Light speed

Oct 10, 2011 By Steve Nerlich, Universe Today
You could cross the universe in a matter of hours without ever 'breaking light speed' - it is not the speed limit that it seems to be.

The recent news of neutrinos moving faster than light might have got everyone thinking about warp drive and all that, but really there is no need to imagine something that can move faster than 300,000 kilometres a second. Indeed, the whole idea is illogical.

Light speed, or 300,000 kilometers a second, might seem like a speed limit, but this is just an example of 3 + 1 thinking – where we still haven’t got our heads around the concept of four dimensional space-time and hence we think in terms of space having three dimensions and think of time as something different.

For example, while it seems to us that it takes a beam 4.3 years to go from Earth to the Alpha Centauri system, if you were to hop on a spacecraft going at 99.999 per cent of the speed of light you would get there in a matter of days, hours or even minutes – depending on just how many .99s you add on to that proportion of .

This is because, as you keep pumping the accelerator of your imaginary star drive system, time dilation will become increasingly more pronounced and you will keep getting to your destination that much quicker. With enough .999s you could cross the universe within your lifetime – even though someone you left behind would still only see you moving away at a tiny bit less than 300,000 kilometres a second. So, what might seem like a speed limit at first glance isn’t really a limit at all.

To try and comprehend the four dimensional perspective on this, consider that it’s impossible to move across any distance without also moving through time. For example, walking a kilometer may be a duration of thirty minutes – but if you run, it might only take fifteen minutes.

The effect of time dilation is negligible for common speeds we are familiar with on Earth, but it increases dramatically and asymptotically as you approach the speed of light.

Speed is just a measure of how long it takes you reach a distant point. Relativity physics lets you pick any destination you like in the universe – and with the right technology you can reduce your to that destination to any extent you like – as long as your travel time stays above zero.

That is the only limit the universe really imposes on us – and it’s as much about logic and causality as it is about physics. You can travel through space-time in various ways to reduce your travel time between points A and B – and you can do this up until you almost move between those points instantaneously. But you can’t do it faster than instantaneously because you would arrive at B before you had even left A.

If you could do that, it would create impossible causality problems – for example you might decide not to depart from point A, even though you’d already reached point B. The idea is both illogical and a breach of the laws of thermodynamics, since the universe would suddenly contain two of you – the other you having appeared out of nowhere.

So, you can’t move faster than light – not because of anything special about light, but because you can’t move faster than instantaneously between distant points. Light essentially does move instantaneously, as does gravity and perhaps other phenomena that we are yet to discover – but we should never expect to discover anything that moves faster than instantaneously, as the idea makes no sense.

We mass-laden beings experience duration when moving between distant points – and so we are able to also measure how long it takes an instantaneous signal to move between distant points, even though we could never hope to attain such a state of motion ourselves.

We are stuck on the idea that 300,000 kilometres a second is a speed limit, because we intuitively believe that time runs at a constant universal rate. However, we have proven in many different experimental tests that time clearly does not run at a constant rate between different frames of reference. So with the right technology, you can sit in your star-drive spacecraft and make a quick cup of tea while eons pass by outside. It’s not about speed, it’s about reducing your personal travel time between two distant points. And that has a natural limit – of zero.

As Woody Allen once said: Time is nature’s way of keeping everything from happening at once. Space-time is nature’s way of keeping everything from happening in the same place at once.

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User comments : 89

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Noumenal
4.1 / 5 (14) Oct 10, 2011
I think the problem isn't the getting there: It's the time that changes in the reference frame of a human being on earth that's the problem. Sure, you leave in your space-ship at 99.999999% the speed of light, and arrive 60 million light years away. For you it has been some weeks maybe, for the poor person on earth, it has been quite a lot longer..

What we want is to move from one point in space-time, to another point in space-time without leaving the 'normal' earth reference frame we are in. In this way we would be moving faster than the speed of light, as we arrive backwards in time, i.e., at the location we want to go without having to take the 'time', in this case a function of velocity, we ought to have taken to get there.
AtomThick
1.7 / 5 (6) Oct 10, 2011
Theoretically there is a way (from the Lorentz formula above). If the rest mass of neutrino is a complex number then it can have mass as a real number only if it travels at a speed grater than that of light. As we can only detect masses that are positive real numbers then we can only see it when it goes at this greater than light speed.
hard2grep
2.2 / 5 (9) Oct 10, 2011
Considering that the universe is expanding at an ever-faster rate, I think that you'd never get there... a trip that fades to nothing...
hard2grep
1.6 / 5 (5) Oct 10, 2011
I wonder if you just instantly evaporated as you stepped out into the ultra deep void. The universe would sure have a large amount of velocity of expansion by then; the speed of light, correct?
kochevnik
1.6 / 5 (12) Oct 10, 2011
Maxwell's equations have two components, one which travels forward in tome and the other is time-reversed. Antiparticles travel backward in time. Besides there are thousands of different logics. Causality varies depending upon the inertial frame of reference, which inspires the name "relativity." Even hippies know that. The laws of thermodynamics apply to closed systems only, yet nobody has yet successfully created a closed systsm because they are thought experiments. This article is fluff and smacks of being written in the 70s.

In physics I was told that c is a barrier. Nothing prohibits particles going faster or slower than it. Indeed phase waves do exactly that.

There is no time. Time is a consequence of the law of energy conservation.
hard2grep
1.5 / 5 (4) Oct 10, 2011
I wonder if the rate of impact probability exceeds the occupants. Remember that you are compressing your experience of an extremely long distance into an instant on your side--- (compression). every individual object velocity will be nothing in comparison and the radiation exposure-lethal...
Nanobanano
1.9 / 5 (9) Oct 10, 2011
So you're saying the "age" of distant objects is itself an illusion, because the time dilation of a photon causes "delta T" to be assymptotically close to zero. Which is to say, every photon's age in it's own reference frame is always zero.

