Time Travel is Science Fiction

[paddoboy]

Hypothetical or not, theoretical or not, it doesn't really matter......
Again there's nothing in the laws of physics and/or GR that forbids it.

We also thought that a plane approaching the speed of sound would literally break up....and there were many killed in the scientific objective in attempting to overcome the many perceived problems that did exist at the speed of sound.
Now we take it for granted......

 

[dumbest man on earth]

Once again, origin, good Post. I hope you do not mind that I chose to present the supplemental information, but I though that possibly some of the Readers and Posters of SciForums (including yourself!) might just be interested in it.

The plazma state that may exist in BH jets, do nothing to invalidate the possibility of time travel of the twin paradox kind.....
The Alcubierre drive side steps that hypothetical problem.

So...paddoboy, you read and fully understood the .pdf at : http://arxiv.org/pdf/1311.5080v1.pdf , and you claim to be a Layman. Even most all journeyman physicists would not have picked up on that!

Congratulations just might be in the cards!

 

[paddoboy]

So...paddoboy, you read and fully understood the .pdf at : http://arxiv.org/pdf/1311.5080v1.pdf , and you claim to be a Layman. Even most all journeyman physicists would not have picked up on that!

Congratulations just might be in the cards!

Thank you......
No mention of time travel at all.........

Now go and have a word to the smart reputable people at NASA, JPL, Tau Zero, 100 Year Star ship company.....

And remember who the real nice bloke it was that informed you that NEITHER THE LAWS OF PHYSICS AND/OR GR, FORBID TIME TRAVEL.....
And also the fact that HUMAN KIND, GIVEN TIME, MAY ACHIEVE ALL THAT IS ALLOWED BY THE LAWS OF PHYSICS AND/OR GR.

Thank you linesmen, thank you ball boys, and thank you dmoe.

 

[OnlyMe]

Except that is a hypothetical based on special relativity that is valid only in a locally flat spacetime. From here to there and back is anything but locally flat spacetime.., even if the real world were not added to the equations.

And until someone actually tests even the smallest part of that hypothetical acceleration, it remains based on currently unproven postulates... A priori assumptions we cannot at present confirm.

You are seriously underplaying the validity and applicability of SR here and overplaying the amount of uncertainty about it. We have satellites in orbit that have confirmed SR time dilation.

The intended point was not that SR does not contribute to what we observe or experience, it was that the hypothetical does not account for anything other than SR, in its conclusions. Further the hypothetical is based on conditions that cannot be duplicated in reality. At least at present we are limited to conducting any experiments involving time dilation within a gravity well where GR time dilation exists. To take it a step further, and more to the point, the hypothetical, even were one to attempt to include the conditions added by GR, does not even consider any potential quantum mechanical effects.

But the other side of the coin; Duclan_Lunny's position that such acceleration can't happen has no support of any kind and is in fact against what the laws of physics tell us.

Look once more at the link Paddoboy offered. The conclusions are not the result of direct measurement. They are the result of interpretations based on theory and a priori assumptions... And the conclusions remain a theoretical interpretation. This is not an attempt to assert that they are not an accurate explanation of what is happening with the jets. I continue only to attempt to point out the difference between what we know as a result of experiment and experience and what we believe as the product of a theoretical interpretation of observations.

We have direct evidence of ions with relativistic velocities, both in the lab (LHC etc.) and detected as cosmic rays... We have no similar direct measurement, of whole atoms moving at relativistic velocities. Direct experimental evidence and measurements support Declan's assertion re: the ionization of matter at relativistic velocities. This is also consistent with at least some interpretations of the laws of QM.

From what we know based on direct evidence, an atom will be ionized at relativistic, even near relativistic velocities. We know this from laboratory based experiments, like those conducted at the LHC. If we accept that both, atoms in the jets mentioned are moving at relativistic velocities and that our experience locally with the ionization of atoms accelerated to relativistic velocities, we must also consider that "inertial" does not have a universally consistent definition... Or perhaps there are other conditions at play that are not currently being considered or perhaps even understood.

