Light bulb Experiments: Slaying Watts with Watts

Anthony Watts has performed an experiment in follow-up to Roy Spencer’s challenge to the Slayers/Principia Scientific International to “put up or shut up”, to which we replied that we had already put up, and in which we proved that Dr. Spencer’s understanding of the offered challenge was somewhat lacking. Curt Wilson has also done a follow-up experiment for WUWT.

Unfortunately, our successful answer to the original challenge was ignored and a new line of questioning was instead pursued by Watts et al. Sometimes this is called changing reference frames. The distraction comes from a diagram we used to present a general physical principle of thermodynamics, such that radiant emission from a source cannot act as an additional source, for the source. This means that the source cannot become brighter, which in radiative emission terms of the Stefan-Boltzmann Law means hotter, from its own radiation. If such a thing could happen, then an object’s own radiation could act as a source or cause of temperature increase for the object, which is of course plainly in violation of thermodynamics.

The diagram which has presented the hapless convenience for Watts et al. to reframe the rebuttal to their challenge, is reproduced below:

Siddons Light Bulb and Mirror

Figure 1: (Image courtesy of Alan Siddons.)

This diagram (Figure 1) was included in the context of a previous diagram, as shown here:

Siddons Two Light Bulbs

Figure 2:  (Image courtesy of Alan Siddons.)

The point of the discussion surrounding these diagrams was in terms of an elucidation of the underlying physical principles which govern the fundamental thermodynamic behaviour. Unfortunately, the underlying physical principles of thermodynamics, such that a source of light cannot make itself shine brighter (i.e. become hotter) with its own light, or that two equal sources of light cannot make each other brighter (hotter at the source), can be ignored at the expense of mischaracterizing an experiment to test them. It would have been just as well if Watts et al. would have chosen to create an experiment based on Figure 2, because the brightness results would have been much more obvious. However, Figure 1 and Figure 2 do allow for significant misperception if the underlying principles are not understood, or ignored. This is something we didn’t consider would occur, and it is an important lesson for science communicators.

Regarding the underlying theoretical principles of what such an experiments requires to be understood and in regards to the greenhouse effect, Mr. Watts replied at his site: “And yet, in the diagram proposed in the essay by Postma, such fine details were not mentioned nor required. Demanding them now post facto doesn’t fly.”

Unfortunately, expecting the “fine details” to be appreciated is something we expected a-priori. That was our mistake. Unfortunately, it is the onus of the experimentalist to be competent and responsible for their complete understanding of what it is they’ll be intending to measure, and to quantify it. If all of the details aren’t sorted out, such as what the underlying physical principles are, as opposed to a simple literal interpretation of words without context and misidentifying original causes, then any such discussion by the experimentalist of the empirical results cannot be expected to be meaningful. It has always been a tricky business.

The underlying physical principles we had expected to be understood can be expressed in terms of the general equivalence of concepts between three major areas of physics: force mechanics, electrical mechanics, and thermal mechanics. It is sometimes helpful for a student to consider that a problem in one domain can be qualitatively solved equivalently in another domain, for example: voltage is like temperature is like force; current is like heat flow is like acceleration; and electrical resistance is like thermal mass is like material mass.

Postma domain table

In terms of an energy analysis, force, voltage, and temperature all represent the potential to induce action if there is a non-zero differential in them. That is, a force differential causes acceleration, modulated by a physical parameter; a voltage differential causes current, modulated by a physical parameter; and a temperature differential causes heat flow, modulated by a physical parameter. In all cases the nature of the action is similar: the acceleration caused by the force does not increase the force; the current caused by the voltage does not increase the voltage; and the heat flow caused by a temperature differential does not increase the temperature. In all cases, if one wishes to modify the action, they must either modify the differential, or modify the relevant physical parameters. We will see ahead the importance of these facts.