As for paragraph 2 in the main body of this article, I thought this was obvious.

I said this and presented math showing it for anyone who did not realize it, and was given tons of negative feedback, and even censored and banned by the admins over it in the past.

But NOW because they will make money off an article written by someone who they give special authority to, now they have no reservations about posting it world wide themselves.

As for the passage of time outside the ship, I guess we just get over it if humans want to survive past the Earth...
Nanobanano
2.8 / 5 (12) Oct 10, 2011
Think about that.

If there were ancient aliens, or if humans destroyed themselves in the ancient past in a nuclear war (such as what the guys on "Ancient Aliens" claim,) then consider this.

If some of those humans had been on an "away mission" in a relativistic space craft, and then came back after their journy, what would they be?

From our perspective five, ten thousands of years would have passed, or more.

The UFO's everyone claims to see could just be ancient human explorers coming back home, only to find their respective ancestors destroyed themselves in the past.

I don't really believe that, but the equations suggest that is plausible.

They could have traveled thousands of light years distance and then studied a destination object, and came back, and from our histoy's perspective it would have taken maybe 10,000 years, but from their perspective, if they traveled fast enough, they might have been gone only a few days...
hard2grep
1 / 5 (3) Oct 10, 2011
Techniqaly speaking, if you could excite all the atoms equally at the same time (electromagnetic?) in one direction at relativistic (particle accelerator-like) speeds, the trip of an astronaut would be for as long as the machine is activated. imagine a ship that is meant to navigate through stellar material. its passengers frozen it time as the ship makes way for the next planet. Seems a bit of an energy hog, though. why not store it in a condensate. as the ship sets up port with an expanding structure, the engines timely pull from reverse to the generators. These ships would be like cities on islands of time because of the differences in distances. Need more shields Scotty.
jmlvu
1.6 / 5 (7) Oct 10, 2011
To a neutrino lifeform traveling at greater than the speed of light, I think causality breaks down. Events don't happen in the same order as they do for us sub light speed creatures.
jamey
2.5 / 5 (11) Oct 10, 2011
Ok - I've always had a problem with this BS about something not happening until you see the light from it.

Planets A and B are equidistant from Planet C, but on opposite sides. Planet C blows up - so the light from the explosion reaches A & B at the same time. People on Planet A then know that light from the explosion is *ALSO* reaching Planet B at the same time - and vice-versa. But with the BS the relativitists keep coming up with - they want to say the people on Planet A don't - and can't. Let's tell them to get stuffed. Everyone thought the equations describing a positive electron were just mathematical side-effects, until someone found one. Relativity allows for particles with imaginary rest masses - and everyone wants to say *THAT* is just a mathematical side-effect - but maybe we're actually detecting them for the first time?

(And really - neutrinos from a terran particle accel are more energetic than from a supernova? SERIOUSLY???)
Nanobanano
2.1 / 5 (9) Oct 10, 2011
Jamey:

Stuff doesn't make sense because people don't quite understand what physics really is.

Our "laws of physics" that are in a text book are not "really" the laws of physics at all.

They are very close approximations to the "real" laws of physics, which give accurate predictions for certain classes or sub-classes of phenomenon for which they were derived.

In some cases, it's true that a mathematical formula may predict something totally unexpected, such as tachyons, but you should not take that "literally" until you actually verify it.

The "Twin paradox" has never actually been tested. only a few experiments with gravitational time dilation and frame dragging. But literally getting in a ship and flying around at relativistic speed for 20 years has never been done, so nobody knows what the REAL outcome is. Only what some formula says "probably" happens, based on a thought experiment, or a few other experiments not quite the same...
hush1
1.5 / 5 (6) Oct 10, 2011
Its not about speed, its about reducing your personal travel time between two distant points. And that has a natural limit of zero. - Dave


The only way to separate two points is with spacetime?
The only way to merge two points is without spacetime?

In a frame of reference a collision occurs.
The collision never was in a different frame of reference?

but we should never expect to discover anything that moves faster than instantaneously, as the idea makes no sense.


"Sorry you feel the way, Dave", answered Nature.

"Find comfort in knowing that (with or without time) everything makes sense - when your name is Nature, not God."
hush1
1 / 5 (2) Oct 10, 2011
Steve Nierlich="Dave" above.
AWT
1 / 5 (7) Oct 10, 2011
In dense aether model the space-time (brane) can be modeled with density gradient at the phase interface of two elastic fluids. After then a two kinds of solitons will appear: A) the one, which corresponds to photons and it spreads with slightly lower speed, than the transverse surface waves (which are serving as an analogy of light waves) B) the faster one, which corresponds the neutrinos and it will spread with slightly higher speed, than the surface ripples. The first kind of solitons results from coupling of surface ripples with longitudinal bulk waves of more dense phase, the second one from coupling of surface ripples with longitudinal waves of less dense phase. From this perspective the neutrinos would behave like the superpartners of gamma ray photons, i.e. like the lightweight photinos. It means, the neutrinos aren't real tachyons and they can even move with subluminal speeds, being bound to space-time brane.
AWT
1 / 5 (9) Oct 10, 2011
In dense aether model the real tachyons manifest itself like the chaotic CMBR noise, similar to underwater sound waves. Such waves manifest like the Brownian noise at the water surface, coming from all directions at the same moment. IMO the gravitational waves are such a tachyons. As Eddington pointed out already before many years, gravitational waves do not have a unique speed of propagation. The speed of the alleged waves is coordinate dependent. A different set of coordinates yields a different speed of propagation and such waves would propagate like noise.
Pyle
3.8 / 5 (6) Oct 10, 2011
Time travel presents paradoxes. Traveling FTL doesn't. So what if you get somewhere faster than the light that left with you?

