People say that we are all time travellers because we move through time at a rate of 1 second / second.
I pointed out in my definition on what is time travel that this is not the case…if time is like a river and we sit on a boat floating on that river, we have an analogous case – we flow down-stream but we’re not in control. We drift; we don’t travel (except relative to the river bed).
A friend pointed out that maybe describing time as a river isn’t strictly correct. According to the general theory of relativity (GR) time is relative and should be viewed on a local scale, whereas the picture of a flowing river is holistic (and therefore not covered by GR).
However, the counter argument is that the river of time can be viewed – or indeed changed – on a local scale. A sand bank, or a large fish can locally affect the flow of water.
And as a colleague pointed out – as in GR, a moving fish can eat a smaller fish and gain mass.
“It makes sense” he added. “When I’ve eaten a large lunch my perception of time definitely changes.”
I don’t think much more can be said on that subject!
At least, this is my cover story for watching “Dora the Explorer’s Ballet Adventure” last night !;) (This post isn’t a plug by the way!)
The main ‘plot’ is that the delivery duck delivered the wrong package to Dora and her friends just before they were about to perform a dance show; he delivered scuba flippers instead of dance slippers.
Dora’s mission was to leave her friends to go to the dance school, collect the dance slippers and bring them back in timeso that the dance show could go ahead.
I know that the DVD is aimed towards young children, but I must admit that I was hoping it was also aimed for their parents who might be interested in time travel!
I can’t help wondering if our perspective on direction – including time’s arrow and direction of the flow of time – needs a little readjustment.
In this post I commented how we often tend to think primarily in the spatial direction before the temporal field. My daughter already tries to turn that on it’s head, and at times thinks Outside the Temporal Box.
Here’s another a conversation I had with her a few nights ago when I was reading her a bed time story. Whilst not technically related to time travel it’s perhaps an initial start to getting thinking more openly about direction:
Daughter: “Daddy, you’re reading backwards!”
Me: “No I’m not! I’m reading forwards – see?”
I fan the pages in a visual effort to explain.
Daughter: “But that’s the back over there.”
She’s pointing to the back of the book – the part where invariably in stories for 4 year old girls the princess lives happily ever after.
Me: “Yes, this is the front [pointing], and this is the back. So I’m reading in this direction.”
Daughter: “That’s what I’m saying, Daddy. You’re reading backwards to the end!”
A lot of people think that the first time travel novel is The Time Machine by H. G. Wells, published in 1895.
Aside from the fuzzy logistics of what “being first” really means in time travel, the above statement is incorrect. Indeed, H.G. Wells had already published a short story called The Chronic Argonauts in 1888, thus scoring an own-goal in beating himself to the title of First Time Travel Author.
A little less self-plagiaristic is The Clock That Went Backward, a short story by Edward Page Mitchell which was published in 1881, and as far as I can tell, the ‘first’ piece of fiction involving time travel.
I’ll get round to reviewing it later, but the point I wanted to make is that the story is set in Holland; a small country with a complicated language. I can’t help but wonder why Holland was chosen as the setting for this ground-breaking piece of work!
Yes it’s true…the time2timetravel HQ is situated in Holland too, where if you search hard, you can end up in some pretty quirky places!
And there is the “Dutch clock”. I wasn’t even aware there was such a thing until they kept popping in in various novels I’ve been reading, and here was a surprise…that the picture of a clock face used as a header on this site is actually of a Dutch clock…although I hadn’t realised it when I took the picture!
(Rather ironic…I live in Holland, and took this picture of a Dutch clock during a holiday in France!)
I don’t have a picture of the above clock in all of it’s full Dutch chronological glory (…in France 😉 ) but descriptively it could be described as a short and stumpy wall mounted grandfather clock. Or at least, one with its legs cut off (see image, right).
Given the story line of The Clock that went Backward irony again hits us in the face, in that there is a Dutch saying that the Dutch people are tall so that if the sea dikes break then they can keep their heads above the water.
