Response to Paolo Di Lazzaro’s theorising (unfinished business from February) under the title: “Colin Berry’s idea is untenable, and heat cannot produce a superficial coloration”.
PDL: “Let’s approach the basic elementary physics that explain why the idea of Berry is untenable, and heat cannot produce a superficial coloration.”. The hot metal transfers energy (heat) to the primary cell wall (pcw) of the linen fibrils by contact.
Yes, and that energy produces a chemical reaction called scorching in that same superficial layer. Are you going to mention that or not as a DIRECT, IMMEDIATE and LOCALISED effect of CONDUCTED heat? Watch carefully what happens next, dear reader.
PDL: From a microscopic view, transferring energy by contact means the hot (i.e. fastly moving) atoms of metal hit hemicelluloses molecules transferring momentum, thus increasing both amplitude and velocity of the motion of hemicellulose molecules around the equilibrium position (centroid). As a consequence, hemicellulose increases its temperature.
Correct. The hemicelluloses in the primary cell wall are heated. So we now expect to see the series of chemical reactions that collectively are described as pyrolysis or SCORCHING. Do we?
PDL: In the regions of contact between pcw and cellulosic medulla, we still have a transfer of heat by contact, like in the previous metal-pcw case. The temperature of the medulla will increase.
But you are now tracking heat into the deeper layers, like the medulla (centre) of each fibre, which incidentally is hollow (it’s the surrounding annular wall that is cellulose). You have not said what the heat did to the first-encountered PCW. Are you not running away from that first point of contact. Are you seriously suggesting that heat from hot metal is simply conducted through the PCW as if it were copper wire? How can you expect anyone to take you seriously if you are evasive or in denial on so crucial an issue?
PDL: In the region where there is no contact (e.g.,a small air gap between pcw and medulla) we have heat transfer by irradiation.
You are still running away from the crucial issue – the effect that the conducted atom-to-atom heat has on the primary cell wall (PCW).
PDL: In fact, every material emits radiation having a spectrum peaked at a wavelength which depends on its temperature: the higher the temperature, the shorter the wavelength. This is the well known phenomenon of the black body emission, governed by Planck’s law, Wien’s law and so on (first year exam for students of Physics, Mathematics, Chemistry, Engineer).
Ignoring the final jibe (which says a lot about you) we can discuss secondary effects, if any, of radiated heat another day. For the moment, let’s stick to discussing the effect of that CONDUCTED heat on the PCW.
PDL: As an example, at 20 °C the walls of a room emit radiation with a broad spectrum, peaked in the far infrared at about 10-micrometers wavelength. In the case of hemicelluloses at 200 °C the pcw emits infrared radiation peaked at 6,1 micrometers.
Yes, but this is all at best secondary, or at worst irrelevant to the effect of CONDUCTED heat on the PCW.
PDL: In the case we are considering, the 6-micrometer wavelength will interact with the cellulose of the core of the linen fibril (medulla), exciting vibrational levels of cellulose that decay in heat thus increasing the temperature of the medulla.
You have switched from discussing primary CONDUCTED heat to secondary radiated heat. What’s more you have shifted the discussion from the superficial PCW to the deeper medulla, omitting to mention that the PCW is the first plane to become scorched, and scorched moreover by CONDUCTED heat,
PDL: In addition, a well known optics law tells us the penetration depth of the interaction between radiation and medulla cannot be smaller than the wavelength, that is, not smaller than 6 micrometers in this case.
Why this concern for the secondary effects of radiated heat on the inner layers, weak by contrast with atomic mass/momentum- aided conduction? It is the effect of PRIMARY CONDUCTED HEAT on the SUPERFICIAL PCW that is, or should be, of immediate and primary concern.
PDL: This fact alone explain why infrared radiation cannot produce a superficial coloration of fibers.
But we are not discussing infrared radiation, my dear chap. I have not mentioned it, except in my very first posting on the Shroud of Turin, back in Dec 2011, if only to point out that infrared will not scorch white linen unless a dark absorbing pigment is present, to give what I called a thermo-stencilling effect, with non-coated linen being unscorched. What’s more, your experiments did not discuss infrared. You went straight for uv radiation – based presumably on the flawed reasoning provided above that attempts to airbrush conduction out of the picture, substituting secondary radiation for no good reason, except as a sleight-of-hand. So why are you bringing in infrared? It is a complete red herring, or should that be infrared herring?
PDL: By the way, it is not possible that “the resistant cellulose cores that are unaffected are able to conduct away heat rapidly” (see above Berry’s statement) because of elementary fluid dynamic equations (a classical engineering problem), of a not convenient area/volume ratio of cylinders (elementary geometry) and because Berry assumes a exothermic pyrolysis of cellulose, that is,by definition, a runaway process, extended in time.
