Liquid vortex (LV) sheds light on some black holes (BHs) essentials.
Gravity-driven LV is seemingly a generic analog of BHs.
Here are some exciting things about the BHs I have learned assuming this analogy
Abstract. Vortices of different kind could be found everywhere around. One can get an insight in understanding the hardly observable vortices of interest by studying the easily observable generically similar ones.
A simple gravity-driven (bath tub) LV I have observed was located in the middle of a pond and arranged confining its developments predominantly in the thin water surface layer making it acting similarly to a two-dimensional cosmic one. For the LV observed, quite a number of seemingly generic features, appeared to be coherent with those known for the cosmic BHs, so, I hypothesized that it would be odd not to consider both vortices to be, in general, analogous. Analysis of the observations, based on the analogy assumption, lead me to a striking grasp, possibly questioning even the widely-adopted views on the dark matter and energy.
Here is the list of matters I am going to discuss in this summary:
The “spinning” LV was observed of permanently generating double-spiral waves (DSW).
Stop and use the settings (flower button at the right lower corner) to set the lowest possible speed (().25). Then continue
In the light of the hypothesized analogy, this should mean that the “spinning” BHs also should generate spiral waves, gravitational in the BH case. Which, actually, was predicted by Albert Einstein. Generated by multiple BHs these waves, being even of very low amplitudes, in long term form a cumulative rippled all-over-the-universe energy-rich gravitational background (dark energy???).
Combined action of the incoming vortex flow and generated outgoing DSW make the water surface around the LV to warp and whirl. In the same way, combined action of the BH-generated whirling distortions and gravitational spiral waves also must make the BH- nearby spacetime to be whirled and warped.
Recently, wobbling effects were observed for some BHs. In the LV case, the DSW swelling out of the LV epicenter (shown at the upper featured image) in dynamics also appears as being wobbling.
It is suggested, based on the LV-BH analogy, that it is possible to interpret the galaxies rotation anomaly and the universe accelerated expansion on the basis of the DSW propagation dynamics with no necessity of introducing the dark matter and the dark energy hypotheses.
On the basis of the assumed analogy, the matter and the spacetime should be adhered to each other as an inseparable duo: where the spacetime there the matter. And vice versa.
The BHs are thought to pull and drain not only the matter but also the spacetime, whirling around the BH in the same way as liquid whirls while flowing into the LV.
When a handful of shredded dry leaves was spread over the LV area they were arranging in a spiral galaxy-like pattern. It is obvious that the dry leaves were not informed that they need to form some specific collectively arranged shapes. So, it is concluded that these are the whirling waters guiding the floating leaves to arrange in spirals. For the galaxies, similarly, the spacetime, whirling around the BHs, is suggested of directing the galactic matter to shape up in spirals. Actually, in both LV and BH cases, the floating stuff, the dry leaves and the regular galaxy matter, correspondingly, just decorate the structural profile of the whirling medium they are “floating” over, namely, of the water surface and of the spacetime, correspondingly. Decorate in the same way as criminal investigators powdering the surface to decorate fingerprints making them visible
The specifics of the particular BH spacetime whirling dynamics seems to have a direct effect on how pronounced the galaxy shape appears.
The BHs act as matter consuming power plants, however, also spreading part of the acquired mass/energy back into the universe as gravitational spiral waves. Being of a very large wavelength and low amplitude, these DSWs are hardly observable. However, these waves, accumulating, in long ran, form an energy-rich universe-wide rippling gravitational background
My simulations also showed that:
If the BHs are not rigid formations then, due to their inevitable vibrational shape instability inducing spacetime perturbation, a bulge and a surrounding it gravitational ditch, are probably to appear.
Existence of bulge was already observed for some BHs. Most probably, indicating that a gravitational ditch next to the bulge collecting the regular matter also exists.
