Simply time travel deeds

[VSHARMA]

Here’s how its works..........

You can dial the Stargate once anyway in the Universe & and go to any time in the past

You can't travel back to the present and you can never leave your destination.

What kind of Deeds would you do?

Here’s a example...

Go to the Goa’uld homeworld (where symbiotes lived) before system lords and throw the Stargate in the Water so the Unas/Goa’uld can never leave they planet.

[K^2]

I realize that's not the point of the question, but just FYI, it is impossible to alter history by traveling to the past. I hope I don't need to go into details. Time travel is a bit complicated.

On the slightly more related note, I wonder why Ancients didn't build in time-traveling capabilities. Seems like it'd be relatively easy to do. A wormhole can connect two points at different times just as well as it can connect two points in different places.

[Jack_Bauer]

I realize that's not the point of the question, but just FYI, it is impossible to alter history by traveling to the past. I hope I don't need to go into details. Time travel is a bit complicated.

That is only one school of thought

[supersoldier34]

That is only one school of thought

It's only a hypothesis at best too.

[Jack_Bauer]

It's only a hypothesis at best too.

Indeed. One without logc in my humble opinion compared to theories relating to creations of alternate timelines when hypothetical time travel takes place.

[K^2]

That is only one school of thought

So is Evolution and Chemistry. Just because some people don't know what they are talking about, doesn't mean that we don't know what's going on.

We have models with very definite predictions about time travel, down to at least two distinct methods of "How-to". Both the General Relativity and Quantum Mechanics have been verified to an incredible degree. They are full fledged theories with better experimental support than just about anything else. To call these predictions "hypothetical" is absurd. These are predictions of a well established theory.

ndeed. One without logc in my humble opinion compared to theories relating to creations of alternate timelines when hypothetical time travel takes place.

Alternative timelines aren't created. They already exist. All of the possibilities are already there. I could simply say that you "switch" to a different timeline, but that's not entirely so. It's far more complicated, and I really don't wish to go into details, because you don't have a background in relativistic QM, and it'd be a waste of time.

[Jack_Bauer]

We have models with very definite predictions about time travel, down to at least two distinct methods of "How-to". Both the General Relativity and Quantum Mechanics have been verified to an incredible degree.

When did they send someone to the past and back?

[K^2]

When did they send someone to the past and back?

There is a number of interactions in subatomic physics that extend through time. But that's not even the point. The models themselves have been tested, and these models make predictions.

[thekillman]

it is possible to alter the past, but then you wont create a time paradox. by going into the past you most likely overwrite the future.

one of the things that really bugs me:

If the Metaverse exists, then it calculates every possible future outcome.
if the Multiverse exists, it calculates the outcome of all physics settings.

those two combined would mean that the Ultraverse, so to speak, the multimetaverse, would be calculating every possible outcome of everything.

[Splitsecond]

We have models with very definite predictions about time travel, down to at least two distinct methods of "How-to". Both the General Relativity and Quantum Mechanics have been verified to an incredible degree. They are full fledged theories with better experimental support than just about anything else. To call these predictions "hypothetical" is absurd. These are predictions of a well established theory.

Actually general relativity is a good interpretation of the workings of gravity on the macroscopic scale but it falls apart at the small scale and is generally considered to be incomplete. It is currently expected that the theory will be deprecated by another more complete theory. As for quantum mechanics, the interpretation issue is important here. If a derivative of the many worlds interpretation is true, there are multiple realities and/or time lines. If a derivative of the Copenhagen interpretation is true, there are no alternate realities/time lines.

Quantum mechanics does seem to demonstrate that information can be sent backwards through time. The double slit experiment is a good example of particle-wave duality. Two slits are cut in a screen. The slits are side-by-side but separated by a strip of screen. Another complete screen is placed a distance behind the first screen. If a particle is sent towards the screen, it can only pass through one slit and will only strike the second screen in one place. A wave will pass through both slits and cause an interference pattern on the second screen. When a photon, electron, proton, nucleus, atom etc are launched at the slits, they behave as waves if they are not observed and as particles if observed. This observation can happen before or after the slits but if they are observed there is only one impact site. This means that the particle was a particle when traveling through the slits and only passed through one slit. The particle 'knew' that in the future it would be observed and so always acted like a particle throughout its life-span. This indicates that the particle passed information of its future encounters backwards through time. From the moment the particle was launched, its future path and all its future interactions were 'known'. Also remember that all quantum mechanical outcomes are probabilistically determined. It's just that somehow the random outcome of all these events is 'known' beforehand by the particles involved.

Also in Feynman diagrams, an anti-particle can be thought of as a regular particle traveling backwards through time.

[peragrin]

Going back to the point of the topic.

if you throw Goa'uld stargate into the ocean so they can't use it(stupid by the way as goa'uld can swim and stargates are very heavy) you run into another problem.

Goa'uld kick started human civiliazation bringing together nomadic tribes and teaching them farming techniques. (Remember in Stargate the goa'uld ruled earth for 5,000 years as the egyptian civilazation).Without which we may not be here today, as our society while based off more of Roman and greek styles, Romans and greeks were based off of Egyptian styles.

Even if you can change the past, you can't make even minor changes without seriously altering the timeline. Changes like. Kill off hitler in 1930, watch Stalin build the H bomb with ICBM before us. As stalin incorporates the very german scientists that we did.

Changing the past is very very stupid. you basically get a 1/1,000,000,000,000 shot in doing something that actually has a positive outcome.

[K^2]

If the Metaverse exists, then it calculates every possible future outcome.
if the Multiverse exists, it calculates the outcome of all physics settings.

those two combined would mean that the Ultraverse, so to speak, the multimetaverse, would be calculating every possible outcome of everything.

