If you happen to live in the UK (or someplace that gets BBC 2), then you should watch Brian Cox on the show "Horizon" tonight at 9:00 p.m. He’s a gifted speaker, and the topic is the nature of time. I live here in the Colonies, so I’ll miss it, but I’m hoping to catch it on the web somehow (I also have a couple of moles in England who send me stuff sometimes, too).
In the meantime, here’s the trailer for the show.
If the music sounds familiar to some of you, it’s from Doctor Who. That already makes me want to see the program. And, of course, some of you might want to see it because Brian has a certain, um, appeal to a lot of folks. I just like the topic, and Brian himself, so I’m looking forward to watching this when I can.
Tip o’ the bowler hat to Gia.
December 2nd, 2008 at 8:58 am
Dr. Plait, could you post the stuff your spies send you? I don’t have as many connections on the isles as you do.
December 2nd, 2008 at 9:00 am
So is there no way for us in the colonies to watch this? Maybe you know about it airing sometime later on for us??
-Steven
December 2nd, 2008 at 9:02 am
Don’t you just love the Britsh Broadcasting Corporation? Just when you think TV cannot become any more bubble headed they spit out something that restores your faith. I’m on a night shift tonight so I’ll have to get it from the BBC site at a later date.
December 2nd, 2008 at 9:08 am
Thanks, so much for the plug, lovely Phil!!
This *will* be airing in the States at some point on either Discovery or the Science Channel – I’m not sure which. If it’s anything like Brian’s Horizon on Gravity, though, it will be edited differently for the States… I’m sure it will turn up on Google video at some point…
Or, of course, you can use a proxy to look like you’re coming in on a UK IP address and watch it on the BBC’s iPlayer from tomorrow…
December 2nd, 2008 at 9:11 am
Thanks for the tip! I won’t miss it tonight.
(Fortunately in Holland we are blessed with the BBC
)
December 2nd, 2008 at 9:18 am
A certain appeal. Um. Yes.
I’ve been meaning to splice a patch to my neighbor’s cable line….
December 2nd, 2008 at 9:50 am
I’ll be watching in hope – Horizon has really gone to the dogs in the last few years. Hopefully they’ll manage not to wreck it…
December 2nd, 2008 at 10:39 am
I say time doesn’t exist. It’s not “physically real”. It’s a measurement we make just like a mile or a pound(lb). We humans invented the concept. It’s an illusion that we’re only consciously aware of. As the woman in the video mentions, there’s no clock in the sky that ticks down continuously.
December 2nd, 2008 at 10:49 am
Looks very interesting so I’ll be sure to watch it (I can do my ironing at the same time, yay multitasking), plus I liked the Doctor Who music in the background.
December 2nd, 2008 at 11:31 am
Any UK people who can’t catch it tonight can watch this again on the BBCs website for for up to a week.
December 2nd, 2008 at 11:48 am
It’s a measurement
A measurement of what, though?
December 2nd, 2008 at 12:00 pm
Booked in on my DVR.
December 2nd, 2008 at 12:05 pm
Awesome, I will be watching this.
December 2nd, 2008 at 1:09 pm
Time is Nature’s way of keeping everything from happening at once.
(What time is it? 9PM on 12/2/08 – American style dating)
J/P=?
December 2nd, 2008 at 1:33 pm
Okay, because it’s been lingering in my mind since my friend sent it to me, and it relates to the topic of time as seen in the clip:
http://www.youtube.com/watch?v=HvgwR9ERCBo
Rob Bryanton describing the 10 Dimensions in a way that even *I* can understand. Sort of. I though of BA when I watched it.
December 2nd, 2008 at 1:34 pm
Does anyone need it? if so i’ll provide a link.
December 2nd, 2008 at 2:11 pm
Does anybody know – has the BBC ever made DVDs of Horizon available? I can’t find any mention of such a thing online
December 2nd, 2008 at 2:27 pm
“I’ll be watching in hope – Horizon has really gone to the dogs in the last few years. Hopefully they’ll manage not to wreck it…”
It’s certainly true that Horizon is generally rubbish, but the ones Cox has presented over the last year or so have been much, much better.
So far (halfway through) it’s mostly been about chronology rather than time per se.
December 2nd, 2008 at 2:37 pm
“What is time? It’s just one damm thing after another.”
