When do the world records stop

EDIT: yeah, in the 50 if you run the numbers 22 seconds for 50 meters is 2.27 m/s, so in .01 seconds the swimmers travel .02 meters, or 2 cm. That's close to an inch for the metrically challenged originally posted by knelson Also, if you run the numbers using a very conservative speed of 1.73 m/s (which is slightly faster than world record pace for the 1500 meter freestyle...since 29 seconds per 50 meters is a little under world record pace and that converts to just under 1.725 m/s) ........you find out that a difference of just 1 cm in the length of a 50 meter pool will then account for just over a 0.17 second time difference. This all then supports my claim that going from a scale that differentiates times that difffer by 0.01 seconds to a scale that difffereniates times that differ by 0.001 seconds has no real significance when it comes to things like the small differences in pool lenghths (especially for races of any significant distance)........The real point is that "some" kind of scale must be used...and since even a scale based on 0.1 second increments is inadequate in certain situations, we must base the scale on sceneraios like differentiating between two swimmer's times in the 50 meter freestyle who are swimming in the same heat together.....It then is completely inconsequential at that point when it comes to extending the scale to all other situations (such as comparing times from different pools...etc...) newmastersswimmer

I just had to go back and double check your profile. Imagine my surprise when I saw "Math Professor" as occupation. I'm proud to call you Chief of R&D for "Slick". BTW, I have this "issue" with my check book. They say it has something to do with balancing.. I can hardly figure my yardage in the morning. I'll take on marketing...they say lawyers are "slick". Seems like a nice fit, huh? What does this so called "balancing a checkbook" thing mean now??.....My wife does all of that stuff for me.....she insisted on it....(along with other things like laundry for example...I don't even have permission to get within a certian number of feet from the laundry room!!) Yaeh, I guess I could do the R&D for "Slick" Enterprises.......And I hope you are a good "slick" kinda lawyer...b/c I got a funny feeling we're going to need one if you know what I mean (and I know that you do!!) newmastersswimmer

