Crawling at the Speed of Light

Typically modern situation: the life without good theory: so much work ("over 50 research groups") and so little to show for it. ;-)

As the saying goes, one must crawl before one can walk. Persistent research in the right direction may be slow, but the rewards are proportionate to the risks.

Tom

Not new guys. Feynman commented on Lene Hau slowing light down to 30mph in BEC in the 1950's. She first stopped it dead a few years ago (Harvard). But we haven't been brilliant in analysing, applying or drawing any conclusions yet.

For any proponents of ballistic photons, any idea how it instantly achieves almost 300,000 miles/sec when released? (which it does).

Or precisely how it does an instant sharp left turn entering a prism at full speed?

Or how it reaches superluminal velocity when the scattering harmonics are right in the absorption bands each side of the visible spectrum? (which it does).

Can anyone help here?

Peter

We live in the transitional period (of unprecedented scale). "Crawling" will not get you across the huge fissure, which has been expanding over the last century.

We need huge and "calculated" jumps. ;-)

My understanding is that the photons themselves aren't slowed down, being massless they must travel at light speed (or close to depending on the medium), but in a dense enough medium or at least one which initiates a very strong coupling to photons, eg Bose-Einstein condensates, a light beam can be slowed due to the strong coupling or scattering of it's constituent photons. So that "when released" from the medium, the photons resume their naturally *straight* trajectory correlated as a beam, without changing velocity.

As for superluminal velocity, I don't understand what you are saying Peter? You seem to be implying that in the UV & IR spectrum photons can exceed 300,000 kms/s in conditions which becomes apparent in the visible spectrum?! Or are you talking about Cherenkov radiation?

Cheers

Roy,

Thanks. That seems only a very loose fit with the Hau lab and others, where the findings seem more consistent with classic superposed wave energy rather than discrete photons. I also don't understand your solution to how they can be slowed right down and stopped 'frozen', then going instantly back up to 'c'; 'without changing speed.' Unless of course 'c' is just relative, which seems to rather opens up a whole can of worms with relativity.

The FTL conditions are simply where 'n' becomes slightly less than 1 for short bands between visible, IR and UV. A similar phenomena to Cherenkov but due to relative scattering harmonics at those wavelengths not the emitter itself moving. I gather we're now up to over 50 'superluminal' cosmic sources, mainly Quasar gas jets, and in quantum optics and 'tunneling' relative superluminal motion is now very common, but only proving c/n in a dielectric 'irrespective of the relative speed of the observer', which has never anyway proved false. It may often be looked at as 'group velocity,' with FTL signalling not yet proved. There are very many PR papers, I'll put a link to one below.

Peter

Superluminal聽propagation in resonant dissipative media聽聽Original Research Article Optics Communications,聽Volume 282, Issue 6,聽15 March 2009,聽Pages 1095-1098 P. Chamorro-Posada, F.J. Fraile-Pelaez

As a beautiful color of meconopsis betonicifolia, the radiations around the heart of a nuclear system seem showing the road ,because it's the water of course and its radiations due to the v of the particule.The blue is beautiful as the UV.

At my knowledge for the Chernkov effect.

n .....implies c1=c/n.......the particles emits due to the particle as a choc of wave.a little as the sound and an airplane ,we put a particule for an airplaine and we see the cherenkov radiation.

The mach number I suppose can be extrapolated and improved.That permits simply to know the mass easilly.

We see an equilibrium at the instant of shock.It's important this return at the equilibrium emmiting radiations due to the interaction.

If the perception can imply acceleration and decceleration where light ......what I find interesting is the fact what the centers of galaxy can have acceleration passing our perception.But above the ligtht perception thus, that's why peter we can't see them in logic .

Steve

Peter,

The way I see it is that they are controlling to a very high degree the interaction between the medium, hot gas, condensate etc, and the photons. The *appearance* of individual photons being slowed down or "frozen" would be due to the way the light pulse is effectively "contained" by an extremely strong interaction coupling, I don't think they are claiming to stop light/photons completeley, just to a workably slow speed for manipulation & information processing.

The FTL phenomena you mentioned do seem to be, as you say, a classical wave interference effect. A quick look at the abstract of the work you linked to seems to be talking about an artificial set up for the interference of an input wave with a resonant wave so that the superposed state may have modes that *effectively* to propagate FTL? (I think Special Relativity would still be safe!) But I need to understand it much better to have anything really worthwhile to say!!!

Cheers

You're right, Roy. A common misconception is that special relativity forbids faster than light travel. Not exactly true. Special relativity is classical -- the theory says that particles cannot communicate at speeds faster than light. Entangled massless particles like photons obey quantum statistics; particle state changes do not imply that classical relativity is violated, since the particles are not communicating with each other in the classical (local) sense -- it's just that what one knows about one particle determines the state of another. In the context of the experiment, the quantum state is communicating with the experimenter in the classical domain, so no signals are being exchanged faster than light. This is an obvious crucial requirement for quantum computing, because infomration in a superposed state is not useful to us in the classical world in which we live.