Tall people, short clocks. But I guess they are not the only ones short on time!
Some time ago I took a short break to Texel – one of the Wadden Sea Islands off the coast of Holland.
Quite by chance (or so I thought…) I ended up in a cafe called “De Tijd” (“The Time”).
The walls were absolutely plastered with clocks! The waitress told me that they were all gifts, donated by patrons over the years. Now (sadly) there is not enough wall space for the tradition to continue, but instead notebooks lie on each table for visitors to jot down any thoughts they might have (regarding the food they’re eating, where they’ve come from, etc.).
Above my head in the shot above is a plaque with a poem, “De Tijd”
Here’s the translation (thanks to google translate…my own Dutch isn’t up to the task!):
Whatever one does, the time passes
though it does not, time passes
whether they are impoverished or enriched
uitslooft themselves or sailing stroke
been doing it wrong, though it does well
‘t they awake or asleep, and nothing suspect
yes, which one also gets rid of
elapses from the time, time!!!
And talking of things above my head (and I’m talking quite literally here!) did I mention that the ceiling space was also used as efficiently as the wall space?
And what of the food? It was served on plates like this, which get a thumbs up from me for not displaying the annoyingly presumptiously happy ten-to-two (or ten-past-ten…)
Whilst we were waiting for the food to be prepared, my wife reminded me that we’d been here the previous year. I’d forgotten all about it! We were having about to have a ‘Deja Eat’!
So my wife as reliving her past I was living the present, and as the food was brought in, served on a time-plate, I couldn’t help thinking of Plato (sorry…! 😉 ) and his wish to remember the future.
Maybe we’ll be back next year…but I can’t remember!
I have a doppelganger. He looks a bit like me and he behaves a bit like me. But he’s not me; he’s a little taller but not as scrawny, he’s a bit less bald, and he doesn’t wear glasses. He wears a black coat as I do and slings a small grey rucksack on his back. As I do.
And he really gets on my nerves.
Like me, he doesn’t talk to other passengers on the train and avoids them by fixing his focus on glitzy but intellectually dull pages on a free newspaper. Reading about characterless celebrities with non interesting lives. Loser. At least I read books. Or write in my journal.
But sometimes he likes to watch real people.
The first time I caught sight of him I thought he was a pillock and best avoided. The trouble is that it seems he’s everywhere I am – and can’t be avoided!
He catches my train every morning. And he cycles to his office on the other side of the road as mine, pedaling the same speed as me – either just in front or just behind. He leaves his office when I do, and cycles again either just in front or just behind me, back to the train station where he catches my train to take him back to his home.
He waits on the same part of the platform every day so that he’s best positioned for his favourite seat – a single seat towards the back of the carriage where he can sit without the elbows and knees of an adjacent passenger protruding into his personal space.
I like to sit on the seat at the side with the back to the window. Many don’t like it as it means a sideways motion when travelling and that means I have space. No arms or legs or bags or large newspapers invading my personal space. And I can watch him trying not to let me see him watching me!
He observes everything with silent disdain; a scowl or disapproval of any facet of life he may encounter in his unchanging sphere. And yes, I have caught him eyeballing me too, through the corner of his eye – I have seen it!
I’ve never spoken to him, but he’s never spoken to me either. He started it.
A couple of times I have tried to make contact; to break the strange awkward aversion, but it never pans out. When I make a deliberate sustained look directly towards him, that’s when he sneezes, or reaches for his phone, or looks the other way. There’s always some excuse to not look at me directly. What am I…Medusa?
It seems that there is an unspoken battle between us, although I cannot say over what. Maybe for our very own existence.
I wonder. I read something a while ago that doppelgangers can’t share the same space or time – it is a paradox of causality. Some explain that multiple versions of a person exist in multiple parallel universes which are created at “bisection points” – when alternate outcomes of momentous or key decisions have been made.
Personally I don’t believe in the instantaneous creation of mass and energy out of nothing on a whimsical decision.
