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All this and I didn't link to the Time Cube
May 18, 2009 2:45 PM   Subscribe

Timepieces! Ancient calendars, ancient clocks, beautiful clocks, atomic clocks and the clocks built into your brain that determine how you perceive time and form memories. All the good stuff is inside:

How we count and perceive time is fascinating.

Very early civilisations developed sophisticated calendars: the Sumerians 5,000 years ago in what's now Iraq; Stonehenge 4,000 years ago (and more recently, ManhattanHenge); the Chinese calendar system between 3,500 - 4,000 years ago; Calendars from North American societies dating from 500BC; the Julian Calendar from 45BC; and finally our current Gregorian calendar in 1582. Much younger but arguably just as important as the other calendars is Epoch or Unix time, the common time counted by UNIX and LINUX-based computers worldwide, providing a foundation for communication across networks. (previously)

More recently, clocks have become crucial. Harrison's very beautiful series of clocks (H1, H2, H3, H4) were accurate enough to calculate longitude and opened the seas for reliable trade, exploration and systematic mapping. The spread of fast travel by rail lead to the standardisation of time zones, with towns in Britain and the USA moving from local solar time to "railway time". Knowing the right time rapidly became a commodity: three generations of the Belville family made their living by providing London's clock-owning homes and businesses with the correct time. Our best atomic clocks can now be accurate to within 1 second every 300 million years and are essential for systems like GPS and global communications. At the other end of the scale, the Long Now foundation wants to build a clock to measure 10,000 years. If you'd prefer something a little more practical, you could always get this wall-mounted 100 year alarm clock instead.

We have a multitude of different clocks ticking away inside our brains and bodies. An healthy heart, for example, will keep a steady rhythm indefinitely without any signals from the brain. Our second best-known timekeeper is the suprachiasmatic nucleus. It keeps us on an amazingly accurate cycle that averages 24h11m +- 16 minutes, keeping our bodies to this cycle even if forced to live a 28-hour day or living in a light-free cave with no watch. This 24-hour cycle controls an amazing array of bodily functions, including hormone levels, body temperature, your immune system's activity and much more. It gets re-adjusted daily by sunlight so we can trick it into adopting longer days, which will be useful for when humans get to Mars. Jet-lag sufferers (whose "deep sleep" clock becomes detached from their REM sleep clock) know that this isn't nearly enough, so will be interested that eating breakfast after at least 16 hours without food beats jet lag by immediately kicking your cycle into "morning" mode, at least in mice and one Formula 1 driver (about 50 minutes in, probably UK only). Shorter times (fractions of seconds to hours) are counted by several different systems including the basal ganglia and the parietal lobe.

The rate at which these clocks tick determines how fast we perceive the world and form memories; so by altering these ticks we can seem to speed time up or slow it down. It's well known that various drugs can affect our perceptions of time: Caffeine makes time go slower, anaesthetics make it speed up. THC can give a sense of timelessness, possibly by blocking a a clock circuit that measures time in the seconds to minutes range. Memory load, time of day and mood also have effects, but surprisingly, one of the biggest factors seems to be body temperature.

Just like in The Matrix, fear really does make time seem to go slower, letting us pick out details that otherwise we couldn't perceive. Some people claim that they've learned to exploit this in sports and actually stretch their perception of time to see the ball moving slower to get an advantage.

Finally, this is what started me down this train of thought: a thought-provoking radio programme from the BBC, in which an astrophysicist, a classicist and an author talk about what time means to them.
posted by metaBugs (16 comments total) 49 users marked this as a favorite

 
Ironically, a timeless post.
posted by BrotherCaine at 2:51 PM on May 18, 2009


What an awesome first post!
posted by Lucubrator at 2:59 PM on May 18, 2009


Some people claim that they've learned to exploit this in sports and actually stretch their perception of time...

My anecdote is purely... well, anecdotal, but the TV show Top Gear has a segment called Star in a Reasonably Priced Car, where they send a (typically British) celebrity around their test track in a Chevrolet Lacetti (or a Suzuki Liana in the earlier seasons) and then their scores are tallied and added to a big board where everyone can see their ranking.

