Energy and Intensity: Analogy Needed
    By Tommaso Dorigo | December 13th 2010 12:34 PM | 66 comments | Print | E-mail | Track Comments
    About Tommaso

    I am an experimental particle physicist working with the CMS experiment at CERN. In my spare time I play chess, abuse the piano, and aim my dobson...

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    In the past weeks I have been writing a piece about the Large Hadron Collider for a science popularization magazine, and I found myself squeezing my brain for a good analogy to the work of particle hunters. The idea I had was to convey the importance of energy and intensity, two parameters which must both be maximized by a particle accelerator in order to reach deeper in the structure of matter.

    Anybody who knows a thing about particle physics is familiar with the fact that the higher is the energy of a particle collider, the more massive particles it can produce. If there is a particle X whose mass is Y, there is no chance to produce it at an accelerator whose maximum energy is 0.1 times Y: you need to reach or exceed collision energy Y if you want to see X. So this looks like a concept which is not too hard to get a grip of.

    Much harder is to explain why more intense beams are required to probe deeper. In December 2009, when news of the first particle collisions at the LHC made headlines, it was not infrequent to find people asking what had been the result of the experiment. It was not easy to explain that the experiment will last two decades! Intensity is needed, and time. The product of illumination and observation time is what eventually provides a better chance to make out the subtler features of low frequency phenomena.

    In the end, I have put together the following analogy. I am changing the wording a bit (and thus worsening my perfect prose) because the magazine comes first, and am also summarizing it since I am taking it out of context, but the meaning is there:

    "Like speleologists who in their explorations of the underground find themselves leaning on the edge of a huge unknown chasm, physicists explore all the territory they have a chance to light up with their lamps. To see further, they need more powerful lamps, capable of illuminating deeper, puncturing the darkness of the cavern. But their light also needs to be as intense as possible, and to shine for longer time, to allow them to make up more clearly what they are illuminating."

    Of course, the analogy is imperfect because for light, intensity and energy are rather interchageable concepts. Maybe by thinking along the lines I have provided above, some of you may suggest a smarter analogy ?


    Perhaps a slight improvement:

    Energy -> brightness of light. The brighter the light, the *deeper* into the darkness it illuminates.
    Intensity -> number of lights. The more lights, the *broader* the search, and the more likely you are to find the interesting things lurking at any given depth.

    Vladimir Kalitvianski
    Intensity determines the exposition time. The same static photo can be shot with different light intensities and different expositions, providing their product is a suitable invariant.

    The energy is more like a light color. Admitting the atmosphere is foggy, it is preferable to use a short-length waves to see "deeper" or "farther". This analogy is rather misleading, though.

    You can say that the higher energy of the frontal inelastic collision is, the more deformed target will be, and each final state of the deformed target is a different "particle" or a feature of nature. This is in fact reality, not analogy. And higher intensity is necessary for increasing the number of rare frontal collisions.

    The particle physicist is trying to photograph tiny particles. He needs not only an intense light because they are tiny and easy to miss, but it must also be of the right colour (frequency/energy) to see the particles he is after.

    My best shot for a non-technical audience.

    Vladimir Kalitvianski
    No ,the problem is not to see the existing tiny particles but to create new ones. Particles are not "tiny", to be exact.
    Of course. But that doesn't translate well into people's everyday experience.

    Vladimir Kalitvianski
    I think people nowadays are sufficiently literate to understand that the more energy you use, the "newer" item you produce.
    "for light, intensity and energy are rather interchageable concepts"

    For light, intensity and energy are not interchangeable. Remember the photoelectric effect.

    Vladimir Kalitvianski
    Yes, one should distinguish the energy of a singe projectile and the energy of a beam. The latter can be increased with increasing the number of projectiles of the same "individual" energy.
    Mark, thank you... But I am speaking of lamps here, and illumination. If I were to insert quantum concepts I would be making five steps back to make one forward...

    Is there any point in talking about intensity? You need a given number of events to falsify a given hypothesis. More intensity just means you can do it faster.