But if it were true, maybe a crossing or an intersection of these [not-so-parallel] universes would allow a person to meet an alternative version of himself? Or would interaction cause one or both of us to disintegrate? Or the universe?
I don’t know. But I do think it would be painful to find out.
(Too much) Contact
I’ve only ever seen him smile once. Perhaps. Actually, it was more of a smirk. I hadn’t seen him for a few days since the weekend. I wondered where he was because he wasn’t waiting on the platform at his usual place. He must have been ill because on Thursday he was back and letting me know about it as he was coughing loudly on the train. And he wouldn’t stop.
It was strange because he wasn’t on his favourite seat – he was sitting behind me. I bet he did it on purpose as my side bench wasn’t free and I was sitting on a regular forward facing double seat. I could almost feel his germs flying through the stuffy train atmosphere in a direct but statistically random walk to the back of my own bald head.
I stood up early to leave the train so I was facing him whilst he remained seated. He decided to sneeze at that moment to avoid eye contact, but I’m sure I saw a smile of smugness, content that he’d infected me; an invasion of my physical and personal space.
As I stepped off the train there was a cough behind me. Too close behind me. It was him.
He followed me, as he always does, on his bicycle on the way to work. Some may call it slip streaming, but I find his close proximity disturbing. Shadow cycling. He was right there by the mudguard of my back wheel…so close I could hear him sniffing.
I increased my speed, and he matched it. I slowed, as did he. Why won’t he just overtake me? In desperation and frustration I weave from side to side in a futile attempt to shake him off. Get in front! S**t before shovel!
But I couldn’t get rid of him. I never can. He’s always everywhere I am.
All the time. Day after day.
Another day. Another time.
It’s another day and I’m on the train again. I’ve forgotten my book and I have nothing to read. I’m bored. I need to do something to pass the time on this hour long train journey. Lying nearby is one of those ridiculous free newspapers. I thumb through a copy, bored as hell, but there’s nothing else to do.
I glance at a few other passengers but they’re immersed with their phones. One is making notes and looking a bit peeved about something. I’ve seen him around quite a bit. He’s always looking at me. Must be a nutter, so I try to avoid him.
I’m not feeling too well, I think I picked something up from some cretin in the train. And I think I know who. The last few days I’ve stayed at home; he’s probably aware of that and noted it down in his journal. But today I’m feeling a bit better and I’m back, but this stuffy air in this carriage isn’t doing me much good. It’s busy today, God knows why, so I’m sitting in a regular seat and already I’m blocked in and I can’t get up to walk to the train entrance where the air is fresher.
It’s a really tickly cough that won’t go away. If I talk, it gets worse. I can’t get out.
He’s come and sat in front of me now. He’s always around. I can’t get rid of him.
Argh. I’ve got nothing to do! I’m so bored. I can’t even look through the window as my seat is by the broad metal window frame. I can look forwards at the back of the chair in front. That’s it.
I’ll check my phone; it has pictures of my wife and girls. They cheer me up. I’m looking down at my phone. I’m trying hard not to cough but I need to sneeze. I can’t sneeze looking down, but as I inhale and look up he’s standing in front of me. He’s always there! Wherever I am! No matter. It’s my stop, and I can lose him. Besides, my wife loves me. So do my girls. I smile at the thought and stand up.
When I get my bike from the bike shelter he’s there, looking at me. I always think he’s going to say something to me, but he never does. It’s very awkward.
Thankfully he’s in front of me. I hate it when he’s behind me; I can feel his eyes bore into the back of my head. But it’s difficult with him in front too. He wobbles, and does unpredictable things. I’ve tried overtaking him, but he speeds up! In desperation I free wheel, but he slows down! Anyway, I guess I’m still recovering – I feel weak and my nose is running.
I want to overtake him; to pass him and get shot of him, but I can’t. He wobbles all over the place making it impossible for me to do so.