In an electrical circuit, dissipation of energy is performed by the resistor. The energy dissipation takes the form of heat in the resistor, and if the physical parameters of the resistor and the circuit are appropriate, the resistor can become hot enough to emit visible light. Typically, light bulb filaments run at 3300K and produce emission close to a blackbody. It is important to comprehend that the source of the thermal emission/heat generation in the resistor is caused by the current running through it, and the current is caused by the voltage applied to the circuit. If the filament emits similar to a blackbody, then its radiant output flux density can be related to the Stefan-Boltzmann equation. The radiant emission has as its source, then, the current going through the circuit, which is caused by the voltage applied to the circuit. If you want to increase the temperature of the source of light/heat so that you can produce more light/heat, and the source of those is the filament, then you have to increase the current going through the filament, and this is done by increasing the voltage across the circuit. It cannot be done by giving the filament the light or heat it produces back to itself, as the light is dissipated energy, not source energy for the circuit or filament. The filament’s dissipated energy cannot be used to increase the voltage across the circuit, and hence cannot be used to increase the brightness/temperature of the source.

Both of the WUWT experiments make the mistake of considering that the frosted glass of the bulb is the source of light and heat. PSI acknowledges that such a confusion is possible if you look naively at the diagrams and see what looks like a frosted bulb and simple-mindedly assume that the frosted glass itself is the source of the energy, and assume a bland interpretation of the words describing the scenario.

The frosted glass is a source of light in as much as it scatters the incoming spectrum, and it is a source of heat in as much as its absorbs the incoming spectrum. Obviously, the actual source of light and heat is the filament inside the bulb producing the spectrum at a typical temperature of 3300K, and the source of energy for the filament is the voltage applied to the circuit. The frosted glass is a passive semitransparent screen in front of the actual source. The frosted glass bulb itself, once heated, can be a source of heat for something cooler than it, such as a finger or hand, but it is not the source of energy.

We did not expect that the underlying physical principles would be disregarded, or plainly not understood, nor scientifically quantified. This experiment could be repeated to check for a brightness increase of the frosted glass when another bulb is brought nearby; this might actually occur, but the reason would be that the frosted glass has a high albedo and some additional light would simply be reflected back. Again, this would not actually get down to the underlying physical thermodynamic principle involved nor of what is claimed with the greenhouse effect, because the true source wouldn’t actually increase in temperature. Mr. Watts has insisted that we do not consider such fundamentals of theory and its quantification and instead focus only on the surface appearances of his experiment; doing such a thing obviously presents the opportunity for obfuscation, and we can wonder if this is intended, or simply not comprehended.

It becomes clear that it is the frosted glass of the bulb which presents the confusion regarding what is the actual source of light and heat. The opacity of the glass provides a convenient occlusion of the underlying physics. We may not be able to see inside the frosted glass bulb, but nevertheless inside the frosted glass bulb is a filament at 3300K. Indeed, this experiment would have been more obviously nonsensical if a clear glass bulb was used, because clear glass exposes the underlying source of things. Indeed such details were not discussed by us there, but we would have expected an honest experimental assessment of the true underlying physics of the fundamental concept we described, rather than this more haphazard and amateurish assessment.

To be sure, the source of this light bulb experiment is a convenient bait-and-switch away from the fact that we answered Mr. Watts’ and Roy Spencer’s challenge to us, in which we demonstrated that they did not understand their own challenge, in which we had already answered their challenge, and in which we proved that it is possible to scientifically quantify with theory and with empirical data that the Earth is spherical, that sunshine is hot, and that no greenhouse effect exists. Is it a bait-and-switch we provided the opportunity for? Yes that can be said. However, such a response was only possible in a crass environment.

The results of this experiment go back to the original challenge from Watts & Spencer, and relates directly to the confusion related to the greenhouse effect. In the greenhouse effect, it is the source input which must be added to by its own reaction in the system. Both Mr. Watts and Mr. Wilson stated that their experiments showed that the heat produced by the bulb was able to come back and heat the bulb up some more. This is the same thing as saying that the light and heat produced by the circuit was able to come back and add to the voltage applied to the circuit, which is obviously nonsensical, but these are the details Mr. Watts would like to ignore.