 

[dumbest man on earth]

Thank you......
No mention of time travel at all.........

Now go and have a word to the smart reputable people at NASA, JPL, Tau Zero, 100 Year Star ship company.....

And remember who the real nice bloke it was that informed you that NEITHER THE LAWS OF PHYSICS AND/OR GR, FORBID TIME TRAVEL.....
And also the fact that HUMAN KIND, GIVEN TIME, MAY ACHIEVE ALL THAT IS ALLOWED BY THE LAWS OF PHYSICS AND/OR GR.

Thank you linesmen, thank you ball boys, and thank you dmoe.

Time Travel is Science Fiction - that is the Title of this Thread!

Delusions of grandeur is certainly rife around here.

You seem to be absolutely correct about that, paddoboy! Incidentally, you are the only Poster occupying your geographically located "here" - in that that "here" is the "physical biological entity" in existence between your chair and your keyboard.
So...I can do nothing but concur, 100%, to your clearly worded seemingly self-satisfying and convincing proclamation that Delusions of grandeur are certainly rife around there!

Like I said, delusions of grandeur.....[but understandable as forums are the only outlet they have]

Again, paddoboy, I must concur 100%! Forums do seem to be the only outlets that you seem to have for your self-proclaimed delusions of grandeur...!

So you need to be careful when discussing an Idea or claiming a new model, better then any incumbent model....You understand?

Time Travel is Science Fiction in reality - ideas and models are just ideas and models - they are not reality.

Wrong. It is a legitimate theoretical prediction of relativity.

Once again, I 100% concur that Time Travel is a legitimate theoretical prediction of relativity. However, the Title of this thread is : Time Travel is Science Fiction and NOT : Time Travel is a Theoretical Impossibility.

Rubbish...The ship is stationary and moves with the bubble.
I think you need to familiarise yourself with the Alcubierre drive....
There possibly may be other problems, including energy requirements, but it is a logical accepted theoretical concept.

Indeed, paddoboy, I concur 100% that it may very well be that Time Travel is a logical(ly) accepted theoretical concept. It is still, however illogical to accept it as a Physical Reality.

There articles that simply show FTL is theoretically possible as I have described...let's say a "perceptionof FTL"

I 100% concur. The articles do not show that it is in any way possible in reality, though.

No, I have not.
The point of this thread is time travel being theoretically possible [as per the twin paradox]
And I have shown that, as have others.

On this I must 100% Not concur! The "point of this thread" - as per the Title in the OP is : Time Travel is Science Fiction.

Which means that time travel [as per the twin paradox] is theoretically conceivable.

Yes...back to concurrence - Time Travel could be said to be "theoretically conceivable" - but in this Physical Reality, Time Travel is Science Fiction.

BTW, paddoboy, I will include a partial listing of things that may be "theoretically conceivable", but are not manifest in actual Physical Reality :
Santa Clause...Unicorns...Fairies...Goblins...the Klingon Cloaking Device...The renowned Terran American scientist and developer of warp drive, Zefram Cochrane...the ability of some Posters on SciForums to be Truly Open Minded...the ability of some Posters on SciForums to be capable of fully understanding the difference between actual reality and Theoretical Constructs...

 

[origin]

From what we know based on direct evidence, an atom will be ionized at relativistic, even near relativistic velocities.

No actually we don't know that.

We know this from laboratory based experiments, like those conducted at the LHC.

Nope that is not evidence that atoms cannot exist at relativistic speeds.

If we accept that both, atoms in the jets mentioned are moving at relativistic velocities and that our experience locally with the ionization of atoms accelerated to relativistic velocities,

Now this is accurate. If charged particles experience acceleration of 0 to close to light speed in seconds the forces on them can literally tear atoms apart.

we must also consider that "inertial" does not have a universally consistent definition... Or perhaps there are other conditions at play that are not currently being considered or perhaps even understood.