He’s in front of me again when I cycle home from work. I’m tired and not in the mood for this nonsense. He’s tailing me again. I’m nearing the end of my journey. I’m approaching the level crossing near the bike shed where I’ll leave my bike and catch my train home to my girls.
It’s not far to go, but now I’ve had enough. I’m running late, and maybe I’ll miss my train. Surely it’s close. I urge the rubber of my front tyre to touch his back wheel – he can’t avoid me now!
I call out. I can feel the pressures of two parallel universes twisting and contorting, striving to make contact at a single moment in time, at an elastic point in space.
Let me pass!
He looks behind, glaring at me. He slows, but doesn’t make space. There is a wailing and amber light engulfs us.
Stay back! he hisses.
Of course I have no choice but to stay back. As usual. He won’t let me pass. I try again to move to one side.
Now he’s slowing down, but he’s holding out his arm. The noise is deafening. Whining. Screaming.
He’s looking back at me.
It’s not safe!
Within the amber lighting I can see a blur of blue and yellow. My train! It’s hurtling past me, a massive tonnage of metal relentlessly responding to electrical charges initiated on an atomic level and upwardly scaled to the real and tangible motion of matter of the train.
I squeeze hard on my brakes; friction from the rubber on the front wheel losing its purchase on the ground which slides out from underneath me. When I roll over and get on all fours I see my bike in pieces near the rail track.
No. My bike is still in one piece. That’s his bike; a twisted frame with sheared rough edges of metal agape.
I stand and walk towards it. Blue light is flashing, but it’s hardly doppler. He’s nowhere to be seen.
He saved my life; my current existence is because of him. But I’ll never seen him again. It’s ironic that I never wanted to see him but now I want to, at least just to say thank you. But that can’t ever happen.
There’s his chair – empty, as if he never existed. Just a ghost through a train window.
Now that we’re in summer time I departed for work on a train which left – relatively speaking (and even though it turned up late) – an hour earlier than the same time last week.
I found myself sitting on a journey which previously, morning by morning, had got steadily brighter. Now, like a temporally backward hiatus, I was thrust back into darkness, at least for the first leg.
It’s fairly dark in the mornings at 7 am (summer time) at this time of the year in Holland, but as the vagaries of light reflecting upon the outside world and hitting my dreary retinas became clearer, I was shocked to see the ground covered in a frost of icy but magical fairy tales, and trees draped in ice like spectres of the night.
What had happened to the daffodils and tulips and other spring-ey kind of things I had glimpsed only days before? Had I finally traversed through time on a train, upon which I have had seemingly endless musings about time travel?
It wasn’t too long of a wait until I realised what I was looking at: white blossom and the usual dreary white concreted grounds of Holland. So no time travel (which regrettably in this world of predictability, comes as no surprise).
A couple of stations further on a gentleman seated himself opposite me with the assistance of a white cane. His gaze was distant, though I’m sure that his sight was indeed incredibly – if not infinitely – short-sighted.
Most other passengers (and despite my third person observation of them I include myself here as one of them) were using vision to gauge our traversal across space all the while passing the time. Our visually impaired travelling companion was not optically equipped to keep himself so-occupied in this way.
What was going through his mind I had no clue, but surely his mind was not as cloudy as his vision; he had navigated the platform, the train doors and the passage way to find his seat by the glass door separating the populated carriage with the entrance hall of the train all without the assistance of onlookers and those with whom he was embarking the carriage.
How does a blind man see the world in his imagination? Against what observation or perception does he measure his journey, be it the distance towards his destination, or marking the passage of time, the punctuation of which is so necessary to alleviate the boredom of doing nothing?
A piercing whistle dragged me from my thoughts and from those of the blind man back to the train which lurched suddenly to a stop.
Shortly a lady sporting too much make-up and armed with five small paper bags hooped in the crook of her inner elbow burst through the door. She was evidently relieved to not have missed the train which, even as she was bustling down the aisle, was accelerating away from the station at a pace to make up for lost time.
