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# Time: An Underated Unit of Measure

Posted December 26, 2012 12:00 PM by HUSH

To continue with the sensibility of holiday themed posts, let's take a short look at New Years.

See it? Ok, that look was long enough. Unless I'm actually watching a title fight between the 2013 baby and the 2012 old man, I think that small glance exceeded my patience of this holiday called "New Year's."

I reckon my low tolerance of this holiday comes directly from the arbitrary nature of time overall. It is by far the most indiscriminate unit of measurement. It has no constant quantity, yet it is perceivable by just about every cognitive being and it helps define everything we do. Interestingly, time is largely considered undefinable, as accurately describing it requires a preconception of event order.

Anyway, let's get on with this examination of time. And for the record, this has nothing to do with The Time, the best band ever. Don't you ever say anything bad (strong language) about Morris Day and The Time!

The best operational definition available would probably be that time is a unit represented by a cyclical event. If there was no such thing as 'night,' we would have nothing to contrast with 'day', and therefore we would have no days, weeks or months. Yet, even if the night/day paradox took exceptionally longer than they do currently, we'd still have a repetitive unit which we can count that provides us another representation of order. Another example would be the pendulum of a clock ticking away seconds, Yet unlike days or seasons the pendulum is a man-made institution and it uses midnight as its reference point-but midnight is again a human construct. This is the problem with defining time as it is constantly at odds with itself.

Calendars in ancient periods were imperfect; seasons floated through the 12 proposed months because they had trouble calculating one completion of Earth's orbit, and when things got confusing (because people relied on these for harvests) societies would add a thirteenth month or hit the reset. Today's standard calendar, the Gregorian calendar, was proposed by Pope Gregory XIII to account for the error of the Julian calendar: one Earth orbit takes 365.2425 days-not 365.25. After 1,500+ years of using the Julian version, Holy dates had been misaligned by ten days. Christian nations shortly adopted this calendar and as European imperialism spread this calendar gained prominence. By the time Russia and Greece finally adopted this calendar in the 1920s, a full 13 days had to be struck from their first year to catch up. Though many other calendars retain cultural significance the Gregorian is widespread today.

Of course, we can't have any unit of measure without ISO getting involved; so in 1988 they published ISO 8601, which standardizes international dates, times and their numeric representation. The time as it would be represented, right now as I write this, would be 2012-12-20T011:09:32Z--the 'Z' representing observation of Universal Coordinated Time (UTC). This is the average time represented by 70 atomic clocks located around the world, but it also incorporates 'leap seconds' to account for the Earth's slowing rotation. The last one was added in June 2012, and for one second time was withheld from proceeding.

While UTC is accepted worldwide, it does not help the subjectivity of time. Pilots use a 24-hour system to ensure appropriate time keeping even when flying across time zones. In 1754, French mathematician Jean leRond d'Alembert proposed decimal time, whereas a day takes ten hours, an hour lasts 100 minutes, and a minute lasts one hundred seconds. It was furthered in 1788 with a ten day week and a ten month year. The French Revolution issued a compulsory decree where the country would switch to decimal time in September 1794. Decimal time lasted a whole eight months before being abandoned in the same legislation that instituted the metric system as France's units of preference. Unix time began January 1, 1970 and is measured strictly in seconds. It is helpful in some Unix-based computer systems, and the current Unix time is 1355945070.

Further time ambiguity is encountered during space travel. Here we encounter Albert Einstein's Theory of Relativity. Each location in the universe is connected and can be traversed to by going up/down, left/right, or forward/back. But these locations are also connected on a timeline so there is another method of reaching them. It is this theory that leads to our best attempts at time travel. Check out this video for more information on wormholes and how they would work. Check out this video to see how Marty McFly and Doc Brown travel time. Check out this video to see how Bill and Ted accomplish this (actually, also by wormholes).

Astronauts and cosmonauts, upon returning from space, have actually aged less than their mission control staff, though just fractions of a second. At speeds comparable to that as the speed of light, time slows in comparison to an identical, stationary measurement. This furthers the Theory of Relativity; to an individual travelling at or near the speed of light, time and the person's sense of time never change. The same is true for a stationary observer. Yet when the traveler returns to his stationary counterpart, he finds that decades have passed, when he only sensed a few minutes; and both measurements of time are correct. Why? The Law of Invariant Light Speed indicates that the speed of light is always the same. Consider this video, where a light clock does a good job illustrating the increased distance visible light must cover while moving at extreme speed. Since the speed of light never changes the only way to compensate this change in light reflection is via an increase in time increment. It's important to note that this is only noticeable when compared, as both the traveler and stationary observer will not notice any difference and both are correct.

I write this sentence just upon the cusp of December 21 (though it won't be posted for yet a week more), a date in contention for being the end of the world. Why? Because some lazy Mayans made a calendar that stopped on that date, but by now archeologists have found another conflicting version. I don't think the world is going to end in a few hours and reports from New Zealand and Australia have been encouraging, but there is a chance tomorrow could be that day. If it is the apocalypse as foretold then you probably won't be reading this post anyhow, which also means that this could be one of the last records of human history, which means aliens may carry on my words for centuries. I better come up with something substantial then: "Be excellent to each other…and, party on dudes!" After all, it is New Year's (supposedly!).

Resources

Images credits: Keybar; MP Christianity; Wikimedia; Newspaper.li; Nathan Lee; Meme Generator

Quora - Why does time slow down as you approach the speed of light?

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#1

### Re: Time: An Underated Unit of Measure

12/26/2012 8:21 PM

That's what causes time to fly: underrating (or undereating) it.

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#2

### Re: Time: An Underrated Unit of Measure

12/26/2012 10:34 PM

I do not understand why you consider time as underrated. It is the one metric that all other metrics are compared against.

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#3

### Re: Time: An Underated Unit of Measure

12/27/2012 12:14 AM

Isn't time kind of relative?

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#4

### Re: Time: An Underrated Unit of Measure

12/27/2012 12:16 AM

Leave my family out of this.

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#5

### Re: Time: An Underated Unit of Measure

12/27/2012 2:04 PM

Nice pictures!

A technician I knew was working on electronic counters. They had a period mode (1/F). He remarked "Why would anybody want to measure period? Everybody knows it's 28 days."

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#6

### Re: Time: An Underated Unit of Measure

12/28/2012 3:45 PM

The Rabbi Hillel was challenged by a barbarian chief to teach him the Torah "while standing on one leg". When I first saw this, I was young enough to think it was bloody stupid, later, the more mature me realized that without clocks, they had to use a description of an event that used approximately the time they wished to indicate.

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#7

### Re: Time: An Underated Unit of Measure

06/18/2013 2:12 PM

Underrated by whom?

It is one of the fundamentals in the metric system.