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a reply to: delbertlarson

Okay, thank you, to reword it one more time,

So are you actually gaining mass when you gain speed?
Acceleration I believe is where the problem comes it, when it comes to getting there right?

As you go faster, it takes more force to accelerate less than before?

originally posted by: Mordekaiser
a reply to: delbertlarson

Okay, thank you, to reword it one more time,

So are you actually gaining mass when you gain speed?

No.

Acceleration I believe is where the problem comes it, when it comes to getting there right?

Yes.

As you go faster, it takes more force to accelerate less than before?

Yes.

Mass does not increase; momentum does. Also F = dp/dt, where p is the momentum; p = gamma*m*v. If we try to push on your space ship to make it go faster, and we watch from where you started we would see that F = dp/dt = d(gamma*m*v)/dt = gamma^3*m*a. The mass, m, stays the same, but gamma becomes increasingly larger as v approaches c. Were v to equal c, gamma would become infinite, so gamma just keeps getting so large that you can't ever get all the way to c.

FYI, the derivation of F = gamma^3*m*v is:
F = (d/dt)[(1-v^2/c^2)^(-0.5)]mv = -.5*gamma^3*(-2v/c^2)a*m*v + gamma*m*a
= gamma*m*a[(gamma^2*v^2/c^2)+1].
Now gamma^2 = 1/(1-v^2/c^2), so F = gamma*m*a*[(v^2/c^2)/(1-v^2/c^2)+1]
and rewriting 1 as 1 = (1-v^2/c^2)/(1-v^2/c^2) this becomes
F = gamma*m*a*[(v^2/c^2)/(1-v^2/c^2)+(1-v^2/c^2)/(1-v^2/c^2)]
= gamma*m*a*[1/(1-v^2/c^2)] = gamma^3*m*a.

originally posted by: Mordekaiser
As you go faster, it takes more force to accelerate less than before?

Yes it takes more and more force to accelerate as you go faster, but this isn't because mass is increasing as some old textbooks explain. Most modern textbooks no longer explain the reason it takes more force to accelerate is because of mass increase, but rather it's because of an increase in momentum and energy distorts space-time, so in this view it is space-time that is changing, not the internal properties of the object, as explained by textbook authors Taylor and Wheeler

"The concept of "relativistic mass" is subject to misunderstanding. That's why we don't use it. First, it applies the name mass - belonging to the magnitude of a 4-vector - to a very different concept, the time component of a 4-vector. Second, it makes increase of energy of an object with velocity or momentum appear to be connected with some change in internal structure of the object. In reality, the increase of energy with velocity originates not in the object but in the geometric properties of spacetime itself."

They are with the majority of textbook authors in not using the mass increase concept for relativity as of a survey done about a decade ago when 60% of textbook authors didn't use relativistic mass. That means only 40% used the concept then and it's probably less now as the idea is falling out of favor, but 40% was not zero so it was still being taught.

There was some controversy over the usefulness of the idea, but note that the author of the theory of relativity Albert Einstein said mass does NOT increase so he would have agreed with Taylor and Wheeler that teaching the idea of relativistic mass increase should be avoided. Obviously the 40% of authors who still taught the concept Einstein dismissed didn't agree with him (if they were aware he discouraged the idea), and thought the concept might provide some insights.

a reply to: Arbitrageur

So if the issue is spacetime, a shirk ray would be useful? Haha you answered my main question perfectly.

originally posted by: Mordekaiser
a reply to: Arbitrageur

So if the issue is spacetime, a shirk ray would be useful? Haha you answered my main question perfectly.

I don't know what a shirk ray is, but I can give you an example. Ever hear of the TV show space 1999 where the moon gets blasted into deep space? The concept in the TV show of an explosion doing that was completely implausible so let's say for our example that a race of advanced aliens have technology to accelerate toe moon to relativistic speeds, relative to earth.

From the perspective of an observer on earth, they watch the alien's power meter go higher and higher as it takes more energy to accelerate from 50% to 60% of light speed than it did to go from 40% to 50% of light speed, so from this perspective one might be forgiven for thinking the moon seems to be getting "heavier" or more massive as it becomes more resistant to acceleration.