Special relativity gives us our speed limit for accelerating mass, but breaking causality is limited to time travel. As far as we know it is "now" everywhere. We won't hear anything from anywhere until the light reaches us from there, but travelling faster than c to get there wouldn't break causality.

To me the answer to FTL travel is to achieve the "velocity" without continuous acceleration. I dunno how that would be possible, but at the quantum level it appears to be, so maybe at the macro level there is a way. I'd say we need to start easy with FTL communication. Seems to me that getting massless stuff somewhere quick should be easier than handling the massive problem.
Edward_Emanuel
1 / 5 (4) Oct 10, 2011
You need higher capacity engine not solar or wind. You need higher energy. Like nucler and fusion.
Edward_Emanuel
1 / 5 (4) Oct 10, 2011
You need a bubble to go fast and slow down.
Pyle
4.5 / 5 (6) Oct 10, 2011
I always try to hit UniverseToday before I comment on Nerlich's articles. Don't know why I didn't today. Anyway. Everybody interested should check it out. I might not have fully understood it, but LC is awesome. (Nobody addressed my above comment there, but that is because it isn't real physics, just silly sci-fi nonsense.)

http://www.univer...t-speed/

btw, the best part of the UT board is Nerlich responds to comments there. (BLATANT HINT TO PHYSORG WRITERS)
hush1
2.6 / 5 (5) Oct 10, 2011
lol
I response with comments to articles not yet written. Sidestepping any apparent or real paradox involving time.

Of course my comments don't make sense - until the article is written. By that time everyone has forgotten my comments.
hush1
1 / 5 (2) Oct 10, 2011
Pyle
I like your comment no one responded to yet.
Anyway, I like Steve. Meticulous most of the time.
LariAnn
2.3 / 5 (7) Oct 10, 2011
Reference "time", I postulate that the fourth dimension is not what is conventionally referred to as "time". "Time", as conventionally understood, is a ratio, not a direct measurement. It is the ratio of one change over another change (example: distance a runner covers/distance the second hand covers on a stopwatch). These are two physical distance measurements which, when compared as a ratio, give rise to "time". But that is not a measurement along the fourth dimension - the real fourth dimension is a direction at right angles to all three spatial dimensions and, as such, is always at right angles to any direction of travel in space. So to 'travel in time", you have to travel at right angles to ALL of the spatial dimensions simultaneously. Unfortunately, doing so will transport you across different "timelines" (actually changelines) and you will no longer be in "your" time frame on arrival at your destination. (IMHO)
AWT
1.4 / 5 (9) Oct 10, 2011
You can travel in time, but you would collapse of explode during this, so it's not recommendable approach.
Vendicar_Decarian
0.6 / 5 (39) Oct 10, 2011
In QM, a particle exists everywhere at once with decreasing probability as the distance scale increases. Hence it is quite possible for the speed of light to be exceeded.

In QM, c is defined by the average time needed to move from a to b through all possible paths and through all possible interactions with matter and with the virtual sea of energy that comprises the vacuum between matter.

AWT
1 / 5 (4) Oct 10, 2011
Hence it is quite possible for the speed of light to be exceeded
It just prohibits to observe momentary state of wave function. The neutrinos are different. They violate speed of light, but just a little, so they remain observable in nearly deterministic way. This determinism is violated with neutrino oscillations in subtle way only. From this perspective the neutrinos don't violate the special relativity in strict sense, because their position and mass is not completely deterministic. Special relativity can be completely exact just for completely deterministic particles.
Pyle
2 / 5 (1) Oct 10, 2011
In QM, a particle exists everywhere at once with decreasing probability as the distance scale increases. Hence it is quite possible for the speed of light to be exceeded.

So, VD. Are you actually saying that it might be possible, if we had enough information to calculate the improbability of all our quantum particles being somewhere else in the universe that we could be there?

Just be sure to watch for falling whales.

(Never heard that second part before... in QM c is average? all possible paths?)
alex_caraballo21
1 / 5 (2) Oct 10, 2011
The speed of light is just an illusion because the light being perceived is different than the act occurring creating the light. If a traveler were to take a 4 light year trip the traveler would experience the 4 light year trip as a few hours. He would arrive at his destination in a relative few hours despite the light being emanated from their destination would take 4 light years to get back to earth. Those on earth would perceive the traveler at his destination after 4 years have passed on earth and would think it took him that long to get there when in reality they were at their destination 4 years ago. The closer you get to the speed of light it becomes more instantaneous in relative time to the traveler. The traveler could never go the speed of light because they would have to stop instantaneously at their destination and they could never be able to simultaneously stop and start going the speed of light. The limit of the speed of light is a more perceptual and practical limit
theknifeman
1 / 5 (2) Oct 10, 2011
Yawwwwn, yeah and a quasar can't output 100 bev.
astro_optics
1 / 5 (2) Oct 10, 2011
Well if you could travel faster than instantenious, would not that be like travelling back in time???
rwinners
5 / 5 (1) Oct 10, 2011
Oh come one.
typicalguy
not rated yet Oct 10, 2011
This article is about a topic that will not be relevant to humanity for thousands of years (if ever). Even if a spaceship were capable of traveling close to the speed of light, it would still take a long time to accelerate to that speed, even for the passenger frame of reference. Then you have the problem of slowing down, which you would have to do roughly half-way through your journey, else you'll never be able to stop and explore the new worlds. This deceleration will also take a long time.