December 2nd, 2008 at 2:52 pm
I was under the impression that Kant settled this issue once and for all when in 1754 he wrote his prize winning essay on the lengthening of the day and the retardation of the rotation of the Earth due to gravitational tidal forces. I guess no one has been paying attention to philosophy for the past 254 years.
December 2nd, 2008 at 2:59 pm
Just finished watching it (I’m in London on business this week – Lucky Me!™).
Why is it that, to me anyway, science seems to ask the most profound questions and demonstrate the wonder of it all, the “exquisiteness” of life (to paraphrase Carl Sagan) far better than any new-age, pseudo-nonsense can possibly do?
Oh yeah, but this science stuff — it’s real and it’s based on that, what it’s called…. oh yeah, evidence (though I’m not entirely sure about the string theory part.
Mind blowing. Watch it if you can find it online!
Brian Cox rawks!
And, oh yeah, Dr. Cox wound up asking FAR more questions than he answered. I LOVE IT!
December 2nd, 2008 at 2:59 pm
Im 16 and very big into physics. I have a theroy on a different type of(brain world). But for this to work i need to know, is it possible for somthing to erupt or exsplod inside an atom without the atom walls breaking. Get back to me if u can…..
December 2nd, 2008 at 3:06 pm
That was very interesting! I’m even more confused now about the concept of time than I was before, but then that’s probably a good thing
.
I didn’t know Brian Cox, but he rules.
December 2nd, 2008 at 3:14 pm
Stripping away the basics, time is man made.Therefore time does not exist.
December 2nd, 2008 at 4:05 pm
OilIsMastery, I have no clue what you’re talking about. What does the slowing of Earth have to do with the nature of time?
December 2nd, 2008 at 4:35 pm
Phil, if you have no idea what I’m talking about perhaps you ought to learn who Immanuel Kant is and how he made one of the most astonishing scientific discoveries in history, the retardation of the rotation of the Earth and the lengthening of the day.
Time is measured in days. Well, the day is getting longer.
As Kant proved beyond any reasonable doubt in 1754 and more widely in 1781, Aristotelian/Newtonian “absolute, true, and mathematical time” does not exist.
Therefore time is the a priori form of our intuition and not a thing in itself as claimed by Einstein and relativity.
See here: http://www.newscientist.com/article/mg17623704.600-windup.html
December 2nd, 2008 at 4:48 pm
Wow, OilIsMastery, you’re way way off base here.
Time is not tied to days. Time is independent of the Earth entirely. The day is a convenient unit of time, and that’s all.
We’ve known of the slowing of the Earth’s rotation for some time, yes. I’ve written about it extensively myself. But that has nothing at all to do with relativity. The length of the second, for example, is defined by the vibrations of the nucleus of the cesium atom, and that doesn’t change (which is why it was chosen).
December 2nd, 2008 at 4:50 pm
What is today, troll day.
December 2nd, 2008 at 5:08 pm
Phil, if you don’t measure time in days, then what unit do you use to measure it?
Seconds? They have their own problems:
McCarthy, D.D., Precision Time and the Rotation of the Earth, Transits of Venus: New Views of the Solar System and Galaxy, Proceedings IAU Colloquium, Number 196, 2004
McCarthy, D.D., et al., The Physical Basis of the Leap Second, The Astronomical Journal, Issue 5, Nov 2008
At least Brian Cox agrees with me.
“I can’t even tell you at the moment what ‘at the moment means.’ Even momentarily.” — Brian Cox, physicist, 2008
December 2nd, 2008 at 5:13 pm
Oil, do you understand the difference between time itself and the way we measure it? I don’t think you do.
December 2nd, 2008 at 5:20 pm
Phil, how do you measure this alleged “time itself?” Who determines it’s absolute measurement, on what planet, and based upon what unit?
December 2nd, 2008 at 5:33 pm
click my name how feel about OilIsMastery comment.
December 2nd, 2008 at 5:53 pm
David, this is a science blog not a feelings blog.
December 2nd, 2008 at 6:24 pm
this professor Brian sure looks appealing to me.
no BBC 2 here in Brazil either. too bad. i simply love a good look physicist… (married to one)
December 2nd, 2008 at 7:09 pm
Damn, I wish this showed in Australia. (…Does it?)