Acting as a gravitational halo…
Intro. Vortices could be found everywhere around us, in any continuous medium or any system having continuous medium as one of its basic components. Some of the vortices are too large, or too small, or located too far away, others require sophisticated tools to research them, which altogether forces scientists to come up in their theoretical models with scientific guesses to be tested against the vortex observable properties. However, if different kinds of vortices are found to have a number of generic commonalities, then observing the easily observable ones (for example, LVs) could be of great assistance in constructing assumptions projected to be applicable for the hardly accessible ones (for example, BHs). Exploring LVs allows to run the observations with reasonable resources, in reasonable time, under variety of conditions and also to observe the developments beneath the funnel bottom
The LV, a simple gravity-driven bath-tub vortex type, I observed was located in the middle of an extended pond and structured to confine its developments in the thin water surface layer, minimizing the action dissipation into the depth, making the LV to act rather as a two-dimensional one thought to be better related to the BHs. Collection of the related videos recorded could be accessed at https://www.youtube.com/user/YehielGotkis or https://www.youtube.com/user/YehielGotkis/videos?shelf_id=0&view=0&sort=dd. The images and video clips were made in 2007-2008 with camera, considered advanced at the time. Please, slow down the video rate as much as your application allows to see better the details.
I have already published rough notes on this matter in an old blog in late 2011 and later at Linked In (permanently updated) addressing the LV clearly observable features.
I compiled a more detailed summary with revised conclusions, which I would like to present for your considerations here and would like to start it with the mostly revealed and, to me, the most important LV feature – emanation of DSW.
- Emanation of DSW. The permanently generated DSW were propagating away from the LV keeping their amplitudes significantly high down to the pond banks (Fig 1). The DSW two arms are clearly traceable at the magnified vortex central section in the Figure 1b and in the upper featured image above.
The DSW generation, to my opinion, is a critically important LV phenomenon because the spiral waves carrying momentum having both angular and radial components, (cumulatively) transfer it (and associated kinetic energy) to material objects on their way influencing their angular and radial movement. If the LV-BH analogy is applicable, it can explain a number of phenomena associated with the BHs, galaxies and even the Universe.
Figure 1. Liquid vortex emits double spiral waves: a) large scale view; b) magnified proximity view to assist in tracing the double spiral.
- The generation of the DSW was found to be associated with the dynamic distortion of the (spinning) funnel bottom, which most of the time was shaped as an ellipse or as a distorted digit 8, as it is shown in a snapshot in the Figure 2a. A spinning double-spiral rim (see the lower featured image) “carved” by the spinning asymmetrical bottom was rising and unfolding as an outgoing DSW while turning over the upper surface (see the top left image).
The bottom distortion was caused by another seemingly intrinsic vortex feature – a couple of extending down strings “attached” to the funnel bottom and twisted also as a double spiral – a unique feature, clearly observable from the vortex side view, thanks to the water transparency (Figure 2b). It is guessed that the upper and the lower spirals are actually the two ends of the same double spiral heavily twisted at the swiftly spinning funnel bottom.
Figure 2 and video. Asymmetric shape of the vortex bottom and its cause: a – bottom asymmetry shaped as distorted digit 8; b – beneath the bottom strings twisted as an extending down double spiral.
It is critical to note, that
The LV distortion – the cause inducing the DSW generation, was developed naturally, as an intrinsic property of the LV without any external triggering or initiation disturbances.
It allows to suggest that, as the intrinsic vortex property, DSW generation may, and most probably should, occur for any kind of vortices, including the BHs.
- The Universe must be filled with gravitational ripples. The”spinning” BHs, being even slightly asymmetric, even temporarily (which seems to be unavoidable), should also generate spiral waves, in this case, gravitational ones modulating the fabric of the spacetime. Which, though being extremely hardly to observe due to their extended wavelength and very low amplitudes (as Albert Einstein expected), if generated permane ntly, in cosmic timescale, should pump into the spacetime quite a significant amount of the acquired mass/energy. Meaning that the universe should be filled with the energetic gravitational ripples (Dark energy?). Like the rippled surface of the ocean.
Gravitational waves may also carry away some of the BHs accrued information.
- The DSW (shown at the upper featured image and in the images above) while swelling out of the LV epicenter looked as even being wobbling (see also the video below), which correlates with the recently observed Quasi Periodic Oscillation (QPO) phenomenon, suggesting a simple interpretation for it.