Surely the author of the article isn't suggesting instantaneous acceleration to 99.99% the speed of light? That would kill the passengers, same with instant deceleration.
dtyarbrough
1 / 5 (6) Oct 10, 2011
Points in space are only seperated by space. There is no such thing as spacetime. The space between them is the same for everyone, the time is not.
Aliensarethere
5 / 5 (2) Oct 11, 2011
This is actually a crap article. He is using special relativity to say that nothing can travel faster than light. We have known this since 1905. The new stuff is that maybe some neutrinos move faster than light. Special relativity could be broken.
Vendicar_Decarian
0.6 / 5 (39) Oct 11, 2011
"Points in space are only seperated by space." - divabrough

And zero distance for photons. How do you explain that?
Grizzled
2.8 / 5 (5) Oct 11, 2011
Planets A and B are equidistant from Planet C, but on opposite sides. Planet C blows up - so the light from the explosion reaches A & B at the same time. People on Planet A then know that light from the explosion is *ALSO* reaching Planet B at the same time


No they don't. It may very well be that the planet B also has blown away and is no more. Or has wondered off in an unknow direction. Or a cloud of dust got in between and no light reached it ... or ... or ... or ... The possibilities are countless and people on the planet A have NO WAY of knowing which of those possibilites has actually happened. Not until they get some kind of a signal back from B.
Grizzled
3.4 / 5 (5) Oct 11, 2011
Time travel presents paradoxes. Traveling FTL doesn't. So what if you get somewhere faster than the light that left with you?

So what? Let's see. For simplicity sake assume you've found a way to travel instantly. The actual speed doesn't matter. Say as close to infinity as you like. So, assuming instant, you can do this:

Pop a few light year away then back. Then pop right in the middle of the distance. Wait. Eventually, when gravity spreading at the speed of light reaches you FROM BOTH COPIES of you ... bingo! You observe two masses at the distance. Plus your own. And that's not an illusion - they actually exert gravitational pull, add to the total mass of the universe.

Still no problem?
Vendicar_Decarian
0.1 / 5 (35) Oct 11, 2011
"Never heard that second part before... in QM c is average? all possible paths?" - Pyle

The probability of a particle being detected at some point is the sum of the probabilities of it passing through every possible path to reach that point in space and time. The kink is that in computing the probability of a particle traveling through empty space, you sum through all possible scattering events with the vacuum assuming the travel time is zero and the effective speed is determined by a delay in the absorption/re-emission of the particle by the scattering object.

So between scattering events the speed is infinite.

This interpretation of the propagation of particles and fields has been part of QM since the development of quantum field theory, also known as second quantization.

Vendicar_Decarian
0.4 / 5 (37) Oct 11, 2011
"You observe two masses at the distance. Plus your own. And that's not an illusion - they actually exert gravitational pull, add to the total mass of the universe." - Grizzled

Left, Center, Right.

If you are at the center, then when you see the gravittional pulse of your visit to the right, you won't see it from the left because you weren't there.

So you can't be at the center to see two gravitating versions of yourself. But that is a minor point.

The problem with your complaint is that you forget that you aren't at the left when you are at the right. So while you will experience a field to the right and to the left, the field you experience from the right comes at the cost of some region of space not experienceing a field from the left.

The total amount of energy in the universe will remain the same. It will just be distributed differently.

I see no contradiction.
Pyle
3 / 5 (2) Oct 11, 2011
The contradiction in FTL travel is in the acceleration. In order to accelerate to faster than light you would cross some threshold at which you would be moving backwards in time.
The whole causality nonsense is just that.

So what if you see some light you made from two different directions? Or gravity for that matter. You didn't add mass or break causality. You just moved around fast. The problem is that teleportation is make believe, at least on the macro level.

VD, thanks for trying, I think I have to drop the relativity books for a few cycles and refresh on QM.
Cizuz
5 / 5 (2) Oct 11, 2011
The problem with acceralting faster than light is simple. When you acceralate a particle, as it approaches the speed of light the energy required to accelerate it any faster approaches infinity.

However nothing in phyiscs disallows and even promotes the ideas of folding space and moving a small distance but the distance you traveled is connected between two points in space lightyears away. Think worm hole.
joao_m_moreira
5 / 5 (3) Oct 11, 2011
Poul Anderson's "Tau zero" is a very nice hard sci-fi novel where the plot basically revolves around this...
spacegiraffe
5 / 5 (1) Oct 11, 2011
"But you cant do it faster than instantaneously because you would arrive at B before you had even left A."

Actually you can't go faster than instantaneous because Time Dilation is equal to VELOCITY as a FRACTION of the speed of light. This means you're required to travel faster than light speed for this to even be possible.

Also, for those of you who actually learned something from reading this article, welcome to physics.
spacegiraffe
1 / 5 (1) Oct 11, 2011
What we want is to move from one point in space-time, to another point in space-time without leaving the 'normal' earth reference frame we are in. In this way we would be moving faster than the speed of light, as we arrive backwards in time, i.e., at the location we want to go without having to take the 'time', in this case a function of velocity, we ought to have taken to get there.


Well you can't be in the 'normal' frame of reference if you're traveling at a different velocity to the 'normal' frame of reference.

Lets say the journey takes 10 years from the 'normal' reference point and on arrival you're 2 years younger than before you left. You'd have no memory of the last 2 years of your life or the journey. Thus, it's safe to assume you planned this 2 years in advance. From earth's perspective it took you 10 years for you to arrive at your destination so if the destination was earth it would feel like traveling 12 years into the future.
_lack_aiser
not rated yet Oct 12, 2011
An interesting article. But can someone please explain why neutrinos travelled faster than photons? Was time dilated? There has to be one accurate answer, not guesses or opinions.
Pyle
3 / 5 (4) Oct 12, 2011
There has to be one accurate answer, not guesses or opinions.