The question ultimately goes back to the source, and what is causing the actual light and heat. In the case of the circuit, it has just been discussed – the voltage applied to the circuit, the current through the circuit, and the electrical energy dissipation in the filament. In the case of the models which create the greenhouse effect, it is the globally-diluted sunshine which is modeled at a forcing temperature of -180C, or 240 W/m2. What is required by these models, because they use a value of sunshine which is far colder than its actual value, effectively treating the Sun as if it twice as far away from the Earth as it is, is to have this forcing input become increased to a higher temperature by having the atmosphere, which is heated by that diluted solar input, send back some thermal radiation to have it augment the input heating. This is why Mr. Watts and Mr. Wilson interpreted their experiments in the way that they did and stated what they stated about them. Watts: “…I have just proven in the “simplest” mirror experiment…that some energy will be returned [causing more heating]”. Wilson: “We therefore have solid experimental evidence that radiation from a cooler object (the shell) can increase the temperature of a warmer object”.

Typically this is called backradiation heating and has been the traditional mode of explanation and argument for the greenhouse effect, although within the greenhouse effect following itself there is typically little consistency. For example, Watts: “I’ve never made a doubling claim …, nor am I aware that any of the others named have claimed a doubling”. However, this PSI paper (Appendix H) lists as references twenty-five major institutions that adhere to the flux-doubling back-radiation heating argument of the greenhouse effect. It matters little whether one is claiming an exact doubling, a 50{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117} return, or whatever, for it is the underlying concept which is the heart of the engine, such subtle details which are important to understand. But for example, a full doubling of the input is exactly what we see from the University of Washington’s Department of Atmospheric Sciences, in Figure 3. It is important to note that the actual input in these greenhouse effect diagrams is a forcing of -180C or 240 W/m2, which is a Sun twice as far away from the Earth as it actually is. What is then done is to have the dissipated response heat from this input come back and add to the input again. (Although little consistency will be found within greenhouse effect advocacy because sometimes it is argued that the backradiation simply slows cooling instead of actually causing heating, among other alternative claims…this lack of consistency indicates a severe problem at the core of the theory, which has been discussed elsewhere.) In the greenhouse effect models such as Figure 3, the input forcing is augmented by its own reaction in the system, causing further action within itself, bumping the forcing temperature up to 303K. This inbred process is called “the greenhouse effect”, and it is required because the model places the Sun twice as far away as it should be. It is a plain violation of reality, and then of thermodynamics. If a real-time physical model is used instead with the actual Sun and spherical Earth, as PSI demonstrated, then perhaps not-too remarkably, the input forcing is naturally 303K. The standard models create a fiction of the Earth and Sun in order to create a greenhouse effect meme to fills the gaps between reality and fiction, whereas a natural model produces the same results without any additions. In the natural model published by PSI, for example, it is the Sun which creates clouds and drives the climate by its real-time action in the system; in the fiction models, the Sun cannot create clouds. The preference between the two should be obvious.

standard Greenhouse Gas Model

Figure 3: Solar radiation is diluted to an input one-quarter of its actual power density in order to create the greenhouse effect. This effectively makes the Sun twice as far away as it actually is. (http://www.atmos.washington.edu/2002Q4/211/notes_greenhouse.html)

For an electrical resistive circuit such as that for an incandescent light bulb, the power being utilized by the circuit is that which is put into it, via the voltage and the current that is then generated. (In practice the inrush current takes a short time to stabilize but relatively quickly a stable resistor temperature and current is reached.) The equation for the power is P = I2R = V2/R, and has units of Joules per second, or Watts. If you can determine the surface area that this Wattage interacts with, you can then connect it directly to the Stefan-Boltzmann Law, F = σT4. If A is the surface area from which the power is being emitted by the filament, then F = σT4 = P/A = I2R/A, and so T = (I2R/σA)1/4 . So, the temperature of the filament, which is the source of the light and heat, is caused by the current in combination with the other physical parameters of the filament, as we discussed previously. In terms of the radiant source itself, if we wish to produce a higher source temperature and hence higher brightness and more heat, then we must increase the current through the circuit. This can be done by increasing the voltage because we can replace the current term with voltage from the previous equation, that is, T = (V2/σAR)1/4 . Directing the radiant output from the filament back on to the filament does not increase the voltage across the circuit, and hence does not cause an increase in brightness of the source. Such a scheme is a basic violation of the set of laws of thermodynamics let alone the basic physics of the process, because we cannot use the dissipated heat energy from a process to do more work (increase the power) in that process. Such heat produced can only go do work (such as raising temperature) on something less energetic than it.

