meaningless: it is the wormhole itself that is a spacetime distortion, the event horizon merely marks the "point of no return," if you will. Moreover, wormholes are gravitational phenomena.

[AdamTM]

Well, again, it is possible, rather than take the Quantum state of each particle (which, yes, cannot be measured without being changed), you instead take its classical position and momentum: this means that you have an effectively classical system of N particles. For something like a Puddle Jumper, I would expect N to be less than 10^28 (one gram of metal should contain ~10^22 atoms, one kilogram is 10^3 grams, one ton is ~10^3 kilograms, so one ton of metal should contain ~10^28 atoms).

For each atom, we have to specify things like charge, momentum, and position. Let us say that this results in 10^30 bits of data that the Stargate needs to store, process, and transmit. However, since the processing power of a quantum computer is apparently proportional to the square of the number of particles, then it should need only 10^15 "qubits" to take into account then entirety of a Puddle Jumper.

However, since individual atoms can be used as qubits, even if you used something heavy like Uranium, the processor needed to store a Puddle Jumper would have a mass of only 0.4 micrograms.

In other words, a quantum processor of a few milligrams should have enough processing power to simulate, at the atomic scale, then interior of BC-304, for example.

I can't check the facts on quantum computing, ill take them at face value.
This level of technology suggests that:

a. the whole of Atlantis is operated by a processor smaller than a grain of sand.
b. a spoonful of this processor should be able to simulate the whole known universe

With so much processing power to spare, you would think the possibilities are limitless, a stargate would be able to simulate whole universes.
I am not sure what is more improbable...
I know this is science fiction, but wow, if you assume this level of technology from the ancients, it seems like they wouldn't have a need to ascend anyways.

Oh and since you seem educated in the subject, out of curiosity, would a quantum computer be able to bypass the uncertainty principle?

[Quadhelix]

This level of technology suggests that:

a. the whole of Atlantis is operated by a processor smaller than a grain of sand.
b. a spoonful of this processor should be able to simulate the whole known universe

With so much processing power to spare, you would think the possibilities are limitless, a stargate would be able to simulate whole universes.

That is one thing that I don't like about stories with breakdown/reconstruct teleporters: the amount of processing power needed to make it work is borderline absurd.

Oh and since you seem educated in the subject, out of curiosity, would a quantum computer be able to bypass the uncertainty principle?

On the issue of quantum computing, I was quoting K^2 on the idea that the processing power would be proportional to the square of the number of qubits.

As for bypassing the Uncertainty Principle, I would say absolutely not. The reason for this is that the reason that there is an uncertainty in the measurement of quantum values is because the values themselves are not precisely defined. In other words, the Uncertainty Principle describes an aspect of the particle, not of our measurements.

[AdamTM]

As for bypassing the Uncertainty Principle, I would say absolutely not. The reason for this is that the reason that there is an uncertainty in the measurement of quantum values is because the values themselves are not precisely defined. In other words, the Uncertainty Principle describes an aspect of the particle, not of our measurements.

I read some article a year ago, of which i understood 10%, and it described a simple quantum computer in a lab that apparently solved "itself". Meaning the scientists didnt feed it any data, but it solved the function it was programmed for anyways.
Sounds like this principle could be used to program a (wave)function of a paticle and then let the q-comp solve it without feeding it any data.

PS: found the article, http://www.physorg.com/news11087.html

"Sometimes called interaction-free measurement, quantum interrogation is a technique that makes use of wave-particle duality (in this case, of photons) to search a region of space without actually entering that region of space."

[Quadhelix]

I read some article a year ago, of which i understood 10%, and it described a simple quantum computer in a lab that apparently solved "itself". Meaning the scientists didnt feed it any data, but it solved the function it was programmed for anyways.
Sounds like this principle could be used to program a (wave)function of a paticle and then let the q-comp solve it without feeding it any data.

I don't think that that is what they are saying: they had the data in the computer, but they were able to get the result of the computation without actually running the computation.

PS: found the article, http://www.physorg.com/news11087.html

"Sometimes called interaction-free measurement, quantum interrogation is a technique that makes use of wave-particle duality (in this case, of photons) to search a region of space without actually entering that region of space."

I looked up "interaction-free measurement" on Wikipedia; the article itself was a stub, but there were two interesting examples: the Renninger negative-result experiment and the Elitzur-Vaidman bomb-tester.

The gist of both of these is that a lack of measurement is still a measurement for the purposes of affecting the wave-function of a particle.

[AdamTM]

I don't think that that is what they are saying: they had the data in the computer, but they were able to get the result of the computation without actually running the computation.


I looked up "interaction-free measurement" on Wikipedia; the article itself was a stub, but there were two interesting examples: the Renninger negative-result experiment and the Elitzur-Vaidman bomb-tester.

The gist of both of these is that a lack of measurement is still a measurement for the purposes of affecting the wave-function of a particle.

Alright, thanks.

[Michael Jansky]

A) Gravity is a distortion of spacetime.
B) There is still spacetime inside a wormhole.
A+B => Gravity can be transmitted through a wormhole.


Note that the event horizon itself is meaningless: it is the wormhole itself that is a spacetime distortion, the event horizon merely marks the "point of no return," if you will. Moreover, wormholes are gravitational phenomena.

It was perhaps unclearly written, but I was referring to the wormhole, not the event horizon, being a warping of spacetime.

Also, I was under the impression that in the real world, we weren't even certain if wormholes can actually exist. And even if they can and are in fact as closely related to black (and white) holes as some think they are, we still have no clue what the conditions inside would be like. The spacetime inside a wormhole, for one, does not necessarily have to be the same one as out here. Intuitive conclusions like that the fundamental forces transmit through unchanged may not apply. We know EM signals get through, but that may as likely as not be due to the gate "translating" whatever the signal turns into inside back into normal terms upon arrival.