The conclusions that you have drawn from the experiments, that it is the velocity and not the acceleration that puts forces on the atoms, is very strange to say the least.

The other obvious point that you seem to be missing is that we can ONLY accelerate charged particles, not neutral atoms, so the fact that we only see relativistic ions in LHC is sort of a weak argument, don't you think?

 

[paddoboy]

Time Travel is Science Fiction - that is the Title of this Thread!

[/B]

Really dmoe, your inferences are wrong and the thread title was nothing more then a red herring by Farsight due to the belting he was receiving elsewhere.
Remember today's science fiction is tomorrow's science fact, and the theoretical possibility of it is not forbidden by the laws of physics and/or GR.

The rest of your post is as usual, although I should thank you in some respect.
I mean Imitation is the greatest form of flattery...so once again, thanks.

 

[OnlyMe]

From what we know based on direct evidence, an atom will be ionized at relativistic, even near relativistic velocities.

No actually we don't know that.

Point taken,

I should have phrased that as, "an atom accelerated to near relativistic velocities", but then acceleration is involved in all of both our local experimental experience and even the jets associated with the paper, Baryons in the relativistic jets of the stellar-mass black hole candidate 4U1630-47 at, http://arxiv.org/abs/1311.5080. I assumed acceleration was implied...

We know this from laboratory based experiments, like those conducted at the LHC.

Nope that is not evidence that atoms cannot exist at relativistic speeds.

You are correct. It is not evidence that atoms cannot exist at relativistic velocities.., but then neither is it evidence that they can. On the face of it it does support the assertion that at least the referenced experimental evidence supports the conclusion.

Origin, with the exception of the implications associated with an accelerating expansion of the universe, we do not see any large mass moving relative to us at anything but classical velocities. And the jets being discussed originate from within the context of the inertial environment of what is assumed to be a black hole... So those jets had to have experienced acceleration. The fact that similar jets seem to die out or slow down or fade away at great distances suggests that any initial acceleration also degrades or slows as they move way from their point of origin. Which again suggests an initial rapid acceleration followed by a constant deceleration, the mechanism of which is yet to be explained or understood.

If we accept that both, atoms in the jets mentioned are moving at relativistic velocities and that our experience locally with the ionization of atoms accelerated to relativistic velocities,

Now this is accurate. If charged particles experience acceleration of 0 to close to light speed in seconds the forces on them can literally tear atoms apart.

As above, all of the observational evidence we have suggests that any acceleration, or velocity associated with the material, ionized or not, within the kind of jets described, does slow down as the jets move away from their point of origin. There is nothing in the data at this time that suggests that the jets have a uniform velocity over their whole length. And if there were it would suggest an almost instantaneous initial acceleration.

we must also consider that "inertial" does not have a universally consistent definition... Or perhaps there are other conditions at play that are not currently being considered or perhaps even understood.

The conclusions that you have drawn from the experiments, that it is the velocity and not the acceleration that puts forces on the atoms, is very strange to say the least.

As mentioned above, anywhere we observe relativistic velocities experimentally or as a theoretical interpretation of observations, accelerations are implied. Even light moving at c has a point of origin that is essentially inertial relative to the photon. Again any relativistic velocity implied past acceleration.

The other obvious point that you seem to be missing is that we can ONLY accelerate charged particles, not neutral atoms, so the fact that we only see relativistic ions in LHC is sort of a weak argument, don't you think?

This is not quite true. There are atoms that can and have been suspended in a magnetic bottle. Those same atoms could be accelerated by the same mechanisms used in almost any particle accelerator. However you don't see whole atoms accelerated to relativistic velocities.

Just because experiments in particle accelerators focus on ions, does not mean that all atoms cannot be accelerated in a similar manner.