WUWT bulb experiment

Figure 4: Schematic of the WUWT experiments.

In Mr. Watts’ first experiment, the power rating of the light bulb is listed at 65 Watts. This is partially absorbed by the passive frosted glass bulb. Roughly, his lamp bulb had a diameter of 10cm and is approximately flat, and so, if the power were fully absorbed, this would result in a temperature of about 6200F. At the start of his experiment without the mirror, Mr. Watts recorded a frosted glass temperature of only 2100F, which indicates a glass absorptivity of about 13.1{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}. After he added the mirror it went to 2280F, which is marginal increase to 14.6{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117} absorption. This result is rather obviously explained in that the mirror simply returned some of the non-absorbed, transmitted light, which passed through the frosted glass the first time, and then some of this would be absorbed on the second encounter with the frosted glass again. This is not heat coming back raising the temperature of the source, this is source energy having another go at absorption in a secondary passive element. There may have also been some convective reduction in the vicinity. There is no source being heated by its own radiation, but a passive screen being heated more efficiently by creating a partial cavity in its environment. Again, the source temperature is given by the power input to the circuit, not by the energy dissipation of the source adding to the source temperature.

In Mr. Wilson’s second experiment, the power usage of the bulb was recorded at 35 Watts. In this case the bulb glass is roughly spherical and a typical bulb of this sort has a radius of about 3cm. At full absorptivity, the glass would have a temperature of 226.60C. Without a cover, the glass had a temperature of 950C, which indicates an absorptivity of about 33.6{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}. The best case scenario of this experiment was with the bulb covered by the reflective foil shell, with essentially identical results being found whether the shell was by itself or covered on the outside with glass; the temperature of the frosted glass of the bulb was 1770C. With much higher inner reflectivity and a more complete creation of a cavity than the first experiment, the transmitted light from the source is presented many more opportunities for interacting with the glass bulb, with this scenario indicating a total of 75.2{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117} of the power being produced by the source being absorbed by the glass. Again, the source temperature is given by the power input to the circuit, not by the energy dissipation of the source temperature adding back to the source temperature. The energy dissipation from the filament cannot increase the power being applied to the circuit via the voltage. The difference between the glass-only vs. black-anodized box is simply that the black box absorbs more energy and so this will allow a higher temperature inside the box to be achieved than if the radiation is mostly transmitted through the box without much absorption, together with the convective trapping occurring. The black box gets to a temperature of 470C, and if its emissivity is approximately 98{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, then if the box were a cube it would have a side-length of about 11cm, which is very close to what is seen. There is nothing unexpected occurring here either. The highest shell temperature is with aluminum foil, with the foil either covering the glass container, or the foil being covered by the glass container; this resulted in about 700C for the glass/foil shell. In this case, the foil is the medium for transferring radiant thermal energy to the outside, and aluminum foil has an emissivity of about 0.04, and so theoretically the foil could have gotten to 4370C. Therefore the foil’s measured response in this scenario is still well within the bounds of the standard application of energy and heat transfer of the traditional physics that Principia Scientific International is an advocate of.

If the Slayers have ever required experimental evidence to help support our position of the traditional laws of physics that the laws of thermodynamics are also obeyed by radiation and sources of radiation, the experimental work by Mr. Watts and Mr. Wilson has nicely provided that. Unfortunately, neither Mr. Watts nor Mr. Wilson performed a quantified scientific analysis of their experiments, and instead, a rather crass interpretation of their results was pursued with no scientific analysis of their numbers or experiment at all. It becomes very burdensome for those familiar with theory to have to deconstruct every misinterpreted experiment that is presented to defend an idea which has no basis in reality in the first place, as we have shown. Let us not forget that this experimental debacle has its source in the challenge brought to PSI by Mr. Watts and Dr. Spencer, which we answered and which they promptly ignored, and then changed reference frames with an experiment they didn’t scientifically analyze or quantify or discuss the theory of or understand the principles of. The whole sequence is queer, because the simple fact of the matter is that PSI has already published both model and empirical data which proved that the greenhouse effect models are wrong and that the greenhouse effect doesn’t exist. This is of course precisely what Mr. Watts would like to ignore, it seems, which is a curious state of affairs for someone who likens themselves to be an advocate of science, let alone someone who makes the appearance of being a skeptic to anthropogenic global warming. Insisting on a crass interpretation of a simple experiment is hardly skeptical, let alone scientific.