It's very entertaining, because you get to see famous people reacting to an environment that they aren't typically comfortable in, and since it's always the same car and the same track, the differences are directly attributable to the person at the wheel.

Most people who are not professional drivers are hyper-actively excited, and they talk to themselves and swear, and have a death grip on the steering wheel, and it's great fun because we, the viewers can see these stars out of context, but doing something that we can relate to. But every once in a while, just for kicks, the show gets an F1 driver to do the course, and the differences are astonishing.

Usually the driver has one hand on the wheel, is completely relaxed, and is often complaining about the speed while making remarks about the track or the cameramen, or whatever.

It's obvious, once you notice it, that they are simply operating on a different time scale. When you get used to moving at 200 miles an hour, 60 or so probably seems like they are standing still, and under those circumstances, they can dedicate their extra perception bandwidth to fucking about.

I've never really seen a better example of this effect so clearly and repeatedly laid out. In a way, it kind of made me jealous, I'd love to be able to be so skilled that I could slow the world around me down enough to react differently and with great ease.
posted by quin at 3:28 PM on May 18, 2009 [4 favorites]


I'm waiting and waiting for somebody on the subway to point to my wristwatch and ask for the time, just so I can pull out my pocketwatch and confuse them.

...what? I like clocks, okay?
posted by lolichka at 3:41 PM on May 18, 2009


Usually the driver has one hand on the wheel, is completely relaxed, and is often complaining about the speed while making remarks about the track or the cameramen, or whatever.

I used to drive 100mph+ on freeways often, before I finally encountered a situation where even being hyper-alert was insufficient to avoid a crash (no one was hurt). Nowadays I drive ~10-15 miles over the speed limit most of the time. It drives my wife crazy, she's much happier when I drive slower, but every time I drop to what she considers a more reasonable speed, I can feel my brain shift from hyper-vigilant alertness (alpha state?) to a kind of driving trance (beta?). Paradoxically, I feel much less safe when I'm driving well within the envelope of what my reflexes can handle. I have no idea whether the science behind this description of zanshin from the Way of Kata is accurate, but it makes for an interesting read.
posted by BrotherCaine at 4:20 PM on May 18, 2009


Having accurate time is also important in some security protocols, such as Kerberos.

And of course all our computers are kept accurate via NTP.
posted by jeffamaphone at 4:23 PM on May 18, 2009


I'd love to be able to be so skilled that I could slow the world around me down enough to react differently and with great ease.

Well, there's always shrooms.
posted by jhighmore at 4:45 PM on May 18, 2009


So an an astrophysicist, a classicist and an author walk into a bar....
posted by DreamerFi at 9:31 PM on May 18, 2009


I'll feel a double ass if this is already covered in your post -- I admit I've only scratched the surface of this astounding beast of an FPP -- but my choice for "Best Theory of Time -- Philosophy or Poetry" has to go to Henri Bergson (apologies for a link to Wikipedia, but it's convenient). Musta spent half of undergrad and grad trying to crack his cone.

"Crack his cone." Heh.

Oh, let's be mature, Rob. Really.
posted by ford and the prefects at 9:51 PM on May 18, 2009


Brilliant post, first or any time. Glad you're on the blue metaBugs.

An interesting new bit of chronobiology research on the human inner time mechanism, the Circadian clock, cancer and fat metabolism; "circadian disruption increases cancer incidence and cancer growth rate; "the complex relationship between circadian rhythm disruption and cancer. The potential implications of this comorbidity for therapy and even for prevention."

Chemotherapy works better when given at the appropriate time of day. Also: "nurses who worked at night and flight attendants who continually crossed time zones had a higher risk of breast cancer than women who did not have their circadian rhythms disrupted, and that constant light, dim light at night, or simulated chronic jet lag could substantially increase tumour development."