The glass door flung to behind her, beginning to trace the path along its predestined and extravagant pendulumous swing, seeking its final resting point of closed equilibrium at the end of its trajectory. Without turning his head, the blind man reached out his arm and let the door fall back on his hand, fingers slightly splayed.
As he allowed the beveled edge of the door to gently caress his hand and come to a silent rest, I came to realise that perhaps this soul whose perception of the world was won through audio means, and maybe an as yet unknown further sense, was more aware of space and time than the rest of us are.
I continued reading my book, The Time Machine. It was a reread, and though the words on the pages were invariably the same as the first time I had read it, they had struck my consciousness and I found that they spoke to me now with a deeper clarity than before. I put my book away as the train neared my station. I glanced out of the window and caught sight of the rising sun which was still low, a perfect disk of orange through the mist.
Unlike the large dull red future sun of Wells’ Time Machine, my sun would live to see – or indeed create – another day. I rose from my seat, though not as majestically as either the sun of the future of the present. I followed my doppleganger and stepped off the train, ready to embrace what that day had in store for me.
So tonight’s the night. (Or is it tomorrow morning’s the morning). At 2 am we put our clocks forward to 3 am, and await the semi annual discussion of whether it’s a good idea or not, and whether we should just keep summer time in place in winter, and in summer put the clock forward an additional hour.
Actually there are two things to spot…firstly that it would be summer time in winter, and secondly, we “spring forward” an hour in spring…and call it “summer time”.
Ah well. Us humans can be a little bit crazy like that, but I suppose we have to live with it.
Anyway. I’ve got into the habit of changing the clocks in my house the evening before. I’m not at my best in the morning, and looking at the clock on the bedside cabinet and then trying to remember that I need to add an hour and then remember I should have woken up an hour earlier is just never going to happen. (Who is awake at 2 am to change clocks??)
So I started downstairs at 18:50, and moved the clocks to 19:50. At 19:00 (i.e. 20:00 according to the downstairs clocks) it’s time for my girls to hit the sack. Cue the tooth brushing, bed time stories etc. and 45 minute later they’re both down. But before I head back downstairs, it’s time to set the upstairs clocks.
From 19:50 to 20:50.
Now I know it’s an hour since I was downstairs doing the same thing, but there’s a certain part of me which thinks I’ve just put the clocks forward 2 hours.
We naturally tend to think ahead, so is our psychology mapped to the future? How would you respond to the following question:
When do you feel happier – 3 pm on a Friday, or 9 pm on a Sunday?
Many would say the former, as the weekend is approaching when we’re not shackled up with employment. The irony is that at 3 pm on a Friday afternoon we’re still at work when we’d rather be at home…like at 9 pm on a Sunday evening.
Some time ago I wrote about an infinitesimally small moment in time by using a thought experiment involving a fly and a train.
We know from harsh experience that trains don’t run on time. Like mine this morning, which was cancelled. Or perhaps occupying an infinitesimally small spaces. Whilst watching the wheels on the…train (on the opposite platform) go round and round, I got round to thinking about the point of contact between the wheel and the rail.
Let’s assume that the train wheel is perfectly circular and incompressible, and that the train line is perfectly straight and also incompressible. How much of the wheel touches the train line?
OK, I’m no graphic designer, but I’m trying to show that no matter how much you zoom in, the point of contact between a circle and a straight line remains just that – a point.
No. I can see no other way of seeing it – the wheel is lucky to be touching the track at all! Well maybe that explains the hovering time travel train in Back to the Future III ! 😉
On a more serious note…this linking between time and space. If I can just figure out the implications on time, then maybe I’ll know if my train will turn up on time tomorrow…
I recently started a new job; they pay me peanuts, but it’s worth it. Why? Because it’s research in a fascinating subject and not an unchallenging position where I’m reduced to clock watching. (Please note I’d like to think that I’m capable enough to perform this work with a greater statistical likelihood than an infinite number of monkeys producing the works of Shakespeare 😉
My previous job was a bore. I’d sit in the office staring at my watch just waiting for the tedious hours to pass. Waiting to spend my time in the way I want it, where I wanted it.