“Berry assumes an exothermic pyrolysis of cellulose” ? Show me where I said that. This Berry has assumed no such thing. In fact his most highly visited paper – with some 800 hits to date – explores the consequences at the fibre level of the reported exothermic pyrolysis of HEMICELLULOSE, proposing that it could account for the half-tone and other subtle characteristics of the Shroud image. What’s more, he stated clearly that cellulose pyrolysis is ENDOTHERMIC, not exothermic, which you referred to in your preamble, citing numerical data from his literature search, not yours. But all that is by the way. You have simple evaded the real issue, and virtually all that paragraph above is pure flannel.
PDL: In summary, when heating a linen cloth by a hot metal in contact, well known physics models foresee the pyrolysis of the whole fibers and threads, and this is exactly what we observe in the experiments.
Your “well known physics models” are phoney models, ones that would have the gullible or impressionable reader believe that the energy in conducted heat is converted to radiant heat without affecting the carbohydrates in IMMEDIATE contact with the metal. Your claimed pyrolysis of whole threads is based on entirely bogus reasoning, yet in the six months that screed of yours above has been displayed on Dan Porter’s blog, no one (apart from myself) has pointed out the spurious nature of your reasoning, or the false premises upon which your recourse to high energy radiation – laser-generated uv no less – is based . Nor has anyone supported me against the attacks you have made on my conclusions, ones that are based on a REALISTIC source of thermal energy underpinned with sound scientific theory. So there is much that is seriously wrong with your science, and much too that is wrong with the Porter site that is used as a portal for the kind of disinformation that you and others promulgate in the name of science.
Virtually everything you have written is what I have previously described as Mickey Mouse science. Rest assured that I shall continue to describe it as such for as long as you continue to ignore or trash fundamental physical and chemical principles in the way that you do, purely to justify your wacky (and no doubt agenda-driven) line of research with laser beams.
PDL: Useless to say, it is all the approach of Colin Berry to find a middle age technology able to create the Shroud image that is hopeless: just consider the half tone effect. It could not have been made by medieval forgers because they would need a modern microscope to observe and then control their micrometric-scale coloration.
That too is Mickey Mouse – albeit in a comedic sense. As mentioned earlier I have already proposed an explanation for the curious half-tone effect. To the best of my knowledge, nobody else has done so. Maybe that’s why my hemicellulose posting has had those 800 or so hits, with new ones arriving each day, 6 months after it was posted.
As for your contribution to Shroud studies, exemplified by the flawed theorising above, used to justify those absurd laser beam experiments, there is an analogy that springs to mind.
Imagine one is watching a live report on TV from a hovering helicopter: a tsunami has engulfed a coastal community, creating a swathe of destruction along the shoreline. What’s one’s reaction if the commentator then says: “But the town has not completely absorbed the energy of the wave. It still has energy and is now moving inland, no doubt to wreak still more havoc. So let’s not dwell on the initial impact, folks, with all its fearsome details like the widespread death and destruction that I see beneath me. Let’s focus instead on what happens next with that weakened wave now coursing into the hinterland. Think what it will do to the crops, the forests, the roads? It’s simply too awful to contemplate, but contemplate we must – as the top priority… We’ll leave it to others on the ground to report what’s happening in the town below.”
That, in a nutshell, is the gist of Paolo’s argument. In short, he is displaying a monumental blind spot to the immediate and HIGHLY LOCALISED effects of conducted heat on the superficial fibres of linen, and indeed the superficial component of those fibres, namely the PCWs, and instead, ignoring all of that and focusing on downstream and (probably) largely inconsequential effects.
Accidental or deliberate oversight? I leave that to readers to decide… Either way, it is MICKEY MOUSE SCIENCE.
Afterthought (added 24 Sep):
Di Lazzaro’s position, succinctly stated: “Never mind the primary effect of conducted heat on the superficial layers. What about my (largely theorised) secondary effects on the cores of the fibres”
My answer: we need to prioritise. The first concern is with the mechanism that produces the superficial image (and I know scorching is superficial at the level of threads and fibres within those threads, only a few of the latter in each ‘bundle’ being scorched). I say that mechanism is immediate contact with a hot surface, e.g. metal, or more likely plaster or ceramic. That speaks of a thermal imprinting procedure, akin to branding of rawhide with hot metal. It sees no role whatever for radiation ‘at a distance’. If there is the slightest air gap, then there is essentially no imaging (contrary to those who claim without compelling evidence that there is imaging on the Shroud where sizeable gaps of up to 4cm between cloth and body are hypothesized).