Principia Scientific International would like to offer its own challenge available to all people in regards to the assumptions which underlie climate science. We simply ask for people to vote for what they think constitutes a valid scientific model of the Earth and climate:

In science, the Earth should be modeled as

  1. flat, or spherical

  2. static, or rotating

Sunshine should be modeled as:

  1. cold with the Sun twice as far, or, its real value

  2. uniform and even with no day or night, or, uneven with a day & night distribution

Water should:

  1. not exist, or, be present

Clouds should be:

  1. assumed, or, created by sunshine

Equations and physical parameters should be:

  1. independent of time, or, time dependent

As PSI has repeatedly shown (as if it isn’t obvious), the first set of answers correspond to a fiction, and it is this fiction which creates the greenhouse effect. What has always been curious in this debate is how some people claiming to advocate for science do not want to consider what happens if researchers create a model based on the second set of answers, the set of which actually corresponds to physical reality. Is the reason as simple that the realistic model of the Earth is not desired because it does not have the greenhouse effect? Science can be advanced with better physics, better knowledge, and better models…why not do that?

The underlying error is that the models which require the greenhouse effect dilute the power of sunshine to one-quarter of its actual value, and so another fiction needs to be created to make up the difference. It is essentially the same thing as claiming that the voltage across a circuit can be increased by the light and heat the resistor produces. From time to time the claim is made that the input, even though it is modeled at only -180C, is actually capable of heating things up to the spectral temperature of sunlight (~5778K) if greenhouse gases trap the outgoing radiation. This is a falsehood. The only way to get the incoming solar spectrum to produce higher temperature than its local flux density is to either 1) have a surface with low emissivity, or 2) re-condense the sunlight with a mirror or magnifying glass, to undue the photon-density decrease experienced by the wave-front undergoing inverse-square law diminution while travelling from the Sun to the Earth. Greenhouse gases do neither of those things. Once the incoming spectrum is absorbed at the Earth, all spectral information regarding the source is lost, and turned into heat. It is this real-time heat that drives the climate in a spherical rotating Earth with day & night. This heat subsequently has its own, new and unique, spectral signature at a much lower temperature, and just like the light bulb, any subsequent interaction with it cannot augment the source of the action. The source is not a Sun twice as far away at one-quarter the power, the source is the real sun at full power.

Mr. Watts and Mr. Wilson desired to conclude that an input could be increased in temperature with its own output, in some way or another, because this is what is required for the fiction of the greenhouse effect. This is and has always been a violation of thermodynamics, and the traditional understanding of physics which PSI is nearly alone in defending. Their results proved the exact opposite thing of their claims and fully support the position of PSI. Mr. Watts and Mr. Wilson were not aware of what their results proved, because they did not attempt a quantified scientific analysis.

********

 

Additional comments by Joe Postma from his blog:

 

Incidentally, the light bulb experiment such as this is something which is performed by undergraduate physics majors…at least, it was by me when I was in university getting my B.Sc.  Mr. Watts does not have such training, and so the result of the lack of such training has been made apparent here.  The equations to describe what was happening are about the simplest you can find, and are learned in first-year undergraduate physics.  Mr. Watts and Mr. Wilson have proven with their experiments that no additional heating occurred than what was the original energy input.  No one trained in physics should have expected otherwise.  Thus, their experiments do not lend support to a radiative greenhouse effect as is promulgated by the models.  What is worrisome is that no one else, other than PSI and a few people commenting on blogs, is calling Mr. Watts out on this abuse of physics and empiricism.

 

It is insane that people pretending to don the mantle of science work so hard and so crassly at trying to prevent better science from being done.  Amateurs with science blogs are hurting science and are harming people’s minds and are creating cults of personality around their obviously simple-minded egos; could we ever expect Mr. Watts to understand the science in his experiment?  I think not.  All that they have to create the GHE is this fictional simplification of the Earth into a flat plane with a Sun twice as far away that has nothing to do with the real physics of the real Earth.