    How about searching for fish in a lake by bringing up buckets of water? Energy = size of bucket. You need the buckets to be at least as large as the fish you want to measure (but obviously buckets just the size of the fish won't get many; it's better to have larger ones). To be certain you have the real monster fish instead of just large specimens of the plain old cod, you need to measure many. Intensity is just how many buckets you can get per day.

    Rhys, is right. Energy refers to the effect of a single particle/photons. Intensity refers to how many particles/photons you can deliver per second. Together they determine how often you might see an event requiring a certain amount of energy.

    In first year chemistry, to explain the photo electric effect, we sometimes use the analogy of soccer players kicking a soccer ball out of a pit. If the players of the children's league are too weak to kick a ball out from a certain depth pit, it does not matter how many you send down into the pit. If instead, you send down a stronger adult soccer play, you can kick the ball out with just one player. If you have many balls in the pit, you can get more balls out per second by sending in more adult players. Each ball that comes flying out, won't have more energy. You will just get more per second.

    So the analogy is, the strength of the player corresponds to energy and the number of players participating  corresponds to intensity.

    Hope that helps. 
    Citizen Philosopher / Science Tutor
    That's moving in the right direction.

    During a hail storm, if the hail stones are very fast but few each stone can damage the apples, but the are so few that they don't cover the flowers. On the other hand, if there are a lot of hail stones, even if they are not very fast , the apples are safe from damage, but the amount of hail could smother the roses.

    I think Steve Donaldson’s explanation gives a lead.

    (1) You need the adult to kick the ball out of the pit.  Not only that, but

    (2) you have to land the ball in a basket which the adult cannot see from the bottom of the pit.  (Mixing games somewhat!)  So maybe you need a million kicks to get one in the basket!

    Robert H. Olley / Quondam Physics Department / University of Reading / England
    Vladimir Kalitvianski
    Indeed. Let us fire in the air. The faster bullet, the higher altitude reached, another bird specie may be shot.
    Your original analogy should be changed, it uses almost the same idea over again. Instead try this: If you were in space but had to use machine guns instead of laser beams: It's like how powerful your bullets are from the MG ("energy"), but also and how many per second ("intensity".) Powerful individual bullets allow you to break larger asteroids but you won't hit very many if the fire rate is low.

    Yeah, intensity is about luck. If your intensity is low, then in order to see something cool, requires too much luck.

    It's like buying lottery tickets. If you want to be sure that you win big, you have to buy a lot of tickets. And that gets expensive.

    Thanks everybody for your valuable input. I have no time now to answer each in detail, but will take a closer look tomorrow.

    Frankly I think that this analogy, although cute, is more misleading than explanatory, as is any variant proposed in this thread that makes use of the familiar concept of luminosity.
    I think that in this specific case no analogy is needed, as it is easier for the general reader to understand the concept the same way a specialist figures it, rather than through an analogy.

    I second that. Seriously, you should consider just explaining it as it is instead of confusing with analogies. It is not so difficult now, is it (E~m and more events for better stats). The analogies may fit somewhat in your eyes (since you know anyways), but for those not in the know and additionally not used to great care with the written word, analogies mostly transport exactly what was not meant. One thing that makes my eyes roll about POP science, it is these always misleading analogies that very very seldom tell the lay reader more than that physicists are awesome and they are too stupid for the real insight anyways plus a mistake on top as the icing. It leads to all these misunderstandings and conservation of mystic, like the esoteric veil around black holes or the close to religious appreciation for energy. Basically, it is the backfiring of outreach, achieving the very opposite of what it should do. (I feel kind of serious about this issue, basically the reason of why I blog in the first place, so I included these links to my articles - not trying to use your comment thread as a billboard, promised.)
    Hi Sascha,

    while I understand your arguments,  I do not second them. First of all, a popularization article must take into account several factors, not just accuracy, correctness, and help to the cause. Prose is important, and the need to not kick away the less knowledgeable readers at line three is another crucial consideration.

    Besides, of all readers those that might get misled are the ones who have the means to get the analogy for what is worth; to all others, the analogy actually may do some good. I have used metaphors in my blog for years, and I have some experience with the effect they have to the readers. I agree with you that one must avoid the kind of analogy which is only meant to instill awe, the boasting kind, so to speak. But analogy is a powerful learning tool, and I am unmoved by your fears.