Was spending 8 hours a day like this worth the money?
At the time I thought it was, but from my new present position I must say that I have really learnt that time spent wisely is worth so much more then money. Money can be hard to come by, but it’s even harder (for now) to get more time.
For now, I love what I do…but I still wish someone would hurry up and invent that time machine!
When I picked up my daughter from school today, she was proudly carrying a ring binder full of drawings and things she’d done over the past week or so. She was very happy until we got home and started showing them off to me, and found that one sheet had not been hole punched.
“Daddy, can we go out and buy a hole punch now?”
“No Sweetie, the shops are closed. We can go tomorrow.”
“Can’t we go yesterday?”
I’d like to think that I’m doing a good job in raising my daughter to think outside the temporal box!
Place a thermometer into boiling water, and it will read 100 degrees centigrade. Now plunge the same thermometer into a bucket of ice. The difference in temperature is (at least) 100 degrees, but there is a lag with the thermometer reading. It won’t immediately read 0 degrees, but it will go through the intermediate temperatures (albeit quickly) from 100 degrees, down to 0.
It can easily be argued that the thermometer is in part reading the temperature of itself – it’s own internal temperature, rather than the true ambient temperature.
Keep this in mind as we take an instantaneous journey through time in a time machine…
In an earlier post I demonstrated how the progression of time through space is instantaneous. But how does time progress in a time emachine?
Consider this. A person goes in a time machine and is instantly placed from the present to say 100 years into the future (as far as “instant” is possible…let’s call it experienced time).
Will the watch he’s wearing read t = 0 and instantly transform to t = 100 years? Or like the thermometer, will it pass through all the intermediate times like the thermometer read intermediate temperatures? Will he?
It might seem that a watch, by changing from one state of time to another, intrinsically needs to go through the intermediate times. But this implies a non instant travel. It sounds a little paradoxical that instant time travel means travelling [instantly] through all times in between!
Alternatively, does the watch measure the moment of ambient time, such as a GPS receiver ‘checking in’ to a satellite clock signal? Or does it measure the progression of experienced time?
I mentioned that this particular time machine operates instantaneously. That is to say that the “experienced time” is zero. Ambient time, therefore undergoes an instant change. This raises the question of how is an instant change in time possible?
Let’s pause for a moment on a slight detour and consider a well known thought experiment. On a train.
A train is traveling at a constant speed of 125 mph towards the west. A fly is buzzing in exactly the opposite direction, on a collision path with the train.
The collision inevitably takes place, and I think it’s fair to say that neither the train or the fly are aware of the event.
Now let’s consider the movement of the train and the fly.
The train is moving to the west at constant speed, collides with the fly, and continues its movement to the west (with a very slightly reduced velocity owing to increased combined mass with the fly).
The fly was flying towards the east. It collides with the train, then moves with the train towards the west. This means that the fly’s velocity changes sign, i.e. it goes from an arbitrary positive, through zero, to negative.
At the moment that the fly had zero velocity, it was in contact with the train. It might seem logical to assume that the train must therefore also have a zero velocity…but we know from experience that this is not the case.
We have therefore defined an infinitesimally small moment in time, but how to explain it? (Aside – this is the great thing about time travel – one question leads to another! 🙂 )
I was spinning on a roundabout with my daughters last week trying not to retch. They were fine; they were sitting near the middle, whereas I was on the outer rim. How was it possible that I had a greater linear velocity than they, and yet we were all in contact, much like the fly and the train?
The clue is that we were sitting on the same roundabout, undergoing the same angular velocity. Even the infinitesimally small point in space in the dead centre…was still rotating at the same rate as the rest of us.