But to show this is an effect of space time geometry and not mass increase, all one needs to do is have an observer on the moon (there was a moon base in the space 1999 TV show), and just stand on a bathroom scale to see if the moon is really getting more massive as it accelerates. An observer on the moon base won't see any change when they stand on a bathroom scale, even when the moon reaches velocities relative to earth where textbooks say the relativistic mass would be equal to rest mass so the total mass would be doubled. If it really was doubled, you would weigh twice as much, but there is no change to an observer on the moon standing on the bathroom scale, because from their space-time perspective, their velocity is zero, so why should they observe any mass increase? They don't, even though they are hurtling away from the Earth faster and faster and it's taking more and more energy to accelerate them.

So that's the idea behind saying it's space-time geometry, just look at the relativistic moon from two different perspectives in this example, and simply move your observer from the Earth to the moon and when on the moon the velocity of the moon seems to be zero to an observer there. Both observers' perspectives are equally valid and the mathematics of space-time allow us to translate between reference frames.

If for example we take a two "groups" of electrons, the electrons will randomly appearing and disappearing, but the size of these groups will always be constant.
Is it possible to store and instantly transfer information by this way?

a reply to: aim3333
To what experiment do you refer? Link to paper?

Particles can't "appearing and disappearing"[sic] without following strict conservation laws such as conservation of energy, conservation of linear momentum, conservation of angular momentum, and conservation of electric charge, so this places certain limits on how "random" such actions can be.

There is also the Heisenberg uncertainty principle which places limits on how precisely we can know a particle's position and momentum simultaneously, so this also raises the question, did the particle really disappear or did the experimenter just lose track of it for a time? If an electron traveling in a certain direction with certain momentum seems to disappear, and then another electron with the same momentum appears a short time later, how do we know the electron really disappeared and it's not a measurement issue? It's possible but this is why I ask for a reference to the experiment you're talking about to see if these details were examined. Maybe the experimenter knew the momentum so precisely that he just didn't know the position very well because that principle prevented such knowledge.

The only way to prove something is possible is to prove it's possible, so until someone does what you suggest all we can say is it's never been proven this can be done. In quantum teleportation there's a "no communication theorem" that meaningful information can't be instantly transferred, but it's just a theorem, not a proof. If someone proves meaningful information can be instantly transferred, that would invalidate the no communication theorem, but until that happens the best we can do is say it doesn't seem likely. We can't say whether it's possible or not with certainty.

By the way there's no problem sending random information instantly, equivalent to a string of random 1's and 0's that have no meaning and communicate nothing, that can be and has been done using quantum teleportation. We haven't been able to send any meaningful information instantly in any experiment so far, like a cookie recipe. The transfer of meaningful information has so far been limited to the speed of light.

a reply to: Arbitrageur

To the best of your knowledge has there been any work done on the compatibility of the mathematics of "warp drive" theory and those of the "Electro-gravitics" theory. If similarities can be found, it may help to bring reasonable space flight times a little closer into reality.

a reply to: tinymind
There is no theory of electro-gravitics. I can't find any reason to dispute this citation:

Electrogravitics

Byron Preiss in his 1985 book on the current science and future of the Solar System titled The Planets commented that electrogravitics development seemed to be "much ado about nothing, started by a bunch of engineers who didn't know enough physics". Preiss stated that electrogravitics, like exobiology, is "a science without a single specimen for study".

Now if you modify what you're asking about from "electrogravitics" to "ion wind", there are ion wind devices and theory behind their operation, but I wouldn't call that electrogravitics. I think in some people's confused minds there has been some confusion between the two.

The state of ion wind is not very impressive for commercial use since I have yet to see an ion wind device that can levitate its own power supply. However they make very impressive High School science fair projects. Here's a video showing how they work and a model of star Trek's enterprise with ion propulsion, as well as an ion lifter:

How Ion Propulsion, Lifters and Ionocrafts Work


The mathematics of warp drive technology is pretty interesting, problem is it requires exotic matter which is matter with negative mass. I don't know if that sounds hard to you, but to me it sounds hard to come up with negative mass and the most famous researcher working on warp drive technology admits that. We don't know how to do that and the technology hinges on that concept.

So bottom line, "electrogravitics" doesn't really exist based on all the research I know of so far. Ion lifters/propulsion do exist, and have been confused with electrogravitics, but have little in common with warp drive theory.