A little soundtrack to the tick tock:

Time - Pink Floyd

Casablanca-As Time Goes By

Time After Time

The Rolling Stones- Time Is On My Side
posted by nickyskye at 10:20 PM on May 18, 2009 [1 favorite]


Al Green - Funny How Time Slips Away
Edwin Starr - Time
posted by PeterMcDermott at 12:18 AM on May 19, 2009


Darn. I've just realised that the link from "fear really does make time seem to go slower" is wrong. Worse, the story I linked to mis-reported the research. So a correction:

Fear doesn't make time go slower for us, we just remember that scary or unusual events took longer than they actually did.

BrotherCaine and Lucubrator: Thanks! I'm actually worried that it's way too long, more of a blog post than an interesting link? I've been hanging around on Ask for a little while, but definitely still a newbie here on the blue.

quin and BrotherCaine: Usually the driver has one hand on the wheel, is completely relaxed, and is often complaining about the speed while making remarks about the track or the cameramen, or whatever.

I juggle a lot and frequently teach beginners. Learners often complain that everything is going too fast for them, that they don't have enough time to watch what's going on and correct for their mistakes. When I juggle the same pattern (3 ball cascade) I feel like the balls are moving through treacle and that I almost have time for a sit down and a nice cup of tea between each catch. This is something that has developed over almost 20 years of practising more difficult patterns, in which my hands and eyes have to move faster.

I've no idea whether this is due to a difference in time perception or just whether I'm looking for different things than the beginners. I think, for example, that beginners try to watch the path of the balls when they're landing and consciously direct their hands to catch it. By contrast, when I see the peak of a ball's path I know where it'll land, so I stop watching it and my hand moves to catch it without any conscious thought. So maybe each catch just requires less of my attention, so I have a lot more mental free time between them? I can't think of a good way to test this.

The same might be true of the fast drivers. A F1 driver must be much better than most at judging road position, how a car will respond, etc. As a consequence, a lot of the business of driving will be taken care of by a sort of "muscle memory" (properly called "procedural memory", I think), leaving their concious minds free to gossip, just as we can chat while going through the complex but well-rehearsed moves of tying your shoelaces. Or maybe their bizarrely fast reflexes and decision making really are signs that time just seems to flow more slowly for them?
posted by metaBugs at 6:07 AM on May 19, 2009


There is a museum in Greenwich England that has crazy cool & beautiful clocks.
posted by jstubblefield at 7:41 AM on May 19, 2009


metaBugs : ..."procedural memory"... bizarrely fast reflexes and decision making...

I'm sure you've nailed it and it's a bit of both; the fast reflexes having been essential in becoming successful drivers (or jugglers) allowing them the necessary practice to master the muscle/ procedural memory. Regardless of the mechanism that made such a thing possible, the end result is someone who appears to be able to react at a speeds which seem unthinkable.

Though from a purely sciencey standpoint, it might be fun to stick them in a lab and actually test their abilities and see how far above the norm they actually deviate from when it comes to reflexes.

(Though I swear I did read a study that tried exactly this and it found that their reflex times were better than the average Joe, but not significantly so. It might have been pilots and not drivers though...)
posted by quin at 7:53 AM on May 19, 2009


Learners often complain that everything is going too fast

Tibetan proverb, phonetically: Gom na lawar migyur we, ngo day khangyang yeu ma yin.
A surface meaning: once there is familiarity, things become easier.

With familiarity the main chores or aspects of a task do not require such intense focus and attention as they do at the learning stage, because a skillset has developed with training over time to deal with the procedure.

Once the procedure has been learned with skill and familiarity is achieved, time can be spent putting the focus elsewhere, so the appearance is for the skilled person that there is much more time than for the beginner.

"we could never perform skills fast enough if they were under conscious control. As we acquire a skill, the declarative information we learn (‘use your little finger on the “a”; the “s” is next to the “a”; the “d” is next to the “s” ’ etc) is transformed into so-called “procedural rules”, which are completely internalized, beyond our conscious manipulation. This greatly reduces the involvement of working memory, and protects the skill from the types of interference that other types of memory are vulnerable to."

Neat new vocab of the day, procedural memory.
posted by nickyskye at 9:48 AM on May 19, 2009


Can time slow down - an intriguing experiment in time dilation featuring a flashing watch and a bungee. Also more tranditional doping up of mice.
posted by MetaMonkey at 10:42 AM on May 19, 2009


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