 

[origin]

Point taken,

I should have phrased that as, "an atom accelerated to near relativistic velocities", but then acceleration is involved in all of both our local experimental experience and even the jets associated with the paper, Baryons in the relativistic jets of the stellar-mass black hole candidate 4U1630-47 at, http://arxiv.org/abs/1311.5080. I assumed acceleration was implied....

I don't disagree with anything in your post. But my whole point was if you accelerate at 1g to relativistic speeds there is no reason to think it would have any negative affect on an atom or a person.

Now that being said there is the small problem(!!) of harnessing enough power to accelerate at 1g for a year, as the resistence to inertia is increasing to boot. And other minor problems like hitting atoms and electrons in flight, which due to the relative velocities would cause them to become ionizing radiation.

 

[OnlyMe]

I don't disagree with anything in your post. But my whole point was if you accelerate at 1g to relativistic speeds there is no reason to think it would have any negative affect on an atom or a person.

If you limt the discussion to SR and GR then you are correct.

That said the world is now much larger than the two combined.

Just add to the conceptual model the EM spectrum of the zero-point field, which while locally observed to be isotopic, originates, with the electromagnetic characteristics of matter throughout the universe. The fact that we know through things like the Casimir effect that matter and the ZPF interact, suggests that there is or maybe forces at play when relativistic velocities are involved.

A single reference is difficult, but some of the work done by Puthoff, Rueda, Hairsch et. al., re: inertia as emergent from the interaction of an accelerated charged particle with the ZPF, might open the door.

 

[Farsight]

Sorry to have been away for a while guys. I was ill for a day or two then I had to focus on some work.

I'll read back a few pages and try to catch up.

 

[Farsight]

Time travel is impossible. Forget GR and twins for a moment. You have to work with ALL the rules of physics. The physics of thermodynamics, materials, etc, etc, Do you have any idea of what happens to matter when it reaches relativistic speeds? At the point when it's kinetic energy surpasses it's rest mass energy, it no longer is treated as matter, it has the properties of radiation. (And that's just at the particle level, when you try to keep a spaceship or person intact at relativist speeds, they fall apart.) You and your spaceship will become a ball of plasma long before you reach relativistic speeds.

You would be better pursuing cryo-stasis if you want to see what things are like in 225 years. That's at least a possible thing.. Spaceships, machines and people at relativistic speeds is GR woo, but there are other physics you aren't accounting for.

Good stuff Declan. Maybe though the kinetic energy surpasses rest mass thing applies more to a falling body?

 

[Farsight]

@ paddoboy,,

You act exactly like those anti-mainstream people you rail against. They also refuse to accept well established science when it goes contrary to their "pet project". And also like them, you latch on to a few phrases and repeat them ad nausium because you don't understand the underlying principles. Time travel is not possible for us. Physics precludes it.

1) Twin paradox is not a GR paradox. It is a misunderstanding of the General Theory of Relativity. BUT IT IS A TRUE PARADOX. One of the first postulates of GR & SR is that the laws of physics MUST operate the same for all the Universe, there is your paradox..

2) In making physics fun for the lay public, the popularizations of physics ALWAYS introduce the woo science as being "allowed". That is the disservice they do to the lay public in general, and seems to have done to you in particular.

3) GR IS well tested and experimentally verified science. But it does not allow you to dispense with other areas of physics that are just as well tested or even more strictly verified, i.e. Quantum Field Theory, Particle Physics, Thermodynamics, Bio-Chemical Physics. GR allows your "twin paradox", but those other equally valid fields DISALLOW it. That first postulate of GR does not allow you turn off physics for your special "twin's" reference frame.

4) What happens to a single atom at relativistic speeds? It CAN NOT exist as an atom. Much less an entire complex system of atoms (as in a complicated spaceship or a biological system of atoms like a "twin").

5) NASA, JPL, and all the others continually sponsor "woo science". Not because they are seeking the "fun" answers you are so enamored with. Because individuals do these as a means of testing the limits of models and methods of modeling. They don't invest money on these things, they lend their "name" to them only. Those people earn their pay by doing real science and NASA allows them to attach it's name to their pet "fun" projects.