it's how they can tell "almost" exactly when a ball hits the ground on a serve to see if it is actually in or out. There is absolutely NO doubt that there exists video technology that can determine who touched the wall first between two swimmers in the same heat whose times are no less than 0.001 seconds apart. originalyy posted by yours truely Wrong! (My opinion ) I've watched those tennis matches as well. For most balls, I agree, they do a better job than a human observer could. But I noticed that you said "almost", because there are cases where you can't tell. (The commentators run the footage backwards and forwards several times, and disagree with each other what the right call was.) That is why in tennis, you rule the ball "in", unless you clearly see it out. (I remember reading a tennis magazine article, where they placed a ball about an inch from the line, and took pictures from around the court. The line-persons vantage point could see the ball out. All other viewpoints, including the chair umpire, player, and TV camera view, the ball looked good. And this was without ball compression.) There is significant doubt for a 2mm difference in swimming... For cameras mounted overhead, water distortion will make it difficult see a difference that small. Also, do you count the fingernail, or the (soft) pad of your middle finger? It is also a touch pad, so a small amount of compression is needed to detect contact. One swimmer might have zero separation between their finger and the surface of the touch pad, but another swimmer (who touched 0.001 seconds later) who is moving faster could cause their pad to trigger first. Just because the clock electronics can report times to a thousandth of a second (or smaller), does not indicate how reliable (repeatable) those measurements will be. posted by Mattson in reply to my last posting Well I do respect your opinions Mattson (even though I disagree....as you do with mine)....so I will attempt to address all of your concerns the best I can: First: As far as how existing timing systems work that "claim" to discern time differences as small as 0.001:......I don't know exactly how they work (and so in all honesty I can't say how efficient they really are)...i.e. they could be flawed for a number of reasons like some of the ones you mentioned above......I would hope that the touch pads for such a system are: A) each of equal thickness to within as negligible amount possible so that even with small enough differences in thickness they will still be able to discern time differences on whatever scale they are designed for. B) They have a "sensitive enough" activation system so that whenever "any" part of the body comes in remote contact with them (finger nails or finger pads) they register contact to within at least 0.0001 of a second of actual contact. But like I said before, I don't know if these so called "super precision" timing systems have these features or not? If they are sensitive enough to touch as described in part B) ...Does that mean the wave of water your body carries along with it can set them off before actual body contact??? Secondly: I mentioned the "underwater" video timing system b/c I think I can understand that a little better (but maybe I'm fooling myself for thinking this?).....So first of all I don't know which engineers would design a video timing system for swimming that discerns times on a scale of 0.001 seconds that would put thier cameras above the water looking down from above???.....that seems a little rediculuous to me b/c of the obvious distortion problems.....I envision something more like this: Each lane has an underwater super high speed (and super high resolution) video camera just beneath the touch pads looking up towards the surface of the water (at a "slight" inward angle so as to see the area where the swimmer touches the pad at the finish of the race with the best possible view ...whatever angle that is...which may be debatable I admit)......The cameras for all 8 lanes would be synchronized to one another to within at least 0.00001 seconds (which should be reasonable enough to accomplish)......then lets say the super high resolution cameras had a speed of around 30,000 frames per second (I supplied a link below to a website claiming to sell high speed cameras that take 33,000 frames per second....I think the ones used in pro tennis matches run at more like 100,000 frames per second but I can't swear on it.....there tennis balls are routinely traveling at over 130 mph off the serve and require much higher speed cameras than for objects traveling at the rates that swimmers travel at).....so these cameras currently on the market can take approximately 30 still shot pics per 0.001 seconds.....The cameras being underwater and in relatively clear water means that the effects of light defraction will be negligible b/c of the relatively short distance of about 18 inches from each camera to the surface of the water (according to "Snell's Law" ....you can do the math if you like) when discerning distances that are within around half a mm or so.......now the only problem when examining a particular still shot to see when one swimmer has made contact with the touch pad and another swimmer is still a very small distance from the touch pad would be things like detecting fingernails (which are relatively clear and hard to pick up even with a high degree of resolution) and the possibility that tiney air bubbles could block a clear view of the area where a swimmer is either in contact with the touch pad or a small distance away from the touch pad...(maybe several cameras from below can be positioned at different angles to get several competing views like in instant replay in the NFL to help overcome some of these problems??)......so maybe the system can never work???......Do we need such sophisticated timing systems anyway???.....It depends on things like whether or not people as a whole really care about "ties" and things like that....what if 4 of the 8 swimmers in a short race all have the exact same time to within 0.01 seconds sometime at a later Olympics?....Does anyone care if they all share the gold medal??....I know I don't care.....I'm just arguing that the technology for a timing system that is reliable enough and can discern times on a scale of 0.001 seconds is "feasable"...that's all!! www.olympusindustrial.com/.../1 newmastersswimmer

One of the points that is stressed in introductory lab courses, is that you report a meaningful number of significant digits, compared to the precision of the measurement. If you are traveling from coast to coast by car, you mention the distance in miles, you don't bother to report an odd number of inches. With hand timing, the human reaction time is about a tenth of a second. (I knew Psych 101 would come in handy some day...). Even though your hand watch has more precision, it makes no sense to go to greater precision than 0.1, based on the human element. With video and electronic timing, the precision is better than 0.1 seconds. Knelson worked out that 0.01 seconds is a little less than an inch, which is a noticable separation with slow motion video. I'd argue that 0.001 seconds separation would not be detectable, even with slow motion video.