So, I've become quite engrossed in Brian Koberlein's blog, One Universe At A Time. He does a great job of bringing the details to a sufficient level while explaining them to the not-so-inclined individuals such as myself. In fact, he has provided the only explanation for the impossibility of FTL communication purely through QE that I've ever thoroughly grasped.
But he surprises me occasionally by seemingly contradicting himself with different posts. For instance, completely dismissing the existence of gravitons in one article, then explaining the theoretical model and treating them as a possibility in another.
While I still recommend his blog to science enthusiasts, I was wondering if anyone else had the same observations.
Also, has there been any new research that strengthens the argument for that particle recently? And what do you folks think of it's possibility?

Here's the home page:
briankoberlein.com

Anyone wanna explain in simple laymans terms the Fine Structure Constant.

a reply to: BASSPLYR

Aside from the fact that I can't tell if that's a sarcastic question or not, I wouldn't even pretend to know how to do that. Though, I've emailed Prof Koberlein with a couple of questions in the past and gotten surprisingly quick, friendly and helpful replies every time.
In the event of sarcasm, open bottle, fill glass, and sip.

a reply to: BASSPLYR

Though, as I seem to recall, you are much more well-versed in physics than myself. So if you get that answer, could you dumb it down a bit more and pass it along to me?

a reply to: Arbitrageur

Three possibly related questions:

1A - What is your opinion of the of "superfluid vacuum theory"?
1B - And if there is a "potential state" underlying what is a vacuum fluctuation?

2 - What is your opinion on the Higgs Boson, do you think it is, as speculated, the reason for asymmetry and mass?

a reply to: DefaultNamesake83

Just for my own reference, are you talking about matter-antimatter asymmetry regarding the Higgs?

originally posted by: BASSPLYR
Anyone wanna explain in simple laymans terms the Fine Structure Constant.

Along the same lines, I wonder if Wolfgang Pauli ever got an explanation from the devil. Of course he was a brilliant physicist so he wasn't looking for a layman's explanation:

www.bretthall.org...

(The fine structure constant), which has become ubiquitous in physics, remains mysterious. One of the pioneers of quantum theory, Wolfgang Pauli said of it, “When I die, my first question to the devil will be: What is the meaning of the fine structure constant?”. Michael Murphy writes that “All ‘everyday’ phenomena are gravitational and electromagnetic. Thus G and α are the most important constants for ‘everyday’ physics” (Murphy, 2007). As has been said, the fine structure constant is a measure of the strength of the electromagnetic force but it can also be regarded as a measure of how “relativistic” electrons in atoms are.

a reply to: DefaultNamesake83
My opinion doesn't differ from Renaud Parentani's:

If Spacetime Were a Superfluid, Would It Unify Physics—or Is the Theory All Wet?

Even supporters of the fluid spacetime idea say the concept is not very popular, and perhaps unlikely. But might it be true? “I have absolutely no idea,” says Renaud Parentani, a physicist at the University of Paris–Sud who originally suggested the idea of considering dissipation effects. “My frank opinion is that nobody has any idea. All we can do is model the various possibilities.”

I think we've ruled out space-time being a fluid, but so far a superfluid hasn't been ruled out to my knowledge.

a reply to: Arbitrageur

I haven't been on regularly in quite some time, but I noticed your new signature image. At least, it's new to me. That's wonderful. I love it.

a reply to: Arbitrageur

I guess were all in good company.

"All good theoretical physicists put this number (the fine structure constant) up on their wall and worry about it."
Richard Feynman

Ok, new question. It's about physics, but also about computer science.
With all the struggle to create stable qbits I keep reading about, is Google's DWave technology truly quantum computing? Or is it a quasi-quantum setup make to mimic the processing methodology of a truly quantum system?
Their newest system is supposed to begin testing sometime this year, and reportedly will harness 49 qbits in it's processor core. Are they really there? And if so, does anyone know the basics of the qbits themselves, and what the i/o system is for them?

a reply to: pfishy

Flux quantization might be an observational artifact due to grain anomaly. The publics knowledge of weak magnetic fields is very limited. Although the D wave technology may not yield the ultimate quantum effect processor the technology probably will offer some superposition advantages over sequential silicon processing. Of course even the early optical computers at Bletchley park did that..