And they used All The Strange Strange Creatures! AWESOME. *puts DW s29 soundtrack on*
December 2nd, 2008 at 9:07 pm
OilIsMastery, I strongly urge you to read some basic texts about Relativity and the nature of time. You’re talking about how to measure it, but what we’re talking about here is what it is. You’re mistaking a container for the substance itself.
December 2nd, 2008 at 9:25 pm
Phil, I strongly urge you to read the Critique of Pure Reason. There is no “absolute, true, and mathematical time” (Newton, 1687) unless you beleive in God and angels like Newton did.
December 2nd, 2008 at 10:07 pm
The length of a day the amount of time it takes for the sun or some other celestral body to move from a point to another point in the sky. This is due to the planets rotation of the Earth around its axis. Over the years due the influence of the moon the rotation has slowed down. The length of a year is the amount of time for the Earth to go around the sun once and is actually 365.256363 years. Every 4 years we ad and extra day and every 400 years we skip the leap day but once and while our clocks are out whack for a second so we add a second.
Now imagine a train that has two panels and a ball. If you throw the ball at the speed of light (representing a photon) at one panel, the ball will bounce back and forth in a straight line. But if the train speeds up to the speed of the light the ball will appear to travel in more of trianglar path and thus it appears it takes more time for the light to travel but since nothing can travel faster then light then it took longer for time to pass from the perspectice of a person not on the train but from a person the train the path is same and the ball just go back and forth in a straight line. hence it is relative to where the obsever is.
Another wee comment OilISMastery do have any references from like the 20th century?
December 2nd, 2008 at 10:33 pm
Part 2
Now let us imagine a space capsule. And across the inside there is laser that goes from onside to the other in a straight line when it is at rest far away from any other body. Now acceralate the capsule at say 1g after a while the capsule will getting closer to the speed of light. From an outside observer the beam of light will appear to be bent. Now put the capsule in a gravity field of 1g, again from the the outside observer the beam will appear to bent, and exactly by the same amount as it was when the opject was being acceralated by 1g without the gravity field. And since the distance has not changed and the speed of light has not changed therefore time and space have changed.
So days, years and etc are just units to measure time and are completely man made. When objects are travelling at the speed of light or in a gravity source time inside the object appears to slow down from an outside observer.
December 2nd, 2008 at 10:48 pm
To David, in response to “do you have any references from like the 20th century?”
If you actually read what I wrote instead of ignoring it you would know the answer to that question. Does McCarthy 2004 and 2008 ring a bell? Reading comprehension difficulties?
All time is man made. There is no such thing as absolute time unless you believe in God and angels like Newton did.
December 2nd, 2008 at 10:54 pm
Sorry I forgot about the McCarthy papers, busy night here at work, but I still agree with Dr Plait you have some serious problems with the workings of time.
December 2nd, 2008 at 10:59 pm
Hey Phil, are you saying that time is a substance. What substance would that be? The measurement is time itself. When I say “what time is it?”, I’m referring to the measurement of the Earth’s rotation. Time is a measurement of motion(Phil’s example vibration of an atom). Even without being on earth or any planet, time is still a measurement of something. I think I understand and agree with OilIsMastary.
December 2nd, 2008 at 11:18 pm
OilIsMastery:
“Time is measured in days. Well, the day is getting longer.”
This isn’t even coherent. If time were only man-made, and it were measured in days, then, logically speaking, every day must ipso facto be exactly 1 day long. And the days are getting longer, you say? How?
One of the two statements must be false. I choose the “time is measured in days” as the false one.
As for precision, atomic clocks are extremely precise. But there are theoretical limitations to their precision. Regardless of this, it’s possible to keep time more accurately, ironically, by using atomic clocks–you simply use a number of them and take the average.
As for absolute standards of time, you’re right, but everyone here knows that. Time is relative; the passage of time depends on the relative velocities, accelerations (gravity well placement certainly counts), etc of relative observers; as far as we’re aware, it does this according to the laws of General Relativity. Then again, its very doing so seems to turn your notion that time is man made on its head (the hell with Kant–or at least your naive interpretations of his Critique of Pure Reason).