6) NASA, JPL, el. al have also lent their name to people investigating Aether models, MOND models, TeVeSc Models,,,, people associated with NASA have been proponents of Plasma Cosmology, Electric Universe Cosmology, Steady State Cosmology, and contracting universe cosmology. One prominent former NASA guy thinks quasars and pulsars are alien communication networks. There is no shortage of "woo" scientists at NASA or anywhere else in the mainstream.

7) As an apologist for the mainstream, you should slack up and give it a rest for awhile. Because you repeat the same banalities and inanities over and over and over. That will turn people off of your "message" because they will begin to think that you can't think for yourself and can only parrot a few restricted phrases. I'm as mainstream as you will ever find anywhere. I'm professionally employed doing mainstream science and have been for a decade. I'm also embarrassed by your rather superficial defense of what is mainstream and what is not.

8) Time travel by means of relativistic speeding is not mainstream. Particle physics (as well or better tested than GR) doesn't permit it. Quantum Field Theory (as well or better tested than GR) does not permit it. Bio-chemo-physiology (very well tested) does not permit it. Nuclear physics (as well or better tested than GR) does not permit it.

9) GR does NOT permit it either, because GR says physics must operate by the same rules for everyone, including the rules of QFT, Particle Physics, Nuclear Physics, etc, etc,,,,

Until "time travel" is compatible with ALL physics, it's science fiction pure and simple.

Love it.

 

[Waiter_2001]

One cannot "go back" in time but what about OVERTAKING time? Travelling faster than time. Would one then go back into the past?

 

[Farsight]

No. Read the OP. Time doesn't flow, or pass. Things move, sh*t happens, that's it.

 

[dumbest man on earth]

One cannot "go back" in time but what about OVERTAKING time? Travelling faster than time. Would one then go back into the past?

Waiter_2001, how "fast(?!)" does "time travel(?!)"?
How "fast(?!)" would someone have to "travel(?!)" to effectively succeed in "OVERTAKING time(?!)"?

 

[paddoboy]

One cannot "go back" in time but what about OVERTAKING time? Travelling faster than time. Would one then go back into the past?

In a way that is what happens in the twin paradox.
From the stay at home twin's perspective, his rate of time passing is faster [overall] then the travelling twin.
The equivalence principal is disrupted by the acceleration and deceleration phase of the travelling twin.
The changes in the flow rate of time, becomes quite obvious when the travelling twin returns and they are reunited.

The same situation happens everyday with our astronauts on the ISS, and even plane travel, but the effects at those sub relativistic scenarios are not so obvious.
For the travelling twin, this is future time travel.......theoretically possible.
Time travel into the past is another matter, and not so straight forward....
But maybe one day in the distant future, when we have the technology and knowhow, we just maybe able to warp space time at our will and maybe even create wormholes.
These could give us a means to travel into the past......
But what of the GranDaddy paradox I here someone ask?
Due to the real nature of time as being flexible, that would not create any problem.
One would simply create another timeline, with different results in history.
I think Feynman's "Sum Over History's " attests to that.

Either way, as I mentioned in my previous post, the thread title is a misnomer, and was just a red herring after one of our few posters that suffers from delusions of grandeur, decided to rewrite SR/GR
Many many things we take so much for granted today, were all science fiction yesterday.
That is an undeniable fact.

 

[paddoboy]

Once again, I 100% concur that Time Travel is a legitimate theoretical prediction of relativity. However, the Title of this thread is : Time Travel is Science Fiction and NOT : Time Travel is a Theoretical Impossibility.

Really dmoe, your seemingly over the top at attempting to be attentive to detail, is leading to your utter confusion.
Again, today's Sci/Fiction, can be tomorrows Sci/Fact.
And since we both agree it is theoretically possible, it's nice to see that supported by the fact that the laws of physics and GR do not forbid it.