It is all guesses and opinions at this point. The overwhelming opinion of the skeptics is that the measurement was flawed. I think the leading explanation is an inadequate consideration of gravity's effects on the time keepers, travel path, and GPS measurements. Here is physorg's article on it:

http://www.physor...nos.html

Hmm, only one bite on the worm hole nonsense. Oh well.

More surprising is getting down rated for a Hitchhiker reference. OMG!!! What is physorg coming to?!?
Grizzled
3 / 5 (2) Oct 12, 2011
"You observe two masses at the distance. Plus your own. And that's not an illusion - they actually exert gravitational pull, add to the total mass of the universe." - Grizzled

Left, Center, Right.

If you are at the center, then when you see the gravittional pulse of your visit to the right, you won't see it from the left because you weren't there.

So you can't be at the center to see two gravitating versions of yourself. But that is a minor point.

The problem with your complaint is that you forget that you aren't at the left when you are at the right. So while you will experience a field to the right and to the left, the field you experience from the right comes at the cost of some region of space not experienceing a field from the left.

The total amount of energy in the universe will remain the same. It will just be distributed differently.

I see no contradiction.

Sorry, but I'm afraid I just don't understand you. It's not a quip, not even anything to do with the subj
Grizzled
3.7 / 5 (3) Oct 12, 2011
An interesting article. But can someone please explain why neutrinos travelled faster than photons? Was time dilated? There has to be one accurate answer, not guesses or opinions.


I don't think anyone can, not at this stage anyway. That's the whole point - if they have actually observed what tney say they did - there is no explanation as far as modern physics can tell.
Seeker2
1 / 5 (2) Oct 12, 2011
...there is no explanation as far as modern physics can tell.

Well, maybe. However per http://en.wikiped...illation

...As a neutrino propagates through space, the quantum mechanical phases of the three mass states advance at slightly different rates due to the slight differences in the neutrino masses

Also there is a ...microscopic quantum effect observable over macroscopic distances.

ant_oacute_nio354
1 / 5 (4) Oct 12, 2011
Spacetime doesn't exist.

Antonio Saraiva

matterdoc
1 / 5 (2) Oct 12, 2011
Speed of light is determined experimentally to be a critical constant (in all directions). Therefore, there has to be an external agency that moves light and a logical mechanism that develops, stabilizes and sustain speed of light at this critical constant value. Without understanding this mechanism, it is unfair to speculate on constancy of light's speed or on any particle that may move at greater speed.
Vendicar_Decarian
0.4 / 5 (37) Oct 12, 2011
"But can someone please explain why neutrinos travelled faster than photons?"- lack

I think it best that you wait for confirmation that they actually exceeded before asking such a question,
AWT
1 / 5 (3) Oct 12, 2011
IMO the space-time can be modeled with phase interface of supercritical fluid and after then the photons are subluminal solitons resulting from mutual interference of transverse waves with bulk waves of heavier phase and the neutrinos are superluminal solitons resulting from mutual interference of transverse waves with bulk waves of lightweight phase.
Seeker2
1 / 5 (2) Oct 12, 2011
Look at it this way. Photons get on the conveyor belt and go for a ride. Neutrinos however get on the conveyor belt and do backflips as they change type.
Seeker2
1 / 5 (2) Oct 13, 2011
Actually if neutrinos have mass they would be subject to the Heisenberg uncertainty principle. Since their mass is small the uncertainty in momentum is small so their uncertainty in position would have to be very large.
Prbsolver
not rated yet Oct 13, 2011
Whats the point...
Lets say i was intrigued by a specific Location. The Driving factor to go to that location will be long gone by the "time" i get there.. Before humanity starts its journey to the stars i imagine there will be a need to have "Real Time Knowledge" of that destination. Could be done with Quantum Computing Simulations i suppose. Or better yet, if they could somehow use Quantum Entanglement to measure or monitor the surroundings would be ideal. Just a thought
GoodElf
3 / 5 (2) Oct 13, 2011
Forum Nazi's take a very dim view of ideas not in accord with dumb "populist" notions how Einstein's Relativity works. Actually photons are connected "instantly" in space and time from their source to sink via many paths. This "connection" is along a null geodesic - zero length and zero time which applies only in the "rest frame" of the photon. This "means" that light is a point to point "bosonic force carrier" when it is "on shell". "Off shell" all force carriers become "fermionic" and show mass which limits both range and velocity to below the speed of light. A recent paper in arXiv Repository confirmed this conjecture mathematically.