And there it is. Angular velocity. I suppose that it’s not for nothing that people talk about the wheel of time! 😉
So back to our question of how is local ambient time experienced in an instantaneous time machine. Could it be that the local time is compressed or contracted to a point of ‘zero time’, (not to be confused with t = 0, an arbitrary reference time point) and regrows back to a new time? This zero time point would be analagous to the ‘fly point’ of zero velocity, or the zero space point on the roundabout.
Progression along the radius of the roundabout maintaining constant angular velocity showed that these zero points are possible. How that can be translated to time, or get it to regrow again…well there lies the magic of a time machine!
Consider the chart below. The curves are two simple sinusoids, and represent, say, the variance of the height of two swings above the ground as they swing in a simple harmonic motion.
Which of the swings, blue or red, would you say is in the lead?
For most, the instinct is to believe that the blue swing is in front.
But this would be wrong! The blue swing in fact lagging behind the red swing!
Even with the x axis labelled as “Time”, we are predisposed to visualise the sine curves in space and not in time.
When we read off the sine wave maxima on the x-axis we can see that the blue swing reaches it’s maximum height at t = 1.5 seconds, whereas the red swing already reached it’s maximum height half a second earlier at t = 1 second.
So the red swing is in the lead.
Somehow it seems counter intuitive, that the red swing got there first. It made its history first. It’s sitting there in the past, yet it’s in the lead.
I suppose it depends on how you look at it. Maybe it’s just swings and roundabouts!
In the latter article I gave the example of the Earth rotating around a non existent sun after for some reason the sun ceased to be; the transmission of information that the sun ceased to be (one parameter being the existence of gravity) would take some 8 minutes to reach the Earth. The Earth would therefore remain in orbit around a non existent sun for those transitional 8 minutes.
Archimedes had his brainwave whilst he was taking a bath. I had mine during a shower, watching the waste water spiral down through the plug hole. In true Archimedian style I thought to myself “Screw it.”
Why? Surely there must be something out there that can exceed the speed of light.
And I might have found it.
Let’s return to our orbiting Earth (or at least, remain firmly affixed to it’s surface, thanks to our gravitational friend).
As far as we are concerned, sitting (or showering) on the Earth, everything is hunky dory until the Sun disappears, the light goes out and we are flung into space obeying Newton’s second law of motion (i.e. that we travel in a straight line at constant speed unless an external force [in this case, the Sun’s gravity] is applied.
We know that the sun must have vanished 8 minutes ago, so let’s call that moment t = 0 and the present t = 8.
So from the perspective of the Earth at t = 8 we know that the sun vanished at t = 0.
And on the sun, the sun vanished at t = 0. At the same time, i.e. at t = 0. The event of our hindsight knowledge and the event itself was simultaneous.
Is hindsight instantaneous?
I think the example shows that the progression of time across space is instantaneous, although I do concede that it’s a bit strange to give time a speed when it is itself a term in the equation! (speed = distance divided by time!
â€œWhen we see the shadow on our images, are we seeing the time 11 minutes ago on Mars? Or are we seeing the time on Mars as observed from Earth now? Itâ€™s like time travel problems in science fiction. When is now; when was then?â€ â€“ Bill Nye.
Yesterday (or was it last week? 😉 ) I posted a timely thought which explained why history is important. I used an example of flipping an unbiased coin which repeatedly turned up tails, and stated that even though historical performance would suggest another tails on the next flip, the chances of heads showing on the next flip was still 50%.
I think a 50% chance of a heads showing is incorrect. It should be higher!
This is because that there are 2 possible outcomes of a flipped coin, so 50% chance of getting either one of them. The implication then is that with 2 coin flips, we’d expect 1 head and 1 tail. With 4 flips we’d expect 2 heads and 2 tails.
With 100 flips, we’d expect 50 heads and 50 tails.
But who’s to decide the order in which those heads and tails come? Alternate? Or all one and then the other?
So take the example in my original post where 50 flips had given tails. I’d stated a 50% probability of the next flip being heads. But if the probability is 50% for 100 flips, then the probability of the 51st flip being heads is now…100% !!!