Indeed, paddoboy, I concur 100% that it may very well be that Time Travel is a logical(ly) accepted theoretical concept. It is still, however illogical to accept it as a Physical Reality.

You are trying to hard with your obsession for supposed detail and confusing your self.
In fact it is a physical reality with inert concepts such as particle accelerators, projected lifetimes of particles such as Muons and even GPS.
It certainly is not a physical reality with real live humans as yet. Did anyone ever say it was?
But nothing forbids that happening in the future, which will then make it a physical reality.
You obviously agree with that. Good.

So, in summing we all must conclude that [1] Time travel although science fiction at this time, does not mean it is impossible, as per the obvious message that Farsight was presenting after copping a pounding in the other thread where he attempts to rewrite relativity.
[2] It is not forbidden by any know law.......[3]What we see today as science fiction, does not mean it will always be science fiction. [4] It does happen now in limited and inert scenarios such as particle accelerators etc [5] It will be very difficult to achieve with humans, as will relativistic speeds, and obtaining and controlling energy requirements to warp space/time ect as per the Alcubierre drive...

Nothing is achievable by looking at time travel and associated endeavours pessimistically.....Pessimism has achieved nothing for the human race.
We need enthusiasm, Innovation, and optimism which thankfully is being undertaken as we speak.
It ain't gonna be easy, but nothing worthwhile is ever easy.

Given time, we can achieve all that is allowable by the laws of physics and GR.


.

 

[dumbest man on earth]

In a way that is what happens in the twin paradox.
From the stay at home twin's perspective, his rate of time passing is faster [overall] then the travelling twin.
The equivalence principal is disrupted by the acceleration and deceleration phase of the travelling twin.
The changes in the flow rate of time, becomes quite obvious when the travelling twin returns and they are reunited.

In Post #51 of this Thread, you described "the Twin Paradox" thusly :

An example of possible time travel is as follows.....
One person of a set of twins decides to take off on his/her relativistic space ship and travels at 99.999%c for six months, before making a U turn and returning back to Earth at exactly the same 99.999%c.
He returns obviously 12 months older and with all onboard clocks showing that 12 months have passed.
But surprise!!!. When he lands and alights from his ship, he finds his sibling twin long dead and buried and an Earth 225 years later.
[For the sake of simplicity acceleration and deceleration phases have been ignored]

paddoboy, there seems to be some inconsistencies or a misunderstanding on your part of "the Twin Paradox"!

1.) - in your Post #51, you seemed to state that when the "traveling twin" returned to Earth, that it was 225 years later - which would seem to indicate that his "stay at home twin" would have probably been dead for quite a while - which would in turn seem to rule out the possibility of the "twins" being "reunited".

2.) - from the "stay at home twin's perspective" 225 years pases at the normal rate, thus taking 225 years for his clock to tick off 225 years.
yet from the "traveling twin's" perspective 225 years passed while his clock only ticked off 12 months.

3.) - SAHTwin - perceiving/experiencing 225 years = actual 225 years = normal rate of time.

TTwin - perceiving/experiencing 12 months = actual 225 years = 225 x normal rate of time.

???!!! - This would seem to indicate that the rate of time passing is faster [overall] (in your example), on the "traveling twin"!

paddoboy, since I do not believe in "Time Travel", nor do I believe that any "traveling twin" has ever decided to "take off on his/her relativistic space ship and travel at 99.999%c for six months, before making a U turn and returning back to Earth at exactly the same 99.999%c" to test your example or hypothesis or theory - I can not be the person that is providing the inconsistencies or misunderstanding of "the Twin Paradox"!

paddoboy, would you please clarify or explain?

 

[Beaconator]

Now that being said there is the small problem(!!) of harnessing enough power to accelerate at 1g for a year, as the resistence to inertia is increasing to boot. And other minor problems like hitting atoms and electrons in flight, which due to the relative velocities would cause them to become ionizing radiation.

If the resistance to inertia is increasing wouldn't it be easier to accelerate?