And the recently observed BH wobbling effect (Scientists Observe Material “Wobbling” Around a Black Hole, http://www.outerplaces.com/science/item/12733-scientists-observe-material-wobbling-around-a-black-hole#comment-3109063838) in this light could be considered as an indication of the spiral gravitational waves generation by the BHs.
- The DSW generation by a vortex, to my opinion, is a critically important phenomenon because the spiral waves carrying momentum having both angular and radial components, (cumulatively) transfer it (and associated kinetic energy) to material objects on their way influencing their angular and radial movement. If the LV-BH analogy is applicable, it can explain a number of phenomena associated with the BHs, galaxies and even the Universe.
- Spaghettification. “In astrophysics, spaghettification (sometimes referred to as tidal disruption, or the noodle effect) is the vertical stretching and horizontal compression of objects into long thin shapes (rather like spaghetti) in a very strong non-homogeneous gravitational field; it is caused by extreme tidal forces. In the most extreme cases, near black holes, the stretching is so powerful that no object can withstand it…“ [https://en.wikipedia.org/wiki/Spaghettification]
A very similar phenomenon was normally observed with the LV when floating foam patches were pulled into the funnel. The image in the Fig. 3 shows such a case when a lump of roughly round-shaped foam (upper left corner) is approaching the vortex funnel, and a couple of forth running ones, which were shaped similarly, but by the moment of exposure moved further into the funnel, got elongated, spaghettified and finally completely diffused in most cases, but not always, even prior to getting down to the funnel bottom. This picture reveals that it is the surface stretch, forcing the foam bubbles to leave the patch community and even burst prior to being completely transported through the vortex bottom.
Interesting phenomenon… Worth more thinking to be invested. (Yapp, done, see the addendum below).
Figure 3. Spaghettification of the floating foam patches. To watch the process in dynamics (the video) and better observe the details, start and quickly stop the video and make the demonstration speed to be the lowest possible (settings flower in the lower right corner of the screen) and then start watching from the beginning.
- Floating shredded dry leaves forming a galaxy-like shape was normally observed when a handful of them was spread over the vortex area (Fig. 4 and the video at https://www.youtube.com/watch?v=l8HBO6E8LAg).
Figure 4. Around the LV floating debris galaxy-like shape (The two bright spots are from the sky reflections and should be ignored)
The deep meaningfulness of this “seemingly looking simple”occurrence stirred my mind and I would like to share it here:
- The whirling water while flowing (naturally) into the drain guides the movement of the floating leaves. To be able of guiding, a tight intimate contact between the water and the leaves, like wetting, has to be established. In relation to the BHs (considering the upper water surface as corresponding the spacetime and the shredded leaves as the regular matter), for the spacetime to drive the matter it would require the matter and the spacetime to be also tightly engaged.
- The floating leaves were arranging in a galaxy-like shape – what drove the initially disarranged flock of intellect-less leaves to arrange in spirals? The answer is – obviously, it is the water flow guiding the leaves to follow its whirling streams. The floating leaves would never shape up in spirals if not guided by the whirling waters.
- This important deduction lead to an unambiguous conclusion: If in a system A made of a non-continuous medium a spiral or a similar structure is revealed, it must be postulated that there is an adjoined sub-system B in tight contact with A, made of continuous medium or containing a continuous medium as a basic component in which a vortex action is/was actuated (continuous medium is essential for developing a vortex, waves, whirling action etc.).
- And vice versa, if a system made of continuous medium contains a vortex or a different source generating waves or wave-like turbulence, the corresponding wavy signatures will appear in all the adjoined tightly-contacting systems.
- With reference to the galaxies, the only feature to be thought of being continuous and in tight contact with the galactic matter is the spacetime. Being actuated by the BH vortex to whirl the spacetime, while being pulled into the BH, acts as the adjoined system B.
- So, the spiral shape of the galaxies points out at the existence of a swirling continuous medium in direct contact with their regular matter. Which, seemingly, can only be the spacetime drained into the BH vortex. Swirling, the spacetime guides the galactic matter to arrange in spiral shapes.