That there is a sort of consistency with the measurement of the passage of time, that this consistency betrays mankind’s personal conveniences and order, and that all physical phenomena as far as we are aware behave in terms of rates of change in very precise ways, are all major clues that there’s something to this whole time thing that is independent of mind. There’s no possible better way to express this general notion of universal symmetry of physical behaviors that I’m aware of other than to just say, time is real.
None of this tells us what time really is, or distinguishes or confirms our psychological notion of time from the objective fact of time. That’s what Brian Cox was on about.
Oh, and what Kant was on about is best summarized by the freaking title of the treatise–A Critique of Pure Reason. Kant wasn’t denying the existence of time either, but rather, the ability of mortals to sit down with pen in and and lined paper, by writing things down that “must be” according to one’s intuitions, to divine its secrets.
December 2nd, 2008 at 11:40 pm
I’m not smart enough to really figure out the actual science (but I do enjoy trying to learn it).
But it appears a lot of the above comes from using time in two different meanings, form different points of knowledge. Queue the old “It’s only a theory” type of saying via people badly debating evolution.
There’s “Time” being units used to count the passage of, well… er, time! Seconds, Days, Months, what have you.
And Time being the mechanism behind such units. This program is not showing in my region of country Australia alas.
I do admit I could be greatly onset of wrong. If the science channels here would do something better than Nazis and UFOs I’d probably be a little smarter.
December 2nd, 2008 at 11:48 pm
For all you Dr. Karl pod cast listeners out there, the conversation here got echoes of Tetrahedron Girl.
December 3rd, 2008 at 3:05 am
I watched this last night and really liked it, they covered a lot of things quite comprehensibly (though they could have covered the Planck length a little more extensively, instead of only saying that’s when our understanding of time stops), though two things stuck with me:
1) At a certain point they arrive at the conclusion “time has always existed”. Isn’t that a truth by definition? Since “always” is a measurement of duration, isn’t that like saying “time has existed for as long as it exists”? I understand what they were getting at (questioning the limit of 13.7bn years since the “beginning of time”), but I found that kind of a poor choice of words.
2) If the passage of time is relative to the speed you are traveling in through space (I liked BC’s analogy of using some part of you speed-of-light-travels through time in order to move through space), then how do you measure the speed you travel with? You could say that someone who is running is moving faster than someone who stands still, but what if that person is running opposite to the earths spin? Wouldn’t he go slower than the person standing still instead? And since the earth orbits the sun, and the sun isn’t stationary either (etc, etc..), do the speeds with which these objects move need to be factored in too? And how is this speed determined? Or asking this question a bit more abstract: How can you measure distance in a universe that doesn’t seem to have any fixed point to use as reference?
By the way, we need more people like Brian Cox, he really helps me and others understand science and makes the complicated stuff way more accessible. I’ve been listening to his CERN/LHC podcasts for a while now (one of the episodes features Phil), and I’d recommend them to anyone interested.
December 3rd, 2008 at 3:27 am
“If the passage of time is relative to the speed you are traveling in through space (I liked BC’s analogy of using some part of you speed-of-light-travels through time in order to move through space), then how do you measure the speed you travel with? ”
Your time is constant for you, no matter what speed or direction you’re going in. It varies for other observers, based on their motion relative to you. And vice versa. You don’t need to measure against the universe (although if you did, it would be against the distribution of all the matter (and dark matter) in the universe).
December 3rd, 2008 at 3:51 am
Google video often has plenty of recent Horizon episodes if you want to watch it that badly. Should be on there eventually. The other most recent Brian Cox episode went up, so this one should too.
Never fear, google is here.
December 3rd, 2008 at 4:24 am
I agree with Sander, Dr Cox (and others like him) really do make quite complicated concepts accessible. This p;articular broadcast made me think of quite a lot of things.
For instance, when they were discussing Einstein’s idea of time and how it could be completely analogous to space in its properties, I (and no doubt many others) was groaning and thing “The woos will love this – it appears to validate all their dammed ideas about clairvoyance and prediction!”.
Then Cox came to my rescue with another concept of the nature of time, the one about ‘granularity’. And as he said, it actually ‘felt’ right; I found myself nodding along in agreement. And yet I couldn’t explain why it ‘felt’ right – it just did. Yet no doubt the woos find that Einstein’s straight-line, everything- exists-at-once concept ‘feels’ much more right (trust me on this – I was a woo once).