 

It is a defined fiction, and they loveit.

 

These GHE beliefs seems really important to some people, for some unknown reason.  As you know, I can’t tell if it is a religious thing, if it just stupidity, or if it is malice?  Possibly it is all of that?  Some people really love the greenhouse effect, really love the fictional premises it is based upon, and they have some incredible emotional attachment to it.

 

So, what to do?  Because the fact of the matter is that you cannot use Logos to educate or convince any Mythos person about anything; they have their beliefs and they have an emotional commitment to them, and no Mythos person can ever think beyond this emotional directorship because that is specifically what defines them.  Logos vs. Mythos people process information in completely different ways, and in fact they may not even recognize the same types of information at all.  Mythos people literally do not even see the same information that a Logos person sees.  A Logos person has simply never been able to convert a Mythos person to Logos by presenting them logos information; this is something that a Mythos person has to do by themselves by some miraculous transformation of their own psyche, some experience or some event that forces them to begin to recognize Logos information, because they willed it of their own spontaneous desire.  It happens randomly and unpredictably.

 

But the point is, because I had asked “what to do”, is that perhaps you must let people have their religion.

 

If the new Mythos is to make a religion about the atmosphere, about cold things heating up hot things, that the greenhouse effect is good and creates life but it can also punish you if you disobey it and then it will destroy life, that you need to be subservient to and worship the atmosphere and Earth, etc., well, maybe that’s just fine for now.  Maybe this set-up needs to be dialectically explored for a few generations, or even millennia, for some reason or other.

 

Maybe we need to kill and murder each other over it for a little while.

 

Perhaps we can have a system where we are taxed for the air, and where our slave labour payments are made in “credits” of air, and then we can have an underground society of Logos adepts who are secret heretics of the ruling order who are trying to free the human mind and soul from its atmospheric bondage.

 

I mean, it’s not like this would be new or original or anything, it would just be exploring all the same old archetypes in a different skin.  There would be some new stuff which comes out of it, sure, given that the conditions and the language is slightly changed, but, it’s not like this isn’t specifically and exactly the history of the human condition.

 

It (the GHE) is created so that people can waste time debating endlessly about a meaningless simulacrum, while at the same time other people try to tax them for the air.  Printing valueless money and charging interest on it is one nauseating thing, unfortunately, we know all too well in this world; taxing the chemical basis of life itself, carbon, is just getting greedy.

 

May Cold bless all of you and keep you Warm.

 

It may not be known to all yet, but this marks the end of the debacle of climate alarm and the greenhouse effect, because this is what the defence of the GHE and climate alarm has been reduced to, and it proves itself to be void.  In truth you can feel some empathy towards these GHE followers because they really, really want to be believe that the Earth is flat and static and that sunshine is cold and the Sun is twice as far away, that the coldatmosphere heats up the hotter Earth and that cold things heat up hot things by various verbose means, etc.  These beliefs seems really important to them for some unknown reason.

 

They get really upset if you say you want to model the Earth as spherical and the Sunshine as its real value, and do it in real time, and also have water, etc.

 

It seems like such an idea really makes them sad.  And then it also makes them really mad.

 

It kind of makes you feel bad when you take it away from them…I mean, when you see what it does to them.

 

On the other hand, this also marks the end of science, and even physics.  The equations to show what their experiment was doing are basic.  I mean, if you asked random people on the street the questions of the poll presented in the above article, everyone will answer the correct way.  Implicitly people will know what the correct answers are.  However, most people will not know what their answers imply, and most will still accept the prognostications of the appearance of authority, because they won’t have the knowledge or training to put it all together and identify the contradiction.  People could understand it quite easily, this is definitely true, because I’ve tried it on random people and they do get it, easily.  What most people don’t accept however is that such big lies can exist – that is the difficult thing to convince people of, that such huge mistakes can be made by people who, well let’s face it, pretend to be smart.  It is probably too disconcerting to imagine.  But, if you work around “smart” people like I do, then you know just how possible it is.

 

It is really easy to rule people…their behaviour and their minds, etc.

 

You simply lie to them.

 

Read more from Joe Postma at climateofsophistry.com

 

 

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