A corollary of this would be if it were possible to remove all "mass" a fermionic particle could move "off shell" anywhere in the universe at the speed of quantum entanglement. This is because Relativity is just two basic laws... length contraction and time dilation - their mutual effect is to hide all distortion from all internal temporal measurement
Daleg
3 / 5 (2) Oct 14, 2011
The Article is brilliant because it stresses the point that instantanous means just that, no passage of time at all. You can't beat that. Going backwards in time is all well and good, but we have never seen anything doing so, and I really wonder what kind of effect it would have if we did. ESP? or knowing what will happen before it does? Logically that is what we are contemplating, if something can travel from it's source to it's destination before the cause which created it, then that something had no cause.Since an "event" in our logic as we have developed the systam we call causality, must "happen" to produce a result, you need to explain not how a particle can arrive at a destination early, but how an effect originated at all, since logically if it arrives prior to instantanously, it had no prior causation.
Daleg
3 / 5 (2) Oct 14, 2011
I stress that the nuetrinos in this experiment were emitted from a particle beam from the collision of Protons, and the experiment was to measure thier travel time from point of emission to point of detection. Logically what the results are stating is that these nuetrinos arrived at Gran Sasso before they were emitted. I realize we are talking about a measurement of the travel time from point of emisssion to point of detection, but as the author here stresses, light speed means travel through space, in zero time, you can't arrive anywhere before you exist. the problem as he well points out is just that, no cause, means there can be no effect, no matter how you measure it, by QM, GR or even classically, if the particles don't exist prior to thier detection, they can't be measured, and certainly can't arrive anywhere at all.
Daleg
4 / 5 (2) Oct 14, 2011
In experiments conducted in the 1960's it was shown quite clearly and mathamatically that if time reversal were to ocurr then other violations of the natural physicalorder and processes would also happen. For instance in the decay of a cobalt nucleus it is well known that the neutrino is always emitted with a right hand spin. Analogous to time reversal the mirror image would present a physical impossibility or a left hand spin nuetrino, can't and does not happen. Some things are clearly a violation of the rules and simply are not allowed to happen.If nature herself abhors under certain circumstances time reversal, what in the world makes anyone think it is possible for the self same nuetrinos to actually produce results indicating it does happen?
GoodElf
5 / 5 (2) Oct 14, 2011
Hi Daleg,

The Article is brilliant because it stresses the point that instantaneous means just that, no passage of time at all. You can't beat that. Going backwards in time is all well and good, but we have never seen anything doing so, and I really wonder what kind of effect it would have if we did.ESP?
It doesn't happen - no effect can preceded it's cause. Backward time travel has nothing to do with traveling faster than light... except in Superman Movies. However... "instantaneous" is not really "instantaneous"... depends which inertial frame you measure time in if you are a beam of light then no time passes (for the beam) but if you are a casual observer then millions of years can pass waiting for it's return since the ultimate speed is C. No confusion here... Relativity gives on one hand and takes with the other. A trip around the Galaxy is a one way trip into the future for a near light speed traveler and those left behind would be dust long before he returned.
Callippo
1 / 5 (2) Oct 15, 2011
Forum Nazi's take a very dim view of ideas not in accord with dumb "populist" notions how Einstein's Relativity works. Actually photons are connected "instantly" in space and time from their source to sink via many paths.
The word "actually" implies, such an interpretation is the only one correct (and verified) one - but it could be just one of many possible interpretations of how relativity works (despite of it could be quite relevant or not). And it's still unverified indeed - the word "actually" should be used with extreme caution here.

I tend to judge such an interpretations rather by their ability to predict: is such view able to predict something, which we still didn't observe? If not, why we should adhere on interpretations of reality, which provide nothing useful for us - they just require us to replace the belief in one concept with belief in another one?
bluehigh
1 / 5 (2) Oct 15, 2011
Causality varies
- some dill

In reality, effect always follows cause. Always. Its a basic property of existence.

So between scattering events the speed is infinite.
- Vendi

Not in reality. It requires time to elapse for change to occur. No infinite speeds except in thought experiments or computer models. A weekend treat Vendi to see you turning on your intellectual capacity and communicating in more detail.

Callippo
1 / 5 (2) Oct 15, 2011
effect always follows cause. Always. Its a basic property of existence
It's basic definition of causality and logical arrow of time. But this arrow can be broken. For example, when you hear a weather forecast, you'll do effect, which apparently advances the cause.
Burnerjack
5 / 5 (1) Oct 15, 2011
Math has never been my strong suit, but if you have 99.99999% of something, no matter how many 9s you add, the total is always less than 100% let alone more than that. Is this statement not correct? If so, the statement of "... reaching Alpha Centauri in a matter of days..." is just wrong. I suspect that there are theoretical physicists out there laughing and hoping nobody catches on to the absurdity of their "research" and kills their funding. Nevermind the forest people, look at the trees...
GoodElf
5 / 5 (1) Oct 16, 2011
GoodElf said:
Actually photons are connected "instantly" in space and time from their source to sink via many paths.

Callippo said:
The word "actually" implies, such an interpretation is the only one correct (and verified) one
And that is what we "actually" measure. Photons do not "age" and they travel on null geodesics while obeying QED. There is nothing novel in this. It makes predictions and it has all been verified. Until something else comes along there is nothing better.
I tend to judge such an interpretations rather by their ability to predict
"Actually" - you don't!!... You do not accept the result of experiment and you tend to make it up as you go along without a resolution. You predict nothing for a test. It is OK to be wrong sometimes - ultimately all science is "technically" wrong - but is the best we have presently as a basis for future action. You may have your religion or beliefs as a "guiding star"... maybe? I suggest that is a poor basis for action.
Callippo
2.3 / 5 (3) Oct 16, 2011
Actually photons are connected "instantly" in space and time from their source to sink via many paths...It makes predictions and it has all been verified..
You're just saying so - but which particular predictions do you mean exactly? I mean, which TESTABLE predictions we could DERIVE from the assumption "all photons are connected instantly in space and time from their source" in sequence of irrefutable logical steps?

Show us.
hard2grep
1 / 5 (2) Oct 16, 2011
imagine how much braking force exerted on the earth would be from ships that decelerate from.. I don't know, 9/10ths the constant. Yes, the ships provide their own thrust, but where does the braking give its blow. Maybe Jupiter could share the load.Face it, future space travel will be generational. little colonies sprinkled out into the tides of time...
gusycs
5 / 5 (1) Oct 16, 2011
"So, you cant move faster than light not because of anything special about light, but because you cant move faster than instantaneously between distant points."