- In both LV and BH cases the floating stuff just decorates the topography of the whirling medium it is engaged with. In the same way as criminal investigators powder the surface to visualize the fingerprints.
With regard to the considerations above, there is one more point I would like, out of my curiosity, to touch. It is of the type of the chicken-and-egg paradox, namely, what appeared first in the early history of the Big Bang – the BHs or the matter? Watching the LV, requiring nothing but liquid and gravity/drain hole to induce and sustain its being, I could not but think that the BHs creation may had nothing to do with the existence or absence of the matter at the time and place of their nucleation. As for the LV not requiring any involvement of the floating leaves to activate and sustain its action, the BH vortex nucleation also does not seem to require any matter involvement/assistance. I believe that the BH vortices could be nucleated during the early universe turbulent expansion, possibly, even prior to appearance of the barionic matter. At that time numerous turbulent spots were created over the expanding spacetime with some of them nucleating reasonably stable vortices. The nucleated vortices, generating gravitational waves, were loosing their energy and the least energetic of them have dissipated prior to the barionic fuel started to appear in quantities around. The BHs survived by this time, could continue with their being, thanks to the appeared availability of the barionic fuel.
So, it looks like the BH vortices could have been nucleated before the barionic matter appeared on the horizon. When the barionic matter appeared, the BHs, which survived by this time, attracted and consumed the matter, utilizing their swirling spacetime pull, to fuel their being, and also managed to stockpile and package some material reserves in surrounding spiral galactic arrangements.
Scrutinizing the vortex pulling-in action produced a shocking grasp
The BHs are thought of pulling/draining not only the matter but also the spacetime, whirling around as the liquid whirls around the LV. Intriguingly, this concept allows to interpret the galaxy rotation curves anomaly and the universe accelerated expansion with no necessity of introducing the two famous but still challenging to prove hypotheses:
Existence of the dark matter
The rotation anomaly can be explained as induced by the far-propagating spiral gravitational waves cumulative transfer of their angular momentum to the peripheral galaxy stars.
The halo existence could be associated with the integrated mass/energy equivalence effect (E=mc2) of the far-propagated gravitational waves. The swirling BH-centered spacetime waviness may extend far beyond the area the regular mass is observable and its integrated action may appear as an external mass halo influencing the galactic peripheral dynamics.
Existence of the dark energy
At the galactic periphery, where the BH pulling force is diminished, the keeping on centrifugal force induced by the spinning spacetime together with the cumulatively acquired radial component of the momentum from the BS spiral waves, accelerate the stars movement away from the galaxy center.
It looks like the universe background must be filled with the gravitational waves permanently emanated by numerous BHs (and other spinning compact massive objects) and propagating, essentially non-absorbed, through the space.Which actually was predicted about 100 years ago by the great Albert Einstein. Energy-carrying gravitational spiral waves, forming the rippled cosmic background, according to the equivalence principle E=mc2, should induce effects equivalent to mass, possibly, as the mysterious dark matter.
The BHs appear acting as matter-fueled power plants generating and spreading part of the acquired energy as gravitational spiral waves all over the universe. And also releasing various “fumes and slags”, as entropy co-laterally generated (The Second Law of Thermodynamics) with the matter consumption. Being of a very large wavelength and low amplitude and thereby poorly observable, these gravitational waves, accumulating, in long ran, form an energy-rich universe-wide rippling gravitational background.
The spacetime (gravitational) waves seemingly also carry some of the BH-accrued information, which, together with the gravitational energy, is transferred and disseminated on their voyage through the universe.
Again, the important points on the spacetime/matter relation:
The matter and the spacetime are adhered to each other as an inseparably engaged duo: where the spacetime there the matter. And vice versa.
The visible matter decorates the structural profile of the whirling spacetime it is engaged with… as the powder the criminal investigators use to make the fingerprints visible. The image below shows an example with the foam copying the waviness profile beneath. Also, a spaghettification development clearly appears at the image.
And at the end, a general point:
If the LV and BH show quite a number of conceptual features consistent, it would be odd to ignore it and not to consider the both phenomena to be correlated.