So. I started thinking about the whole idea of peoples’ differing world-views. I didn’t come to any shattering conclusions. Just rounded off the evening with a damm good thinking session. Basically, all I have to say is – hooray for people who make you think!
December 3rd, 2008 at 5:11 am
One word: UKNova (http://www.uknova.com/wsgi/info/view/10)
December 3rd, 2008 at 5:27 am
has anyone got any links about the stuff concerning time being “built up like grains of sand”? I’d like to find out more, and I was momentarily (geddit?) distracted when the scientist was being introduced.
my guess is that if there’s an arrow of time anywhere it’ll come out of quantum measurement – assuming we crack the measurement problem that is. Whether you favour decoherence, waveform collapse, bifurcation of many worlds or other ideas, they certainly look like time-asymmetric processes to me. (disclaimer: I don’t understand the maths, though, so if I’m wrong please disabuse me)
December 3rd, 2008 at 7:13 am
Has anyone been watching Catastrophe on channel 4? It’s about the history of natural disasters on Earth and how the Earth has evolved from them.
http://www.channel4.com/science/microsites/C/catastrophe/index.html
You can watch them online aswell! Be quick though, they only stay up for 30 days!
December 3rd, 2008 at 7:29 am
Thanks Ginger, that’s something I can work with
December 3rd, 2008 at 10:45 am
Motion and change are materially real but time is not. Time is merely transcendantally ideal and the a priori form of our intuition. Again, this has been known since 1781. I guess the rotation of the Earth is not the only thing that is retarded.
December 3rd, 2008 at 11:17 am
“Motion and change are materially real but time is not.”
Unfortunately, motion, change, and even my own a priori reasoning, have absolutely nothing to do with my arguments for the existence of time. (Neither does your ad hominem, argumentum ad antiquitatem, or false appeal to authority).
December 3rd, 2008 at 1:05 pm
OilIsMastery, I would hope that all of us are intelligent enough to a)discuss our opinions in a sincere and composed manner, and b)refrain from childish insults. I was interested in the theories that you were sharing, in philosophy and as well as in science, but you’ve turned me off completely if you’re going to be that petty. For shame.
December 3rd, 2008 at 4:09 pm
Missed this yesterday but I just watched this on the BBC iplayer.
http://www.bbc.co.uk/iplayer/episode/b00fyl5z/b00fyk8c/Horizon_Do_You_Know_What_Time_It_Is/
Fantastic watch.
December 4th, 2008 at 1:34 pm
“The elements of the physical reality cannot be determined by a priori philosophical considerations, but must be found by an appeal to results of experiments and measurements.” — Einstein, Podolsky, and Rosen, 1935
What unit of measurement is that again? Days or seconds?
December 4th, 2008 at 1:54 pm
The program was entertaining but enlightenment was on the level of statements like “We fly through time at the speed of light”.
For a mixture of deeper and weirder ideas about time try the FQXi essay contest on the nature of time at http://fqxi.org/community/forum/category/10 where you can now vote for your favourite entry.
December 4th, 2008 at 10:41 pm
OilIsMastery:
WRT the quote in your last post… sure. I buy that completely. Note that it conforms completely with my arguments above–it’s not a priori, it conforms to experiments. (It also coincidentally agrees with what Kant really said, but mind you, Kant’s allowed to be completely wrong).
Note however that making the a priori claim that time does not exist flies in the face of this quote.
Regarding this: “What unit of measurement is that again? Days or seconds?”
…not sure what you’re referring to. My point above was that it’s logically contradictory to claim both that the day is getting longer, and that it’s the way time is measured. Days getting longer simply means that the time span (i.e., time measure) of a day is increasing with respect to a time metric. If you define time in terms of the day, it’s always 1 day long. It can’t get longer than 1 day long by definition.
December 6th, 2008 at 7:57 pm
Does anyone know where I can get a 3D animation video, online, of the Hubble animation that Steven Beckwith presented to Brian Cox about 20 mins. into the show?
December 9th, 2008 at 2:30 pm
Just caught this on BBC Iplayer.
Excellent programme and sadly beyond what classes as “normal” TV these days.
Hope they release it on DVD.
December 30th, 2008 at 9:49 pm
[...] tip to Phil Plait for telling us all about the show, some time [...]