    And anyway, I have Dick Feynman on my side. He loved analogies and used them as much as he could, too.

    To show you that I am quite serious with the issue, too, take this one:

    You mean the one where you argue that a bar of chocolate releases "a speck of chocolate" (already the first commenter objected)? If massless is weak but goes far, do gluons fit into that? Ok, I do not want to discuss that particularly questionable analogy right there. I am not putting down good pictures - in fact I do myself often rely on intuition pumps, like dividing bacteria to explain the slowness of cosmic inflation. However, such comes in if it helps more than it confuses, accompanied by disclaimers and so on. In your case here (large energy and intensity), I agree with Andrea, namely it is unnecessary and only adds confusion. Who ever claimed that just sticking to the facts necessarily must "kick away the less knowledgeable readers at line three"?
    I am not aware of any great scientist or teacher of science that did not make extensive use of analogies to explain science to the general public or to students studying to become scientists. Someone already mentioned Richard Feynman, but of course the most famous example must be Einstein himself, riding on beams of light and so forth.

    I use analogies all the time in tutoring physics and chemistry to college students. In my experience it really helps them develop a deep understanding of the topic at hand.

    Sascha, your point that analogies can do more harm than good, is well taken. That just proves the point of how powerful analogies are. Bad analogies do harm. Good analogies clarify. Hence the importance of crafting good analogies.
    Citizen Philosopher / Science Tutor
    I value your opinion Andrea, but you should consider that there are other factors to take into account... See my reply to Sascha below.


    Here is what I offer for a simple-minded analogy:

    Imagine taking a shot on the arm from a cylindrical syringe filled with antibiotic fluid and with a standard needle at the end of it. The thinner the needle, the higher the pressure felt and the deeper the penetration of fluid in the skin. This is because pressure is force per unit area. The larger the force applied to the piston of the syringe and the smaller the area of the needle, the higher the pressure and penetration depth. This is the analog of INTENSITY.

    The product between fluid pressure in the cavity of the syringe and the volume of fluid enclosed in that cavity is the analog of ENERGY. The larger the force applied to the piston of the syringe and the larger its cavity, the larger the energy contained in the shot.

    Hope this helps.



    Hi all,

    thank you for your criticism and the possible improvements you suggested. I think one point which has escaped most of you is that a piece for a magazine must not just try to be "correct" and explain things in a understandable way; it must also be readable, and avoid presenting a condensate of facts which makes most readers flip the page. I think what is missing from the analogy I offered is a better explanation of why one needs to observe for longer time something to make it up more clearly; in truth, the original text in fact does it somehow, while the summarized one I offered above does not.

    I will try to improve the text... I see that many here do not like analogies, but you are a quite selected set of readers, quite unlike those that will be presented with my text eventually, so I am not too worried... Also, luckily enough I will have experienced editors who will consider the matter thoroughly before publication.

    Just to be clear, I'm not against analogies tout court, but against this specific one :)
    But I see that you are aware of what is probably the biggest problem of the analogy as you have presented it here:

    "I think what is missing from the analogy I offered is a better explanation of why one needs to observe for longer time something to make it up more clearly"

    But if the longer version of this text makes this point clear, then my objection does not apply.

    I think one commenter above got it right - bullets.
    People have also seen this many times in films, especially in slow motion.

    Imagine your target is a bullet inside which is an unknown crystal. The aim is to discover which crystal. A hammer doesn't have enough energy; you need to fire another bullet into it to smash it up. The faster the incident bullet the more chance of smashing it - higher energy. But that's slow and kinda hit-and-miss, literally. Use a machine-gun and you're more likely to crack it - higher intensity.

    This also works if you have 2 machine-guns firing into the space between them.

    That's my tuppence worth!!
    For me themachine-gun analogy sonds too martial - could evoke misleading associations putting HEP into the wrong context.

    Best one so far, in my opinion.