So it seems that history is even more important than I had previously thought…although I wonder whether this is because we know something about the future i.e. there will be 100 coin flips and then no more.
But let’s add in a parallel consideration…we’ve considered this particular coin, but shouldn’t we be taking in all coins, and all of their flips, ad infinitum? That would mean we’re back at a 50% chance of a head.
So boundary limits impact the probability; events at all places at all times impact the importance of history and what that history means for the future.
Interesting that although I’m now a little wiser in the future…a little hindsight about foresight would have helped when I first wrote!
I’m not one for history. It relates to things in the past. Not necessarily forgotten about, but it’s been, it’s gone, and it’s over. Done and dusted.
But however dusty those history books might be, I do concede that history is important. I hold no sympathy for the “You don’t know where you’re going if you don’t know where you’ve been” line, but history can effect the present and the future.
Here’s an example.
An unbiased coin is flipped, and tails comes up.
It’s flipped again, and again it’s tails.
And it’s tails again and again and again, and so on…at 50 flips the coin is still coming up tails.
The probability of heads coming up for the 51st flip, mathematically speaking, is still 50% i.e. there is an equal chance of getting either heads or getting tails.
But given the history, what would you bet on…heads or tails?
The clocks go back an hour tonight. The addition or subtraction of an hour twice a year in an effort to optimise daylight hours has been going on for years, and yet still causes countless people to get confused, turning up too late or too early to various appointments.
It might seem like some sort of pseudo time travel when people turn up at different places at times they thought were different, but it’s just time (or it’s representation) moving onwards (or backwards as is the case now) and not taking us along with it on it’s hourly journey.
Spring forward, fall back.
Now it’s Autumn. We ‘gain’ an hour, but lose the sunlight. I for one am happy as I can stay in bed longer tomorrow morning. In theory anyway – I have two young children that haven’t mastered the concept and will still wake 3 hours before I’m ready to get up.
For the rest of you…enjoy the pseudo time travel! Your time is precious – use your hour wisely! 🙂
Recently, the following question was posed in the Goodreads.com Time Travel group:
“If you discovered a way to travel through time by using a photograph, which photo (personal or historical) would you use? Feel free to include…an explanation of why you chose it.”
I wanted to repost my response to that question here as my answer will serve as an introduction to a forthcoming post.
Here it is…
I’d use a picture that my 3 and a half year old daughter made with my wife a few months ago. It shows a picture of a watch and a clock, and shows the abstractness you could imagine from a young child.
Or is it abstract? Perhaps it’s an accurate statement of the real workings of time!
Why do I choose this picture? I think my daughter’s understanding of time and the possible ramifications for time travel is excellent given the conversations I’ve had with her about time. I’ll quote from a post in my Daddy blog about children’s understanding of time.
Me: (showing her a clock) “That fast hand goes all the way around, and thatâ€™s one minute, and then that long hand moves forwards a little bit. And when it goes all the way around, then thatâ€™s one hour and the short hand moves from number 1 to number 2.”
Daughter: “But Daddy the hands are moving all at the same time!”
If the second, minute and hour hands all move together, does this mean that seconds, minutes and hours all pass at the same time? Are seconds, minutes and hours pretty much all one and the same? Maybe they are for a three (and a half) year old. Everything happens at once, NOW…
Daughter: Can I have this now, Daddy?
Me: No, You can have it later, Sweetie.
Daughter: Is it later now, Daddy?
I’m also sure that on the day she gets married and I walk her down the aisle, I’ll be taken back in time to these childhood moments…but I don’t think I’ll need the picture then!
As for when the picture would take me…I don’t really care, as long as it would take me back again to my family. These moments in time are far too precious to lose!
This post won me a copy of “The Photo Traveler” by Arthur J. Gonzalez. I’m currently reading it, and I’ve been asked to provide a review.
So stand by!
PS: I’ve only ever won 2 things. This was one. The other was a rag doll at a tombola when I was 8. Although my daughter might disagree, the time travel novel comes out tops!