So the author says that an experimental result has no sense because it contradicts
an established theory, he tries to invalidate an experimental result using the theory that is
questioned... of course it has no sense within the logic of special relativity, but does the michelson-morley
experiment result or the relativity of simultaneity have any sense using the logic of newtonian mechanics?
Come on...
mlvols
not rated yet Oct 16, 2011
That curve... It's a sign! It's the Singularity! [/sarcasm
Daleg
5 / 5 (1) Oct 16, 2011
Hi Goodelf, you have a valid point, except in the issue at hand. The issue here is that relativity is predicated upon some basic tenets, one of which is that the speed of light is a zero reference point for time. The whole premise behind setting time to zero when you reach light speed was based on the observed fact of the speed of light never varying in a vacuum. As most relativist's state the issue, when traveling at light speed time simply drops out of the equations. In that sense the concept of something traveling faster than light speed makes no logical sense at all. If once you reach light speed time vanishes, then by what reason or logic could anything have a valid measure to be tested by. Time does not exist anymore so what then, faster than light or instantaneous both become irrelevant. Negative time or reverse time means a total breakdown of logical sequence and thus randomness with no sense of a measurable order of events, thus by any logical premise you have nonsense.
hush1
2.3 / 5 (3) Oct 16, 2011
lol
I can imagine myself becoming a fanboy of null geodesics.
If all forms and shapes without a hole is a sphere, then geodesics will fill anyone's demand for a model description of reality.

lol mlvols. Yes. Curvature or bust.
Daleg
not rated yet Oct 16, 2011
I should clarify this a bit. Of course as I said these nuetrinos were emitted from a proton beam at CERN along with the photons which were measured as well. Therefore from the reference frame of the experiment both would take some time to cover the distance, True enough. However, to make sense of a faster than light particle, I stress time vanishes at light speed, anything produced in this way should never ever as the author states travel relatively faster than light, since in essence this means 0 time. The logic is that the nuetrinos would need to be produced 60ns before the photons, to arrive first. That is why I stressed the point, since you can't have particles emitted from a process 60ns before it happened, as the theory states that anything that travels at light speed experiences no such thing as time, so faster than light speed is outside of our established reference frame for time, and any such result is non-sensical in that regard.
hush1
3 / 5 (4) Oct 17, 2011
Delag
Not even wrong. No one asks to adhere to any logic. Nature has the final say. Your model and math are consistence when nothing Nature offers contradicts your model and math.
Daleg
not rated yet Oct 17, 2011
Hush1 The math is meant to model the observations not the other way around. First Einstein based his model on the observed speed of light in a vacuum then he determined what this would mean from the reference frame of time. Logically from a time constraint viewpoint light always propogating at the same speed and an inability to travel alongside it and see it at rest means you can't travel at light speed ipso facto it was determined from observational fact that this is an impossibility. Thus Einstein built his theory around that fact.The odd thing is that the math confirms the observation, that is why time drops out of the equations. The actual physical conceptualization is way beyond the math, weirdness is just well, weird. Setting the speed of light as the limit was a choice, once set however it became the reference point which ever since our definition of time has been based on.
Daleg
not rated yet Oct 17, 2011
Of course you would say our definition of time is wrong, but that is the very reason why physicist's are very skeptical of this result. Because in theory light speed = 0 time, so by definition what does the concept of less than zero mean. Talking of time does -60ns make any sense? Not by any definition that would decribe the physical universe we are supposed to be studying in these experiments, as our definition of zero time means something travels at light speed ala Einstein. I reiterate, if nuetrinos are as measured superluminal cause and effect are out the window.
GoodElf
5 / 5 (2) Oct 17, 2011
GoodElf: Actually photons are connected "instantly" in space and time from their source to sink via many paths...It makes predictions and it has all been verified..
Callippo: You're just saying so - but which particular predictions do you mean exactly? I mean, which TESTABLE predictions
Two points.. the debunked theory of "tired light"
http://en.wikiped...ed_light
and that photons must travel a "null geodesic" that is the sum of the squares of the time and the length is identically zero.
http://en.wikiped...ivity%29
The first is fully tested indicating the adherence to special relativity exactly when traveling in the vacuum the photons do not get "tired". As a consequence the second means that the photons move on a path (in the frame of light itself) where the time dilation and length contraction are both infinite.

This does not mean that time and distance in other frames are zero... quite the contrary. All "fully tested".
bluehigh
2 / 5 (4) Oct 17, 2011
Curvature or bust
-hush1

A spelling mistake surely. You did mean Curvature OF Bust or are we looking at different pictures?

@GoodElf, you read it in Wikipedia so it must be true - NOT. Try again with verifiable references from a reputable source and not a second hand exposition from unqualified lay editors.

GoodElf
3.7 / 5 (3) Oct 17, 2011
Hi Daleg,

If once you reach light speed time vanishes, then by what reason or logic could anything have a valid measure to be tested by. Time does not exist anymore so what then, faster than light or instantaneous both become irrelevant.
Not so time is continuous and still exists. Depends "where you stand" as to how much time elapses and this is related to distance in a relative frame.

The point is relativity hides internal problems and you are always "at rest" in your personal "rest frame". Relativity is simply stating the case for simultaneous time dilation and length contraction. The only "time travel" is the one Feynman agreed to being normal particles traveling backwards in time in their own frame and observed from our causal "forward in time" frame. Time travel involves conservation of and antiparticles are the case of a single particle observed causally. The interpretation is called the Feynman-Stueckelberg Interpretation of antiparticles
GoodElf
not rated yet Oct 17, 2011
Hi Bluehigh,

Do your own research... do not request me for anything... thanks!
bluehigh
1 / 5 (2) Oct 17, 2011
GoodElf, sure no problem because you are certainly incapable of useful research and your argument is just your worthless opinion in the absence of any verifiable references.