You're a bit off on this, but it sort of works like this. That's the principal behind the quantum computer. You split the load between superimposed states, each working as an independent computer with its own data set.

Universe doesn't exactly compute anything, though. It is a solution of an equation. You can re-write certain parts of that equation to correspond to the equation you need to solve, and then a certain process in nature is your solution. But if you think about it, this is how a regular computer works as well.

Actually general relativity is a good interpretation of the workings of gravity on the macroscopic scale but it falls apart at the small scale and is generally considered to be incomplete.

Yes, the GR model isn't designed to work on the scales on which Quantum Mechanics takes over, but we aren't talking about what happens to time on Plank's scale. We are talking about time travel. If we assume that time travel is achieved via a wormhole, General Relativity presents us with a complete solution. That solution does not allow present to be altered by sending something back through time.

It is currently expected that the theory will be deprecated by another more complete theory.

Which will converge to General Relativity under the limit of time scales much greater than Plank's time and energy scales much lower than Plank's energy. Same as Special Relativity converges to Galilean Relativity under the limit of speed of shifted frame being much smaller than speed of light. Same as Newton's Laws work within that setting, we expect General Relativity to work if we don't cross that Plank's energy scales, and there is no requirement to do so to achieve time travel, so no new predictions concerning time travel will be made by the new theory.

As for quantum mechanics, the interpretation issue is important here. If a derivative of the many worlds interpretation is true, there are multiple realities and/or time lines. If a derivative of the Copenhagen interpretation is true, there are no alternate realities/time lines.

You are mistaken. Many-World and Copenhagen interpretations are equivalent. No experiment can be performed to tell them apart, and there is a good reason for that. They are just different ways of looking at the same picture. Copenhagen interpretation describes outcome of a measurement as seen by a single observer. Many-World describes the world from perspective of all possible observers.

Collapse itself results in EPR paradox as well as certain issues with the entropy and makes the entire model non-linear. All of these are not problems if you keep in mind that we are looking at only one part of the whole picture.

More importantly, even if you want to be stubborn about it, the fact that the two are equivalent means that any prediction made in one holds in another, though, it might be a bit more difficult to see it one way than the other. If Many-World predicts multiple histories, they hold in Copenhagen as well, despite not being as obvious. In short, if Quantum Mechanics works, then we have multiple histories. Interpretation is just that, an interpretation.

Quantum mechanics does seem to demonstrate that information can be sent backwards through time.

Not by itself, no. Quantum Mechanics does not deal with information. Statistical Mechanics does.

The double slit experiment is a good example of particle-wave duality.

...

The particle 'knew' that in the future it would be observed and so always acted like a particle throughout its life-span. This indicates that the particle passed information of its future encounters backwards through time.

No, it absolutely does not. And I cannot stress this enough.

What you are describing is the result of entanglement between particle's state and detector's state. And the 'knowing' which path to take is actually a convoluted way of presenting Einstein-Podolsky-Rosen Paradox. It can be demonstrated that entanglement does not transfer information, therefore, preventing such causality violations.

This is another reason why I prefer Many-World interpretation. It'd be hard to invent such nonsense if you look at double slit from perspective of many world. Particle is in super-position of two states, one passing through one slit, the other through other slit. Now, you can chose to entangle yourself with the particles, by using detectors, or not. If you chose not to entangle, then you see interfering patterns. If you chose to entangle, then you yourself go into a superposition of two states. One only interacts with particle going through left slit, the other only with the one going through the right slit. This means that from your perspective, particle only took one path, and there is no interference.

Same exact argument, that no information is sent back, can be made using Copenhagen interpretation as the base. However, the argument would be about two pages long. Or so I'm guessing based on the argument about EPR, and as I said, this is very similar.

Also in Feynman diagrams, an anti-particle can be thought of as a regular particle traveling backwards through time.

"Thought of" is the key here. While the phase of the particle really does evolve as if the particle is running backwards through time, the information about interaction still travels forward.

This is why I am saying that time travel is a bit more complex than all that. Simplest model for time travel involves at least the framework of Special Relativity, a lot of Quantum Mechanics, and rather advanced Statistical Mechanics.

All of the key components for time travel have been developed and experimentally performed. We can work with entanglement to the point where we can now teleport quantum states. We can manipulate dynamics of small spin systems. We have performed localized time reversal. All that's left is using all that to piggy-back some information in the reversed system, and you'd have a system capable of sending things back through time. Though, right now, we are probably talking about something in range of 0.1-1 second. But we have not been able to do even that yet, because the Devil is in the detail, and time flow is an extremely persistent thing.

[clauz89]

We have models with very definite predictions about time travel, down to at least two distinct methods of "How-to". Both the General Relativity and Quantum Mechanics have been verified to an incredible degree. They are full fledged theories with better experimental support than just about anything else. To call these predictions "hypothetical" is absurd. These are predictions of a well established theory.
.

verified???
a theory can not be verified, only falsified...

[thekillman]

ofcourse it can be

[K^2]

verified???
a theory can not be verified, only falsified...

Look, I can say that the theory has sufficient experimental support to make it statistically unlikely that it would make wrongful predictions whenever a certain set of conditions is met. For example, F=ma is going to work provided that the mass and accelerations are sufficiently small.

That's what people usually mean when they say that a theory is verified, primarily, because that's is a lot shorter, and you can usually tell from context that this is implied.

From a strictly logical sense, nothing about reality can be proved or disproved. Any proof requires a set of axioms to start with, and there is absolutely no way to tell if the axiom set you chose has anything to do with reality.