Now, obviously I was guessing about the gravity not being able to pass through, but it seems to me more likely than the changeless, lossless transmission seen in that black hole episode.

As for your A + B logical chain, I hate to pick and I don't pretend to be an expert, but from what I know about the state of current science, neither A nor B has been proven to hold (nor even accepted as scientific consensus, as empirical proof is next to impossible, especially for B). Also, I'm deifinitely not of the opinion that A+B implies C (that is to say, not *A+B deifnitely definitely does not imply C*, but rather *pretty sure it doesn't have to*). I will concede that B is most likely a necessary condition for C, but I doubt it is a sufficient one (even combined with A).


Oh, so that I do other stuff than just argue, nice one on the uncertainty principle. Some interesting highlights about the quantum computers, too.

To AdamTM: Another way to look at it is this: the uncertainty doesn't arise from the inability to measure precisely or without disturbing the object of measurement, but is an inherent property of the particle. It can not, by the definition of its existence, be measured exactly in the terms of position and energy. There are, however, ways to describe the particle that are not impeded by uncertainty. We can get sufficient and exact data about it, we just can't get certain properties in final values. That is however not necessarily a setback to scientific knowledge - it's just sort of a human bias to want to have everything expressible in a finite way. Look at Einstein - he made a huge contribution to physics, and yet the way of thinking required for his theories was viewed as extremely unorthodox at the time, among other things because he, too, said some things do not work as people generally tend to imagine they should.

[Quadhelix]

It was perhaps unclearly written, but I was referring to the wormhole, not the event horizon, being a warping of spacetime.

Well, actually, you are, in a way, referring to the event horizon. The reason is that, if spacetime inside the wormhole is different from spacetime outside the wormhole, there would have to be a point where the transformation occurs: where spacetime goes from being "normal" to being "wormhole-like."

It Also, I was under the impression that in the real world, we weren't even certain if wormholes can actually exist.

We aren't. However, if wormholes do exist, they would be described with General Relativity.

It And even if they can and are in fact as closely related to black (and white) holes as some think they are, we still have no clue what the conditions inside would be like.

We sort of do: although we cannot described the singularity at the center of a black hole, we can describe the rest of the interior - at least in principle. The main reasoning behind this is that there is nothing unique or special about the event horizon: to someone falling into a black hole, all falling past the event horizon means is that they now have no way out.

There is, however, no reason to think that the event horizon of a wormhole would be any different.

It The spacetime inside a wormhole, for one, does not necessarily have to be the same one as out here.

Except that, in order for the spacetime inside a wormhole to be different, there would have to be some transition point. To my knowledge, no such transition point has been considered.

To AdamTM: Another way to look at it is this: the uncertainty doesn't arise from the inability to measure precisely or without disturbing the object of measurement, but is an inherent property of the particle. It can not, by the definition of its existence, be measured exactly in the terms of position and energy. There are, however, ways to describe the particle that are not impeded by uncertainty. We can get sufficient and exact data about it, we just can't get certain properties in final values. That is however not necessarily a setback to scientific knowledge - it's just sort of a human bias to want to have everything expressible in a finite way. Look at Einstein - he made a huge contribution to physics, and yet the way of thinking required for his theories was viewed as extremely unorthodox at the time, among other things because he, too, said some things do not work as people generally tend to imagine they should.

This is very good.

[K^2]

For each atom, we have to specify things like charge, momentum, and position. Let us say that this results in 10^30 bits of data that the Stargate needs to store, process, and transmit. However, since the processing power of a quantum computer is apparently proportional to the square of the number of particles, then it should need only 10^15 "qubits" to take into account then entirety of a Puddle Jumper.

No. You are missing the true awesomeness of quantum computing. N qubits is equivalent to 2^N classical bits, not N^2. To replace 10^30 classical bits, you only need about 100 qubits.

And yes, storage system for the gate's buffer would most certainly have to be quantum. And since we know that there is a buffer, and that keeping your hand through the event horizon for extended periods of time without any harm is possible, we know that there is a simulated virtual environment in the buffer.

As far as neural impulses go, it is more likely that these are not supported or limited. That would explain why a person whose head is through the event horizon is effectively unconscious. (See SGA - 38 Minutes). This would result in body part through the gate merely feeling numb, not in pain. Reason for something like this might be due to limited simulation of chemistry. Which would make sense. For full support, you need quantum physics, and then you cannot store atom positions as classical information anymore, and you then require unfathomable amounts of quantum storage.

[Control_Chair]

No. You are missing the true awesomeness of quantum computing. N qubits is equivalent to 2^N classical bits, not N^2. To replace 10^30 classical bits, you only need about 100 qubits.

And yes, storage system for the gate's buffer would most certainly have to be quantum. And since we know that there is a buffer, and that keeping your hand through the event horizon for extended periods of time without any harm is possible, we know that there is a simulated virtual environment in the buffer.

Transcript from 48 Hours

McKAY:The crystals that retain the energy pattern before reintegration, they're not like magnetic hard drives.

CARTER: I know. They're crystals.

McKAY: You can't just ignore the laws of thermo-dynamics. Entropy dictates the crystals won't retain their energy patterns permanently. I've measured it. It's what's called quantitative evidence.

CARTER: I think the energy itself is unimportant past its initial imprint on the crystals.

McKAY: And this fantasy is based on?

CARTER: I suspect the Gate is storing its one's and zero's on the subatomic level within the structure of the crystals. So even though the energy is dissipating, the most recent pattern still exists.

[K^2]

Your point being? I don't really expect writers to understand how quantum storage works. It does work on subatomic level, though, using either electron excitation states, or nuclear spins.