It is interesting how sensitive are telescope observations to the observation angle. To
illustrate what I am referring to I show two images of the LV below made under the same conditions just the left one was made under a normal (90 deg) observation angle and right one under a sharp (about 30-45 deg) angle. Please, do not pay attention at the white circle, which is the top edge of the drain tube.
The left one clearly shows the details of the funnel and its bottom and the ridge and even a bit of the waves and the right one shows the same LV pictures at a sharp observation angle. This image shows clearly the waves, however, it is impossible to see too much details about the funnel, just a section of the intensively bent ridge, and understand that the waves are actually spiral ones.
Just looked at one of the recent”scientifically guessed” image of the two coalescing BHs (see below) from a published by FURISM articles (https://futurism.com/ligo-detected-the-oldest-gravitational-waves-ever-discovered/) Well it looks so strange and conceptually very different from what I had observed with my LV. Strange indeed. Either the BH were not individually spinning or they were, but it was not accounted in the model. Imagine how the spaghettification trail will look like in such a gavitational profile.
A recently observed BH burping effect is actively discussed by the astronomers. Getting curious about it I looked into my videos and slides and also observed an effect, which could be considered as burping. Namely, from time to time, a normally calm DSW generation is interrupted by a short and violent event, producing a shooting up short sequence of intense circular waves (the corresponding image is shown below), which probably could be considered as burp.
So, apparently, the LV also sometimes “overeats” and burps. As BHs do.
Black holes draining the spacetime title statement – does it indeed sound that crazy? Maybe not if considering the following.
If a hole, a BH, is created, and grows, it must stretch and pull the spacetime, as a rubber film,”down” into the depth of its singularity, actually meaning that
The spacetime really must flow into growing BHs. The more mass acquired the fatter the BH and the more spacetime pulled (flows) in.
How and when all this scenario was developed? I believe it all started some time around the end of the inflation phase when the quickly expanding universe was started to be filled with the fog of freshly formed barionic matter. And certainly, engaged with it spacetime was certainly there, though not yet formally introduced by Albert Einstein.
And it all was violently expanding…
The turbulent expansion of a continuous medium, the spacetime, is naturally associated with formation of a variety of dynamic non-uniformities. Turbulence is known to normally being characterized by some significant vorticity activity.
To sustain turbulent flow, a persistent supply of energy is required. Thereby most of turbulences were dissipated while being stretched, except those lucky to have around enough barionic matter to acquire helping vortex compensate for stretching by getting deeper.
The increased depth of the spacetime dip helped to attract more matter from the surrounding, which, in its turn boosted its deepening, and so on.
Continuous increase in the dip depth associated with the spacetime flow into it at some acquisition rate developed a rotational momentum becoming a self-sustaining vortex. The vortex induced spacetime whirling and spiraling over the extended area around aggressively pulling in the matter, probably, even faster than being static gravity governed, ultimately nucleating a black hole.
So, the quickly increasing mass intake stimulated quick increase in the spacetime dip depth and the spacetime flow rate into it. At some point a black hole is developed, assisting even faster acquisition of the matter from the larger area around, thanks to the spacetime spiraling motion.
However, the spiraling black hole will generate spiral waves, which will cost it energy. It, nevertheless, will still continue to grow until there is enough matter around to compensate for the energy losses. But good times tend to end – at some point the mass resources around are exhausted and the BH singularity starts to shrink spreading over the universe the energy and the information acquired until it finally completely “evaporates”. I guess, a number of dying “naked” stray BHs are going to be observed thanks to the effect of the gravitational lensing they induce.
And once again about the spacetime-matter engagement, critically important in this scenario – as it was stated above,
The spacetime and the matter are linked to each other as non-separably engaged duo – where the spacetime there the matter. And vice versa.
Amazing, how far your mind can take you while observing just a water drain vortex in a water-park pond!
Promise is promise… to continue with the discussion on the Spaghettification matter
I would name this section as
Fragmentation, ripping, crashing, disintegration…
Let me turn you back to the image and video I introduced above
To remind you, this image shows is a snapshot of a floating foam pulling into the LV funnel, demonstrating various phases of the spaghetification sequence, namely, a chunk of foam approaching the funnel (upper left corner), a smaller chunk started to elongate at the front and also rear side, and two strings in the front side of the image, which propagated further into the funnel and are spaghettified already in a significant extent. To watch the process in dynamics (the video) and better observe the details, start and quickly stop the video and make the demonstration speed to be the lowest possible (settings flower in the lower right corner of the screen) and then start watching from the beginning.