    The speed of the bullet corresponds to energy, literally, as in kinetic energy. The number of bullets per second per square meter corresponds to intensity - again, spot on. Now, instead of a crystal, say a walnut. The idea is that you are trying to crack a walnut with a bullet, from a great distance, while it is falling from the tree - not an easy task! You need high intensity, just to have a chance to hit the damn thing, and on top of that your bullet must have enough energy to crack the nut if it should happen to hit.

    Still not perfect perhaps, but getting there, I think. As Rycharde points out, really the bullets are also the targets, so we should be firing walnuts against walnuts. However, the point of an analogy is not to explain everything, but rather to explain a particular concept. Here the task given to us was to design an analogy to explain the difference between energy and intensity and why we need both high energy and high intensity in these collision experiments.
    Citizen Philosopher / Science Tutor
    Well how about with astronomy, such as Hubble's Ultra Deep Field where if its powerful telescope is pointed at a small part of the heavens seemingly void of stars if long and multiple exposures are taken the region is revealed to contain thousands of galaxies with some being at the edge of the observable (light cone) universe. The double slit experiment using single photons where over multiple firing revealing quantum interference could be seen as the same.

    I am a naval arhitect and marine engineer and this is my understanding of the LHC beams intensity:
    When particle "bullets" meet in the collider, coming from opposite directions with high speed, there is a good change they touch each other at the edges and not head to head when they collide. These collisions will not produce any "good" debris. Furthermore, even head to head collisions produce many many kinds of debris and we are interested only in the rarest of them. We need billions and billions of "bullets" to collide in order to have a chance to win the lottery and observe the rare debris. More "bullets" in other words is higher intensity.

    I find analogies are useul when I teach, but I try to keep them as relevant as possible to the course I'm teaching and to the common background of my students. Teaching physicists of proven ability, I'd run with something along the lines of a simple wave: amplitude is analogous to energy, frequency is equivalent to intensity.

    Whatever you decide, enjoy the teaching - it's a lot of fun when you settle into it!

    Ouch! I think this is what Sascha was worried about. Sorry, Raphe, but it in the case of waves, frequency is energy not amplitude. The slowly rising tide may have great amplitude, but it is the smaller, "choppy" wave that cause more erosion of the shore. Intensity, on the other hand, relates to how the energy is sustained over time at a particular location and is defined as Joules (energy) per second per square meter.
    Citizen Philosopher / Science Tutor
    If you want to take a sharp picture of your bedroom at night, you need a light bulb and a camera.
    The light bulb has to be connected to a high enough voltage: the higher the voltage, the higher temperature the light bulb reaches and the higher frequency the photons will have. To emit enough light in the visible spectrum, the light bulb has to be connected to the right voltage - for example 230 Volts as required in the European Union will heat the wolfram to thousands of degrees and a lot of visible light will be emitted by the hot light bulb. Photons of visible light have a higher energy than the radio wave photons - and correspondingly, their wavelength is short enough (half a micron) and such light is enough to see structure as fine as a micron.

    The voltage is analogous to the energy one must squeeze into one proton at the colliders. In fact, it is not just an analogy: the protons at the LHC are currently accelerated to 3500 GeV of energy which is exactly the energy that the proton gains if it moves between two wires with 3500 billion Volts in between them. Note that we need a much higher voltage to study the particle physics than what your light bulb is satisfied with. It's because we need to resolve much shorter distances than one micron.

    However, your bedroom camera also needs a sufficient exposure time: you need to set a reasonable shutter speed. If the exposure time is too short, the picture will be way too dark. Even if you use a Photoshop to increase the brightness, there will be too many dots and the contrast will be lousy, with lots of noise dominating over the smooth signal. The exposure time has to be a significant fraction of a second.

    However, a camera is able to absorb a large portion of the photons that enter it. The colliders have to collide protons against each other. It is much harder to hit one proton by another than to hit a macroscopically large digital camera by a photon. That's why the exposure time needed by the particle colliders may sometimes be counted in many years. Certain patterns - such as the existence of the bed in the bedroom (or a pion in the particle collider) only need a relatively short exposure time. However, if you want to be able to read the newspapers on your bedroom photo, you need to collect many more photons. Analogously, you need years of the proton collisions to acquire a sufficient "signal" for your picture proving a Higgs boson to get sharp enough so that other physicists may believe that the picture contains a Higgs boson, indeed.