Tom

Lev,

How would one know that one is living in a transitional period? It seems to me that, like the continuum hypothesis, one can assume it or not. In a historical record one can differentiate periods of stasis from big spikes, but the record is scale dependent, in a world that is apparently scale invariant and infinitely self similar.

Tom

Tom,

As a hint, let me give you for starters this quote from "Metaphysical Foundations of Modern Science" by E.A. Burt (1924):

"It does seem like strange perversity in these Newtonian scientists to further their own conquests of external nature by loading on mind everything refractory to exact mathematical handling and thus rendering the latter still more difficult to study scientifically than it had been before. Did it never cross their minds that sooner or later people would appear who craved verifiable knowledge about mind in the same way they craved it about physical events, and who might reasonably curse their elder scientific brethren for buying easier success in their own enterprise by throwing extra handicaps in the way of their successors ...? Apparently not; mind was to them a convenient receptacle for the refuse, the chips and whittlings of science, rather than a possible object of scientific knowledge."

Lev,

I prefer Karl Popper's view of "metaphysical realism" (Realism and the Aim of Science, 1983).

If "mind" plays a role, does it differ from the role of brain mechanics? If not, then "... verifiable knowledge ... about physical events ..." is just another physical model of a metaphysical reality.

Tom

By the way, Popper was a superficial epistemologist, whose fame was mainly due to his political leanings and a clear writing style.

Coming back to your question about why the current period is transitionary, here is Thomas Nagel in "The View from Nowhere", 1986:

To insist on trying to explain the mind in terms of concepts and theories that have been devised exclusively to explain nonmental phenomena is, in view of the radically distinguishing characteristics of the mental, both intellectually backward and scientifically suicidal. The difference between the mental and physical [as we understand it now] is far greater than the difference between electrical and mechanical. We need entirely new intellectual tools ... .

I find Popper far from superficial. Though I admit that my personal philosophy is more Rational Idealist than Critical Rationalist (Popper and his followers), his method does provide a test for clear demarcation of science from nonscience, an important departure from the Logical Positivist school that dominated philosophy of science before Popper. Popper's political views are independent of his philosophy of science, though I also endorse the Open Society as requisite to scientific advancement.

I don't know what Nagel means by "nonmental phenomena." We have no other means of interpreting reality other than by theory (another Popper standard) which is most certainly a mental phenomenon. If there is truly a difference between mental and physical, we could only explain it in terms of physical principles.

Tom

"If there is truly a difference between mental and physical, we could only explain it in terms of physical principles."

Yes, of course, but we need to generalize the "physical", so that the boundary between the physical and the mental disappears, and this is precisely what I called above the transitional period. Because of ETS formalism, for me, this transitional period is not as intimidating as it could have been.

As far as Popper is concerned, the mess he made of induction shows him as a superficial epistemologist.

Hi,

very interesting.

If you think it's possible to create an artificial intelligence.

No.

Because the biology is deterministic.

If you extrapolate with the ideas, relevants, of Mr Penrose, you shall see the necessity of calculation of the quantic mesure.

The reduction of waves is also interestings in a deterministic point of vue.

We arrive at the pure link consciousness/physics dynamic.

The formalism is about algorythms and this determinism is coded by humans.

Godel ????it's why we can't interpret without the universal rationality.

Cantor.....the infinity ????

NEVER WE COULD REPRODUCE THE UNIVERSAL CODES, INTRINSIC IN THE GRAVITY.

THIS FORMALIZATION IS DETERMINISTIC IN ITS PURE CODE BUT INDERMINISTIC FOR OUR PERCEPTION DUE TO OUR WALLS.

A HUMAN FORMALIZATION OR THE UNIVERSAL FORMALIZATION!!!!

Steve

It's impossible that the light pass this c limit.

But on the other side , non perceptible particles are possible above our light limit of perception.

Hope you understand what I say.In fact theses effects are just optical effects as M87.

If you want find a speeder particle,search in the invisibility due to our special relativity.

If it exist an accelerator, there also we can't see them .

Steve

The "mess" he made of induction? Popper was the _only_ philosopher of his day that I know of, who took seriously Hume's skeptical problem, and rose to the challenge. Science is absolutely not based on inductive results -- there is a strict demarcation between science and philosophy.

At any rate, though, I agree that there is no natural barrier between physics and "mind." To make the point correctly, however, I think we have to speak in terms of brain-mind mechanics so as not to imply an independent mind.

Tom

"Popper was the _only_ philosopher of his day that I know of, who took seriously Hume's skeptical problem, and rose to the challenge. Science is absolutely not based on inductive results -- there is a strict demarcation between science and philosophy."

I strongly disagree!

Popper was not the only one of his day who took Hume seriously, but he certainly was almost alone in seriously denying induction.

I strongly believe--as did, for example, Helmholtz and Poincare--that induction is the main underlying principle we need in science, which implies that classes (of processes) are the main feature in the informational organization of Nature. And since they are basically missing from physics (and mathematics), we are facing "the huge fissure" I mentioned above.