Reading reports about interpretations of some developments in the galaxy centers, many of which are semi-empirically interpreted based on sequence of events a BH swallowing large chunks of matter, like stars or star systems, I decided to summarize the features of major structural developments occurring in an event when a large foam system is pulled in and swallowed by the LV. The set of associated images and my comments on the occurrences are given below.
The set of six images above presents various top and side views of the funnel and the area around it, showing various details of spaghettification, such as large foam patches just approaching the funnel, and elongated strings almost drowned down into the funnel, and “spaghettified” foam spiraling down to the funnel bottom.
The several side view images are also presented to make the spaghettification dynamics better visible, which follows a well-repeatable size-reduction sequence, formulated in the headline of this comment as fragmentation, ripping, crashing, disintegration…
Watching the numerous and very repeatable LV spaghettification events and then reading some published theoretical speculations on these matters, I frequently think that scientists better watch how the LV is doing it and how a spaghettification trace looks like. It would be a great assistance for the models they carry out to appear more reasonable.
Wow, it just appeared (6/14/17) at the Web from NASA: “Now, thanks to an artistic rendering made available by NASA, you don’t have to leave much to imagination… watch a star stray a little too close to a black hole and get shredded apart by “tidal disruptions,” causing some stellar debris to get “flung outward at high speed while the rest falls toward the black hole”
Amaizing, how similar are the expected cosmic developments as compared to those at the LV.
I believe it is important to keep it in mind while discussing the observables and the associated developments taking place in the galactic space, such as, for example intense radiation splashes in different intervals of the EM spectrum. If a similar sequence takes place with a large cosmic object, say, big star, for example, or a tight cluster of stars, it will be fragmented into a large number of smaller fragments, and the energy emitted will be in a reasonably mild spectral interval. Then a more intense ripping process will take place when the fragments formed enter into a harsher gravitational force melting and crashing the hardest formations into dense and compact atomic/molecular elongated clouds, which later will be disintegrated into subatomic species and more densified forming, probably, a neutron made phase, solid or liquid, and later into… who knows. And the energy released along this pass will start with rare mild energy splashes, gradually transforming into frequent higher energy pulses and at the end permanently occurring high frequency emissions until it deems out.
Well, I was glad to observe that astronomers are also starting to use terms “as ripples in the pond” while discussing the “fuzzy” dark matter matters. I am sure sooner or later they will need to consider in their models the BH DSW generation. One major complication here might be associated with the point that at the funnel nearby vicinity the warping picture is messed due to contribution of low amplitude phase shifted waves (see the images below), which quickly dissipate leaving only the DSW propagating at larger distances from the LV.
- Phase shifted low amplitude spiral wave satellites, which most probably are associated with the spinning bottom small scale distortion features, which act in the same way as the main modulation digit 8 shape . May these satellites be considered as an echo effect? I guess, in a way, they may.
Phase shifted satellites are probably associated with spinning small scale bottom distortion features.
Well, here is another pretty fresh consideration, which, to my opinion deserves attention. Thinking about the BH shape state, I guessed that, assuming the BH is not an absolutely rigid formation, its shape should experience kind of convulsive instability. To see how these convulsive shape fluctuations may perturb/modulate the nearby spacetime fabric, I ran a simple (very simple) approximation of the cumulative amplitude fluctuation by summarizing 2 dozen of cosine waves (assuming symmetrical vibrations) linearly varying their frequencies (see the lower graph). I estimated the parameter for the distance dependence of the amplitude decay to be 1/d^2 and I turned the final profile into negative space by multiplying it by -1 to make it resembling the BH.