    The total number of photons that your digital camera needs for a sharp picture may be obtained by increasing the exposure time; or by increasing the number of light bulbs you use to illuminate the scene. The same is true in particle physics: one may wait for a longer time; alternative, one may increase the "number of light bulbs" or the number of protons in the beams (or how accurately they're directed to their opposing friends): this "intensive" quantity is known as the luminosity. If you increase your instantaneous luminosity, a shorter exposure time will be enough to obtain an equally sharp picture of particle physics.
    Luboš, your bedroom analogy rather refers to a fixed target setup. I wander how you would tranform this picture into a collider analogy ;-)

    Dear Anonymous,
    my bedroom is moving by 30 kilometers per second - at least relatively to the Sun. I admit that people who still believe the geocentric theory - namely that the Earth is a fixed target - deserve another, more dumbed-down analogy. ;-)

    Best wishes
    Bonny Bonobo alias Brat
    Lubos, I love your bedroom analogy. I wish that scientists would explain concepts more often with the use of analogies, they utilise existing frameworks to help build knowledge, for me anyway.
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at
    Thanks, Helen - and before you wrote this, i accepted the science20 palship offer over here which is likely to be more symbolic than a practically used gadget. ;-)
    Bonny Bonobo alias Brat
    Yes Lubos, I realise that.
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at
    Vladimir Kalitvianski
    Your learned lecture is okayable except for one point: why one needs more energy to resolve shorter distances? And how do you "resolve short distances" if you create rather than observe? It is an essentially "destructive" (or "constructive") way of observing, don't you see it?
    Vladimir, the relationship between wavelength and energy is not alien to you I think, so I do not understand the first part of your question.
    As for the second part, I do not really understand what makes you uneasy. To see what's inside a billiard ball you break it, is it so surprising ? Concentrate on scattering if you do not acknowledge of having studied Mandelstam variables and the equivalence of crossed  processes.

    Vladimir Kalitvianski
    My questions are addressed to Lubosh, not to you, Tommaso. And we mean a layman as your reader, not me. They are not my questions. A layman needs a microscope to resolve short distances.
    Dear VK, I am grateful to Tommaso for answering your questions - it's his blog and his knowledge of theory is undoubtedly enough to answer your questions in the same way I would.
    High-energy particles carry high frequency because the energy is linked to frequency by E=hf, the (time) periodicity is 1/f = h/E, and because the objects move almost by the speed of light, the corresponding wave also have the wavelength lambda = c.t = c.h/E. So the higher energy, the shorter the wavelength of the associated wave in quantum mechanics.

    One actually always needs to break microscopic things in order to see. Photons that arrive to the digital camera's sensitive pixels or the retina in our eye break the atoms - they ionize them and kick their components (electrons) out which is translated to voltage and information. The colliders are qualitatively doing the same thing except that they are breaking much smaller and much more tightly bound protons - before they break the electronic shells of atoms in the detectors (in various ways, depending on the part of the detector).

    If you don't break any things, not even atoms, you can't see.
    Vladimir Kalitvianski
    Dear Lubosh,

    I have no objections ;-) except you are teaching me here the things I know. In particular, if you read my article [1], you will find a statement that classical mechanical notions correspond to the inclusive (destructive) picture. As well, you can find wonderful pictures of elastic (non destructive) processes in my post here, so some times one can "observe" without breaking the target ;-)

    [1] (published in Cent. Eur. Journal of Physics, 2009).
    I am "teaching" you these things because you have asked me to do so. Have you forgotten? It is a really thankless job to be discussing with you. You annoy someone and urge him to discuss with you and answer your elementary questions, but if he does so, you criticize him for telling you things that you allegedly knew. So why did you ask?
    I won't comment on your paper. At any rate, seeing is only possible by "objects" which are bound states composed of components that are bound states themselves, and all the discrete signals that can propagate must actually break some of these bound states, so seeing is always destructive - although sometimes the destruction is more penetrating than otherwise.