To reject conduction on the hypothesised grounds of what secondary radiated heat will, or rather MIGHT just do to the cellulosic cores of fibres, is not just unhelpful but perverse. Why? Because commonsense alone tells one that a surface scorch acquired by direct contact with a hot object can be as faint or as superficial as one wishes. Everyday experience confirms that (brushing against a hot oven door may be painful but does not produce a deep third degree burn). Scientifically, that commonsense assumption is rationalised by saying that the intensity of a scorch is a function of variables that are continuous and independent, like temperature, time and contact pressure. If an experimentally-produced scorch is considered too intense, or not sufficiently superficial, it can be made fainter and more superficial simply by reducing temperature, time or pressure in a controlled and systematic fashion. There is no ‘all-or-nothing’ effect.
Yes, it is an easy matter to produce an intense scorch, as Paolo did by choosing a particular temperature that was 10 degrees higher than the reported pyrolysis temperature of the hemicelluloses, and then keeping the metal pressed against the linen until the desired outcome -a deep scorch – was produced. But that is cookery, not science. (ie. not so much an open-ended experiment, more a contrived result, with the supporting “theory” being added as a topping). As I and others commented in the original posting, back in February, he should have investigated lower temperatures, with a view to producing fainter scorches that are progressively more superficial. In so doing, he would have falsified his own non-intuitive hypothesis, namely that a scorch can never be superficial. In fact he could not be bothered to respond to my critique or that of others on that thread, which is why I decided to pursue the matter no further on Porter’s site, and why, 6 months after the event, the second instalment to my response finally appears here. Let Dan Porter, no stranger to ad hominem name-calling himself, fume all he likes about my “Mickey Mouse” label, but if he observes closely, it is directed at the science, not the individual.
Finally, to those who have demonstrated their staying power by reaching this point, have you seen my recent post, listing some 20 reasons for thinking that the Shroud’s body image is simply a thermal imprint (with no grounds at present for thinking that contact-conduction scorches can never match the claimed superficiality of the Shroud’s image)?
Responses from The Other Site, that for once has done a cover version without the customary negative spin (thank you Dan):
Di Lazzaro’s results? What results? A small brown discoloured patch on linen that has been blitzed with pulsed uv radiation from a vacuum excimer laser? Reminder: the energy of uv radiation approximates to that of covalent chemical bonds with shared pairs of electrons, such as exist in carbohydrates, so it is hardly surprising that uv will produce slight scorching on linen, for the same reasons it will give sunburn or a suntan on human skin. But where was the source of uv for leaving scorch marks on the Shroud, far less entire reasonably sharp images (with negative character, encoded 3D information etc)? Answers on a postcard please…
It’s not about PDL’s somewhat unsurprising results that fail to explain the Shroud image, except maybe in terms of extreme superficiality (although without providing credible supporting evidence for his rash claim that a thermal scorch cannot be every bit as superficial if you select the right conditions in terms of temperature, contact time etc). It’s about his recourse to high energy radiation, based on an unfounded premise that a conduction scorch can never be superficial. That premise is wrong. It is wrong on theoretical grounds. It is wrong on commonsense grounds, and I suspect it will ultimately be proved wrong on experimental grounds too, once the technology is available for measuring the thickness of superficial scorches on linen (see tongue-in-cheek post immediately preceding this one).
Late addition – 26 September – after brushing up on my radiation physics:
As soon as anyone invokes black body radiative exchange in real-life situations that involve short-term interventions or disturbances of one kind or another, then, 9 times out of 10, you can be sure the physical principles will be misapplied. Why? Because it applies to systems in thermodynamic equilibrium, or at a push those that, if not in equilibrium, have achieved some kind of steady state. But that is not the case when you suddenly bring together hot and cold bodies within close range of each other. It may take a considerable time for that system to reach equilibrium. The very name “black body” radiation explains why. A black body radiator is one that absorbs all radiation that it receives, so that all of the radiation that it emits is by emission. In practice, there are no perfect black body absorbers/radiators. Many materials are reflectors rather than absorbers – linen being a case in point. Only a small proportion of infrared radiation that falls on linen will be absorbed – most being scattered/reflected. Yes, that linen would finally come to thermodynamic equilibrium because of the small proportion that IS absorbed, gradually, very gradually absorbing nett energy from the nearby hotter object, and continuing to exchange after equilibrium has been reached, but IMPORTANTLY, not experiencing any sharp temperature rise prior to equilibrium on account of its continuing to reflect most of the incident radiation from the hotter body. All that changes once the linen is coated with an opaque absorbing material – like the charcoal I used in my own initial experiments when exploring (and quickly rejecting) radiation as the mechanism by which the Shroud acquired its superficial image.