The question remains ...
You're just saying so - but which particular predictions do you mean exactly?


I guess Wikipedia couldn't help you with that.
Pyle
not rated yet Oct 17, 2011
@GoodElf:
"Off shell" all force carriers become "fermionic" and show mass which limits both range and velocity to below the speed of light. A recent paper in arXiv Repository confirmed this conjecture mathematically.
Could you post the ID for this? Sounds interesting. tks.

@bh, Just follow the references on the wikipedia page if you want more. There is plenty on the web regarding tired light and geodesics if you just google it. Not hard to find. Try adding to the conversation rather than just chiming in with negativity.
And on that note, I formally apologize for this comment. I am the pot.
GoodElf
5 / 5 (1) Oct 18, 2011
Hi Pyle,

Thanks for your interest - you might find this preprint enlightening.
Entanglement entropy in all dimensions - Samuel L. Braunstein, Saurya Das, and S. Shankaranarayanan
http://arxiv.org/...0.1239v1

It is a generalization of a "Holographic notion" that now has gauge independence and has deep philosophical implications. The analogy in condensed matter might be like the behavior of composite fermions in 2D being being "free" surrogate "bosons" like light while the emergent property of mass in 3D being likened to "fermions" when drawn out from the surface.

This relates to some concepts recently discussed in this prize winning paper...
On the Origin of Gravity and the Laws of Newton - Erik Verlinde
http://arxiv.org/abs/1001.0785

"On shell and off shell" can be looked up here...
http://en.wikiped...ff_shell
Unfortunately this is not the place to fully describe all of this but you can have a lot of "fun" thinking about it all carefully. I know I did.
Pyle
not rated yet Oct 18, 2011
To beat a dead horse.
(Links to outside sources)
(Brief discussion)
Unfortunately this is not the place to fully describe all of this but you can have a lot of "fun" thinking about it all carefully. I know I did.

I think this is why most of us are here.
Thanks GE.
I'll keep Verlinde in mind when I go through your first link. The Wikipedia link is a terrible one. It doesn't supply references or links to further discussion of the term, which correctly qualifies it for bh's above comments. It should be edited to include at least a link to a paper that does something "off shell".
Daleg
not rated yet Oct 23, 2011
Hi Good Elf, Thanks for the explanation, what I am reffering to is theory, based on the idea of instantanous, as opposed to
our perception due to exactly what you reference "our rest frame". That is the whole point behind this. Time travel is not an option, as you say Feynman/Stuckleberg well explain this and why. That is the sense in which I was pointing out that you can say time vanishes mathematically, losing any sense of measure except from the reference frame of the object under consideration. Thus for light time does not exist. Yet for us observers from our rest frame time does exist, that is why there is a seeming paradox. The illusion is an effect, not real, so essentially you are correct time continues to exist, and cannot vanish. An illusion, but with measurable consequences, where it is well worth remembering that something like Gamma Ray Burst particles only reach Earth exactly because of time and distance contraction at relative speed.
Callippo
1 / 5 (2) Oct 23, 2011
Gamma Ray Burst particles only reach Earth exactly because of time and distance contraction at relative speed
The gamma ray burst photons can all move with different speeds and yet come to Earth simultaneously. Their trick is, the photons of short wavelength are heavy, they exhibit their own gravity field and the lightweight longwavelenth photons tend to encircle them along spirals.

This explanation has even its testable consequences. The gamma ray photons in less distant bursts (MKN501) are delayed from visible light more, than the photons from very distant explosions (GRB090510). Why? Because at the case of very distant bursts only photons traveling in compact planetary system can survive the long path across CMBR noise without mutual dispersion. We are facing rudiment of cosmologic evolution here.
Seeker2
1 / 5 (2) Oct 23, 2011
GoodElf:
...A corollary of this would be if it were possible to remove all "mass" a fermionic particle could move "off shell" anywhere in the universe at the speed of quantum entanglement.

I've been wondering about this. What is the speed of quantum entanglement?
GoodElf
not rated yet Oct 24, 2011
Hi Daleq,

Yet for us observers from our rest frame time does exist, that is why there is a seeming paradox. The illusion is an effect, not real, so essentially you are correct time continues to exist, and cannot vanish.
No paradox -- it is only the rest frame of light that is impossible for us, as "living creatures", to experience. Photons have suffered infinite length contraction and infinite time dilation. This leaves only quantum photon end processes at the source and sink left - an exchange "force".

All of our "motion in time and space" when referenced to our rest frame sees light at a constant velocity. Moving towards or away from a light source changes the frequency but leaves the velocity unchanged because light is our internal measure of time and space and all relative changes compensate for our intended motion through dilation and contraction along our "path" as we "chase" it keeping light's relative velocity constant. It is no paradox really and it is not an illusion
GoodElf
1 / 5 (1) Oct 24, 2011
Hi Seeker2,

I've been wondering about this. What is the speed of quantum entanglement?
That connection "speed" is infinite. So far this "instantaneous connection" has not allowed the transmission of information. However is an experimental fact that non-local connection is well known and has been performed making particles that are separated to behave in perfect "quantum synchronization". It is even possible to "send entanglement".

Once established entanglement links source and sink instantaneously (in Wheeler-Feynman Absorber Theory) through advanced and retarded potentials... though it is not possible to measure the advanced "waves" because they propagate "anti-causally" we can measure instantaneous entanglement and it is the next best thing. The advanced and retarded waves "mix" to produce a spatial traveling "wavepacket" for the photon. Entanglement is the way source and sink "know" about each other and "know" how to connect instantly.

See quantum pseudo-telepathy..