    Vladimir Kalitvianski
    You were proposing an analogy to Tommaso with saying to a layman things about higher energies instead of saying of more powerful microscope. So I asked you for the layman whom you failed to give a reasonable analogy. Again, I personally do not have questions to you, Lubosh!
    Vladimir Kalitvianski
    Lobosh wrote:
    "At any rate, seeing is only possible by "objects" which are bound states composed of components that are bound states themselves, and all the discrete signals that can propagate must actually break some of these bound states, so seeing is always destructive - although sometimes the destruction is more penetrating than otherwise."

    I agree although I am afraid you think the electron is not a "bound state" but "elementary" particle.
    I haven’t gone in for the things myself, but perhaps a lottery analogy might help.

    The required amount of energy is the currency needed to buy a ticket, but the intensity needs to be high enough to “buy” enough tickets to achieve a reasonable probability of winning the lottery.
    Robert H. Olley / Quondam Physics Department / University of Reading / England
    your bid easily wins the contest. I like it a lot: simple and clear. Thank you!
    Now, whether I use it or not also depends on my editors... But I do think it is worth remembering!


    I think you are misleading us, your cohorts...

    You asked for an analogy to help explain energy and intensity.....and why the maximising [of both] is necessary for the reaching deeper into the structure

    Yet you pick the answer which does not do either....though it may be simple and clear, it makes me feel that the purpose of the LHC is to lose energy and money, as Luboš suggests

    I think I'll fire a hose at you  ;-)

    The only problem is that if you buy many tickets, what you guarantee is not a profit but loss. By selling all (or significant fraction of) the tickets, it's the lottery company that makes profit. That's why they organize the lottery. So the buyers as a whole - and, logically also any big buyers - inevitably make the same loss.
    Moreover, the energy in the analogy is completely absent. One ticket and one unit of a currency are just two different units of energy. But if one converts one to the other, i.e. one megadollar to lottery tickets, the only thing he can get is many tickets - which was called luminosity. So this analogy doesn't have the two degrees of freedom - energy and luminosity. It only has one of them. It is a pretty fundamental problem given the fact that the task was to create an analogy that explains why there are two.
    You can explore the innards of automobiles by pointing two lanes of traffic at one another. Energy is the cars' speed and intensity is the density of traffic. Increase both to get a lot of high-speed crashes. I think this is a more direct analogy, and it's got the titillation of violence to make it memorable.

    You may also pick a dentist, adjust the dental drill to a high enough speed, so that it actually starts to break the teeth, and force the patient to spend a sufficient number of minutes until the doctors gets inside the tooth.
    Too bad that a good Czech joke can't be fully translated.

    The patient asks: how much time does he have to suffer?

    The doctor answers that it may take some time because he needs to get to the very nerves.

    The patient complaints that they will have to work until the morning because his nerves are already in the asshole (destroyed). ;-)

    Having read many of the comments, it seems to me the destructive bombardment of the LHC beams, can maybe best be analogised by a Fireman's hose
    Firing water in a spray, at, say a rock, has enough energy to make it wet, but increasing the pressure/intensity, i.e. GeV/TeV equivalent, makes the water blast away the example rock

    If you have been out in a storm, you will know how strong rain driven by high winds sting your skin also, but how many have felt the effect, of walking past a street sign, or a shelter, and felt the pressure on only one side of your body, due to the masking effects of the other object causing you to spin on your feet?

    I could imagine being blasted by a hose powerful enough to tear my clothing to shreds, if the hose jet were highly focused, increasing the intensity of pressure to area, {as with a metal cutting waterjet} but if from 2 opposite, or nearly opposite points...?...I'd be giddy, or naked and sore LOL
    I envision that effect to be similar to the alignment of the collider beams, and the spinning to unpredictable results of alignment of the beams

    To show the light effects of collisions I can only think to use a separate analogy, of a Thermionic valve, which may not be so well known as a Fireman's hose, and therefore, not so appropriate
    Essentially the thermionic valve has a heater to warm a cathode, which releases free electrons into the space above it...but only when a positive connection, relative to the cathode is made do those electrons flow to the positive anode point, and complete the flow path, causing the light in the valve to vary with electron flow,, appearing at first a warm pink, as heated electrons just migrate upwards carrying warmth, up to a cold blue at the ultraviolet end of the spectrum, depending on the applied pressure, or voltage and/or frequency or number and intensity of electrons making the journey, with the collider, I imagine