The graphs shown below (the cumulative spectrum and individual contributions) together with the upper graph of the ultimate cumulative multi-vibration modulation profile of the spacetime fabric exited me greatly. The two inserts of the upper chart show two results with very different frequency discretisation sets, both showing similar profiles structure, namely
The approximation shows a clear bulge to appear around the BH funnel, which is clearly observable with the LV (see the images below), and
a distinct gravitational minimum, a circular ditch, outside the bulge, which, I think, if existing in reality, can collect and retain the scattered matter (I mean, regular matter, not dark matter) .
I checked about a half-dozen of different frequency discretizations sets and the result was qualitatively the same, namely, the bulge and the surrounding it ditch, always appeared around the BH funnel.
So, the conclusion on this is:
If the BH are not rigid formations then, due to their inevitable vibrational shape instability and associated spacetime perturbation, a bulge and a gravitational ditch, capable to collect the regular matter, next to it are likely to appear.
Existence of bulge was already observed for some BHs. Most probably, indicating that a gravitational ditch, surrounding it and collecting the regular matter, also exists.
Acting as a gravitational halo…
Aha, consider resonance irradiation amplification, observed in http://www.zmescience.com/science/simulating-black-hole-bath-tub/ – “We observed that waves propagating on the surface of water can be amplified after being scattered by a draining vortex. The maximum amplification measured was 14% ± 8%, obtained for 3.70 Hz waves, in a 6.25-cm-deep fluid, consistent with the superradiant scattering caused by rapid rotation. We expect our experimental findings to be relevant to black-hole physics, since shallow water waves scattering on a draining fluid constitute an analogue of a black hole, as well as to hydrodynamics, due to the close relation to over-reflection instabilities,” The observation is in agreement with the vortex shape multi-frequency vibrations, simply explained by resonant amplification of the excitation inducing wave. Aha, consider resonance irradiation amplification, observed in http://www.zmescience.com/science/simulating-black-hole-bath-tub/ – “We observed that waves propagating on the surface of water can be amplified after being scattered by a draining vortex. The maximum amplification measured was 14% ± 8%, obtained for 3.70 Hz waves, in a 6.25-cm-deep fluid, consistent with the superradiant scattering caused by rapid rotation. We expect our experimental findings to be relevant to black-hole physics, since shallow water waves scattering on a draining fluid constitute an analogue of a black hole, as well as to hydrodynamics, due to the close relation to over-reflection instabilities,” The observation is in agreement with the vortex shape multi-frequency vibrations, simply explained by resonant amplification of the excitation inducing wave. All wrong! Rotational and vibrational interactions should not be messed in one picture. Additionally to this, I am not sure the superradiance stuff presented by the authors of the work cited above is really correct. I feel a kind of over-speculation is hidden there.
I believe, it would be important, and even necessary, for the authors to show the individual values of Aout and Ain prior to combining them to calculate the value of the reflection coefficient, R = Aout – Ain. It would be very logical to have a look at and check the details of the Aout and Ain variation dynamics to see how it resulted in the R >1 effect. I would find myself completely “entangled” if figuring out by the end of the day that the (R>1) superradiance effect was the result of the suppressed incoming energy flux rather than of the amplified outgoing one – kind of amplification by suppression phenomenon. Considering the observed damping effect at f > 3Hz I suspect it might be the case.
It sounded pretty interesting to me, so I decided to look through my recorded video clips to check if these matters somehow appear there. Well, it is always worth to give another look. And here below are shown my findings.
It looks like YES there is a bulge surrounding the funnel and, most probably, a halo next to it.
I was excited to see that the surface topography, surrounding the funnel, acts as an optical reflection lensing, as in the case of the cosmic BHs. Below, I show a selection of 5 images appeared at different moments of time and also a top view of the surface around the LV demonstrating the mentioned lensing effect.
The dotted blue line shows how a reflection of a straight object (a column at the bank) would look like in case the water surface was flat, and the red line and the yellow dotted lines are plotted via the actual reflections as they appear on the tops of the waves. Yes, details matter a lot!
Thank you for your attention
Addendum (requiring future attention) – Fine structural elements observed:
- In-between-the-spiral-arms sectioning, seemingly associated with vorticity developing due to the shear caused by the spiral wave geometry .
Sectioning- spiral wave imposed shear induced between-the-arms associated vorticity.