Originally posted by LindsayNB If 0.01s corresponds to a distance of about 0.02m then 0.001s would correspond to 0.002m or 2mm. Unless your slow motion video was very high resolution, had a very high frame rate, and zoomed in to a relatively small area, 2mm would be subpixel resolution. Yes! (Unfortunately, I had to modify my post, because you beat me to this.) Originally posted by newmastersswimmer it's how they can tell "almost" exactly when a ball hits the ground on a serve to see if it is actually in or out. There is absolutely NO doubt that there exists video technology that can determine who touched the wall first between two swimmers in the same heat whose times are no less than 0.001 seconds apart. Wrong! (My opinion :D) I've watched those tennis matches as well. For most balls, I agree, they do a better job than a human observer could. But I noticed that you said "almost", because there are cases where you can't tell. (The commentators run the footage backwards and forwards several times, and disagree with each other what the right call was.) That is why in tennis, you rule the ball "in", unless you clearly see it out. (I remember reading a tennis magazine article, where they placed a ball about an inch from the line, and took pictures from around the court. The line-persons vantage point could see the ball out. All other viewpoints, including the chair umpire, player, and TV camera view, the ball looked good. And this was without ball compression.) There is significant doubt for a 2mm difference in swimming... For cameras mounted overhead, water distortion will make it difficult see a difference that small. Also, do you count the fingernail, or the (soft) pad of your middle finger? It is also a touch pad, so a small amount of compression is needed to detect contact. One swimmer might have zero separation between their finger and the surface of the touch pad, but another swimmer (who touched 0.001 seconds later) who is moving faster could cause their pad to trigger first. Just because the clock electronics can report times to a thousandth of a second (or smaller), does not indicate how reliable (repeatable) those measurements will be.

coming in late to this conversation, but there is no way (well, at a reasonable cost) a 50 m pool can be built that can guarantee that two different lanes are within 1 mm of each other. That is why races are decided to the nearest .01 second, not .001.

Well you can always argue anything you want I suppose....unfortunately the actual reality is that you are very wrong though....Even if we use the average rate of a 22 second 50 meter swim (which is faster than most of us can swim any distance at)......one can travel approximately one fifth of a centimeter in 0.001 seconds (basically one tenth of the distance knelson calculated that you would travel at the same rate in 0.01 seconds). You don't think slow motion video can detect a distance of one fifth of a centimeter??....and/or that slow motion video can't take more than one still shot picture per 0.001 seconds?.....I guess you don't watch professional tennis much...b/c they have super high speed video cameras that take something like "ten to a hundred" (or maybe more?) still shots per 0.001 seconds.....it's how they can tell "almost" exactly when a ball hits the ground on a serve to see if it is actually in or out. There is absolutely NO doubt that there exists video technology that can determine who touched the wall first between two swimmers in the same heat whose times are no less than 0.001 seconds apart. And as knelson said....in 1984, the timing system in place at the Olympics COULD also discern between two swimmers who touch the wall at two different times that are at least 0.001 seconds apart. So I guess I'm not following your argument at all....sorry...I mean no offense though! newmastersswimmer

If 0.01s corresponds to a distance of about 0.02m then 0.001s would correspond to 0.002m or 2mm. Unless your slow motion video was very high resolution, had a very high frame rate, and zoomed in to a relatively small area, 2mm would be subpixel resolution. I think if swim races get down to being decided on 0.001s they will be boring as heck to watch. I already found the 50 free at the Olympics anti-climactic, only the electronic timing system could distinguish between the top few competitors. When results get that close you really need multiple attempts to make the results non-random. What would be interesting to see would be plot of the improvements in times over the years. Is there an asymtopic limit we are approaching or is it still steady improvement.

Originally posted by LindsayNB What would be interesting to see would be plot of the improvements in times over the years. Is there an asymtopic limit we are approaching or is it still steady improvement. My theory is that there is a limit we are approaching, but will never reach (until we genetically modify ourselves).

I think if swim races get down to being decided on 0.001s they will be boring as heck to watch. originally posted by Lindsay I agree that it takes very sophisticated (and very expensive) video technology to provide video information that can discern between two swimmers who touch the wall 0.001 seconds apart......It's not necessary though b/c they have already had timing systems that can do this (as knelson pointed out).....As far as your quote above....I guess I don't really get your point there b/c it seems completely irrelevant as to what degree of precision the timing system is.....a race will appear the same to the naked eye either way won't it?....what makes a race more (or less) boring to watch then based on the degree of precision in the timing system?....(please see my message below after Mattson's in which I recant this last statement...sorry!) newmastersswimmer