    I find the analogy with the speleologist misleading: a powerfull light means usually a more intense light, so the two concepts get blurred.
    I like much more to talk about telescopes: you need a large objective to read a newspaper from far away, say the top of a skyscraper (just trying hard for a long time doesn't help if the objective is small), but you need time to read it once you manage to distinguish the letters.
    If your lens is almost large enough you will have to guess some of the letters, which will take you a long time, the sharper the image, the faster you go.
    Hope it helps... assuming you get to read this far down the comment thread.

    In my analogy the objective's size goes for the energy.
    The analogy for the higher intensity is not yet perfect: I could have more than one person reading at once to go gaster through the newspaper, say, looking for fancy words.

    Vladimir Kalitvianski
    I propose a Babylon Tower analogy.
    Good one, Vladimir! That does appear to be where we have come to, despite best of intentions.

    Note: If it takes more work to explain a particular analogy than it does to explain the original concept, then maybe that particular analogy is not going to be that helpful. :-)
    Citizen Philosopher / Science Tutor
    Dear all,

    I fear this thread has had even more success than I hoped for. I am happy to see both different opinions on the value of analogies in the popularization of science, and different proposals on how to change/improve the starting bid.

    I think Robert Olley's analogy of the lottery ticket is by far the cleanest and clearest. It is also nice to relate directly to money spent (to build the machine!), although that too may be misleading. In the end, if this thread convinces me of something, it is that anything can be misleading, if used without the necessary caution.

    Thanks all for your contributions... I suggest you try your favourite analogy of the LHC energy and intensity frontier with your grandma (or granddaughter if you yourself are over 60), and then report here your findings on the effectiveness of the example.

    To shoot a basketball blindfolded through the hoop at the opposite end of the court, you first have to throw the ball hard enough for it to reach the other end. Then you have to repeat the attempt often enough and long enough to finally get the one lucky shot that happens to fall perfectly through the basket.

    This one sounds pretty good!
    I think that an good analogy in this case, along with the actual interpretation would serve well.
    I like the idea of using speleologists.
    I have a rock, and a hammer and I need to see inside the rock,
    the heavy powerful hammer would signify the energy,
    the pointed shape of the hammer signifies intensity,
    your skill in hitting the same spot over and over would be luminosity
    and the better you handle the hammer, the better results will be forthcoming.

    See...a little geology never hurt anyone...;?)

    Oh sorry, I forgot to add that your "skill" in handling the hammer could be analogous to the "tuning of the beam".
    Hope this helps.

    Daniel de França MTd2
    Let`s think in terms of a digital camera and a tree in the forest.
    Energy is related to wavelength. So, we have that energy "means" resolution.Intensity is related to luminosity. So, we have that intensity "means" brightness of the flash light.
    Studying particles is taking photos of trees and determining to what species it belongs and its characteristics.

    Usually, the heavier particles are the longer are its decay chains. Decay chains are like the branches of trees. Since branches are very small and complicated, and usually gets mixed with the other trees branches, a higher resolution camera(energy) is needed to tell apart the individual. So, we increase the resolution of the digital camera, that is, its energy. 

    But resolution is not everything, given that it does not guarantee we may distinguish the boundaries of the branches of a tree from others belonging to different trees in the background. So, we have to use a stronger flash light.

    As per my above comment;
    One aspect that I would say about the analogy I provided,
    I might leave out any mention that the splaying of fragments/subatomic particles resembles actuality, thus leaving your audience to follow that logical conclusion on their own and in doing so concreting the analogy in the mind of the reader. It always helps to leave out a couple steps in an analogy so the thinking person can continue and follow your line of reasoning, though it is imperative to state that the analogy can not be carried out indefinitely, as there is no such thing as a perfect analogy.

    The written word be it common or a higher language and even mathematics is just a structured analytical analogy. Experience rules…such is the world.